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Submerged macrophytes are crucial for the restoration of shallow eutrophic lake but they are diminished in coverage or lost with eutrophication. Their recovery after nutrient loading reduction depends on water and sediment nutrient levels. We studied the combined impacts of sediment fertility (low/high nitrogen and phosphorus content) and water nutrient concentrations (low/high nitrogen and phosphorus addition) on Vallisneria denseserrulata in a mesocosm experiment. We hypothesized that both the elevated external nutrient addition and high sediment nutrient contents would inhibit plant growth. We found that an increase in nutrient concentrations resulted in a significant increase in algal biomass. Furthermore, high external nutrient addition significantly reduced both the relative growth rate (RGR) and the density of V. denseserrulata growing in the nutrient-rich sediment, while in the nutrient-poor sediment treatment, RGR was not affected but the plant density decreased. Interestingly, low nutrient addition appeared to be more conducive to growth and reproduction of V. denseserrulata in the nutrient-rich sediment than in the nutrient-poor sediment. Our findings emphasize the importance of reducing external nutrient inputs is of key higher importance when restoring shallow eutrophic lakes, while the plants may benefit of the nutrient-rich sediment occurring in such lakes after eutrophication. [ABSTRACT FROM AUTHOR]

Peanut optimal planting density is necessary to obtain the maximum yield. Also, peanut as heavy feeder of nutrients needs to be supplemented through foliar application and bio-fertilizer (BF) plays an important role in food safety and sustainable production. This experiment was done in Rasht, Iran, during the 2017–2018 and 2018–2019 cropping seasons and carried out as split-factorial based on randomized complete blocks design with three replications. Three planting densities including 83,333 (PD1), 100000 (PD2) and 125,000 (PD3) plants ha−1 in main plot, four levels of BF including no application of BF as control (Z0) as check, Rhizobium spp. (RB), Arbuscular mycorrhizal fungi (AMF) and the combined application of RB + AMF and three treatments of magnesium (Mg), molybdenum (Mo) and Mg + Mo as factorial 4 × 3 in sub plot, comprised experimental treatments. The tripartite interaction of PD2 × (RB+AMF) × (Mg+ Mo) produced the greatest seed yield (3515 kg ha−1), pod yield (4472 kg ha−1), biological yield (9380 kg ha−1), oil yield (1515 kg ha−1) and protein yield (793 kg ha−1). Also, the application of AMF along with Mo fertilizer increased the content of OA (58.51%) and SA (4.43%) in PD1 treatment. According to the results of this experiment, the inoculation of RB + AMF along with foliar application of Mg + Mo in PD2 treatment enhanced the SY of peanut and combined application of AMF and Mo improved oil quality in PD1 treatment and be recommended to enhance quantitative and qualitative yield of peanut under similar climatic conditions. [ABSTRACT FROM AUTHOR]

Peanuts play a crucial role as an oil crop, serving not only as a primary source of edible oil but also offering ample protein and vitamins for human consumption. The lateral branch angle of peanuts is the angle between the main stem and the first pair of lateral branches, which is an important agronomic trait of peanuts, significantly impacts the peg penetration into the soil, plant growth, and pod yield. It is closely intertwined with planting density, cultivation techniques, and mechanized harvesting methods. Therefore, the lateral branch angle holds substantial importance in enhancing peanut yield and facilitating mechanization. In order to conduct in-depth research on the lateral branch angle of peanuts, this research is grounded in the QTL mapping findings, specifically focusing on the QTL qGH associated with the lateral branch angle of peanuts located on chromosome B05 (142610834-146688220). By using Jihua 5 and PZ42 for backcrossing, a BC1F2 population comprising 8000 individual plants was established. Molecular markers were then developed to screen the offspring plants, recombine individual plants, conduct fine mapping. he results showed that using the phenotype and genotype of 464 recombinant individual plants selected from 8000 offspring, narrow down the localization interval to 48kb, and designate it as qLBA. The gene Arahy.C4FM6Y , responsible for the F-Box protein, was identified within qLBA through screening. Real-time quantitative detection of Arahy.C4FM6Y was carried out using M130 and Jihua 5, revealing that the expression level of Arahy.C4FM6Y at the junction of the main stem and the first lateral branch of peanuts was lower in M130 compared to Jihua 5 during the growth period of the first lateral branch from 1 to 10 centimeters. Consequently, Arahy.C4FM6Y emerges as a gene that restrains the increase in the angle of the first lateral branch in peanuts. This investigation offers novel genetic reservoirs for peanut plant type breeding and furnishes a theoretical foundation for molecular marker-assisted peanut breeding. [ABSTRACT FROM AUTHOR]

This study focuses on Daphne rodriguezii, a threatened plant species that is endemic to Menorca in the Balearic Islands of the Western Mediterranean. The main objective was to investigate the volatile organic compounds (VOCs) in the floral aroma, as well as the timing and chemical variations in scent production. The primary pollinators were identified, and the relationship between their behavior and the chemical profile of the floral scent was investigated. Furthermore, the impact of plant density on fruit set rates was evaluated to obtain valuable insights for conservation and habitat‐management initiatives. The findings reveal that D. rodriguezii emits a distinct sweet floral aroma that primarily consists of benzenoids and linalool derivatives. Scent emission occurs during the evening and night, coinciding with the activity period of moths (Autographa gamma), which were identified as the primary pollen vectors for this self‐incompatible species. The fruit set values exhibit a positive correlation with the proximity between plants. These results emphasize the importance of moths and plant proximity as crucial factors to consider in the conservation management of this species. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) has been shown to be sensitive to temperature deviations, influencing its yield potential. The development of new maize hybrids resilient to unfavourable weather is a desirable aim for crop breeders. In this paper, we showcase the development of a multimodal deep learning model using RGB images, phenotypic, and weather data under temporal effects to predict the yield potential of maize before or during anthesis and silking stages. The main objective of this study was to assess if the inclusion of historical weather data, maize growth captured through imagery, and important phenotypic traits would improve the predictive power of an established multimodal deep learning model. Evaluation of the model performance when training from scratch showed its ability to accurately predict ~89% of hybrids with high-yield potential and demonstrated enhanced explanatory power compared with previously published models. Shapley Additive explanations (SHAP) analysis indicated the top influential features include plant density, hybrid placement in the field, date to anthesis, parental line, temperature, humidity, and solar radiation. Including weather historical data was important for model performance, significantly enhancing the predictive and explanatory power of the model. For future research, the use of the model can move beyond maize yield prediction by fine-tuning the model on other crop data, serving as a potential decision-making tool for crop breeders to determine high-performing individuals from diverse crop types. [ABSTRACT FROM AUTHOR]

Mississippi soybean [Glycine max (L.) Mer.] producers are under pressure to plant as much land as possible within narrow planting windows. The 5‐year average planting progress is 45% of the total at the end of the optimal soybean planting window. New metering and seed delivery technology claims faster planting without sacrificing singulation, stand, or yield, but these tools need to be validated before recommendation. This study aimed to quantify soybean response to planting speeds using a precision planter (John Deere MaxEmerge 2 row units retrofitted with Ag Leader SureSpeed and SureForce) and a mechanical planter (John Deere 1700 ground‐driven mechanical planter equipped with eSet meters) for a total of 7 site‐years across Mississippi. In 2022, both planters were evaluated at four actual ground speeds of 7.9, 10.8, 13.5, and 16.4 km h−1 in a 2 × 4 factorial design. The experimental design was modified in 2023, where the mechanical planter served as the current farmer practice check at 9.7 km h−1and the precision planter speeds were 9.7, 14.5, and 17.7 km h−1 at research station sites and 9.7 and 14.5 km h−1 at an on‐farm site. Across sites, increased planting speed generally increased plant spacing, in‐row spacing variability, and decreased plant population. However, increased speed did not affect soybean yield. The precision planter at 17.7 km h−1 was no different from the mechanical planter in terms of soybean plant population, spacing, and yield in 2023. Results suggest soybean producers can plant soybean at 17.7 km h−1 without compromising yield. Core Ideas: Planting within optimal planting dates maximizes soybean yield.Planting faster results in more area planted during ideal planting dates.No yield difference was observed when planting up to 17.7 km h−1 during 7 site‐years.Reduction in stand occurred with faster planting speed but was never yield‐limiting. [ABSTRACT FROM AUTHOR]

Mali is among Africa's three biggest cotton (Gossypium hirsutum L.)‐producing countries, and cotton growing is the principal driving force behind Mali's agricultural sector. Cotton production is rainfed on small‐scale family farms as a commercial crop alongside staple crops grown for subsistence. Cultivar choice, planting date, and planting density are critical elements for seed cotton yield that should be optimized. This study aimed to understand the interactions between planting dates and planting densities for the optimal production of four cotton cultivars in Mali. Two trials were set up in two seasons at the Finkolo and N'Tarla research stations. A split‐plot design with four replications was used, with planting dates (early and delayed by 3 weeks) as the main plots and planting density (41,666; 83,333; and 166,666 plants/ha) and cultivar (Malian NTA MS334, Togolese STAM 129A, Australian SIOKRA L23, and Brazilian BRS 293) as the subplots. In 2021, seed cotton yield was 1263 kg/ha for early planting versus 361 kg/ha for late planting. Medium and high planting densities produced the same yield level, higher than the low planting density. Regardless of the planting density, early plantings' average capsular weight and seed index were higher than those of late plantings. The African cultivars (STAM 129A and Malian cultivar NTA MS334) were the most productive. Due to significant interactions on fiber percentage and to optimize cotton yields in Mali, planting should be early, with planting densities higher than 41,666 plants/ha, and either of the African cultivars tested should be used. Core Ideas: Cotton cultivars from three continents were compared in 24 cropping situations in two sites and 2 years.There was no interaction between cultivar, planting date, and planting density on seed cotton yield.There was an interaction between planting date and cultivar on fiber content (percentage of fiber in seed cotton [%F]).The %F of African cultivars was high and was not affected by late planting dates.African cultivars performed better than others under early and late planting conditions. [ABSTRACT FROM AUTHOR]

We had assembled a synthetic bacterial community (SynComH) from the rhizosphere microbiota of Haloxylon ammodendron, which enhance drought tolerance in Arabidopsis thaliana under laboratory conditions. Here we assessed the efficacy of SynComH, alone or in combination with SynComS, a consortium of previously identified growth-promoting bacteria from Crocus sativus, in increasing maize plants' fitness under optimal and water-deficit conditions. We were also interested in unveiling the mechanisms by which the bacteria confer drought tolerance. We first performed detailed greenhouse experiments on maize plants that were artificially inoculated with SynComS, SynComH, and SynComH+S, and measured 22 different plant morphological, physiological, biochemical, and histological traits under optimal and water-deficit conditions. Data were analyzed by different univariate and multivariate statistical methods. Lastly, we tested the effects of the SynComs on maize in field in a split-plot experiment with two irrigation regimes as main plots and SynComs as subplots. Results from both greenhouse and field experiments showed that all three SynComs had growth-promoting properties and improved growth-related traits, but only SynComH and SynComH+S were effective in ameliorating the drought stress. SynComH substantially enhanced drought tolerance by increasing stomatal conductance, photosynthesis rate, and proline content, while decreasing transpiration rate, leading to up to 700% increase of water use efficiency. Morphological and histological investigations suggested that these positive effects are probably attributed to modulation of plant stomatal density and xylem structure by SynComH. Besides the significance for practical agronomic use, our results suggest unprecedented capabilities of non-pathogenic bacteria in modulation of plant stomatal density. [ABSTRACT FROM AUTHOR]

Forest assisted migration (FAM) is the movement of tree species or genotypes to locations that are projected to be climatically suitable for future growth and survival. FAM can be an integral component of climate adaptation projects. An example of such a project is the Red Pine Adaptive Silviculture for Climate Change (Red Pine ASCC) experiment in northern Minesota, USA. The experiment includes planting seedlings of northern red oak and bur oak from two different seed sources south of the study area. The primary source for both species was central Minnesota, one seed zone south of the local zone. However, due to the number of seedlings needed, a secondary source was also used that included red oak from southwest Michigan and bur oak from eastern Iowa. Known planting locations and densities of the seed sources allowed comparison of survival and growth to assess if the primary seed sources out-performed the secondary sources. For both species, densities after five growing seasons were not significantly different between seed sources, suggesting similar survival. Heights and diameters of bur oak were nearly identical for the two seed sources, suggesting similar growth rates. For northern red oak, seedlings of the Minnesota seed source were taller and larger in diameter than the Michigan seed source, but differences were small. Our results suggest managers can be opportunistic when acquiring seedlings of these species for similar FAM projects. [ABSTRACT FROM AUTHOR]

Introduction: Due to limited arable land resources, intercropping has emerged as an efficient and sustainable production method for increasing total grain yield per unit land area. Maize-soybean strip intercropping (MSSI) technology is being widely promoted and applied across China. However, the combination of optimal density for achieving higher production efficiency of both soybean and maize remains unclear. The objective of this study was to evaluate the differences in yield, economic benefits, land, and nitrogen (N) efficiency in MSSI systems under different densities. Methods: Five maize/soybean density combinations (67,500/97,500 plants ha-1, D1; 67,500/120,000 plants ha-1, D2; 67,500/142,500 plants ha-1, D3; 60,000/142,500 plants ha-1, D4; 52,500/142,500 plants ha-1, D5) were set under the same N input in the field experiment. Results and discussion: The results demonstrated that optimizing the density in the intercropping system could enhance production efficiency. Increasing the density of soybean and maize significantly increased the total grain yield (D3 > D2 > D1 > D4 > D5). The D3 treatment, exhibiting the best comprehensive performance, also promoted increases in leaf area index, dry matter accumulation, and N absorption and utilization. Path analysis indicated that density had the most substantial impact on maize yield, while grain number had the greatest influence on soybean yield, with contribution rates of 49.7% and 61.0%, respectively. These results provide valuable insights into optimal field density for summer planting in MSSI, facilitating its wider adoption. [ABSTRACT FROM AUTHOR]

Bioregenerative food systems that routinely produce fresh, safe-to-eat crops onboard spacecraft can supplement the nutrition and variety of shelf-stable spaceflight food systems for use during future exploration missions (i.e., low earth orbit, Mars transit, lunar, and Martian habitats). However, current space crop production systems are not yet sustainable because they primarily utilize consumable granular media and, to date, operate like single crop cycle, space biology experiments where root modules are sanitized prior to launch and discarded after each grow-out. Moreover, real-time detection of the cleanliness of crops produced in spacecraft is not possible. A significant paradigm shift is needed in the design of future space crop production systems, as they transition from operating as single grow-out space biology experiments to becoming sustainable over multiple cropping cycles. Soilless nutrient delivery systems have been used to demonstrate post-harvest sanitization and inflight microbial monitoring technologies to enable sequential cropping cycles in spacecraft. Post-harvest cleaning and sanitization prevent the buildup of biofilms and ensure a favorable environment for seedling establishment of the next crop. Inflight microbial monitoring of food and watering systems ensures food safety in spaceflight food systems. A sanitization protocol, heat sterilization at 60°C for 1 h, and soaking for 12 h in 1% hydrogen peroxide, developed in this study, was compared against a standard hydroponic sanitization protocol during five consecutive crop cycles. Each cropping cycle included protocols for the cultivation of a crop to maturity, followed by post-harvest cleaning and inflight microbial monitoring. Microbial sampling of nutrient solution reservoirs, root modules, and plants demonstrated that the sanitization protocol could be used to grow safe-to-eat produce during multiple crop cycles. The cleanliness of the reservoir and root module surfaces measured with aerobic plate counts was verified in near real time using a qPCR-based inflight microbial monitoring protocol. Post-harvest sanitization and inflight microbial monitoring are expected to significantly transform the design of sustainable bioregenerative food and life support systems for future exploration missions beyond low earth orbit (LEO). [ABSTRACT FROM AUTHOR]

Translation abstract Cable support structure of the façade greening of the central warehouse of the Zurich Municipal Electric UnityThe façade greening of the new central warehouse of the Zurich Municipal Electric Unity (ewz) is an external structure made of supporting cables and hollow profiles that provides a total of 300 m2 of growing space for climbing plants. The supporting structure received a recognition at the award ceremony of the Prix Acier 2023 by the Swiss Center of Steel Construction (SZS). This article, which was presented in a similar form at the constructional steel day of the School of Engineering and Architecture of Fribourg in April 2024, documents the design process, the materialisation and structural design as well as selected aspects from the analysis and design of the supporting structure. [ABSTRACT FROM AUTHOR]

Out‐planting corals onto coral reefs as a mechanism to increase coral cover on degraded reef systems is an increasing global activity. Current practices typically focus on asexual out‐planting of coral fragments (coral gardening). Newer sexual reproductive approaches are being developed to out‐plant younger corals produced in aquaculture facilities or sea‐based rearing pools to enable assisted evolution or assisted gene flow conservation genetics approaches. Designing out‐planting deployment operations requires decisions to be made on planting density and location in order to maximize future recruitment on both the out‐planted reefs, and on nearby reefs that are connected through oceanographic transport processes. The thinking presented here seeks to unpack how out‐planting density may be influenced, especially by local oceanographic conditions, in order to guide practitioners undertaking restoration projects. [ABSTRACT FROM AUTHOR]

Ecological floating bed (EFB) has been widely used to remove nitrogen and phosphorus from eutrophic water. However, its effects on nitrogen and phosphorus removal are different in various studies. Presently it has not been systematically clear what factors produce effects on EFB removing nitrogen and phosphorus from eutrophic water. In this study, we performed a meta-analysis of 169 articles to discuss the effects of EFB characteristics and experimental conditions on EFB removing nitrogen and phosphorus. Results showed that EFB generally decreased nitrogen and phosphorus concentrations in eutrophic water regardless of EFB characteristics and experimental conditions. EFB showed better effects on simultaneously removing TN, NH4+-N, and TP when it had one of the characteristics: constructed by monocots, 2–3 plant species, an area of 1.1–3.0 m2, and the coverage of 21%-40%. However, NO3−-N removal by EFB was complicated due to the effects of nitrification and denitrification. Moreover, EFB plant density also showed different effects on nitrogen and phosphorus removal. Experimental conditions produced evident effects on EFB removing nitrogen and phosphorus, and it showed better effects under one of the conditions: water temperature of 16–25℃, experimental duration of 31–60 days, long hydraulic retention time, and aeration. This study indicates that EFB can significantly remove nitrogen and phosphorus from eutrophic water, and it is an effective technology to control water eutrophication, but the effects of EFB characteristics and environmental conditions on EFB function should be considered in application. [ABSTRACT FROM AUTHOR]

Eutrophication has been observed to decrease the ecological resilience of macrophyte‐dominated freshwater ecosystems, thereby resulting in more vulnerability to external perturbations and easily tipping into an algae‐dominated state. The stress‐gradient hypothesis (SGH) posits that plants exhibit positive plant–plant interaction (facilitation) in response to stress, potentially buffering the detrimental impacts of eutrophication. However, few studies attempted to link plant density with species‐species interactions and ecological resilience in the context of eutrophic stress. Here, we investigated how the density of neighbour plant species (Potamogeton lucens) affects the change rate of nutrients or Chl a (chlorophyll‐a) and target plant species (Potamogeton maackianus) along a gradient of nutrient levels (oligotrophic, mesotrophic, eutrophic) via a 42 days mesocosm experiment. Our objective was to corroborate: (1) species interactions may shift from competition to facilitation with the increased eutrophic stress. (2) High plant density is indispensable to generate facilitation and thereby augment ecological resilience under high eutrophic stress. Results showed that eutrophic scenarios significantly augmented chlorophyll‐a concentration and inhibited plant height, number of branches and leaves, showing that submerged macrophytes in eutrophic states are exposed to stressful conditions. However, the increasing density of neighbouring vegetation reduced nutrient and Chl a concentrations and enhanced the performance of Potamogeton maackianus in eutrophic conditions, but not in mesotrophic and oligotrophic conditions. Our results indicated that density‐dependent facilitation is more prevalent in eutrophic circumstances, and species interactions are likely transformed from competition to facilitation with increasing nutrient concentrations. Our research demonstrated that plant density could alter the relationship between facilitation and competition; high plant density is indispensable for the operation of the stress‐gradient hypothesis. Density‐dependent facilitation under severe conditions could mitigate the adverse influence of eutrophication. With freshwater ecosystems progressively subjected to eutrophication, harnessing the density‐dependent facilitation of submerged macrophytes in resilience‐driven management is crucial to inhibiting the transition to an algae‐dominated turbid state, which further broadens our understanding of the theory of alternative stable states in shallow lakes. [ABSTRACT FROM AUTHOR]

Peanuts play a crucial role as an oil crop, serving not only as a primary source of edible oil but also offering ample protein and vitamins for human consumption. The lateral branch angle of peanuts is the angle between the main stem and the first pair of lateral branches, which is an important agronomic trait of peanuts, significantly impacts the peg penetration into the soil, plant growth, and pod yield. It is closely intertwined with planting density, cultivation techniques, andmechanized harvesting methods. Therefore, the lateral branch angle holds substantial importance in enhancing peanut yield and facilitating mechanization. In order to conduct indepth research on the lateral branch angle of peanuts, this research is grounded in the QTL mapping findings, specifically focusing on the QTL qGH associated with the lateral branch angle of peanuts located on chromosome B05 (142610834-146688220). By using Jihua 5 and PZ42 for backcrossing, a BC1F2 population comprising 8000 individual plants was established. Molecular markers were then developed to screen the offspring plants, recombine individual plants, conduct fine mapping. he results showed that using the phenotype and genotype of 464 recombinant individual plants selected from 8000 offspring, narrow down the localization interval to 48kb, and designate it as qLBA. The gene Arahy.C4FM6Y, responsible for the F-Box protein, was identified within qLBA through screening. Real-time quantitative detection of Arahy.C4FM6Y was carried out using M130 and Jihua 5, revealing that the expression level of Arahy.C4FM6Y at the junction of the main stem and the first lateral branch of peanuts was lower in M130 compared to Jihua 5 during the growth period of the first lateral branch from 1 to 10 centimeters. Consequently, Arahy.C4FM6Y emerges as a gene that restrains the increase in the angle of the first lateral branch in peanuts. This investigation offers novel genetic reservoirs for peanut plant type breeding and furnishes a theoretical foundation for molecular marker-assisted peanut breeding. [ABSTRACT FROM AUTHOR]

Introduction: Optimizing the dynamics of daylily (Hemerocallis citrina Baroni) growth under various planting patterns is critical for enhancing production efficiency. This study presents a comprehensive model to simulate daylily growth and optimize planting patterns to maximize bud yield while minimizing land resource utilization. Methods: The model incorporates source-sink relationship specific to daylilies into physiological process modeling, considering environmental factors such as micro-light and temperature climate, and CO2 concentration. Spatial factors, including planting pattern, row spacing, plant spacing, and plant density were examined for their impact on light interception, photosynthesis, and resource efficiency. Employing partial least square path modeling (PLS-PM), we analyzed the interrelations and causal relationships between planting configurations and physiological traits of daylily canopy leaves and buds. Through in situ simulations of 36 planting scenarios, we identified an optimal configuration (Scenario ID5) with a density of 83,000 plants·ha−1, row spacing of 0.8 m, and equidistant planting with a plant spacing of 0.15 m. Results and discussion: Our research findings indicate that increased Wide+Narrow row spacing can enhance yield to a certain extent. Although planting patterns influence daylily yield, their overall impact is relatively minor, and there is no clear pattern regarding the impact of plant spacing on individual plant yield. This modeling approach provides valuable insights into daylily plant growth dynamics and planting patterns optimization, offering practical guidance for both farmers and policymakers to enhance daylily productivity while minimizing land use. [ABSTRACT FROM AUTHOR]

Optimizing planting density is crucial for balancing resource competition, light penetration, and tree productivity in orchard systems. This study investigateed the impact of planting density on the yield and fruit quality of the hazelnut cultivar 'Tonda Francescana®' grafted onto Corylus colurna L. rootstocks. The research aimed to assess how different planting densities influenced light penetration, canopy volume, yield, and the nutritional profile of hazelnuts during their sixth growing season. Three planting densities were tested: 625, 1250, and 2500 trees per hectare (low, medium, and high density, respectively). The results show that medium-density planting provided the best balance between light availability, canopy development, and yield efficiency. The synthesis of monounsaturated fatty acids (MUFA) and α-tocopherol (vitamin E) was more prominent in the medium-density system (80.2% and 10.3%, respectively), suggesting a favorable metabolic response to moderate competition for resources. In contrast, high-density planting yielded the most per hectare (2898 kg/ha) but exhibited lower individual tree productivity (1.16 kg). Low-density planting had the highest light penetration (53%) but lower overall yield (822 kg/ha) and quality, with greater starch accumulation in the fruit. In general, medium-density planting optimized both yield and kernel quality, with potential implications for orchard management and breeding strategies to enhance hazelnut production and nutritional value. [ABSTRACT FROM AUTHOR]

Summary: Multiple distinct specialized regions shape the architecture of maize leaves. Among them, the fringe‐like and wedge‐shaped auricles alter the angle between the leaf and stalk, which is a key trait in crop plant architecture. As planting density increased, a small leaf angle (LA) was typically selected to promote crop light capture efficiency and yield. In the present study, we characterized two paralogous INDETERMINATE DOMAIN (IDD) genes, ZmIDD14 and ZmIDD15, which contain the Cys2‐His2 zinc finger domain and function redundantly to regulate auricle development and LA in maize. Loss‐of‐function mutants showed decreased LA by reducing adaxial sclerenchyma thickness and increasing the colourless cell layers. In addition, the idd14;idd15 double mutant exhibited asymmetrically smaller auricles, which might cause by a failed maintenance of symmetric expression of the key auricle size controlling gene, LIGULELESS(LG1). The transcripts of ZmIDD14 and ZmIDD15 enriched in the ligular region, where LG1 was highly expressed, and both proteins physically interacted with ZmILI1 to promote LG1 transcription. Notably, the idd14;idd15 enhanced the grain yield of hybrids under high planting densities by shaping the plant architecture with a smaller LA. These findings demonstrate the functions of ZmIDD14 and ZmIDD15 in controlling the abaxial/adaxial development of sclerenchyma in the midrib and polar development along the medial‐lateral axes of auricles and provide an available tool for high‐density and high‐yield breeding in maize. [ABSTRACT FROM AUTHOR]

Sowing density and row spacing of barley affect the crop efficiency, resource use and final yield, with different genotypes likely to respond differently to this agrotechnical factor. The effect of sowing density on the barley yield, as shaped by structural yield elements such as the number of ears, number of grains per ears and thousand grain weight, depends on the interaction of this factor with the genotype and the growing conditions. Two spring barley genotypes with a black grain color (H. vulgare L. var. nigricans and H. vulgare L. var. rimpaui), differing in ear structure and affiliation to the original wild forms, were studied. Two independent, two-year field experiments were conducted in 2019–2020 and 2021–2022 at two locations with contrasting soil conditions. The effects of genotype and sowing density interactions on the yield, harvest index and structural elements of the yield were assessed. The arley yield was dependent on the interaction of genotype and sowing density but also varied by location. H. v. var. nigricans yielded better at higher densities, while H. v. var. rimpaui showed greater tillering potential at low densities. Environmental factors such as rainfall, temperature and soil composition affected the number of fertile ears, number of grains per ear and thousand grain weight. [ABSTRACT FROM AUTHOR]

Field robots are an important tool when improving the efficiency and decreasing the climatic impact of food production. Although several commercial field robots are available, the advantages, limitations, and optimal utilization methods of this technology are still not well understood due to its novelty. This study aims to evaluate the performance of a commercial field robot for seeding and weeding tasks. The evaluation was carried out in a 2-hectare sugar beet field. The robot's performance was assessed by counting plants and weeds using image processing. The YOLOv8 model was trained to detect sugar beets and weeds. The plant and weed densities were compared on a robotically weeded area of the field, a chemically weeded control area, and an untreated control area. The average weed density on the robotically treated area was about two times lower than that on the untreated area and about three times higher than on the chemically treated area. The testing robot in the specific testing environment and mode showed intermediate results, weeding a majority of the weeds between the rows; however, it left the most harmful weeds close to the plants. Software for robot performance assessment can be used for monitoring robot performance and plant conditions several times during plant growth according to the weeding frequency. [ABSTRACT FROM AUTHOR]

A two-factor split-plot experiment was carried out in the greenhouse of Linyi agricultural meteorological experimental site using muskmelon 'Xizhoumi 25' as the experimental material. The main area was two planting patterns of single row on ridge (D1) and double row on ridge (D2), and the sub-area was three kinds of melon nodes of 11-12 nodes (R1), 13-14 nodes (R2) and 15-16 nodes (R3), a total of 6 treatments, The plant leaf area and photosynthetic parameters, yield components and fruit quality were measured to explore the effects of different planting patterns and melon retention nodes on photosynthetic characteristics, yield and quality of muskmelon in greenhouse. The results showed that the photosynthetic efficiency of single row planting mode was higher than that of double row planting mode. The fruit diameter, single fruit weight and soluble sugar content of single row planting mode were significantly increased by 2.4%, 11.1% and 9.5%, respectively, compared with double row planting mode (P<0.05). The effect of node location on vegetative growth and reproductive growth of the plant was obvious. The photosynthetic characteristics, fruit length, fruit diameter and single fruit weight of R2 treatment were the best, and the single fruit weight was 9.41% and 14.73% higher than that of R1 and R3, respectively (P<0.05). The effect on fruit quality was extremely significant (P<0.01). The R1 treatment had the highest soluble sugar content, the R2 treatment had the highest sugar-acid ratio, and the R3 treatment had the highest VC and titratable acid content. The interaction between planting pattern and node position had significant effects on leaf area, SPAD, Pn, Ci, Gs and Tr of muskmelon (P<0.05), and the SPAD, Pn, Gs and Tr values of D1R2 combination leaves were the largest before maturity. The interaction had a significant effect on fruit length (P<0.05), and had a very significant effect on fruit diameter, fruit shape index and single fruit weight (P<0.01). Among them, the fruit diameter value of D1R1 combination was the largest, and the fruit shape index of D1R3 was the highest. The fruit length and single fruit weight of the D1R2 combination were the largest, and the average single fruit weight was 28.7% higher than that of other combinations. The interaction had a significant effect on VC content (P<0.05), and had a very significant effect on titratable acid, soluble sugar content and sugar-acid ratio (P<0.01). Of these, the D2R3 combination had the highest VC content, D1R3 had the highest titratable acid content, D1R1 had the highest soluble sugar content and D1R2 had the highest sugar-acid ratio. Under the same planting density and number of functional leaves (22500 plants·ha-1, 25 nodes topping), the three evaluation indexes of yield flavor and taste and VC content of single row planting on ridge and 13-14 nodes interaction (D1R2) mode were the highest, and the comprehensive evaluation of its commodity value was the best. It is recommended that this mode of planting should be applied and generalized in the vertical cultivation of the early spring melons in greenhouses in the north of China. [ABSTRACT FROM AUTHOR]

Assessing the quality of maize seedlings is crucial for field management and germplasm evaluation. Traditional methods for evaluating seedling quality mainly rely on manual field surveys, which are not only inefficient but also highly subjective, while large-scale satellite detection often lacks sufficient accuracy. To address these issues, this study proposes an innovative approach that combines the YOLO v8 object detection algorithm with Voronoi spatial analysis to rapidly evaluate maize seedling quality based on high-resolution drone imagery. The YOLO v8 model provides the maize coordinates, which are then used for Voronoi segmentation of the field after applying the Convex Hull difference method. From the generated Voronoi diagram, three key indicators are extracted: Voronoi Polygon Uniformity Index (VPUI), missing seedling rate, and repeated seedling rate to comprehensively evaluate maize seedling quality. The results show that this method effectively extracts the VPUI, missing seedling rate, and repeated seedling rate of maize in the target area. Compared to the traditional plant spacing variation coefficient, VPUI performs better in representing seedling uniformity. Additionally, the R2 for the estimated missing seedling rate and replanting rate based on the Voronoi method were 0.773 and 0.940, respectively. Compared to using the plant spacing method, the R2 increased by 0.09 and 0.544, respectively. The maize seedling quality evaluation method proposed in this study provides technical support for precision maize planting management and is of great significance for improving agricultural production efficiency and reducing labor costs. [ABSTRACT FROM AUTHOR]

Summary Dwarf plant architecture facilitates dense planting, and increased planting densities boost the maize yield. However, breeding applications of dwarfing materials for maize are currently limited. There is an urgent need remove the obstacles to applying dwarf resources. Here, we innovated a new method to add a novel maize dwarf germplasm through the distant hybridization of Maize–Tripsacum–Teosinte allopolyploid (MTP) with maize. We identified ten independent dwarf families with unique characteristics. Five germplasms in our library were controlled by their respective dwarf genes. However, no allele was controlled by Br2. Subsequently, d024 in the library was successfully fine mapped, revealing its linkage to indel‐4 in ZmCYP90D1. The indel‐4 polymorphism regulates the expression of ZmCYP90D1 and is controlled by an upstream transcription factor (ZmBES1/BZR1‐5). The indel‐4 of ZmCYP90D1 allele, which reduces plant height, originated from Tripsacum, a wild variety of maize. However, d024 exhibits sensitivity to brassinosteroids (BRs), with lower castasterone levels in the internodes than that in the wild type. Furthermore, ZmCYP90D1 interacted with ZmFDXs and ZmNAD(P)H to positively regulate the downstream BR synthesis pathway. Additionally, we showed that introgressing the indel‐4 of the Tripsacum allele into modern hybrids ensures yield potential and improves the harvest index under high‐density conditions. Overall, as we begin to manufacture highly engineered dwarf materials using the MTP, this approach will solve the problems faced by corn dwarfs. [ABSTRACT FROM AUTHOR]

We conducted long-term monitoring of Hypogeococcus sp. (Pseudococcidae) as a biocontrol agent for queen of the night cactus (Cereus jamacaru De Candolle). The biocontrol agent was released at three sites representing the regions where the plant is problematic in South Africa, and both agent and plant populations were monitored over time. The proportion of plants producing fruits or flowers decreased by 36% each year, with all plants no longer flowering between two and seven years after release. Plant density reduced by 42% each year after release. Hypogeococcus sp. is an effective agent against C. jamacaru in South Africa. [ABSTRACT FROM AUTHOR]

A novel method for the mechanical detection of wheat biomass, based on the mechanical properties of wheat plants, is proposed to enable the quick assessment of wheat biomass. The mechanical model developed for the wheat plants, based on the variable cross-section beam elastic bending theory, can be used to analyse the interactive forces between the reel and wheat plants, and predict wheat biomass based on the magnitude of the force. The influence of wheat ears on deflection was incorporated into the model. The accuracy of wheat plant deflection forces obtained using the model was confirmed through theoretical analyses, simulations and experimental measurements. Moreover, deflection tests and posture analysis were performed on the wheat plants for different locations at which the deflection forces were acting and for different plant densities. Experiments focusing on reel operation demonstrated that the deflection forces exerted by the reel rod on wheat plants could be used to predict the number of bent plants, which would subsequently help in wheat biomass estimation. The study found that the influence of the wheat ear on the deflection force significantly increased as the plant deflection increased. The deflection force was most effective at two-thirds of the height of the wheat plant. Moreover, the higher the plant density, the greater the deflection force, which was closely correlated with wheat biomass. A model was established based on the results of the linear regression performed to determine the relationship between the deflection force acting on a wheat plant and its biomass. The model with a determination coefficient of 0.9155 provided a theoretical basis for detecting the feed quantity of the combine harvester. • Analysed the interaction force between the combine harvester reel and wheat plants. • A mechanical model of wheat plant deflection was established. • The method of bending theory of elastic beam with variable cross-section is used. • Prediction of wheat biomass based on interaction force. [ABSTRACT FROM AUTHOR]

The growth of high-quality in vitro potato plants (Solanum stenotomum subsp. stenotomum, Solanum stenotomum subsp. goniocalyx, and Solanum tuberosum subsp. andigena) is affected by multiple biological, operational, and environmental factors. Research on in vitro culture is frequently focused on the species, explant, composition of the culture medium, and incubation conditions, but only limited information is available on the effect of the gas exchange rate and volume of in vitro culture vessels under variable planting densities. In the present study, these factors were evaluated with a set of seven diverse potato landraces. The results were compared to the plants' responses in routinely used in vitro culture vessels, i.e., 13 × 100 mm and 25 × 150 mm test tubes, and GA7® magenta vessels. In vitro potato plants grown in plastic vessels equipped with a HEPA filter delivering a high gas exchange rate developed thicker stems (0.95 mm), a higher total average leaf area (2.51 cm2), increased chlorophyll content in leaves (32.2 ppm), and lower moisture content in their tissues (90.1%) compared to filter systems with lower gas exchange rates. A high planting density of 10 × 10 plants per vessel (360 and 870 mL) negatively affected the average stem width and root length but increased the plant height (3.4 cm). High fluctuations of ion-uptake of NO3−, Ca++, K+, and Na+ were observed between genotypes, with some accessions having a 4.6-times higher Ca++-ion concentration in their tissues (190–234 ppm). The in vitro plants developed more robust stems, longer roots, and larger leaves within in vitro culture vessels equipped with a HEPA filter (high gas exchange rate) compared to the control vessels, in contrast to the chlorophyll content in leaves, which was higher in plants grown in narrow test tubes. Depending on the purpose of the subculture of in vitro plants, their growth and development can be molded using different gas exchange rates, planting densities, and vessel volumes. [ABSTRACT FROM AUTHOR]

The cultivation of sunflower (Helianthus annuus L.) as a cut flower stands out in floriculture due to its aesthetic beauty and commercial value. Understanding how cut sunflower genotypes adapt to different edaphoclimatic regions and management practices is essential to optimize flower quality and productivity. This study aimed to evaluate the effect of plant density and location on the development, growth, and quality of cut sunflower in tropical and subtropical environments. Plant densities of 10, 20, 30, 40, and 50 plants/m2 were evaluated in tropical climate and subtropical climate using a randomized block design in a factorial scheme. Results showed significant differences between locations for plant height, capitulum and stem diameter, final number of leaves, leaf area, leaf area index, phyllochron, and the developmental cycle. Plant density significantly influenced these variables except for plant height and developmental cycle. The interaction between location and plant density was significant only for capitulum diameter and final leaf number. The findings indicate that both planting density and location significantly influence the developmental cycle of cut sunflowers, with lower densities favoring more robust plants at harvest. A density of 30 plants/m2 is recommended for efficient space use without significantly compromising floral stem quality. All produced stems are marketable, suggesting that adjusting planting density can optimize production without compromising quality, adapting to specific regional conditions. [ABSTRACT FROM AUTHOR]

Planting density is an effective strategy for regulating both oat lodging and forage quality. To delve into the regulatory mechanisms of planting density on lodging and oat forage quality, lodging-resistant variety LENA and lodging-sensitive variety QY2 were grown in 2018 and 2019 growing seasons, and four planting densities were implemented: 2.25 × 106 plants/ha (D1), 4.5 × 106 plants/ha (D2), 6.75 × 106 plants/ha (D3), and 9 × 106 plants/ha (D4). At the milk stage, we measured the contents of potassium, calcium, magnesium, silicon, lignin, crude fiber, starch, soluble sugar, and soluble protein in the second and third stem internodes of the plants. The results revealed the lodging-resistant variety LENA demonstrated significantly higher contents of calcium, potassium, silicon, crude fiber, lignin, and lower contents of starch, soluble sugar, and soluble protein (p < 0.01). Similar trends in the physicochemical properties of stem internodes for both oat varieties with increasing planting density. Crude fiber, soluble sugar, magnesium, starch, potassium, and lignin were the key characteristics affecting the lodging coefficient, and variety and planting density affected the lodging coefficient mainly by regulating the synthesis of starch, soluble sugar, and crude fiber. At planting density D3, stem internodes exhibited higher physicochemical properties and a lower lodging coefficient, favoring oat forage production. The results offer a valuable theoretical foundation and practical reference for oat lodging-resistant cultivation. [ABSTRACT FROM AUTHOR]

Appropriate nutrient sources and optimized doses of plant nutrients for space and lunar farming have remained key challenges prompting investigations to sort out biologically viable options including human urine. Therefore, a trial was performed to compare the hydroponic growth of sugar beets using a standard nutrient solution and the same nutrient solution with a 10% replacement of an artificial urine solution that had been concentrated using direct contact membrane distillation (DCMD). The response variables included yield-contributing traits and root parameters (plant height, stem diameter, length and fresh weight of leaf and root, whole plant fresh weight), along with beet characteristics (diameter, length, and fresh weight at harvest). The results revealed that 10% synthetic urine treatment produced significantly taller plants (33%, 3%, and 8% at the 4th, 6th, and 10th week after sowing, respectively) and recorded 52% and 40% greater leaf width at the 4th and 6th weeks, respectively, compared to the control. In contrast, 10% replacement with synthetic urine in the nutrient performed statistically below par compared to the control treatment by producing 9% and 17% lower leaf width at the 8th and 10th weeks, respectively. Additionally, at the harvest, 10% synthetic urine treatment gave taller plants with greater stem length and root length (2.3%, 8.6%, and 59%, respectively) than the control. Moreover, the replacement treatment remained superior by showing higher root weight and stem diameter at harvest but performed below par compared to the control in leaf width and whole plant fresh weight. At harvest, both treatments remained statistically non-significant in terms of beet length, however the control surpassed synthetic urine treatment by yielding 37% and 103% higher width and fresh weight of beets, respectively. Based on recorded findings, it may be inferred that synthetic urine holds potential as a valuable plant nutrient source for producing sugar beets in an indoor hydroponic system, though not comparable in some respects with the control (standardized plant nutrient medium) for some plant measurements. [ABSTRACT FROM AUTHOR]

Conventional in vitro propagation using semisolid Murashige and Skoog (MS) culture systems is costly, labor-intensive, and requires substantial space for large-scale plant production. This study investigated the application of a temporary immersion bioreactor (TIB) system for the micropropagation of the banana cultivar Kluai Numwa Pakchong 50, as a promising platform for economical commercial production. The cultivation parameters affecting plantlet multiplication, including plant growth regulator (PGR) use, explant density, and immersion frequency, were examined. Additionally, the ex vitro acclimatization of well-developed in vitro plantlets was also evaluated. Using liquid MS medium supplemented with 7.5 mg/L 6-benzylaminopurine (BAP) in the TIB system yielded significantly better results than the conventional semisolid MS control system, producing more shoots (5.60 shoots/explant) and leaves (2.80 leaves/explant) with longer shoot length (2.19 cm). Optimal conditions in the TIB system included an inoculum density of five explants per culture vessel and an immersion frequency of once every 6 or 8 h for 2 min. For root induction, 0.5 mg/L indole-3-butyric acid (IBA) proved more effective than 1-naphthaleneacetic acid (NAA). After 30 days of ex vitro acclimatization, plantlets regenerated from the TIB system demonstrated high survival rates, vegetative growth performance, and root formation efficiency comparable to those from the semisolid culture system. These findings establish the TIB system as a promising platform for the mass propagation of the Kluai Numwa Pakchong 50 banana. The protocol developed in this study could potentially be adapted for large-scale production of other banana varieties. [ABSTRACT FROM AUTHOR]

[Objective] To provide theoretical and practical guidance for high yield and lodging resistance of maize cultivation in Sichuan and promote the development of mechanical grain harvesting technology of maize, this study investigated the effects of different sowing dates and densities on stalk characteristics and lodging resistant mechanical properties. [Method] The maize cultivar 'Zhongyu 3' was selected for field experiments including six sowing dates (March 27th, April 6th, April 16th, April 26th, May 6th and May 16th) and two planting densities (6.75 and 8.25X104 plants/hm²). All samples were collected 10 days after physiological maturity of maize to measure stalk lodging rates (root lodging rate and stalk breaking rate), yield, plant agronomic traits (plant height, ear height and coefficient of ear height), basal stem morphology (internode length, internode diameter and internode length-to-diameter ratio (L/D)), quality traits (internode dry weight (DW), dry weight per unit length (DWUL), dry weight per unit volume (DWUV) and stem moisture content (MC)) and mechanical strength indexes including crushing strength (CS), rind penetration strength (RPS) and bending strength (BS) of the third stem internode. [Result] Maize lodging resistance was significantly affected by sowing date and planting density. With the delay of sowing date, stalk lodging rate, root lodging rate and stalk breaking rate decreased first and then increased, while maize yield decreased gradually. The plant height, ear height, the third internode length and ratio of length-to-diameter increased significantly, while DW, DWUL and DWUV of the third internode increased after initial decreases.On the contrary, the third internode MC and mechanical strength indexes increased first and then decreased significantly. When the sowing date was delayed from April 26th to May 6th, internode morphology, quality traits, mechanical strength and stalk lodging rate reached the maximum or minimum, respectively. Increasing density further promoted the increasing or decreasing effects, which led to significant increases of stalk lodging rate.Correlation analysis showed that stalk lodging rates at different sowing dates were significantly affected by rainfall and wind after physiological maturity, and it was significantly correlated with L/D, DW, DWUL and RPS, CS and BS of the third internode. The change in stalk mechanical strength was the main reason of lodging rate variations, and the changes in DWUL and L/D were the main factors affecting mechanical properties of lodging resistance. [Conclusion] Optimizing planting density and sowing date could achieve high population yield and lodging resistance. It was suggested to sow spring maize in mid-to-late April and summer maize in early May with planting density of 6.75X104 plants/hm² for coordinated high yield and lodging resistance. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the influence of boom height above a crop stand and the spacing between nozzles and diffusers in an over-row sprayer on the uniformity of the horizontal spray distribution and the uniformity of the air velocity distribution. The experimental setup involved a prototype over-row sprayer equipped with a boom with a working width of 8 m and ten air diffusers with spray nozzles. Air diffusers were connected to one or two nozzles each, and they were installed on the boom at intervals of 60, 80, and 90 cm. Terminal airflow velocity at a canopy is determined by the height of a sprayer boom and the diffuser spacing, ranging from around 2 m s–1 to around 27 m s–1. The sprayer boom should be positioned at a height of 50 cm above a crop stand due to the difference between the minimum and maximum airflow velocities. The horizontal spray distribution was more uniform when the sprayer was equipped with hollow-cone nozzles instead of flat-fan nozzles; hollow-cone nozzles should be applied if the distance between nozzles needs to be adjusted to the row width and row spacing. The analyzed coefficients did not exceed 10% when the boom was positioned 50 cm above the crop stand and when the nozzles were spaced 80 cm apart, which suggests that, in this configuration, sprayers equipped with hollow-cone nozzles can also be applied to close-grown crops. [ABSTRACT FROM AUTHOR]

Recently classified as a unique species by the IUCN, African forest elephants (Loxodonta cyclotis) are critically endangered due to severe poaching. With limited knowledge about their ecological role due to the dense tropical forests they inhabit in central Africa, it is unclear how the Afrotropics are influenced by elephants. Although their role as seed dispersers is well known, they may also drive large‐scale processes that determine forest structure through the creation of elephant trails and browsing the understory, allowing larger, carbon‐dense trees to succeed. Multiple scales of lidar were collected by NASA in Lopé National Park, Gabon from 2015 to 2022. Utilizing two airborne lidar datasets in an African forest elephant stronghold, detailed canopy structural information was used in conjunction with elephant trail data to determine how forest structure varies on and off trails. Forest along elephant trails displayed different structural characteristics than forested areas off trails, with lower canopy height, canopy cover, and different vertical distribution of plant density. Less plant area density was found on trails at 1 m in height, while more vegetation was found at 12 m, compared to off trail locations. Trails in forest areas with previous logging history had lower plant area in the top of the canopy. Forest elephants can be considered as "logging light" ecosystem engineers, affecting canopy structure through browsing and movement. Both airborne lidar scales were able to capture elephant impact along trails, with the high‐resolution discrete return lidar performing higher than waveform lidar. [ABSTRACT FROM AUTHOR]

Compared to agricultural environments, afforestation sites are more complex, often presenting issues such as undulating and uneven terrain. These conditions lead to instability in hole digging depth and plant spacing during continuous movement, and the hole shape may not meet expectations. Additionally, the hydraulic system exhibits slow response speed and long steady-state time, affecting the quality of sapling planting. To address these issues, this paper designs an intelligent planting control system for intermittent hole digging under continuous dynamic movement, based on a large tree planter. The focus is on studying the dynamic accuracy of the hole digging cylinder to resolve the instability of plant spacing and planting depth in actual planting processes. Firstly, a motion trajectory model of the intermittent hole digging mechanism is established to obtain the relationship between the displacement trajectory of the rotating cutter and the displacements of the floating cylinder and the hole digging cylinder. Secondly, a mathematical model of the electro-hydraulic servo system is established to control the dynamic accuracy of the hole digging operation. Finally, a Simulink simulation model of the system is established to analyze the performance indicators of the hydraulic system during operation using step and sinusoidal excitation signals. The test results show that the displacement of the hydraulic piston rod can ensure a linear extension trend within the range of 0 to 0.4 m, and the extension distance of the hole digging cylinder in the planting system is 0 to 0.35 m, ensuring linear change within this stroke. When the system's extension command is 1 V, the actual output is 0.6 m, with a relative error of less than 10% compared to the simulation value, indicating that the control strategy can effectively improve the dynamic performance of the system. When the hydraulic system is in a steady-state extension state at 50 to 58.6 s, the relative error with the simulation value is 7.3%, meeting the "double ten indicators" requirement. The research results clearly verify the superior performance of the proposed intelligent control system, and the proposed control strategy has great potential in practical applications, promising to improve afforestation quality by stabilizing planting spacing and planting depth. [ABSTRACT FROM AUTHOR]

Traditional oak silviculture is costly due to high initial planting density required to obtain management goals of producing high quality timber. New methods therefore reduce the initial planting density and use a planting pattern that allows the inclusion of naturally regenerated trees of other species. The study presents the results of a 13-year experiment on the growth and quality of sessile oak planted in traditional and three alternative planting patterns. We hypothesized that increasing of initial spacing and use of natural regeneration to compensate for lower intra-specific competition does not deteriorate growth and quality parameters of oak. Breast height diameter, height, slenderness, height of the first live branch, diameter of the thickest branch, stem shape and potential future crop oak trees (PFCT) were measured and analysed. The local competition of admixture species was estimated on the basis of the relationship between the height of the oak and the height of admixture trees in its close proximity. The type of planting pattern had no significant effect on oak diameter, but oak height was greater in the traditional pattern than in alternative patterns. Height of the first live branch was the only qualitative trait that differed significantly between the compared planting patterns. The probability of an oak being selected as a PFCT was similar in traditional and alternative patterns, but PFCT absolute number was increasing with an increase of oak planting density. Analysis of competition of admixture species in alternative methods shows that it can reduce height, diameter and stability of oaks. On the other hand, the probability of trees being selected as a PFCT increases significantly with increasing interspecific competition. We conclude that, with controlled competition and at least moderate natural regeneration, the alternative planting patterns can produce oaks with similar growth and quality to those in the traditional pattern. [ABSTRACT FROM AUTHOR]

Precise information on strawberry fruit distribution is of significant importance for optimizing planting density and formulating harvesting strategies. This study applied a combined analysis of kernel density estimation and nearest neighbor techniques to estimate fruit distribution density from YOLOdetected strawberry images. Initially, an improved yolov8n strawberry object detection model was employed to obtain the coordinates of the fruit centers in the images. The results indicated that the improved model achieved an accuracy of 94.7% with an mAP@0.5~0.95 of 87.3%. The relative error between the predicted and annotated coordinates ranged from 0.002 to 0.02, demonstrating high consistency between the model predictions and the annotated results. Subsequently, based on the strawberry center coordinates, the kernel density estimation algorithm was used to estimate the distribution density in the strawberry images. The results showed that with a bandwidth of 200, the kernel density estimation accurately reflected the actual strawberry density distribution, ensuring that all center points in high-density regions were consistently identified and delineated. Finally, to refine the strawberry distribution information, a comprehensive method based on nearest neighbor analysis was adopted, achieving target area segmentation and regional density estimation in the strawberry images. Experimental results demonstrated that when the distance threshold ϵ was set to 600 pixels, the correct grouping rate exceeded 94%, and the regional density estimation results indicated a significant positive correlation between the number of fruits and regional density. This study provides scientific evidence for optimizing strawberry planting density and formulating harvesting sequences, contributing to improved yield, harvesting efficiency, and reduced fruit damage. In future research, this study will further explore dynamic models that link fruit distribution density, planting density, and fruit growth status. [ABSTRACT FROM AUTHOR]

The optimization of artificial pollination is crucial in breeding programs for allogamous plants. In maize, achieving a balance between the labor-intensive nature of controlled pollinations and the need for large-scale production of hybrid seeds, along with considerations of germinability and pollen production, determines the success of genetic improvement programs. Breeding programs in maize have resulted in a reduction in the number of tassel branches to increase light interception and plant density in production fields. However, despite this genetic improvement, the decreased pollen production per plant has raised critical concerns regarding pollination and subsequent ear filling, especially under adverse environmental conditions. The aim of this work was the analysis of factors that can contribute to increasing the efficiency of controlled pollination in maize. The data obtained showed that pollen diameter, flavonoid, and phenolic acid content do not influence the percentage of germination and therefore the efficiency of pollination. The quantity of pollen is a central factor in ensuring the efficiency of controlled pollinations, and the data obtained by comparing traditional varieties with modern hybrids of maize showed that an increase in pollen production is determined by the increase in branching of the male inflorescence. Furthermore, we propose the use of a "smart" pollination method to make this step in maize breeding programs easier and faster. [ABSTRACT FROM AUTHOR]

To address the issues of high labor intensity, excessive manpower requirements, low planting spacing qualification rates, low planting depth qualification rates, and low operational efficiency associated with sweet potato transplanting, a sweet potato seedling belt transplanter has been designed. This machine can perform multiple processes: precision tillage and ridge shaping, orderly seedling feeding from rolls, the efficient separation of seedlings from the belt, flexible gripping and shaping, precise soil covering and the mechanism of exposing seedling tips. A three-factor, three-level orthogonal test was carried out using the forward speed of the machine, the pitch of the screw belt and the rotational speed of the screw as the influencing factors of the performance test, and the qualified rate of planting spacing and the qualified rate of planting depth as the evaluation indexes. The test results indicated that the significance order of the factors affecting the qualification rate for planting spacing with the optimal combination of factors was as follows: a forward speed of 0.3 m·s−1, a ribbon spacing of 60 mm, and a screw speed of 160 rpm. Field trials confirmed that under optimal conditions, the average qualification rate for planting spacing was 90.37%, meeting relevant technical standards and agronomic requirements. [ABSTRACT FROM AUTHOR]

In peanut cultivation in the Tokachi region of Hokkaido, Japan, it is essential to complete the harvest by early October to prevent frost damage. Therefore, cultivation methods that can accelerate the flowering period are necessary. It is understood that planting density can influence the timing of flowering, with crops often flowering earlier at higher densities. This study aimed to investigate whether growing peanuts at higher densities could advance the flowering period and, consequently, enhance yield. The Japanese peanut variety, Tachimasari, was cultivated in 2022 and 2023 at a conventional planting density of 5.8 plant m−2 (D5.8) and at density conditions of 8.7 plant m−2 (D8.7) and 11.6 plant m−2 (D11.6). The D8.7 and D11.6 plants reached the peak of flowering 2.8 and 5.1 days earlier, respectively, and the end of flowering 3.7 and 8.0 days earlier than the D5.8 plants. Although the total number of flowers was higher in D5.8, pod fertility was greater in D8.7 and D11.6, where plants were able to reduce the occurrence of ineffective flowers and immature pods. Consequently, higher seed yields were observed in D8.7 (2709 kg ha−1) and D11.6 (2754 kg ha−1), where lower individual productivity was offset by higher planting densities, compared to the conventional density condition of D5.8 (2169 kg ha−1). [ABSTRACT FROM AUTHOR]

A fundamental assumption in plant science posits that leaf air spaces remain vapor saturated, leading to the predominant view that stomata alone control leaf water loss. This concept has been pivotal in photosynthesis and water-use efficiency research. However, recent evidence has refuted this longstanding assumption by providing evidence of unsaturation in the leaf air space of C3 plants under relatively mild vapor pressure deficit (VPD) stress. This phenomenon represents a nonstomatal mechanism restricting water loss from the mesophyll. The potential ubiquity and physiological implications of this phenomenon, its driving mechanisms in different plant species and habitats, and its interaction with other ecological adaptations have. In this context, C4 plants spark particular interest for their importance as crops, bundle sheath cells' unique anatomical characteristics and specialized functions, and notably higher water-use efficiency relative to C3 plants. Here, we confirm reduced relative humidities in the substomatal cavity of the C4 plants maize, sorghum, and proso millet down to 80% under mild VPD stress. We demonstrate the critical role of nonstomatal control in these plants, indicating that the role of the CO2 concentration mechanism in CO2 management at a high VPD may have been overestimated. Our findings offer a mechanistic reconciliation between discrepancies in CO2 and VPD responses reported in C4 species. They also reveal that nonstomatal control is integral to maintaining an advantageous microclimate of relatively higher CO2 concentrations in the mesophyll air space of C4 plants for carbon fixation, proving vital when these plants face VPD stress. [ABSTRACT FROM AUTHOR]

Introduction: The stay-green (SG) or delayed leaf senescence enables crop plants to maintain their green leaves and photosynthetic capacity for a longer time after flowering. It is considered an important trait in maize breeding, which has contributed to gain in grain yield of modern varieties. It has been also used to improve the tolerance to drought and deficiencies in nitrogen fertilization (NF). However, the objective of this study is to evaluate the influence of water irrigation (WI), NF, and plant density (PD) on SG and the effect of SG on agronomic traits in maize. Methods: Four SG lines and four non-stay-green (NSG) lines were evaluated in four contrasting environments under two WI, three NF, and two PD levels. Results and discussion: As expected, the chlorophyll content of leaves at 45 days after flowering (Chlo45) was, on average, higher in the SG group of lines. The difference in Chlo45 between the SG and NSG genotypes was consistent across WI, NF, and PD and the environments. This is indicative that internal or developmental factors were more important than external signals in controlling the senescence. The effect of SG increasing thousand-kernel weight, stover yield at harvest, or moisture was not influenced by WI, NF, or PD but was altered by the background environment. Our results have implications for the application of SG as a secondary trait for enhancing abiotic stress tolerance. Future studies could consider a wider range of environmental conditions to assess the performance of SG traits under different climatic and soil conditions. [ABSTRACT FROM AUTHOR]

Bioengineered/genome-edited carbon capture and sequestration (BE/GEd-CCS) crops are being developed to mitigate climate change. This paper explores how technology, regulation, funding, and social implications, could shape the development and deployment of these crops. We conclude that some of the technological efforts to create BE/GEd-CCS crops may work. Still, stakeholders must agree on generally accepted methods of measuring how much carbon is captured in the soil and its value. The regulatory space for BE/GEd-CCS crops remains fluid until the first crops are reviewed. BE/GEd-CCS crops have received considerable initial funding and may benefit financially more from other federal programs and voluntary carbon markets. BE/GEd-CCS crops may continue perpetuating social equity concerns about agricultural biotechnology due to a lack of oversight. We argue that stakeholders need to pursue a multidisciplinary view of BE/GEd-CCS crops that draw in varying perspectives for effective development and deployment. Communication is needed between researchers and policymakers involved in either developing BE/GEd-CCS crops or developing voluntary carbon markets. We argue for the start of a conversation both across disciplines and between researchers and policymakers about the development and deployment of BE/GEd-CCS crops. [ABSTRACT FROM AUTHOR]

Pollinator diversity and abundance are under direct threat from human activities. Despite societal dependence on pollinators for crop production, humankind continues to drive pollinator declines through agricultural intensification and urbanisation. Urban environments can provide refuge to some pollinators. There is a need, however, to understand how pollinator communities can be supported in these areas while also considering human needs. Public green spaces provide a promising avenue to target plant–pollinator conservation measures in an urban setting due to their large area, high abundance and low plant–pollinator biodiversity. We used a paired design to compare the plant community, pollinator community and plant–pollinator interactions of (i) public urban green spaces enhanced with wildflower meadows and pollinator‐friendly ornamental plantings to (ii) control unenhanced urban green spaces. The planting types within enhanced sites were also separately compared. Our results show that not only was the diversity of the overall pollinator community higher in enhanced than control sites, but also the complexity of some wild Hymenoptera and the abundance of Diptera pollinator groups. The negative impact of urbanisation on some pollinator groups was reduced in enhanced sites compared with control sites. Planting both pollinator‐friendly ornamental plants and wildflower meadows significantly increased the visits from Diptera and the diversity in the plant–pollinator community compared with wildflower plantings alone. Our results suggest that enhancing public spaces for pollinators has positive effects on key groups and can help mitigate the impacts of urbanisation. Non‐native ornamental plants can also play a role in enhancing green spaces for pollinators while maintaining their recreational functions. This supports a mixed‐planting approach for improving public green spaces in urban areas for both people and nature. [ABSTRACT FROM AUTHOR]

Tiller angle is a key agricultural trait that establishes plant architecture, which in turn strongly affects grain yield by influencing planting density in rice. The shoot gravity response plays a crucial role in the regulation of tiller angle in rice, but the underlying molecular mechanism is largely unknown. Here, we report the identification of the BIG TILLER ANGLE2 (BTA2), which regulates tiller angle by controlling the shoot gravity response in rice. Loss‐of‐function mutation of BTA2 dramatically reduced auxin content and affected auxin distribution in rice shoot base, leading to impaired gravitropism and therefore a big tiller angle. BTA2 interacted with AUXIN RESPONSE FACTOR7 (ARF7) to modulate rice tiller angle through the gravity signaling pathway. The BTA2 protein was highly conserved during evolution. Sequence variation in the BTA2 promoter of indica cultivars harboring a less expressed BTA2 allele caused lower BTA2 expression in shoot base and thus wide tiller angle during rice domestication. Overexpression of BTA2 significantly increased grain yield in the elite rice cultivar Huanghuazhan under appropriate dense planting conditions. Our findings thus uncovered the BTA2‐ARF7 module that regulates tiller angle by mediating the shoot gravity response. Our work offers a target for genetic manipulation of plant architecture and valuable information for crop improvement by producing the ideal plant type. [ABSTRACT FROM AUTHOR]

Nigella sativa, also known as black cumin, is esteemed for its rich reservoir of health-benefitting phytoconstituents nestled within its seeds. The composition of its seeds can be influenced by factors such as genotype diversity and agricultural practices. Understanding these dynamics is important for maximizing the nutritional and medicinal attributes of the seeds. This study investigated how different genotypes, growing densities, and sowing times affect oil yield and phytoconstituents of Nigella seeds in Northern Australia. The aim was to find the optimal combination of these factors to maximize desirable compounds. Our findings revealed variability in oil yield and phytoconstituents among different genotypes, growing densities, and sowing times. No single genotype stood out as having elevated levels of all desired compounds. For instance, genotype AVTKS#5 had high total phenolic content (TPC) and antioxidant capacity, while AVTKS#8 and AVTKS#7 excelled in thymoquinone (TQ) and polyunsaturated fatty acids (PUFAs) and monounsaturated fatty acids (MUFAs), respectively. Planting density had a nuanced impact, with no significant effect on oil yield and CUPRAC values, but higher densities decreased TPC, FRAP, and TQ. Interestingly, seeds cultivated at 20 and 30 plants/m2 had higher ratios of MUFAs/SFAs, PUFAs/SFAs, and (MUFAs + PUFAs)/SFAs, indicating the importance of planting density in shaping fatty acid profiles. Sowing times also had a noticeable effect, with late sowing leading to a decrease in oil yield from 19% to 14%. May-sown seeds had higher TPC, FRAP, CUPRAC, and fatty acid ratios, while TQ levels peaked in June-sown seeds. Our study highlighted positive correlations among TPC, FRAP, CUPRAC, and TQ, emphasizing their collective contribution to the nutritional and medicinal potency of Nigella seeds. Fatty acids, on the other hand, showed no significant correlation with these parameters, indicating independent regulation. In summary, our comprehensive analysis provides insights into the factors (genotype and agronomic practice) that shape the phytochemical profile of Nigella seeds, and suggests better genotype, planting density, and time of sowing for the cultivation and quality production. [ABSTRACT FROM AUTHOR]

Asian corn borer (ACB), Ostrinia furnacalis, is an important agricultural pest affecting maize production in southwestern China, but knowledge of the toxic effect of Bt maize on the pest has been insufficient until now. In this study, we determined the susceptibility of ACB to Cry1Ab, Vip3Aa, and their complex proteins and evaluated the efficacy of Chinese domestic Bt-(Cry1Ab+Vip3Aa) maize ("DBN3601T" event) against the pest in Yunnan Province of southwestern China. The susceptible bioassay indicated that the LC50 values of the Cry1Ab and Cry1Ab+Vip3Aa proteins expressed by the Bt maize varieties against ACB larvae were 51.42 and 46.85 ng/g, respectively; however, the ACB larva was insensitive to the Vip3Aa protein. The Cry1Ab+Vip3Aa protein contents in V6–V8 leaves, VT tassels, R1 silks, R2 kernels, R3 stalks and R3 cobs of the Bt-(Cry1Ab+Vip3Aa) maize were 114.20, 30.69, 3.77, 8.92, 11.09 and 10.99 μg/g, respectively. The larval feeding test indicated that the Bt-(Cry1Ab+Vip3Aa) maize was more toxic to the early instar larvae, and the survival time of larvae fed on the leaves was the shortest, while it survived the longest on stalks. The identification of maize resistance levels in the field showed that both larval density and plant damage score of Bt-(Cry1Ab+Vip3Aa) maize were significantly lower than those in conventional maize. It is concluded that the Bt-(Cry1Ab+Vip3Aa) maize can be used for control of the ACB in southwestern China. [ABSTRACT FROM AUTHOR]

Factors such as the selection of cultivars and the planted density affect the development and yield of peanuts (Arachis hypogaea L.). This study's objective was to evaluate peanut cultivars' agronomic behavior under three planting densities in the northeast of Peru. The design used was randomized complete blocks (DBCAs) with a bifactorial arrangement 4A × 3B (factor A, peanut cultivars; factor B, planting densities), forming 12 treatments with three replications per block. The results revealed that T3 (Huayabamba cultivar + density of 30 × 50 cm) stood out, presenting the most favorable means in the number of pods (16 pods), number of seeds per pod (five seeds), height at 90 days (22.7 cm), and yield (1850 kg/ha). Empty pods did not show significant differences between treatments. T8 (Chivita cultivar + density of 20 × 50 cm) indicated the highest number of branches (six branches); in the weight of 100 seeds, the Rojo Tarapoto cultivar was the most encouraging, adapting optimally to the three densities. In addition, T7 (chivita cultivar + density of 10 × 50 cm) showed the shortest days at flowering and harvest, with 64 and 134 days. The study showed that T3 was the most efficient in pod and seed production, making it crucial to optimizing peanut yield. [ABSTRACT FROM AUTHOR]

The optimization of plant density plays a crucial role in cotton production, and deficit irrigation, as a water-saving measure, has been widely adopted in arid regions. However, regulatory mechanisms governing nitrogen absorption, transportation, and nitrogen use efficiency (NUE) in cotton under deficit irrigation and high plant density remain unclear. To clarify the mechanisms of N uptake and NUE of cotton, the main plots were subjected to three irrigation amounts based on field capacity (Fc): (315 [W1, 0.5 Fc], 405 [W2, 0.75 Fc, farmers' irrigation practice], and 495 mm [W3, 1.0 Fc]). Subplots were planted and applied at three densities: (13.5 [M1], 18.0 [M2, farmers' planting practice], and 22.5 [M3] plants m−2). The results revealed that under low-irrigation conditions, the cotton yield was 5.1% lower than that under the farmer's irrigation practice. In all plant densities and years, the nitrogen uptake of cotton increased significantly with the increase in irrigation. However, excessive irrigation resulted in nitrogen accumulation and migration, mainly concentrated in the vegetative organs of cotton, which reduced the NUE by 9.2% compared with that under farmers' irrigation practice. Concerning the interaction between irrigation and plant density, under low irrigation, the nitrogen uptake of high-density planting was higher, and the yield of seed cotton was only 2.9% lower than that of the control (the interaction effect of farmers' irrigation × plant density), but the NUE was increased by 10.9%. Notably, with the increase in irrigation amount, the soil nitrate nitrogen at the 0–40 cm soil layer decreased, and high irrigation amounts would lead to the transfer of soil nitrate nitrogen to deep soil. With the increase in plant density, the rate of nitrogen uptake and the amount of nitrogen uptake increased, which significantly reduced the soil nitrate nitrogen content. In conclusion, deficit irrigation and high plant density can improve cotton yield and NUE. We anticipate that these findings will facilitate optimized agricultural management in areas with limited water. [ABSTRACT FROM AUTHOR]