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Background: The resistance of weeds to herbicides is a significant issue in ensuring future food supply. Specific examples are Plantago lanceolata, Portulaca oleracea and Lolium rigidum, which mainly infect rice, wheat, barley and pastures, and cause high yield losses every year. In this regard, natural products and their mimics have provided new hope as a result of their different modes‐of‐action, activity at low concentrations and reduced pollution effects relative to conventional herbicides. However, the poor water solubility and physicochemical properties of these compounds limit their broad application. These problems can be addressed by formulation techniques, and encapsulation appears to be of great interest. Results: Disulfide herbicides inspired by aminophenoxazinones have been formulated with 2‐hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD), γ‐CD and polymeric nanoparticles (NPs). In silico studies were employed to identify which complexes would be generated and complex formation was confirmed by nuclear magnetic resonance spectroscopy. Solubility diagrams were generated to assess any improvement in water solubility, which was enhanced 2–13‐fold. Scanning electron microscopy and energy‐dispersive X‐ray spectra confirmed the success of the formulation process for the nanoparticles. Formulated compounds were evaluated in an in vitro wheat coleoptile bioassay, with almost 100% elongation inhibition achieved using only water for the bioassay. Specific in vitro testing on weed phytotoxicity showed that the application of core/shell NPs is highly effective in the fight against P. lanceolata seed germination. Conclusions: The formulation of disulfide herbicides with CD complexes and NPs led to an enhancement in water solubility and bioactivity. These systems can be applied in pre‐emergent mode against P. lanceolata, using only water to prepare the sample, and they showed better activity than the positive controls. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

White grubs cause serious yield losses in high-value crops, mainly sugarcane, groundnut, maize and potato, and biological control through entomopathogenic fungi and nematodes is by far the most sustainable management strategy available. In our investigations on the factors causing mortality of white grub larvae (Coleoptera: Scarabaeidae) during rearing, we found an undermined species of the soil-dwelling mite Schizoglyphus sp. associated with the grubs. This is the first report of the occurrence of this mite from India and of its association with scarab larvae. The potential of this mite as a biocontrol agent has to be explored. [ABSTRACT FROM AUTHOR]

This article, published in the journal Microorganisms, focuses on the topic of biological control of plant pathogens. It highlights the importance of addressing crop losses and food security issues caused by factors such as urbanization, climate change, and emerging pests and pathogens. The article discusses the use of microbial biocontrol agents (BCAs) as an environmentally friendly alternative to chemical pesticides. It presents various research contributions in the field, including management strategies for soilborne pathogens, the biocontrol potential of novel compounds and defense inducers, the exploration of biocontrol potential in microbial isolates and genetically engineered strains, and formulation technology. The article concludes by emphasizing the need for more powerful and reliable BCAs to contribute to sustainable agriculture. [Extracted from the article]

Our research delved into unraveling the dynamics governing the distribution and progression of spring barley rust. Over the course of our study, we witnessed the disease's dissemination fluctuate between 21.75% and 30.0%, accompanied by varying intensities ranging from 13.25% to 19.0%. Furthermore, we meticulously observed how the disease impacted the structural aspects of spring barley yield, revealing a strong correlation with coefficients of r=0.973, r=0.980, and r=0.973. In addition to this, we developed predictive models to estimate potential crop yield losses attributed to rust, thereby allowing us to foresee potential reductions in spring barley harvests caused by this disease. [ABSTRACT FROM AUTHOR]

The common hamster in Hungary, once categorized as Least Concern, is now Critically Endangered due to habitat loss from agricultural practices. Despite a peak in population size in 2020, the hamster population in Hungary has reached an all-time low. Conservation efforts are hindered by conflicting laws that allow farmers to exterminate populations without permission, potentially jeopardizing the species. Research shows a decline in genetic diversity and highlights the need for collaboration between conservationists and farmers to protect the Pannonian hamster's future. [Extracted from the article]

In Morogoro Region of south-central Tanzania, loss of crops and safety concerns due to elephants compromises livelihoods in many rural communities relying on subsistence agriculture. Using a social-ecological system framework to examine conflict-coexistence between people and elephants, this paper explores drivers that influence human-elephant interaction and subsistence farmer attitudes towards elephants in 10 villages from three different districts. Surveys and interviews document experiences interacting with elephants along with direct and indirect costs incurred in sharing the landscape, revealing different tolerance levels by residents of subject communities towards elephants that have important implications for elephant conservation. Rather than uniformly negative beliefs about elephants, analyses reveal that over the past decade a shift has occurred from largely favorable to unfavorable. The variables influencing attitudes included amounts of crops lost to elephants, perceived benefits from elephants, amounts of crops lost to other causes, perceived trend of human-elephant conflict (HEC) in the past three decades and level of education. Villager tolerance varied by level of income, perception on how the community coexists with elephants, amounts of crops lost to elephants and compensation. The study contributes to understanding how HEC is affecting the relationship between people and elephants, revealing a shift in the conflict-coexistence continuum from positive to broadly negative and identifying characteristics underlying varying tolerance towards elephants in different communities. Rather than a static condition, HEC emerges under specific conditions at particular times and places through varying, uneven interactions between rural villagers and elephants. In communities vulnerable to food insecurity, such conflict exacerbates existing problems of poverty, social inequality, and feelings of oppression. Addressing the causes of HEC, when possible, will be essential to elephant conservation as well as to improving the wellbeing of rural villagers. [ABSTRACT FROM AUTHOR]

In August 2022, one of the most severe floods in the history of Pakistan was triggered due to the exceptionally high monsoon rainfall. It has affected ~ 33 million people across the country. The agricultural losses in the most productive Indus plains aggravated the risk of food insecurity in the country. As part of the loss and damage (L&D) assessment methodologies, we developed an approach for evaluating crop-specific post-disaster production losses based on multi-sensor satellite data. An integrated assessment was performed using various indicators derived from pre- and post-flood images of Sentinel-1 (flood extent mapping), Sentinel-2 (crop cover), and GPM (rainfall intensity measurements) to evaluate crop-specific losses. The results showed that 2.5 million ha (18% of Sindh's total area) was inundated out of which 1.1 million ha was cropland. The remainder of crop damage came from the extreme rainfall downpour, flash floods and management deficiencies. Thus approximately 57% (2.8 million ha) of the cropland was affected out of the 4.9 million ha of agricultural area in Sindh. The analysis indicated expected production losses of 88% (3.1 million bales), 80% (1.8 million tons), and 61% (10.5 million tons) for cotton, rice, and sugarcane. This assessment provided useful tools to evaluate the L&D of agricultural production and to develop evidence-based policies enabling post-flood recovery, rehabilitation of people and restoration of livelihood. [ABSTRACT FROM AUTHOR]

Farmers in the south-west coastal Bangladesh are frequently affected by climate change due to their proximity to the Bay of Bengal and heavy reliance on agriculture for their livelihoods. In this case, farmers need to know the best implementation methods (adaptation strategies) to reduce crop losses in a changing climate. The present research evaluated the perceptions of farmers to climate change and determine the socio-economic factors which influence the farmers in choosing the right adaptation decisions. Data were collected through close-ended and open-ended structured questionnaire from 52 coastal households and analyzed through descriptive statistics and logistic regression using SPSS V.16. Results revealed that almost all farmers perceived increasing temperature and changes in rainfall patterns over the last 15 years. In response to a changing climate, farmers adopted 13 adaptation strategies where irrigation ranked the first and crop insurance was the last. The logit analysis suggests that household age, education, family income, family member, farm size, farming experience, organizational participations, and training received have a significant influence on farmer's adaptation choices. Despite various support and technological interventions being available, changing weather, natural disaster pattern, lower income, and lack of credit facilities ranked as the highest problems farmers encountered during adaptation. This study helps to identify important household characteristics that can be applied in the future to formulate and implement a successful adaptation policy. Finally, this study recommends that effective training and early warning systems and provision of credit and market access facilities are necessary to enhance farmer's resilience to climate change. [ABSTRACT FROM AUTHOR]

Although aphids are pests and can cause 100% crop loss, they also are food for natural enemies and birds. The objective of this work was to determine predators and parasitoids of aphids and agroecological characteristics of weeds. The study was done in monocultures of intensive agriculture at El Copal Irapuato. Twenty-two plant species were collected, predominantly Asteraceae with eight species; nine species of aphids were collected. Aphis craccivora Koch was on four plant species. Aphidius colemani Viereck parasitized as many as 84% of Uroleucon ambrosiae (Thomas). Allograpta oblicua (Say), Pseudodorus clavatus (F.), and Paragus tibialis (Fallén) hoverflies were found in larvae preying on aphids. The larva of Micromus posticus (Walker) fed on aphids, the first record of immatures of the species of Hemerobiidae in the State of Guanajuato. Other species of predators were reported. [ABSTRACT FROM AUTHOR]

Context: Sulfur deficiency is a limiting factor of cereal crops, causing significant crop losses associated with a decrease in the number of grains. In barley (Hordeum vulgare L.) crops, grain number (and grain yield) is associated with spike biomass at anthesis, which is related to crop growth rate during the period preceding anthesis (i.e. the 'critical period') when spike growth occurs. These relationships have been established for various cultivars under varying radiation intensity and in different locations, and have been confirmed in crops grown under nitrogen and phosphorus deficiencies. Aims: The objective of this study was to determine, for malting barley, whether the effects of sulfur, nitrogen and their interaction on the number of grains per unit area could be explained by changes in crop growth rate or photothermal quotient (ratio of intercepted photosynthetically active radiation to temperature) during the critical period. Methods: Three field experiments were conducted in the Pampean region of Argentina to evaluate the effects of sulfur fertilisation under three levels of nitrogen availability on the number of grains per unit area. Key results: Changes in grain number were associated with crop growth rate or photothermal quotient during the critical period. This association was maintained when sulfur fertilisation changed grain number. Crop growth rate during the critical period varied mainly as a result of changes in accumulated intercepted radiation. Conclusions: Sulfur fertilisation increases grain number and grain yield by increasing radiation interception during the critical period, probably as a consequence of increased leaf area. Implications: The determination of grain number under sulfur deficiency is similar to that observed under deficiencies of other nutrients. Deficiencies of nutrients such as sulfur cause significant crop losses associated with a decrease in the number of grains. In this work, we show that reductions in grain number in barley crops caused by sulfur deficiencies are determined by reductions in crop growth in the period prior to heading known as the 'critical period'. This shows that the effects of deficiencies of different nutrients on cereal yields have some common mechanisms. [ABSTRACT FROM AUTHOR]

Moisture stress during crop growth has been identified as a major impediment to long-term agricultural productivity. Crop losses vary depending on the severity and duration of the drought, as well as the stage of growth. The objective of the present investigation was to identify superior genotypes of horse gram with moisture stress tolerance having high yield and quality, especially suitable for the south-central laterite region of Kerala (India) as well as determine the nature and extent of diversity amongst the genotypes under investigation. In this study, we investigated the response of thirty genotypes of horse gram to their moisture stress tolerance at the seedling stage using PEG 6000 osmoticum in the laboratory and by withholding irrigation at the reproductive stage in the field. The genotypes were evaluated for six different morpho-physiological traits as well as various biometrical, physiological, biochemical and seed quality characters. Results of the analysis of variance revealed that the genotypes varied significantly for all traits. To know the magnitude of genetic diversity existing in genotypes, the Mahanalobis D2 statistic was also performed. The results from both experiments indicated that the genotypes IC22785 and IC139464 have the potential to be used in breeding programs for drought tolerance, as these genotypes recorded superior performance under high moisture stress conditions. The promising genotypes belonged to cluster III in the divergence analysis. Superior segregants may be obtained by crossing clusters I and III, as the highest inter-cluster distance was between them. [ABSTRACT FROM AUTHOR]

Pests are always the main source of field damage and severe crop output losses in agriculture. Currently, manually classifying and counting pests is time consuming, and enumeration of population accuracy might be affected by a variety of subjective measures. Additionally, due to pests' various scales and behaviors, the current pest localization algorithms based on CNN are unsuitable for effective pest management in agriculture. To overcome the existing challenges, in this study, a method is developed for the localization and classification of pests. For localization purposes, the YOLOv5 is trained using the optimal learning hyperparameters which more accurately localize the pest region in plant images with 0.93 F1 scores. After localization, pest images are classified into Paddy with pest/Paddy without pest using the proposed quantum machine learning model, which consists of fifteen layers with two-qubit nodes. The proposed network is trained from scratch with optimal parameters that provide 99.9% classification accuracy. The achieved results are compared to the existing recent methods, which are performed on the same datasets to prove the novelty of the developed model. [ABSTRACT FROM AUTHOR]

Plant growth-promoting rhizobacteria (PGPR) such as the root colonizers Bacillus spp. may be ideal alternatives to chemical crop treatments. This work sought to extend the application of the broadly active PGPR UD1022 to Medicago sativa (alfalfa). Alfalfa is susceptible to many phytopathogens resulting in losses of crop yield and nutrient value. UD1022 was cocultured with four alfalfa pathogen strains to test antagonism. We found UD1022 to be directly antagonistic toward Collectotrichum trifolii, Ascochyta medicaginicola (formerly Phoma medicaginis), and Phytophthora medicaginis, and not toward Fusarium oxysporum f. sp. medicaginis. Using mutant UD1022 strains lacking genes in the nonribosomal peptide (NRP) and biofilm pathways, we tested antagonism against A. medicaginicola StC 306-5 and P. medicaginis A2A1. The NRP surfactin may have a role in the antagonism toward the ascomycete StC 306-5. Antagonism toward A2A1 may be influenced by B. subtilis biofilm pathway components. The B. subtilis central regulator of both surfactin and biofilm pathways Spo0A was required for the antagonism of both phytopathogens. The results of this study indicate that the PGPR UD1022 would be a good candidate for further investigations into its antagonistic activities against C. trifolii, A. medicaginicola, and P. medicaginis in plant and field studies. [ABSTRACT FROM AUTHOR]

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This article was motivated by the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) announcement that on 17 December 2021 it rescinded Federal Orders of 2 May 2007 that regulated (what was believed to be) a new outbreak of the light brown apple moth (LBAM, Epiphyas postvittana (Walker)) in the mainland United States. Our article follows from, and builds on, a 2013 article published by Carey and Harder that outlined major concerns about the LBAM eradication program including the need, cost, safety, practicality, and feasibility of the program and the public opposition to it. The program began with an emergency order based on USDA claims of billions of dollars in potential crop losses and the need to circumvent safety review processes to urgently prevent the pest's establishment. The program ended with the realization by government decision‐makers, 14 years after initiating the program, that LBAM posed no quarantine‐level threat in the first place and with no evidence of any economic damage done by the insect. This article summarizes the mistakes made in devising and carrying out what has ultimately proven to be one of the most oversold, overhyped, misguided, ill‐advised, unnecessary, and costly programs in the recent history of insect eradication programs in California. Termination of the LBAM program by USDA‐APHIS presents an opportunity to review the program to identify lessons learned and provide recommendations to help avoid similar mistakes in future invasive species response programs. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In a controlled environment experiment, we studied how physiological changes in leaves during the vegetative phase regulate final grain yield of wheat crops in salt-affected soils. We also hypothesized that amendments such as biochar (SB) and selenium-chitosan nanoparticles (Se-NPs) can protect wheat plants from salt injury. 20-day-old wheat plants were submitted to 4-week salt stress (3000 ppm NaCl). Soybean straw biochar was mixed with soil media at planting and Se-NPs (30 ppm) was sprayed 5 days after the first salt stress treatment. At the end of 4-week Se-NPs treatment, one set of plants was harvested for studying leaf level physiological changes. The salt-stressed plants accumulated significantly high leaf Na+ (~ 13-fold increase), which trigged oxidative and osmotic damage. This salt-induced cellular injury was evident from significantly high levels of lipid membrane peroxidation and inhibited photosynthesis. Our study suggested that leaf physiological impairment in wheat plants was translated into poor biomass production and grain yield loss at crop maturity. Compared with control, salt-stressed plants produced 43% lesser biomass during vegetative phase, and 62% lesser grain yield at maturity. Amendments such as SB and Se-NPs protected the plants from salt-induced cellular injury by restricting Na+ transport toward leaf tissues. Plants treated with NaCl + SB + Se-NPs accumulated 50% less Na+ concentrations in leaves compared with NaCl-treated plants. Our study also suggested that SB and Se-NPs can restore ionic homeostasis and carbon assimilation in salt-stressed wheat by upregulating key transporter genes in leaves. [ABSTRACT FROM AUTHOR]

Modeling of land use and land cover (LULC) is a very important tool, particularly in the agricultural field: it allows us to know the potential changes in land area in the future and to consider developments in order to prevent probable risks. The idea is to give a representation of probable future situations based on certain assumptions. The objective of this study is to make future predictions in land use and land cover in the watershed "9 April 1947", and in the years 2028, 2038 and 2050. Then, the maps obtained with the climate predictions will be integrated into an agro-hydrological model to know the water yield, the sediment yield and the water balance of the studied area by 2050.The future land use and land cover (LULC) scenarios were created using a CA-Markov forecasting model. The results of the simulation of the LULC changes were considered satisfactory, as shown by the values obtained from the kappa indices for agreement (κstandard) = 0.73, kappa for lack of information (κno) = 0.76, and kappa for location at grid cell level (κlocation) = 0.80. Future scenarios modeled in LULC indicate a decrease in agricultural areas and wetlands, both of which can be seen as a warning of crop loss. There is, on the other hand, an increase in forest areas that could be an advantage for the biodiversity of the fauna and flora in the "9 April 1947" watershed. [ABSTRACT FROM AUTHOR]

Global climate change will probably exacerbate crop losses from insect pests, reducing agricultural production, and threatening food security. To predict where crop losses will occur, scientists have mainly used correlative models of species' distributions, but such models are unreliable when extrapolated to future environments. To minimize extrapolation, we developed mechanistic and hybrid models that explicitly capture range‐limiting processes, and we explored how incorporating mechanisms altered the projected impacts of climate change for an agricultural pest, the South American locust (Schistocerca cancellata). Because locusts are generalist herbivores surrounded by food, their population growth may be limited by thermal effects on digestion more than food availability. To incorporate this mechanism into a distribution model, we measured the thermal effects on the consumption and defecation of field‐captured locusts and used these data to model energy gain in current and future climates. We then created hybrid models by using outputs of the mechanistic model as predictor variables in correlative models, estimating the potential distribution of gregarious outbreaking locusts based on multiple predictor sets, modeling algorithms, and climate scenarios. Based on the mechanistic model, locusts can assimilate relatively high amounts of energy throughout temperate and tropical South America; however, correlative and hybrid modeling revealed that most tropical areas are unsuitable for locusts. When estimating current distributions, the top‐ranked model was always the one fit with mechanistic predictors (i.e., the hybrid model). When projected to future climates, top‐ranked hybrid models projected range expansions that were 23%–30% points smaller than those projected by correlative models. Therefore, a combination of the correlative and mechanistic approaches bracketed the potential outcomes of climate change and enhanced confidence where model projections agreed. Because all models projected a poleward range expansion under climate change, agriculturists should consider enhanced monitoring and the management of locusts near the southern margin of the range. [ABSTRACT FROM AUTHOR]

La Montaña, one of seven regions making up the state of Guerrero, Mexico, has high social-ecological vulnerability. Its extreme poverty and marginalization levels are among the country's highest, superimposed in a context of severe ecosystem degradation. We evaluated the social-ecological resilience of two indigenous communities of this region engaged in agroecological projects by integrating the Resilience Assessment and MESMIS methodological proposals, using qualitative and quantitative indicators. The most critical aspects were the low quality of forest fragments, crop losses through hurricanes, lack of access to information, low socioeconomic infrastructure and lack of gender equity. On the other hand, formal and informal social organization is a major strength. Crop losses due to drought or pests are not significant, but a more critical situation is foreseen in the face of climate change. Local efforts drive the main strategies to maintain a minimum level of resilience but will not be sufficient if unaccompanied by structural changes. [ABSTRACT FROM AUTHOR]

Sand drift erosion is common on aeolian landforms, particularly in the Gobi desert where sand drift is often quite strong. Sand drift erosion can lead to many types of hazards, including severe crop loss, structural damage to buildings or infrastructure, and abrasion of soil or clay components that contribute to the production of fine particulate matter. This article combines the Gobi sand flow model with the solid particles erosion model to simulate the sand drift erosion process in a variety of Gobi environments. The results show that the impact erosion of saltation particles is highly dependent on both the friction velocity and the gravel coverage. Saltation erosion amount increases with the increment of friction velocity and the gravel coverage. The vertical profile of saltating erosion rate displays a clear stratification pattern composed of a linear increasing layer, a damage layer, and a monotonic decreasing layer. The maximum value of the saltation erosion rate increases as the friction velocity increases and their curve shows a power-law relationship. The damage height caused by saltation erosion is primarily concentrated in the height range of 0.03 m to 0.15 m, and it increases approximately linearly with friction velocity. [ABSTRACT FROM AUTHOR]

The coffee berry borer, Hypothenemus hampei Ferrari (Coleoptera: Curculionidae, Scolytinae), is the most devastating insect pest of coffee worldwide. It feeds on the beans inside the berries leading to significant crop losses and unmarketable products. This study aims to model the impact of temperature on H. hampei fecundity and population growth parameters, as a contribution to the prediction of infestation risk. The fecundity was assessed on fresh coffee beans at six constant temperatures in the range 15–30°C, with RH 80 ± 5% and photoperiod 12:12 L:D. Nonlinear models were fitted to the relationship between fecundity and temperature using the ILCYM software. The best fecundity model was combined to development models obtained for immature stages in a previous study in order to simulate life table parameters at different constant temperatures. Females of H. hampei successfully oviposited in the temperature range 15–30°C, with the highest fecundity observed at 23°C (106.1 offspring per female). Polynomial function 8 model was the best fitted to the relationship between fecundity and temperature. With this model, the highest fecundity was estimated at 23°C, with 110 eggs per female. The simulated net reproductive rate (R0) was maximal at 24°C, with 50.08 daughters per female, while the intrinsic rate of increase (rm) was the highest at 26°C, with a value of 0.069. Our results will help understand H. hampei population dynamics and develop an ecologically sound management strategy based on a better assessment of infestation risk. [ABSTRACT FROM AUTHOR]