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The document titled "PP 1/336 (1) Efficacy evaluation of herbicides used with mechanical weeders" outlines the standards for conducting field trials to evaluate the efficacy of herbicides in combination with mechanical weeders. The standard specifies that herbicides used with other non-chemical approaches or in band applications are outside its scope. It provides detailed guidelines on experimental conditions, trial design, application of treatments, assessment methods, and reporting of results. The document emphasizes the importance of considering crop safety, weed control, and selectivity in evaluating the efficacy of herbicides with mechanical weeders. [Extracted from the article]

The document titled "PM 9/32 (1) Solanum carolinense" from the EPPO Bulletin describes the control procedures for monitoring, containing, and eradicating Solanum carolinense, a perennial herb native to North America. The species is considered a major agricultural problem due to its weedy attributes and negative impact on crop yield, livestock, and host to crop diseases and pests. The document outlines the importance of regional cooperation, surveillance, eradication, and containment measures to prevent the further spread of this pest. It also provides detailed information on monitoring, eradication, and containment strategies, including the use of herbicides, mechanical control, mowing, and cultural control methods. [Extracted from the article]

The document titled "PP 1/331 (1) Principles of efficacy extrapolations for major uses" outlines the principles to be followed when considering effectiveness and crop safety extrapolations of plant protection products applied for major uses. The aim is to reduce the need for trial data on individual major crop and major pest situations while maintaining appropriate data sets. The document provides guidance for regulatory authorities and applicants in the context of product registration and does not cover plant growth regulators or extrapolations of identical uses between different formulations of the same product. It also discusses specific effectiveness extrapolations for fungicides, insecticides or acaricides, and herbicides, with decision-making schemes provided in the appendix. [Extracted from the article]

Introduction: Throughout domestication, crop plants have gone through strong genetic bottlenecks, dramatically reducing the genetic diversity in today's available germplasm. This has also reduced the diversity in traits necessary for breeders to develop improved varieties. Many strategies have been developed to improve both genetic and trait diversity in crops, from backcrossing with wild relatives, to chemical/radiation mutagenesis, to genetic engineering. However, even with recent advances in genetic engineering we still face the rate limiting step of identifying which genes and mutations we should target to generate diversity in specific traits. Methods: Here, we apply a comparative evolutionary approach, pairing phylogenetic and expression analyses to identify potential candidate genes for diversifying soybean (Glycine max) canopy cover development via the nuclear auxin signaling gene families, while minimizing pleiotropic effects in other tissues. In soybean, rapid canopy cover development is correlated with yield and also suppresses weeds in organic cultivation. Results and discussion: We identified genes most specifically expressed during early canopy development from the TIR1/AFB auxin receptor, Aux/IAA auxin co-receptor, and ARF auxin response factor gene families in soybean, using principal component analysis. We defined Arabidopsis thaliana and model legume species orthologs for each soybean gene in these families allowing us to speculate potential soybean phenotypes based on well-characterized mutants in these model species. In future work, we aim to connect genetic and functional diversity in these candidate genes with phenotypic diversity in planta allowing for improvements in soybean rapid canopy cover, yield, and weed suppression. Further development of this and similar algorithms for defining and quantifying tissue- and phenotype-specificity in gene expression may allow expansion of diversity in valuable phenotypes in important crops. [ABSTRACT FROM AUTHOR]

Two independent greenhouse experiments were conducted in December 2020 and July 2021 in Davis, CA to characterize Echinochloa crus‐galli (L.) P. Beauv., Echinochloa colona (L.) Link, Echinochloa oryzicola (Vasinger) Vasinger and Echinochloa walteri (Pursh) A. Heller found in California rice systems based on their morphological traits. Phenotypic data was collected on 10 vegetative traits including plant height, number of tillers, flag leaf length, flag leaf width, flag leaf angle, the colour of leaf sheath, leaf blade colour, internode colour, node colour, growth habit and nine reproductive traits including number of days to heading, number of panicles, length of panicle, length of panicle branches, seeds per panicle, panicle weight, seed colour, awn length and awn pattern. High plasticity was observed in all species characterized in both experiments for both vegetative and reproductive traits, indicating potential inter‐specific hybridization. Awn length, days to heading, length of the panicle, length of the panicle branches, plant height, flag leaf angle, and growth habit were significantly higher in the fall experiment for all species indicating photoperiod could play a role in the expression of these traits. Also, high variation was observed for plant height, number of tillers, awn length, panicle weight, seeds/panicle, length of panicle branch, and number of panicles for all species in both experiments. The results from this study indicate morphological diversity currently present in Echinochloa species could contribute to their adaptation to selection pressure imposed by different management tools in California, emphasizing the need for a diversified management approach to effectively control this weed species. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity can alter traits that are crucial to population establishment in a new environment before adaptation can occur. How often phenotypic plasticity enables subsequent adaptive evolution is unknown, and examples of the phenomenon are limited. We investigated the hypothesis of plasticity-mediated persistence as a means of colonization of agricultural fields in one of the world's worst weeds, Raphanus raphanistrum ssp. raphanistrum. Using non-weedy native populations of the same species and subspecies as a comparison, we tested for plasticity-mediated persistence in a growth chamber reciprocal transplant experiment. We identified traits with genetic differentiation between the weedy and native ecotypes as well as phenotypic plasticity between growth chamber environments. We found that most traits were both plastic and differentiated between ecotypes, with the majority plastic and differentiated in the same direction. This suggests that phenotypic plasticity may have enabled radish populations to colonize and then adapt to novel agricultural environments. [ABSTRACT FROM AUTHOR]

Weed control in container-grown ornamentals can be improved by careful herbicide selection. Four studies were conducted in greenhouses at Oregon State University to improve the understanding of how differences in the mode of action and formulation of herbicides can affect bryophyte control efficacy and crop safety. Granular (G) formulations of pendimethalin and indaziflam were compared with sprayable liquid (L) formulations of pendimethalin, indaziflam, and dimethenamid-p as well as with a nontreated control on four perennial container-grown ornamentals. Indaziflam in the L formulation performed better than that in the G formulations for controlling hairy bittercress up to 20 weeks after the initial treatment. Dimethenamid-p was more effective than indaziflam for liverwort and moss control. Pendimethalin in the G formulation less effectively controlled hairy bittercress than the L formulation did, but it performed better against moss during a second study. The L formulation of indaziflam injured Japanese pachysandra and boxwood and reduced root and shoot growth by 10% to 29%. Dimethenamid-p provided excellent control of the weed species tested and was safe for the crops, indicating its potential use as an alternative to hand-weeding in greenhouses. [ABSTRACT FROM AUTHOR]

California is the nation's primary producer of almonds, pistachios, and walnuts, and an important producer of rice. Because of California's diverse cropping systems, off-target herbicide drift can be a considerable problem, particularly from aerial applications that are commonly used in flooded rice production systems. Triclopyr is an auxin-mimic type herbicide that has been commonly used in rice for many years for control of broadleaf weeds and the industry is familiar with symptoms of off-target triclopyr drift. Florpyrauxifen-benzyl is a newly registered auxin-mimic herbicide in California rice with activity on key weeds and is being rapidly adopted. Although symptoms typically are similar among auxinic herbicides, it is important to understand subtle differences and risks among these herbicides as stewardship for newly registered products. This research was conducted in 2020 and 2021 to determine the relative sensitivity of almond, pistachio, and walnut trees to simulated drift rates of florpyrauxifen-benzyl and triclopyr as well as characterize and compare symptoms caused by these two herbicides. The fractional herbicide rates tested were 1/200X, 1/100X, 1/33X, and 1/10X of the florpyrauxifen-benzyl use rate of 29.4 g·ha-1 a.i. and 1/200X, 1/100X, and 1/33X of the triclopyr use rate of 420.3 g·ha-1 a.e. Florpyrauxifen-benzyl and triclopyr herbicides were applied directly to one side of the canopy of 1- to 2-year-old almond, pistachio, and walnut trees. The general symptoms of florpyrauxifen-benzyl and triclopyr were chlorosis, chlorotic spots, leaf curling, leaf narrowing, leaf distortion, leaf malformation, leaf crinkling, shoot curling, stem coloring, stunting, terminal bud death, and twisting. The florpyrauxifen-benzyl and triclopyr injury symptoms were compared at the same fractional rates and found to be similar to each other. The herbicide injury was observed on the entire pistachio canopy, particularly on developing leaves and terminal buds. In contrast, injury symptoms on almond and walnut were more apparent on the side of the canopy to which the herbicides were applied. Symptom severity peaked at 14 days after treatment with the 1/10X florpyrauxifen-benzyl rate, when the visible injury was 16%, 48%, and 78% on almond, walnut, and pistachio, respectively. Although almond and walnut symptoms from the 1/10X florpyrauxifen-benzyl rate remained visible longer than all other treatments, all trees gradually recovered throughout the growing season. In contrast, pistachio trees did not recover fully and had injury symptoms that persisted for the remainder of the treatment year and at leaf-out the following spring. When drift occurs, it is typically at rates below 1/100X up to 1/33X of herbicide use rates. This research suggested that proper herbicide drift management practices and application precautions are likely to minimize the risk of significant injury from florpyrauxifen-benzyl drift to almond and walnut because of low injury symptoms at the typical drift rates. However, extra precautions may be needed if there are nearby pistachio orchards. [ABSTRACT FROM AUTHOR]

We studied the allelopathic effects of mulch and aqueous extracts of Rice (Oryza sativa L.) straw and on growth of 8-weeds: Phalaris minor L., Cynodon dactylon L., Chenopodium album L., Rumex denticulate L., Anagalis arvensis L., Melilotus spp L., Parthenium hysterophorus L. and Cyperus rotundus (L.) was analyzed. Rice straw mulch at 4.0 t/ha and rice aqueous solution (10 g/L) spray significantly reduced these weeds density (Number/m2) (54, 55, 66, 79, 85, 73, 54 and 39 during 2020-21) respectively, than control. Rice straw mulch 4 t/ha followed by (metsulfuron methyl 4 g a.i./ha + clodinafop propargyl 60 g a.i./ha) and clodinafop propargyl 75 % of 60 g a.i./ha + rice aqueous solution (10 g/L) spray significantly reduced the density of test weeds. Density of grass weeds decreased in zero-till, but broad leaved weeds decreases in conventional tillage. Wheat growth (dry matter accumulation: g/plant), number of tillers per m, leaf area index (LAI) and yield) significantly increased by rice straw mulch at 4 t/ha followed by rice aqueous solution (10 g/L) spray than control. [ABSTRACT FROM AUTHOR]

Amaranthus palmeri S. Watson is a problematic weed that has been encountered almost all over the world because of its stronger adaptability, which causes huge economic losses and local plant diversity decline. As an invasive plant, A. palmeri has been found throughout China. We thus make a code system to describe the phenological growth process of A. palmeri according to the extended BBCH scale to better understand the phenological growth of this weed in China. The growth process of A. palmeri was divided into vegetative growth phases and reproductive growth phases. The vegetative growth phases are composed of seed germination (0), leaf development (1), formation of side shoots (2) and main stem elongation (3). Likewise, the reproductive growth phases include inflorescence emergence (5), blooming (6), fruit development (7), seed maturity (8) and senescence (9). Based on the extended BBCH scale, the first digit stands for the primary growth stages, and the third digit represents the secondary growth stages. In particular, the second digit defines the growth progress: the number 0, means the vegetative growth phases, and the number 1 stands for the reproductive growth phases. Owing to the fact that its seed can germinate multiple times within a year, a general illustration of the phenological development stages of A. palmeri germinating in different months was provided here to describe the growth dynamic characteristic at different times. These data are of great significance to develop effective strategies for weed control and management of A. palmeri. [ABSTRACT FROM AUTHOR]

Growth in demand for organic small grains has increased interest in producing certified organic crops in the semiarid US Pacific Northwest. The region is well‐suited for small grain production, and there is a strong market for organic food products on the US West Coast. However, many growers encounter significant and persistent challenges with weed management, particularly management of perennial weeds such as Canada thistle [Cirsium arvense (L.) Scop.] and field bindweed (Convolvulus arvensis L.), but also common winter and spring annual grass weeds including cheatgrass (Bromus tectorum L.) and wild oat (Avena fatua L.). Coupled with the need to minimize soil disturbance, weed management can become nearly intractable and production limiting. From 2004 to 2024, several short and intermediate studies have been conducted to assess weed control tactics and crop rotation effects on weed management. Lessons learned include incorporating alfalfa (Medicago sativa L.) and spring barley (Hordeum vulgare L.) into rotations for suppression of field bindweed, or alfalfa and winter triticale (x Triticosecale Wittmack) for suppression of Canada thistle. Optimization of cultural inputs, particularly seeding rate, are critical for each crop in rotation. Animal integration and new crops such as quinoa (Chenopodium quinoa Willd.) are alternatives to conventional crops and potentially profitable. Incorporation of precision mechanical and chemical systems is feasible in narrow‐row cereals, and when combined with crop rotation, it could reduce or eliminate the need for repeated transitions back to convention production for organic growers. Core Ideas: Weed management for organic cereal production in the Pacific Northwest requires the use of "all of the above" approach.Crop rotation, diversification, and optimized cultural inputs are essential for the management of perennial weeds.The combination of mechanical weed control and precision guidance systems is essential for organic weed management.Organic herbicides are economically feasible to use when combined with an optical sensor sprayer system. [ABSTRACT FROM AUTHOR]

While the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), has invaded Asia, whether it uses local weeds as alternative hosts remains understudied. This knowledge gap is significant as alternative hosts may facilitate fall armyworm expansion. Here we conducted three experiments to investigate the potential use of Asteraceae weeds (Emilia sonchifolia var. javanica [E. sonchifolia hereafter] and E. praetermissa) by fall armyworm in Taiwan: (1) The feeding experiment examined fall armyworm performance on the two Emilia species against the control (artificial diet). (2) The host-plant shift experiment tested if fall armyworm can survive on the Emilia species after depleting its primary host (maize). (3) Spatial analysis mapped current fall armyworm invasions, maize production areas, and the distribution of Emilia host plants (if confirmed) to demonstrate the potential of Asteraceae weeds as fall armyworm's untapped resource. The results indicated that fall armyworm could complete its life cycle on E. sonchifolia but not E. praetermissa. Compared to the control, both sexes of fall armyworms on E. sonchifolia performed similarly in survivorship, larval weight, larval and pupal duration, but worse in pupal length and weight. In addition, larvae can switch to E. sonchifolia after depleting maize, reaching adult emergence and producing fertile eggs. The spatial analysis demonstrated hotspots of fall armyworm invasions and a large area of E. sonchifolia as potential food resource for future fall armyworm expansion. Overall, our results raise concerns that overlooking the use of weeds from the Asteraceae family may lead to an underestimation of future fall armyworm expansion. [ABSTRACT FROM AUTHOR]

There is a lack of long-term information on the use of industry forest residues in Pinus taeda L plantations for purposes of enhancing sustainability. The study goal was to evaluate tree growth and nutrition, soil chemical properties, litter accumulation, and weed occurrence in a Pinus taeda L. system amended with alkaline residues from recycled paper. The residues were broadcasted at planting using different rates (0, 10, 20, 30, and 40 t ha−1) on a sandy soil with low fertility. Tree diameter and height along with soil chemical properties were monitored for 15 years. At 15 years samples of litter, weeds, and soil were collected for evaluation. Over 15 years of monitoring, no changes in tree growth or final yield were observed despite increased Ca and reduced Mn foliar tissue concentrations. Low Mg concentration in needles combined with symptoms resembling Mg deficiency and a high increase in Ca levels, suggest that this nutrient could be a limiting factor in tree response. At the same time, a reduction in weed mass with residue application was verified. Residue amendment increased soil Ca and attenuated acidity down to 60 cm after 15 years with the maximum effect on soil properties at ~ 13 years. Litter decreased from 36.2 (control) to 26.9 Mg ha−1 (highest rate) but increased Ca and diminished Al concentrations. The alkaline residue (rich in Ca) improved soil chemical properties at the surface and subsurface, decreased weed growth, increased Ca and reduced Mn in needles, but probably failed to increase tree yield due to an Mg deficiency. [ABSTRACT FROM AUTHOR]

BACKGROUND: A 4‐year experiment evaluated the effects of different integrated weed management (IWM) programs on the evolution of a Echinochloa crus‐galli population resistant to acetolactate synthase (ALS) inhibitors in a maize cropping system. The programs included the continued use of ALS inhibitors, mixing them with alternative herbicides, or without ALS‐inhibitors, in all cases under maize monocrop or a biennial crop rotation. RESULTS: IWM programs that relied solely on non‐ALS‐inhibitors usually achieved high control levels across years (> 90%). Additionally, Trp574Leu‐resistant plants became prevalent (> 90%) in programs only using ALS inhibitors, while in the rest the frequency of susceptible plants did not substantially decrease below 40%. Regarding the other monitored grass weeds, Digitaria sanguinalis and Panicum dichotomiflorum were effectively controlled in programs using ALS‐inhibitors without soybean rotation or in programs without ALS‐inhibitors altogether, excepting the program relying on an 4‐hydroxyphenylpyruvate dioxygenase (HPPD)‐inhibitor under maize monocrop for the latter species (0%). CONCLUSION: At the end of the experiment, the only IWM programs that reduced infestation levels were the one without ALS‐inhibitors under soybean rotation, and the one with standard pre‐emergence treatments. These findings highlight the effectiveness of crop rotation and alternative herbicides both pre‐ or post‐emergence in controlling E. crus‐galli. ALS‐inhibitors, while challenged by resistance in E. crus‐galli, remain valuable tools for managing other grass weed species in maize. It is crucial to adapt IWM strategies for herbicide‐resistant E. crus‐galli and other grass weed populations to mitigate the further evolution of resistance. © 2024 Corteva Agriscience. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Several Amaranthus hybridus L. biotypes present single and triple amino acid substitutions in EPSPS (5‐enolypyruvylshikimate‐3‐phosphate synthase). In resistant and tolerant species to glyphosate, differential susceptibility and alterations in the EPSPS sequence could cause modifications in their morphological–structural characteristics, an issue that is unknown for biotypes of A. hybridus. The aim of the work was to determine the susceptibility to glyphosate, the presence of mutations in EPSPS and the growth form in four biotypes of this weed from north‐central Argentina. To carry out this, a dose–response assay was conducted, to determine the presence of mutations in the EPSPS, DNA was extracted, amplified and sequenced, and finally, to evaluate the morphological–structural variations, the growth form was analysed. Our findings revealed that Ah03, Ah07 and Ah36 biotypes had resistance factors of 22 to 118. The EPSPS sequence remains unaltered in the Ah39 biotype, leading it to be considered a susceptible biotype. Biotypes Ah03 and Ah36 had heterozygous changes in the DNA sequence resulting in amino acid substitutions at positions 102, 103 and 106 being considered resistant biotypes, whereas in Ah07 some individuals showed unaltered DNA sequences and others exhibited heterozygous changes. The growth form was quantitatively different between biotypes, standing the most susceptible biotype that produced more seeds and required less thermal time for the appearance of the terminal inflorescence. The present investigation provides new evidence that resistant biotypes with the triple DNA mutation exhibit variations in the growth form compared to susceptible biotypes of this weed. [ABSTRACT FROM AUTHOR]

AbstractThis study compared the weed suppression ability of a native cover crop species phacelia (Phacelia tanacetifolia), an introduced cover crop species rye (Secale cereale L.), and a no cover crop (herbicide‑managed) system in a vineyard. Cover crops were sown in the interrow spaces of the grapevine rows. Percent weed cover after the cover crop termination was lower in the interrow of the phacelia than the no cover crop plots. During the cover crop growing season, phacelia suppressed weeds more than rye. However, the weed seedbank of the cover crop plots was greater than that of the no cover crop plots. [ABSTRACT FROM AUTHOR]

Saudi Arabia has implemented ambitious environmental protection programs by creating numerous nature reserves throughout the country. Establishment of the latter nature reserves has led to farm abandonment and the initiation of ecosystem recovery processes. Agricultural practices are known to impact the structure and physicochemical properties of soils while also often markedly affecting natural ecosystem restoration processes. Moreover, weed proliferation in crop fields may modify soil seed banks (SSB), thereby impacting subsequent vegetation recovery. Therefore, it is essential to assess SSB compositions in degraded sites, such as abandoned farms (AF), so as to identify weed species and design efficient restoration strategies in hyperarid ecosystems. In this study, SSB compositions in upper and deep soil layers, standing vegetation compositions, and soil chemical properties were analyzed and compared for two natural ecosystems (NE), two abandoned orchards (AO), two AF, and two natural evaporite basins (EB). NE, AO, AF, and EB all exhibited similar chemical properties, suggesting that former agricultural activities have been guided by a fine understanding of the local environments. Agriculture had impacted the species composition of the observed standing vegetation and germinable SSBs, which could be partly explained by soil property modifications. The findings highlighted that SSBs would warrant detailed study prior to designing ecological restoration strategies, and that the drivers of horizontal and vertical weed dissemination in hyperarid ecosystems should also be explored to gain further insight into weed proliferation patterns and to adapt restoration strategies accordingly. [ABSTRACT FROM AUTHOR]

Introduction: Throughout domestication, crop plants have gone through strong genetic bottlenecks, dramatically reducing the genetic diversity in today's available germplasm. This has also reduced the diversity in traits necessary for breeders to develop improved varieties. Many strategies have been developed to improve both genetic and trait diversity in crops, from backcrossing with wild relatives, to chemical/radiation mutagenesis, to genetic engineering. However, even with recent advances in genetic engineering we still face the rate limiting step of identifying which genes and mutations we should target to generate diversity in specific traits. Methods: Here, we apply a comparative evolutionary approach, pairing phylogenetic and expression analyses to identify potential candidate genes for diversifying soybean (Glycine max) canopy cover development via the nuclear auxin signaling gene families, while minimizing pleiotropic effects in other tissues. In soybean, rapid canopy cover development is correlated with yield and also suppresses weeds in organic cultivation. Results and discussion: We identified genes most specifically expressed during early canopy development from the TIR1/AFB auxin receptor, Aux/IAA auxin coreceptor, and ARF auxin response factor gene families in soybean, using principal component analysis. We defined Arabidopsis thaliana and model legume species orthologs for each soybean gene in these families allowing us to speculate potential soybean phenotypes based on well-characterized mutants in these model species. In future work, we aim to connect genetic and functional diversity in these candidate genes with phenotypic diversity in planta allowing for improvements in soybean rapid canopy cover, yield, and weed suppression. Further development of this and similar algorithms for defining and quantifying tissue- and phenotype-specificity in gene expression may allow expansion of diversity in valuable phenotypes in important crops. [ABSTRACT FROM AUTHOR]

In the field of object detection, enhancing algorithm performance in complex scenarios represents a fundamental technological challenge. To address this issue, this paper presents an efficient optimized YOLOv8 model with extended vision (YOLO-EV), which optimizes the performance of the YOLOv8 model through a series of innovative improvement measures and strategies. First, we propose a multi-branch group-enhanced fusion attention (MGEFA) module and integrate it into YOLO-EV, which significantly boosts the model's feature extraction capabilities. Second, we enhance the existing spatial pyramid pooling fast (SPPF) layer by integrating large scale kernel attention (LSKA), improving the model's efficiency in processing spatial information. Additionally, we replace the traditional IOU loss function with the Wise-IOU loss function, thereby enhancing localization accuracy across various target sizes. We also introduce a P6 layer to augment the model's detection capabilities for multi-scale targets. Through network structure optimization, we achieve higher computational efficiency, ensuring that YOLO-EV consumes fewer computational resources than YOLOv8s. In the validation section, preliminary tests on the VOC12 dataset demonstrate YOLO-EV's effectiveness in standard object detection tasks. Moreover, YOLO-EV has been applied to the CottonWeedDet12 and CropWeed datasets, which are characterized by complex scenes, diverse weed morphologies, significant occlusions, and numerous small targets. Experimental results indicate that YOLO-EV exhibits superior detection accuracy in these complex agricultural environments compared to the original YOLOv8s and other state-of-the-art models, effectively identifying and locating various types of weeds, thus demonstrating its significant practical application potential. [ABSTRACT FROM AUTHOR]

A total of 151 genotypes of durum and bread wheat exhibiting symptoms of stunting and bushy growth, leaf yellowing, and drying of clumps were recorded at ICAR-IARI Regional Station, Indore, Madhya Pradesh, India from 2016 to 2018. The disease incidence was recorded more in durum wheat genotypes as compared to bread wheat genotypes. The presence of any virus, bacterial, and fungal pathogens was ruled out by applying cultural growth and electron microscopy. However, association of phytoplasmas presence was confirmed in 142 (out of 151) durum and bread wheat genotypes by employing PCR primer pairs of 16S rRNA, leuS and secA genes. The sequence analysis of all the genes and in silico RFLP analysis of 16S rDNA sequences of wheat phytoplasma strains identified them as rice yellow dwarf group (16SrXI-B) and Bermuda grass white leaf group (16SrXIV-A). Two symptomatic weed species (Parthenium hysterophorus and Cleome gynandra) tested positive for 16SrXI-B phytoplasma subgroup and four weed species (Cynodon dactylon, Digitaria sanguinalis, Euphorbia hirta and Rhynchosia minima) for 16SrXIV-A phytoplasma subgroup growing in and around wheat fields. Six hopper species identified from symptomatic wheat fields were also analyzed for phytoplasma presence. Three hopper species viz., Sogatella furcifera, Balclutha rubrostriata, and Exitianus indicus were tested positive to phytoplasmas in 16SrXIV group, while Sogatella kolophon, Cofana unimaculata, and Maiestas sp. tested positive to 16SrXI group of phytoplasmas in nested PCR assays. Transmission assays revealed that S. furcifera and B. rubrostriata successfully transmitted the 16SrXIV-A strain from infected wheat to healthy wheat plants; however, C. unimaculata was able to transmit 16SrXI-B subgroup from infected wheat to healthy wheat plants under glasshouse conditions. A variation in phytoplasma associated disease incidence was recorded on wheat genotypes in different years and was also found positively correlated with temperature, humidity, and hopper population. The identification of similar phytoplasma strains (16SrXI and 16SrXIV group) from wheat, weeds, and hoppers indicated potential risk of transmission of these strains to wheat genotypes and other agricultural crops, which needs further investigations on epidemiological aspects. [ABSTRACT FROM AUTHOR]

Synergistic effects of herbicidal rice husks and pyrolysis liquid from waste wood-based panels were studied relative to the germination of three common weed species in a tea plantation. The pyrolysis liquid consisted of various organic acids, phenols, alcohols, ketones, and nitrogen compounds, with organic acids accounting for up to 46.8% of the content. Three seeds of smooth crabgrass (Digitaria ischaemum), annual fleabane (Erigeron annuus), and hedge-parsley (Torilis scabra (Thunb.) DC) were treated with 2000 and 4000 L/ha of pyrolysis liquid, as well as 50, 100, and 200 m³/ha of pyrolysis liquid as a cover material. The pre-emergence herbicide tests demonstrated that the combination of rice husks and pyrolysis liquid effectively inhibited seed germination and aboveground biomass of the weeds. The weed control effect increased with the increase in the amount applied. The combination of rice husks (200 m³/ha) and pyrolysis liquid (4000 L/ha) exhibited the highest weed control efficacy, reducing seed germination and aboveground biomass by 69.1%, 79.5%, and 97.6% for smooth crabgrass, annual fleabane, and hedge-parsley, respectively. Discarded furniture materials and rice husks can both be used as sustainable materials for weed control, offering a fresh approach to the efficient utilization of waste materials. [ABSTRACT FROM AUTHOR]

Vegetation communities can drastically influence the hydrodynamic characteristics of the overland flow, change the overland flow resistance mechanism, and regulate soil erosion. To investigate the effect of grass-shrub vegetation and litter combinations on overland flow resistance, simulated rainfall experiments were carried out. The experiments involved a 15° gradient slope, five rainfall intensities (I = 60–120 mm h−1), five grass-shrub coverages (Cgs), and six litter volumes (Cl). The results showed that the mean values of form resistance under Cgs = 15%–75% ranged from 0.195 to 1.775, and the mean values of form resistance under Cl = 5–25 g m−2 ranged from 0.609 to 2.160. The form resistance of grass-shrub slopes with the addition of litter was 1.82–12.47 times higher than that under a single grass-shrub cover. The order of magnitude of the factors influencing the slope form resistance coefficients of the grass-shrub + litter was Cl > Cgs > Cl × Cgs > I. With varying vegetation kinds and coverage rates, I had diverse effects on form resistance. The resistance superposition principle does not hold under combined vegetation cover conditions. The degree of difference (Δ f form ) in form resistance was inversely proportional to I and directly proportional to Cl. Through dimensional and multiple nonlinear regression analyses, a general model for calculating form resistance was established (Adj. R2 = 0.99, NSE = 0.97). Theoretically, the results of this study can be used to evaluate soil and water conservation during vegetation community succession and restoration. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicinal herbs have strict environmental requirements and are highly susceptible to weed damage, while conventional herbicides can adversely affect their quality. Laser weeding has emerged as an effective method for managing weeds in precious medicinal herbs. This technique allows for precise weed removal without chemical residue and protects the surrounding ecosystem. To maximize the effectiveness of this technology, accurate detection and localization of weeds in the medicinal herb fields are crucial. This paper studied seven species of weeds in the field of Dictamnus dasycarpus, a traditional Chinese medicinal herb. We propose a lightweight YOLO-Riny weed-detection algorithm and develop a YOLO-Riny-ByteTrack Multiple Object Tracking method by combining it with the ByteTrack algorithm. This approach enables accurate detection and localization of weeds in medicinal fields. The YOLO-Riny weed-detection algorithm is based on the YOLOv7-tiny network, which utilizes the FasterNet lightweight structure as the backbone, incorporates a lightweight upsampling operator, and adds structure reparameterization to the detection network for precise and rapid weed detection. The YOLO-Riny-ByteTrack Multiple Object Tracking method provides quick and accurate feedback on weed identification and location, reducing redundant weeding and saving on laser weeding costs. The experimental results indicate that (1) YOLO-Riny improves detection accuracy for Digitaria sanguinalis and Acalypha australis, ultimately amounting to 5.4% and 10%, respectively, compared to the original network. It also diminishes the model size by 2 MB and inference time by 10 ms, making it more suitable for resource-constrained edge devices. (2) YOLO-Riny-ByteTrack enhances Multiple Object Tracking accuracy by 3%, reduces ID switching by 14 times, and improves overall tracking accuracy by 3.4%. The proposed weed-detection and localization method for Dictamnus dasycarpus offers fast detection speed, high localization accuracy, and stable tracking, supporting the implementation of laser weeding during the seedling stage of Dictamnus dasycarpus. [ABSTRACT FROM AUTHOR]

This study presents an improved weed detection model, ADL-YOLOv8, designed to enhance detection accuracy for small targets while achieving model lightweighting. It addresses the challenge of attaining both high accuracy and low memory usage in current intelligent weeding equipment. By overcoming this issue, the research not only reduces the hardware costs of automated impurity removal equipment but also enhances software recognition accuracy, contributing to reduced pesticide use and the promotion of sustainable agriculture. The ADL-YOLOv8 model incorporates a lighter AKConv network for better processing of specific features, an ultra-lightweight DySample upsampling module to improve accuracy and efficiency, and the LSKA-Attention mechanism for enhanced detection, particularly of small targets. On the same dataset, ADL-YOLOv8 demonstrated a 2.2% increase in precision, a 2.45% rise in recall, a 3.07% boost in mAP@0.5, and a 1.9% enhancement in mAP@0.95. The model's size was cut by 15.77%, and its computational complexity was reduced by 10.98%. These findings indicate that ADL-YOLOv8 not only exceeds the original YOLOv8n model but also surpasses the newer YOLOv9t and YOLOv10n in overall performance. The improved algorithm model makes the hardware cost required for embedded terminals lower. [ABSTRACT FROM AUTHOR]

Annual ryegrass (Lolium rigidum) is a problematic weed in winter crops and fallows in the southeastern cropping region (SCR) of Australia. This weed has evolved resistance to multiple herbicide groups, globally. In Australia, L. rigidum is more prevalent in the western and southern regions than in SCR. To assess the herbicide resistance status of L. rigidum, the response of five L. rigidum populations (collected from the SCR) to glyphosate, glufosinate, paraquat, haloxyfop-P-ethyl, and clethodim is determined using dose–response curves. Three parametric logistic models are used to determine the herbicide dose required to achieve 50% survival (LD50) and 50% growth reduction (GR50). The LD50 values for 50% survival at 28 days after treatment range from 1702 g a.e. ha−1 to 8225 g a.e. ha−1 for glyphosate, 1637 g a.i. ha−1 to 1828 g a.i. ha−1 for glufosinate, 141 g a.i. ha−1 to 307 g a.i. ha−1 for paraquat, 11 g a.i. ha−1 to 107 g a.i. ha−1 for haloxyfop-P-ethyl, and 17 g a.i. ha−1 to 48 g a.i. ha−1 for clethodim. The resistance factor, based on GR50 value, is highest in the S7 population (2.2 times) for glyphosate, the S11 population (2.3 times) for glufosinate, the S11 population (2.0 time) for paraquat, the S7 population (3.9 times) for haloxyfop-P-ethyl, and the S3 population (3.1 times) for clethodim, compared with the susceptible or less tolerant population. The S11 population is found to be resistant to five tested herbicides, based on resistance factors. Similarly, the S3 population is highly resistant to glyphosate, haloxyfop-P-ethyl, and clethodim compared with the W4 population. These results suggest that L. rigidum populations in the SCR exhibit resistance to multiple herbicide groups at labelled field rates. The findings highlight the necessity of adopting an integrated management approach, including the use of residual herbicides, tank mixing herbicides with different modes of action, and rotating herbicides in conjunction with cultural and mechanical control methods. [ABSTRACT FROM AUTHOR]

Cyperus sesquiflorus is commonly called fragrant kyllinga, fragrant spikesedge, or fragrant flatsedge. It is a cespitose perennial herb with a Pantropical distribution. In Brazil, it is a native species, being commonly named fragrant grass due to its aromatic content. In this study, the essential oil (EO) of C. sesquiflorus was extracted by hydrodistillation with a Clevenger apparatus. Yields of the samples ranged between 0.12% and 0.27% (v/w) oils from fresh and dehydrated whole flowering plants (with roots) and the oil was analyzed by Gas Chromatography/-Mass spectrometry/flame ionization detection (GC-MS/FID) and Gas chromatography/Mass spectroscopy (GC/MS). The main constituent of the oil, neopetasan (3S,4aR,5S)-4a,5-dimethyl-3-(prop-1-en-2-yl)-4,4a,5,6,7,8 hexahydronaphthalen-2(3 H)-one, was isolated by preparative thin layer chromatography (PTLC) and its structure was elucidated by extensive one- and two-dimensional nuclear magnetic resonance (1D/2D-NMR) (COSY, HSQC, HMBC, and NOESY) and Fourier transform infrared (FTIR) spectroscopy in combination with MS and comparison with literature data. [ABSTRACT FROM AUTHOR]

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Sesquiterpene lactones (SLs) are compounds that are highly produced in Cynara cardunculus leaves, known for their phytotoxic activity. This study aims to assess SL-enriched fractions' (cynaropicrin, aguerin B, and grosheimin) phytotoxic potentials and putative modes of action, compared to an initial extract, using two approaches: first, against a panel of nine weed species in pre-emergence, and then on Portulaca oleracea L.'s post-emergency stage. The SL-enriched fractions demonstrated greater phytotoxic activity when compared with the C. cardunculus leaf initial extract. The SL-enriched fractions had higher activity at root growth inhibition over the panel tested, doubling the activity in five of them at 800 ppm. Regarding the post-emergence bioassay, the SL-enriched fractions had a higher influence on the plants' growth inhibition (67% at 800 ppm). The SL-effects on the plants' metabolisms were evidenced. The total chlorophyll content was reduced by 65% at 800 ppm. Oxidative stress induction was observed because of the enhancement in MDA levels at 800 ppm compared to control (52%) and the decrease in SOD-specific activity from 4.20 U/mg protein (400 ppm) to 1.74 U/mg protein (800 ppm). The phytotoxic effects of the SL-enriched fractions suggest that they could be used for a future bioherbicide development. [ABSTRACT FROM AUTHOR]

Objectives: This study was conceived with the aim of translating the experience and knowledge of the research group into the design and creation of multi-active phytocomplex cocktails from lyophilised winery by-products (Grape Pomace—GP) and weeds (Sambucus ebulus L., Dwarf Elder—DE). Methods: Quantification of bioactive molecules was performed by high-performance liquid chromatography (HPLC) method. Results: In the extract obtained from lyophilised GP, the most dominant component that was quantified was petunidin-3-glucoside. Prominent compounds that were quantified in DE extract were cyanidin derivatives. The total number of microorganisms in lyophilisates is low, but some of them still survive lyophilisation. Antibacterial activity was determined by microdilution, the minimum inhibitory concentration (MIC) of the tested bacteria ranged from 0.78 mg/mL to 25.00 mg/mL. Antibacterial susceptibility testing (AST) revealed that Klebsiella spp. and Acinetobacter baumannii complex are extensively drug-resistant (XDR). Conclusions: The GP + DE cocktail showed very strong AB power against both tested XDR bacteria. The total phenolic content and antioxidative effect (determined spectrophotometrically) indicate their linear correlation. [ABSTRACT FROM AUTHOR]

Canopy coverage calculated from 2D images effectively estimates several parameters, such as dry weight above the ground, stem number, and risk of lodging, without destroying the crops. This study aimed to clarify how to accurately calculate canopy coverage, regardless of environmental conditions, using various colour models and a relative depth estimation model, MiDaS. For wheat cultivated in 2022/23, the canopy coverage at the initiation of the stem elongation stage (CC30), calculated using only the HSV colour model, was overestimated because of the presence of weeds. However, when the heatmap generated using MiDaS was combined with the results extracted from the HSV colour model, it showed a CC30 similar to the accurate CC30 calculated by hand drawing, regardless of the wheat variety, sowing pattern, and location of the image taken, with an RMSE as low as 3.48. The CC30 calculated by combining the HSV colour model and MiDaS was significantly positively correlated with the number of stems, dry weight above ground, and nitrogen content above ground at the initiation of the stem elongation stage of 'Sanukinoyume 2009' grown in 2021/22 and 2022/23 (n = 72, r > 0.798). The combination of the HSV colour model and MiDaS effectively and accurately calculates canopy coverage regardless of environmental conditions and can be used for growth diagnosis and variable nitrogen fertiliser application after the initiation of the stem elongation stage. [ABSTRACT FROM AUTHOR]

Crop productivity is affected by various abiotic and biotic factors. Weeds act as the most serious biological constraint by reducing crop yield, harbouring insect pests and causing serious health hazards. Chemical herbicides were widely employed for weed control in agricultural fields. However, an increase in herbicide-resistant weeds and rising environmental concerns arising from the overuse of synthetic herbicides have led scientists to explore natural ways of managing weeds that are cost-effective and environment-friendly. Ecological control by allelopathic crops has proved to be of great significance in weed management. This review focuses on the problem of herbicide resistance in weeds and the role of allelochemicals in biological weed control. Additionally, the review includes the discussion on the allelopathic potential of various crop plants for weed control which can be exploited for the development of cost-effective and environment-friendly bioherbicide. Further, the discussion on retention and biodegrability of the allelochemicals in rhizosphere along with the studies involving genetic mechanisms underlying allelopathy that will direct the future researches for further progress using allelopathy as a potential tool in sustainable agriculture. [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum L.) cultivation in Pakistan faces challenges, with black scurf disease caused by Rhizoctonia solani Kühn being a significant concern. Conventional methods like chemical fungicides partially control it, but an effective solution is lacking. This study explores the potential of biofertilizers and soil amendments from Asteraceae weed biomass to manage the disease. Two potato varieties, Karoda and Sante, were chosen, and two biofertilizers, Fertibio and Feng Shou, were tested alone or with Xanthium strumarium biomass. Disease pressure was highest in the positive control, with significant reduction by chemical fungicide. X. strumarium biomass also decreased disease incidence significantly. Fertibio showed better efficacy than Feng Shou. Physiological and biochemical attributes of plants improved with biofertilizer and biomass application. Tuber weight, photosynthetic pigments, total protein content, and antioxidant enzymes (CAT, POX, and PPO) were positively correlated. Combined application of Fertibio and S. marianum biomass effectively managed black scurf disease. These eco-friendly alternatives could enhance disease management and yield. Future research should explore their cost-effectiveness, commercialization, and safety. [ABSTRACT FROM AUTHOR]

Background:Methods:Results:Conclusions:Ripgut brome (Bromus diandrus Roth) is a problematic weed in New Zealand cereals and has developed resistance to various herbicides worldwide, including ACCase, ALS, and EPSPS inhibitors. A population in New Zealand's South Island from wheat recently showed resistance to the ALS-inhibitor pyroxsulam. This study investigates the resistance level in this population.The resistant ripgut brome population was compared to a susceptible population from a nearby organic farm. The level of resistance to pyroxsulam was determined using dose–response assays. The cytochrome P450 inhibitor malathion was used to evaluate the possible role of cytochrome P450 in herbicide metabolism.The estimated LD50 for pyroxsulam in the resistant population was significantly higher (126 g ai ha−1), suggesting a 20-fold reduction in sensitivity compared to the control (6 g ai ha−1). Malathion pre-treatment increased herbicide sensitivity in susceptible and resistant populations.This study confirms significant resistance to pyroxsulam in a New Zealand ripgut brome population and suggests that a target-site resistance mechanism is the most likely explanation. This research adds to global evidence that ripgut brome can become resistant to pyroxsulam and underscores the escalating issue of herbicide-resistant weeds in New Zealand agriculture. [ABSTRACT FROM AUTHOR]

Corn is the second most cultivated crop in Brazil, the number-one country in pesticide consumption. Chemical control of weeds is performed using herbicides such as S-metolachlor with pre- and post-emergence action and thus the toxicity of herbicides constitutes a matter of great concern. The present investigation aimed to examine the effects of an S-metolachlor-based herbicide on Lactuca sativa L. (lettuce) and Zea mays L. (maize) utilizing various bioassays. The test solutions were prepared from commercial products containing the active ingredient. Seeds from the plant models were exposed in petri dishes and maintained under biochemical oxygen demand (BOD) at 24°C. Distilled water was negative and aluminium positive control. Macroscopic analyses (germination and growth) were conducted for both plant species, and microscopic analysis (cell cycle and chromosomal alterations) were performed for L. sativa root tip cells. Detrimental interference of S-metolachlor-based herbicide was noted with lettuce for all parameters tested reducing plant germination by over 50% and the germination speed by over 45% and showing a significant decrease in mitotic index, from 16.25% to 9,28% even on the lowest concentration tested. In maize, there was no significant interference in plant germination; however, speed of germination was significantly hampered, reaching a 51.22% reduction for the highest concentration tested. Data demonstrated that the herbicide was toxic as evidenced by its phyto- and cytotoxicity in L. sativa L. and Z. mays L. [ABSTRACT FROM AUTHOR]

Logging operations of Liriodendron tulipifera L., as timber trees, and fallen leaves in autumn from ornamental trees produce a large amount of leaf waste. In this study, the allelopathy of L. tulipifera fresh and fallen leaves was investigated for the development of potential applications of leaf waste. The extracts of fresh and fallen leaves of L. tulipifera showed growth inhibitory activity against weed species, Vulpia myuros (L.) C.C.Gmel., Echinochloa crus-galli (L.) P.Beauv., and Lolium multiflorum Lam., under laboratory conditions. The powder of L. tulipifera fresh and fallen leaves also inhibited the germination of E. crus-galli under greenhouse conditions. A potent allelochemical was isolated from fresh and fallen leaf extracts through a bioassay-guided separation process, and was identified as lipiferolide. Lipiferolide inhibited the growth of L. multiflorum and Lepidum sativum in a concentration-dependent manner. This investigation suggests that the leaf waste of L. tulipifera from logging operations and fallen leaves is potentially useful for the purpose of weed control, such as through the use of soil additive materials from leaves or the creation of foliar spray from leaf extracts. The development of weed control materials using L. tulipifera leaf waste may be a means with which to minimize waste, reducing environmental impacts and economic concerns. [ABSTRACT FROM AUTHOR]

A study was carried out to ascertain the impact of planting time and weeding schedule on the yield and quality of baby corn. The trial included three planting times viz. 15 November, 15 December and 14 January and five levels of weeding regime viz. no weeding, two hand weeding (HW) at 15 days after sowing (DAS) and 30 DAS, herbicide pendimethalin @ 2.5 L ha-1 (pre-emergence) + one HW at 30 DAS, herbicide pyrazosulfuran-ethyl @ 2.0 L ha-1 (post-emergence) + one HW at 30 DAS and combined herbicide of pendimethalin + pyrazosulfuran-ethyl. The maximum cob yield with husk (11.93 t ha-1) and cob yield without husk (3.07 t ha-1) were obtained from the 15 December sowing with the application of pendimethalin followed by pyrazosulfuran-ethyl. Plants sown on 15 December with the application pyrazosulfuran-ethyl with one HW at 30 DAS gave the highest protein content in cobs (20.20%), while the leaf protein content showed the highest result (18.70%) in the plants sown on 15 December with no weeding. Therefore, it can be concluded that the baby corn might be planted on December 15 with the combined application of pendimethalin + pyrazosulfuran-ethyl herbicides and pyrazosulfuran-ethyl + one HW at 30 DAS for maximum cob yield and protein content, respectively. [ABSTRACT FROM AUTHOR]

Glyphosate (GLY), the most widely used herbicide, has been regarded as an emergent environmental contaminant due to its constant and cumulative use, with potential harm to non‐target organisms, such as crops, disrupting cells' redox balance. Therefore, plants need to fine‐tune their antioxidant (AOX) mechanisms to thrive under GLY‐contaminated environments. Proline overaccumulation is a common response in plants exposed to GLY, yet its role in GLY‐induced toxicity remains unclear. Thus, this study explores whether Pro overaccumulation in response to GLY is perceived as a downstream tolerance mechanism or an early‐warning stress signal. To investigate this, Arabidopsis thaliana T‐DNA mutant lines for Pro biosynthetic (P5CS1) and catabolic genes (ProDH) were used and screened for their GLY susceptibility. Upon seedlings' exposure to GLY (0.75 mg L−1) for 14 days, the herbicide led to reduced biomass in all genotypes, accompanied by Pro overaccumulation. Mutants with heightened Pro levels (prodh) exhibited the greatest biomass reduction, increased lipid peroxidation (LP), and hydrogen peroxide (H2O2) levels, accompanied by a compromised performance of the AOX system. Conversely, p5cs1–4, mutants with lower Pro levels, demonstrated an enhanced AOX system activation, not only with increased levels of glutathione (GSH) and ascorbate (AsA), but also with increased activity of both ascorbate peroxidase (APX) and catalase (CAT). These findings suggest that Pro overaccumulation under GLY exposure is associated with stress sensitivity rather than tolerance, highlighting its potential as an early‐warning signal for GLY toxicity in non‐target plants and for detecting weed resistance. [ABSTRACT FROM AUTHOR]

Bidens pilosa has been widely distributed from tropical to temperate regions and is often reported as a weed in agriculture. It readily thrives in various environments, naturally spreading to open areas and artificial ecosystems, establishing new populations, emphasising the need for ecological studies to prevent its invasive potential. In this study, we focused on population study of B. pilosa and its distribution in Bandung as urban area. Survey was conducted using 1x1 m quadrate plots in eight locations (24 plots). Individual number of B. pilosa, the number of flowers in each individual, coordinates, and altitude of each plot were recorded to describe population structure and map this population in Bandung. Air temperature (°C), humidity (%), light intensity (Lux), and soil water content (%) were measured. Individual number and environmental condition are analysed using cluster analysis and PCA, then mapped using IDW (Inverse Distance Weighting). The highest population in AR (652 ind), followed by CG (626 ind), TR (253 ind), PA (135 ind), CW (78 ind), NR (39 ind), PU (28 ind), and PR (20 ind). On average, each B. pilosa individual produces 61 inflorescences, indicating a mature population with all developmental stages present across all locations. Ordination plots shows that B. pilosa has wide range of environmental condition from open to shade area with various environmental condition. Open areas, settlements, and agriculture host dense B. pilosa populations, and its biological traits suggest it may become invasive without proper control. [ABSTRACT FROM AUTHOR]

Acetolactate synthase (ALS) inhibitor herbicides are among widely marketed herbicide chemistries that act both against grass and broad-leaved weeds. Sorghum (Sorghum bicolor (L.) Moench) variants carrying resistance to ALS inhibitor herbicides were developed as a post-emergence weed control solution in sorghum. However, some ALS-resistant lines exhibit noticeable interveinal chlorosis at seedling stage, leading to reduced vigor. Although the plants eventually recover at an advanced growth stage, this may be a source of concern for growers and can undermine adoption of the technology. This study was initiated to identify mechanisms related to the manifestation of this phenotype. Two ALS-resistant genotypes, one displaying a yellow phenotype and the other a normal green phenotype, were cultivated, and tissue samples were collected at four time intervals, with the final sampling occurring after the genotypes had fully re-greened. RNA was extracted from the tissue samples and subjected to RNA-Seq analysis. Differential gene expression analysis was carried out using DESeq2, and a selected set of genes were confirmed via qRT-PCR. Gene Ontology enrichment and SorghumCyc pathway analysis uncovered notable regulatory changes in genes associated with chloroplasts, plant defense responses, and hormonal networks in the yellow genotypes. The pattern of gene expression strongly mimicked responses under abiotic stresses. In addition, the findings offer new insights into the potential for sorghum genotypes resistant to environmental stresses to also exhibit tolerance to a range of additional stresses. [ABSTRACT FROM AUTHOR]

Currently, multi-layer deep convolutional networks are mostly used for field weed recognition to extract and identify target features. However, in practical application scenarios, they still face challenges such as insufficient recognition accuracy, a large number of model parameters, and slow detection speed. In response to the above problems, using chickweed as the identification object, a weed identification model based on improved YOLOv5s was proposed. Firstly, the Squeeze-and-Excitation Module (SE) and Convolutional Block Attention Module (CBAM) were added to the model's feature extraction network to improve the model's recognition accuracy; secondly, the Ghost convolution lightweight feature fusion network was introduced to effectively identify the volume, parameter amount, and calculation amount of the model, and make the model lightweight; finally, we replaced the loss function in the original target bounding box with the Efficient Intersection over Union (EloU) loss function to further improve the detection performance of the improved YOLOv5s model. After testing, the accuracy of the improved YOLOv5s model was 96.80%, the recall rate was 94.00%, the average precision was 93.20%, and the frame rate was 14.01 fps, which were improved by 6.6%, 4.4%, 1.0%, and 6.1%, respectively, compared to the original YOLOv5s model. The model volume was 9.6 MB, the calculation amount was 13.6 GB, and the parameter amount was 5.9 MB, which decreased by 29.4%, 14.5%, and 13.2% compared with the original YOLOv5s model, respectively. This model can effectively distinguish chickweed between crops. This research can provide theoretical and technical support for efficient identification of weeds in complex field environments. [ABSTRACT FROM AUTHOR]

Laser technology can be used to control weeds by irradiating the apical meristematic tissue (AMT) of weeds when they are still seedlings. Two factors are necessary for the successful large-scale implementation of this technique: the ability to accurately identify the apical meristematic tissue and the effectiveness of the localization algorithm used in the process. Based on this, this study proposes a lightweight weed AMT localization algorithm based on YOLO (look only once) instance segmentation. The YOLOv8n-seg network undergoes a lightweight design enhancement by integrating the FasterNet lightweight network as its backbone, resulting in the F-YOLOv8n-seg model. This modification effectively reduces the number of parameters and computational demands during the convolution process, thereby achieving a more efficient model. Subsequently, F-YOLOv8n-seg is combined with the connected domain analysis algorithm (CDA), yielding the F-YOLOv8n-seg-CDA model. This integration enables the precise localization of the AMT of weeds by calculating the center-of-mass coordinates of the connected domains. The experimental results indicate that the optimized model significantly outperforms the original model; the optimized model reduces floating-point computations by 26.7% and the model size by 38.2%. In particular, the floating-point calculation is decreased to 8.9 GFLOPs, and the model size is lowered to 4.2 MB. Comparing this improved model against YOLOv5s-seg and YOLOv10n-seg, it is lighter. Furthermore, it exhibits exceptional segmentation accuracy, with a 97.2% accuracy rate. Experimental tests conducted on five different weed species demonstrated that F-YOLOv8n-seg-CDA exhibits strong generalization capabilities. The combined accuracy of the algorithm for detecting these weeds was 81%. Notably, dicotyledonous weeds were detected with up to 94%. Additionally, the algorithm achieved an average inference speed of 82.9 frames per second. These results indicate that the algorithm is suitable for the real-time detection of apical meristematic tissues across multiple weed species. Furthermore, the experimental results demonstrated the impact of distinctive variations in weed morphology on identifying the location of the AMT of weeds. It was discovered that dicotyledonous and monocotyledonous weeds differed significantly in terms of the detection effect, with dicotyledonous weeds having significantly higher detection accuracy than monocotyledonous weeds. This discovery can offer novel insights and avenues for future investigation into the identification and location of the AMT of weeds. [ABSTRACT FROM AUTHOR]

The steady increase in temperature due to global warming can significantly impact weed growth. This study investigates the response of the yellow foxtail (Setaria pumila (Poir.) Roem. & Schult.) grass weed and the Palmer amaranth (Amaranthus palmeri S. Watson) broadleaf weed to increasing temperature conditions, simulating future climate conditions. Temperature treatments included growing these weeds in three temperature-controlled growth chambers: control or ambient conditions (15.5/12.8 °C day/night), moderately elevated temperatures (17.2/14.4 °C), and elevated temperatures (18.8/16.1 °C). Monthly adjustments in the growth chambers simulated the natural temperature rise observed from April to June in the Southern USA, aligning with the respective treatments. Different plant parameters recorded included days to emergence, number of tillers/leaves, chlorophyll content, days to first inflorescence, biomass, and seed set. One-way ANOVA indicated a significant temperature impact on all the parameters assessed (p < 0.05), except for biomass (for both weeds) and days to first inflorescence and yield (for Palmer amaranth (p > 0.05)). The average days to emergence were the lowest under elevated temperatures (8 days for yellow foxtail and 11 days for Palmer amaranth) when compared to that for the control (10 days for yellow foxtail and 19 days for Palmer amaranth). By week 5, yellow foxtail exhibited notably greater tiller numbers under elevated temperatures compared to that of the control; a similar trend was noticed regarding the number of Palmer amaranth leaves. The average chlorophyll content was the highest under elevated temperature conditions up to week 6 and began decreasing after that for both weeds. The average yield of yellow foxtail under elevated, moderately elevated, and control temperatures was 7.55, 2.69, and 0.88 g, respectively. Even though not significant, the yield of Palmer amaranth was higher under elevated temperature conditions as compared to that under the ambient condition. The biomass of both yellow foxtail and Palmer amaranth were not significantly impacted by temperature (p > 0.05). Our research shows that as temperatures rise, weeds exhibit more vigorous growth and show higher photosynthetic efficiency, which has important implications for how we manage weeds in agriculture. These findings suggest that under warmer conditions, weeds could display more vigorous vegetative growth, thus significantly impacting crop yields. As we face ongoing global warming, it is crucial to consider how temperatures influences weed growth when designing strategies to manage weeds effectively. [ABSTRACT FROM AUTHOR]

In this study, 13 different edible weed species [Centaurea depressa Bieb., Cichorium intybus L., Lactuca serriola L., Malva neglecta Wallr., Papaver dubium L., Polygonum cognatum Meissn., Rumex patientia L., Scorzonera cana (C.A.Mey.Hoffm.), Silene alba (Mill.) Krause, Stellaria media L., Sonchus oleraceus L., Taraxacum officinale, Tragopogon longirostris Bisch] were collected from the same location in the Mediterranean region. Then, the leaves of all species were analyzed by the SPME-GC/MS method for the detection of volatile compounds. The compounds were grouped according to their structures as alcohols, aldehydes, alkanes, ester, furans, hydrocarbons, ketones, sulfur compounds, and terpenes. The percentages of the terpenes, aldehydes and alcoholic compounds were found to have the highest ratios of volatile compounds, respectively. The species found with the highest total terpene percentage was Sonchus oleraceus L. (78.84%), while the lowest one was Stellaria media L. (51.03%). Similarly, the highest total aldehydes percentage was found in Stellaria media L. (38.41%), and the lowest was in Centaurea depressa Bieb. (4.62%). Lastly, the highest total alcohol percentage was observed in Centaurea depressa Bieb. (9.92%) and the lowest was in Malva neglecta Wallr. (1.11%). The limonene, which is an important monoterpene, among 63 components, was found to be the major component in all species with a range of approximately 51-79%. Among them, Sonchus oleraceus L. had the highest limonene content (78.84%). [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the phytotoxic, genotoxic, cytotoxic and antimicrobial effects of the Mentha arvensis L. essential oil (EO). The biological activity of M. arvensis EO depended on the analyzed variable and the tested oil concentration. Higher concentrations of EO (20 and 30 µg mL−1) showed a moderate inhibitory effect on the germination and growth of seedlings of tested weed species (Bellis perennis, Cyanus segetum, Daucus carota, Leucanthemum vulgare, Matricaria chamomilla, Nepeta cataria, Taraxacum officinale, Trifolium repens and Verbena × hybrida). The results obtained also indicate that the EO of M. arvensis has some genotoxic, cytotoxic and proliferative potential in both plant and human in vitro systems. Similar results were obtained for antimicrobial activity against eight bacteria, including multidrug-resistant (MDR) strains [Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Escherichia coli, extended-spectrum beta-lactamase-producing (ESBL) E. coli, Pseudomonas aeruginosa and Salmonella enterica subsp. enterica serovar Enteritidis], with the effect on multidrug-resistant bacterial strains. Research indicates that the EO of M. arvensis shows phytotoxic, genotoxic, cytotoxic and antimicrobial effects, as well as its potential application as a herbicide and against various human diseases. [ABSTRACT FROM AUTHOR]

This article reports on the identification of phytoplasmas associated with Papaya Bunchy Top in Colima, Mexico. Samples were collected from symptomatic and asymptomatic plants, as well as from weeds and insects associated with the crop in four producing municipalities of the state. Through PCR techniques, sequencing, and phylogenetic analysis, phytoplasmas from groups 16SrI, 16SrX, and 16SrXIII were identified in the analyzed papaya plants, weeds, and insects. These results represent the first records of 16SrX and 16SrXIII phytoplasmas in papaya worldwide and in Mexico, respectively. Additionally, it is suggested that weeds and insects could act as natural reservoirs and potential vectors of these bacteria. [Extracted from the article]

Pre‐emergent herbicides can reduce the abundance of invasive annual plants, but they can also harm native plants, particularly annuals or perennial seedlings, including seeds planted during restoration. We assessed the effects of imazapic and indaziflam on invasive target and nontarget native plants in the Great Basin, a region with extensive invasive annual grasses. We tested nontarget effects on native annual forbs in an agricultural field previously used to grow native annual forbs, which contained a large seed bank. We seeded perennial grass (Elymus elymoides) at multiple depths to determine susceptibility and resistance. Herbicides were applied at full and reduced rates to mimic the effect of litter in natural systems. We observed reductions in most non‐native species in all treatments, but also extensive reductions of native annual forbs, although these were offset at lower application rates, and some species (e.g. Amsinckia tessellata and Microsteris gracilis) were less susceptible than others. Herbicides, particularly indaziflam, reduced E. elymoides emergence, but planting seeds at 2–3 cm depths improved emergence, particularly for imazapic, with 15–68% greater emergence than seeds planted at 1 cm. We suggest surveys for native annual forbs and resistant invaders before applying herbicides and field testing to determine whether reduced rates could provide weed control while maintaining annual forbs. We suggest planting E. elymoides at 2–3 cm when applying herbicides, an approach that may be effective for other species. Herbicide use can be an effective tool, but our results indicate that mitigation of nontarget effects will be needed to maintain native plant diversity. [ABSTRACT FROM AUTHOR]

Pyroxasulfone is a very long chain fatty acid (VLCFA) inhibitor (group 15) with potential for preemergence weed control in orchard crops and would be beneficial for reducing selection pressure for resistance to more commonly used herbicides, such as glyphosate. Pyroxasulfone is registered and widely used in corn and soybeans in the United States as a solo product and in several premix formulations. However, there is limited published information on the performance and safety of pyroxasulfone in tree nut orchard systems. To assess the potential fit for pyroxasulfone in this crop sector, a series of crop safety and weed control efficacy experiments were carried out in key California orchard crops and in fallow fields with common orchard weeds. The non-crop studies were conducted near Davis, CA, to evaluate winter annual weed control with pyroxasulfone in comparison with pendimethalin and indaziflam. In addition, an irrigation incorporation experiment was conducted in summer to evaluate the effects of incorporation timing on pyroxasulfone, pendimethalin, and indaziflam efficacy as a measure of relative stability. Orchard weed control experiments were conducted in spring in an almond orchard near Arbuckle, CA, and a walnut orchard near Davis, CA. The orchard experiments included pyroxasulfone, pendimethalin, and indaziflam in various rate combinations with glufosinate. To evaluate crop safety, 2-year experiments were conducted to evaluate repeated applications of above-label rates of pyroxasulfone at 1199 g⋅ha-1 and S-metolachlor at 14,010 g⋅ha-1 on 1- to 2-year-old almond, pistachio, and walnut trees near Davis. Pyroxasulfone performed similarly to commercial standards with up to 95% control of broadleaf and grass weeds with pyroxasulfone and indaziflam providing 96% to 100% control of annual bluegrass, and pyroxasulfone (293 g⋅ha-1) being the only herbicide to suppress (>70%) common lambsquarters at 60 days after treatment (DAT). Other weeds controlled by pyroxasulfone include swinecress, redroot pigweed, yellow nutsedge, and Italian ryegrass. No differences were found among treatments in the incorporation timing study indicating adequate stability on the soil surface under summer conditions. Crop injury was not observed in the established orchards or the young orchard studies and there were no treatment effects on tree trunk diameter of almond, pistachio, and walnut in the 2-year crop safety experiments. These results indicate a potential for pyroxasulfone in California tree nut orchard systems that would be an additional site of action and beneficial for management of herbicide-resistant weeds in these crops. [ABSTRACT FROM AUTHOR]

This study was conducted in a newly established (2-year-old) almond orchard to investigate the effects of five different mulching materials (woven and nonwoven fabric, black and white polyethylene, almond shell) and flame treatments applied at two different frequencies (FL20 and FL30) on weed control and almond growth compared with those of conventional herbicide (glyphosate) application and weedy control. Thus, this study included nine different treatments. The impacts of these treatments on weed density and coverage were periodically monitored. Additionally, the biomass of the weeds was measured at the end of the season to evaluate the effects of the treatments. Because the almond orchard was not yet in the economic fruit-bearing stage, the effects of the treatments were examined in terms of parameters that characterize almond growth, such as plant height, trunk diameter, shoot length, and shoot thickness. The chlorophyll content and water potential values of the trees were also determined. The results of this two-season study indicated that synthetic mulches provided the best outcomes in terms of weed control and almond growth. No weed emergence was observed throughout the season in any of the synthetic mulch treatments. Although almond shells used as organic mulch were highly effective for blocking sunlight, they failed to prevent the growth of some vigorously growing perennials such as Cynodon dactylon and Sorghum halepense that emerged from gaps. Flame treatments demonstrated rapid and effective results; however, they were less successful against the aforementioned monocot perennial weeds and required frequent repetition because of the lack of residual effects. Glyphosate, an herbicide that is commonly used in conventional orcharding, was applied five times throughout the experiment and proved effective weed management compared with that of the weedy control. However, considering the increasing herbicide resistance, environmental and health issues, and growing interest in organic almond cultivation, synthetic mulch applications have emerged as good options. Despite the initially higher establishment costs, synthetic mulches effectively controlled weeds and reduced water stress, thereby promoting almond tree growth. [ABSTRACT FROM AUTHOR]

The present study examines the archaeobotanical remains at Dobbin 27, a settlement site in northern Germany from the Late Bronze Age. Various plant species were identified, including millet, barley, emmer, and various weeds. The overall density of findings was low, with the highest density found in a fire pit outside the house and an adjacent pit. Remains of wild plants such as hazelnuts, acorns, raspberries, and hawthorn were also found, which may have been collected as food. The results of this study contribute to a better understanding of agricultural production and plant-related activities in the Bronze Age. [Extracted from the article]