Agricultural Systems Research Articles

Reduced content of gamma-aminobutyric acid enhances resistance to bacterial wilt disease in tomato.

Bacteria within the Ralstonia solanacearum species complex cause devastating diseases in numerous crops, causing important losses in food production and industrial supply. Despite extensive efforts to enhance plant tolerance to disease caused by Ralstonia, efficient and sustainable approaches are still missing. Before, we found that Ralstonia promotes the production of gamma-aminobutyric acid (GABA) in plant cells; GABA can be used as a nutrient by Ralstonia to sustain the massive bacterial replication during plant colonization. In this work, we used CRISPR-Cas9-mediated genome editing to mutate SlGAD2, which encodes the major glutamate decarboxylase responsible for GABA production in tomato, a major crop affected by Ralstonia. The resulting Slgad2 mutant plants show reduced GABA content, and enhanced tolerance to bacterial wilt disease upon Ralstonia inoculation. Slgad2 mutant plants did not show altered susceptibility to other tested biotic and abiotic stresses, including drought and heat. Interestingly, Slgad2 mutant plants showed altered microbiome composition in roots and soil. We reveal a strategy to enhance plant resistance to Ralstonia by the manipulation of plant metabolism leading to an impairment of bacterial fitness. This approach could be particularly efficient in combination with other strategies based on the manipulation of the plant immune system, paving the way to a sustainable solution to Ralstonia in agricultural systems.

Evidence of horizontal transmission of Wolbachia wCcep in rice moths parasitized by Trichogramma chilonis and its persistence across generations

The horizontal transmission of endosymbionts between hosts and parasitoids plays a crucial role in biological control, yet its mechanisms remain poorly understood. This study investigates the dynamics of horizontal transfer of Wolbachia (wCcep) from the rice moth, Corcyra cephalonica, to its parasitoid, Trichogramma chilonis. Through PCR detection and phylogenetic analysis, we demonstrated the presence of identical wCcep strains in both host and parasitoid populations, providing evidence for natural horizontal transmission. To investigate thoroughly, Wolbachia-free colonies were acquired through tetracycline treatment, and the initial density of wCcep in host eggs significantly influences transmission efficiency. High-density wCcep infections led to rapid transmission, with F1 parasitoid titers increasing by as much as 100-fold, while low-density infections exhibited more gradual increases. Additionally, without continuous exposure to infected hosts, wCcep density in T. chilonis diminished over generations. These findings enhance our understanding of Wolbachia’s transfer dynamics and have important implications for developing effective and sustainable biological control strategies using parasitoid wasps, particularly in managing Wolbachia-related pest populations in agricultural systems.

Transformation towards Organic Cassava Production in Yasothon Province, Thailand

With the marked increase in consumer and commercial demand for organic foods and products, organic cassava production has become a viable alternative for small growers because it can lead to the sustainability of the agriculture and food production system. However, few studies have been conducted to enable a more comprehensive understanding of the factors that contribute to the transformation from chemical into organic cassava production systems. This study quantitatively aimed to identify socioeconomic, cassava profitability, and institutional factors that influence the cultural practice transformation towards organic cassava production in a district of Yasothon province, Thailand. We used a structured interview schedule to collect data from 283 sampled cassava growers comprising 236 chemical cassava growers and 47 organic cassava growers in the district during the period from August 2020 to November 2020. Quantitatively, we used the binary logistic regression method to identify the positive and negative factors contributing to the transformation of cassava production systems including growers’ motivations for the transformation. The study findings indicated that income from organic cassava was taken as the main motivation for growers’ decisions to transform (40.3%). We found that organic cassava farm gate price, access to formal credit, labor used and membership in growers’ organizations were positive significant factors that affected the cultural practice transformation. Finally, small cassava growers as well as stakeholders should systemically be considered by policymakers and in strategic intervention through relevant institutions.

Comparative Study of Power Tiller Operated Machines for Small Holders Farming in Conservation Agriculture

Timeliness is very crucial in all farm operations in general and in seeding and planting in particular. Slightly delay in sowing operation may lead to tremendous loss in production, productivity and sometimes quality of the grains followed by plant health. Power tiller operated machineries play very vital role for small scale farming system as the average holding size is close to one hectare and more than 86% of India’s farming community are small and marginal farmers. Practice of conservation agriculture with natural resource management has made the use of power tiller or hand tractors very essential for small holders farming. The power tiller with matching implements is cost effective source of farm power and it also enables farmers to diversify cropping pattern and increase in yield of crops. Present efforts were carried out to study the performance of various types of power tiller operated machines for different farm operations in conservation agriculture starting from seedbed preparation to crop harvesting for various crops like wheat, paddy, maize, gram, soybean, pigeon pea, sunflower, groundnut etc. Comparative field performance parameters such as field capacity, field efficiency, operating cost etc. and machine parameters have been presented in this paper.

Nitrate toxicity and health hazards: Problems and mitigation challenges

Abstract Nitrogenous fertilizers are considered an essential input for productive agriculture and the factor highly responsible for higher biomass production. Unfortunately, intensive mineral fertilization brings tremendous changes in soil fertility and productivity, but productivity decreases rapidly in cereal-based cropping systems or without legumes. The excessive use of mineral nitrogenous fertilizers reported an increase in potential health hazards and environmental problems such as groundwater contamination, eutrophication, acid rain, the greenhouse effect, and methemoglobinemia in humans. With future applications’ elevated use and prognosis, this problem may expand to several folds in the approaching decades. Large consumption of defiled water or food with higher concentrations of nitrates (according to the US Environmental Protection Agency (EPA), the permissible limit is 7 mg.kg −1 body weight per day) causes severe infant diseases such as Blue Baby Syndrome, respiratory ailments, gastric cancer, birth malformation and other health problems which earlier were rarely explained or explored worldwide. The unsustainable agronomic practices resulted in our soil being stripped of natural health and blind dependency on mineral fertilizers, ultimately leading to poor human and environmental health. There is an immediate need for new technologies related to farming systems to meet Sustainable Development Goals (SDGs) in view of changing climate. Various sustainable practices such as applying organic manures, precision N management, Soil Test Crop Response (STCR) approach, and nitrogen (N) inhibitors hold tremendous potential to reduce the ill effects of nitrates and secure the food chain if adopted on a large scale.

Impact of Stocking Density on Welfare, Behavior, and Growth Performance of Large White Yorkshire Pigs under Indian Condition

Aim: This study aimed to evaluate the effects of varying stocking densities on the welfare, behaviour, and production performance of growing Large White Yorkshire pigs. Study Design: The research focused on assessing the influence of decreasing floor space allowance per pig on welfare indicators, including behavioural patterns, growth metrics, and feed efficiency. Seventy-four weaned pigs were randomly divided into four treatment groups with stocking densities ranging from 0.3 m²/pig to 0.21 m²/pig. Behavioural data were recorded using smartphone cameras and CCTV, while growth and feed metrics were systematically measured. Place and Duration of Study: The experiment was conducted from 2020 to 2023 at the Piggery Farm, Department of Livestock Production Management, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, India (Latitude: 30°54' North, Longitude: 75°48' East). Methodology: A corn-soybean meal-based diet was provided ad libitum, and body weight, feed intake, and behavioural observations were recorded weekly. Negative and positive social behaviours, exploratory activities, and lying duration were documented for each group. Statistical analyses were performed using ANOVA and Duncan's Multiple Range Test to compare treatment effects at a significance level of P ≤ 0.05. Results: Growth performance, including body weight and average daily gain (ADG), showed no significant differences between groups; however, a linear increase in body weight was observed over time. Feed intake and feed conversion ratio (FCR) differed significantly, with pigs at higher stocking densities consuming more feed and displaying higher FCR values. Behavioural analysis revealed increased negative behaviours such as aggression and tail biting in higher stocking density groups, while exploratory and positive social behaviours were more frequent in these groups. Lower stocking density groups displayed more lying behaviour, particularly towards the end of the study. Conclusion: Decreasing floor space allowance significantly impacted pig behaviour, increasing stress-related activities and negative social interactions without significantly affecting growth performance. These findings emphasize the importance of optimizing space allocation in intensive pig farming systems to balance welfare and productivity.

Agroforestry Systems: A Pathway to Resilient and Productive Landscapes

Agroforestry, the integration of trees, crops, and livestock on the same land, offers a sustainable approach to enhancing agricultural productivity while mitigating environmental challenges. This review highlights the important role agroforestry systems play in promoting resilient and productive landscapes, particularly in the face of climate change, land degradation, and biodiversity loss. Agroforestry systems, including alley cropping, silvopasture, and home gardens, provide significant ecological benefits such as carbon sequestration, reduced greenhouse gas emissions, improved soil health, water conservation, and enhanced biodiversity. These systems not only stabilize microclimates and reduce soil erosion but also improve soil fertility and water infiltration, making them vital for climate adaptation. Socio-economically, agroforestry diversifies income sources for smallholder farmers by generating products like timber, fruits, and fodder, while contributing to food security through year-round crop availability and improved nutrition. Despite these benefits, the adoption of agroforestry faces substantial barriers, including socio-cultural resistance, knowledge gaps, inadequate policy support, and limited access to markets and credit. High initial costs, perceived risks, and competition for resources between trees and crops further impede its widespread implementation. Addressing these challenges requires enhancing extension services, policy reforms, financial incentives, and market access to support smallholder farmers. Future directions emphasize integrating agroforestry into national agricultural policies and climate action plans, supported by research on optimizing species selection, pest management, and sustainable resource use. By the synergies between agroforestry, regenerative agriculture, and Sustainable Development Goals, agroforestry presents a viable pathway for transforming agricultural systems into more resilient, productive, and sustainable models. Scaling up agroforestry can help restore degraded lands, sequester carbon, and enhance the livelihoods of rural communities, contributing to global efforts to combat climate change and promote sustainable development.

Nanotechnology for sustainability of agriculture and environment: Green synthesis and application of nanoparticles – A review

Moreover, with the continuous population increase worldwide, there is more demand of food and other daily necessities, which require double agriculture production to provide adequate food for humanity from the same available natural resources. Therefore, looking for new techniques to combat various challenges is instantly needed to sustain crop production and provide enough food for humanity. The use of nano-technology in agriculture field represents an important tool for consistent production of agriculture crops and assists farmers with new practice management systems such as precision agriculture systems, the aim of which is to increase productivity and reduce expenses. Nanotechnology plays an important role in altering agriculture food production. The particles ranging from 1 to 100 nm are accounted as nanoparticles, which usually have high surface energy, big surface area and quantum quarantine. Most notably, nanoparticles increase crop yield by increasing the effectiveness of agricultural inputs to enable site-targeted, controlled nutrient delivery, assuring the least amounts of agro-inputs needed. Additionally, the main aim in agricultural production is to facilitate plants' faster adaptation to the increasingly severe climate change factors, such as high temperatures, low water availability, salinity, alkalinity and environmental pollution with heavy metals, without jeopardizing the delicate ecosystems that are currently in place. This review illustrates the effect of numerous nanoparticles on diverse plants of many concentrations, sizes and shapes. The molecular and genetic response to NPs, their method of action and their interactions with biomolecules should be the main areas of study in the future.

Carbon removal potentials in agricultural systems – participatory scenario modelling with farmers in Sweden

Estimates of theoretical climate change mitigation potentials in agriculture need to be complemented with investigations of factors that influence deployment. This study introduces a framework for landscape-level assessment of climate change mitigation in agriculture that accounts for existing land uses, soil carbon stocks, and farmers’ preferences concerning specific mitigation options. The framework is used in an assessment of the deployment potentials for selected mitigation options in an agricultural landscape in Sweden, in which arable land covers approximately one-third of the land area. Three options were found to be preferable by farmers: biochar as soil amendment, cover crops, and (an increased) cultivation of ley crops in crop rotations. Cultivation of cover crops and leys was found to increase SOC stocks by 1.9 and 1.6 MgC ha−1 over three decades, respectively. About 10.2 MgC ha−1 is sequestered in soils over three decades when biochar is added as a soil amendment, if 50% of available residues are collected and utilized. This can be compared with GHG emissions from agriculture from the studied area, estimated at 1.6 Mg CO2-eq ha−1 yr−1 (GWP100). The framework was found useful for assessing mitigation options in the agriculture sector, underlining farmer involvement to identify actionable strategies.

Why do Farmers not Use Fertilizer? A Case of Multistorey Cropping System with Abaca under Coconut in Zamboanga Peninsula, Philippines

The Zamboanga Peninsula region significantly contributes to the Philippine coconut production, wherein abaca is also cultivated as an additional crop within coconut plantations. Still, coconut farmers belong to the country’s poverty sector. Abaca plays a significant role in providing an alternative source of income as a perennial intercrop in agroforestry systems like coconut. However, the productivity and sustainability of this farming system are affected by practices such as nutrient management, which is not explicitly known. Using a mixed-methods approach, this study applies a combination of quantitative and qualitative data-gathering techniques to assess the nutrient management practices adopted by the 33 qualified respondents, including challenges encountered and perceptions to abaca under the coconut farming system and fertilizer use. Quantitative data were analyzed using IBM SPSS Statistics version 29, and thematic analysis was utilized for qualitative data. Results indicate that most (88%) of the farmers in the area did not apply fertilizers for their abaca. Yet, they still consider abaca as one of the income-generating crops besides coconut. The lack of financial resources and irregular harvesting operations are significant challenges that hinder fertilizer application. Findings revealed the need to develop low-cost and practical nutrient management technology for abaca under coconut, which shall be complemented with an effective human resource management system of skilled harvesters for the continuous harvesting operation of abaca to translate good crop growth into good yield and income. This will serve as a basis for government institutions and other stakeholders in developing and implementing programs and policies to improve the abaca and coconut industries.

Toward a transdisciplinary and unifying definition of legacy phosphorus.

Legacy phosphorus (P) is a concept advanced by Dr. Andrew Sharpley and colleagues that was originally applied to the persistence of anthropogenic signatures in watersheds, and it has since been adopted in a diversity of settings to help guide the science and management of P. Following Sharpley's example to develop consensus-based science, we considered contrasting perspectives on legacy P and defined legacy P as those stores within the environment that arise from historic human activity excluding "natural" or "background" geogenic sources. Legacy P is not restricted to one system or setting; it may reside in soils, sediments, biota, and water bodies. Legacy P has been estimated by fluxes (inputs minus outputs of P to a system) or, equivalently, by mass stocks (total minus geogenic). Because the origin of P in the environment cannot currently be directly quantified, we recommend that researchers report "total P" to track wider watershed P stocks and fluxes of P that include legacy P. We recognize that the definition of legacy P will continue to evolve as we continue to work toward consensus. Ultimately, the final definition of legacy P has consequences for the implementation and success of regulatory and voluntary strategies for legacy P management in agricultural systems. We support continued progress toward a consensus-backed, research-grounded definition for legacy P that is widely applicable yet useful for guiding management and policy.

The Role of Psychological Capital on Climate Change Adaptation Among Smallholder Farmers in the uMkhanyakude District of KwaZulu-Natal, South Africa

Climate change and variability pose a challenge to the livelihoods of smallholder farmers. Previous studies on climate change in the context of smallholder farming have mainly focused on the influence of socio-economic factors in understanding farmers’ responses to climate change. However, little is known about the effect of psychological capital on climate change adaptation. There are calls for better empirical models and transdisciplinary approaches to understand the underlying drivers of climate change adaptation in smallholder farming systems. This study draws from behavioural decision research to assess psychological factors influencing climate change adaptation in the uMkhanyakude district of KwaZulu-Natal. This study adopted the Theory of Planned Behaviour to understand the effect of psychological capital on climate change adaptation. Data were collected from a sample of 400 smallholder farmers who were randomly selected from the uMkhanyakude district. Survey data were analysed using a multivariate probit regression model. The results of the multivariate probit regression model indicated that psychological capital (attitudes towards climate change, subjective norms, and trust) played an important role in influencing climate change adaptation. Climate change adaptation is also influenced by the gender of the farmer, education level, household size, and Tropical Livestock Units. These findings underscore the role of psychological capital in shaping climate change adaptation. This study recommends using transdisciplinary approaches (i.e., combining economics and psychology) in evaluating farmers’ responses to climate change.

Impact of leguminous crop residues on rice performance in diverse cropping systems in the alluvial soils of eastern Uttar Pradesh

In eastern Uttar Pradesh, the traditional rice-wheat cropping sequence has been identified as a factor contributing to unsustainable agricultural practices, resulting in low productivity and returns for small and marginal farmers. Crop diversification presents a viable solution to enhance productivity and ensure food and nutritional security for these farmers. A field experiment conducted under the All India Coordinated Research Project (AICRP) on Integrated Farming Systems (IFS) at Acharya Narendra Deva University of Agriculture and Technology, Ayodhya, U.P., India, from 2019-20 to 2021-22, evaluated the growth, yield attributes, and production potential of rice under ten rice-based cropping systems under irrigated medium-land conditions. The systems assessed included rice-wheat-fallow, rice-wheat-greengram, rice-frenchbean-greengram, rice-gram-cowpea, rice-mustard-greengram, rice-linseed-blackgram, rice-berseem-sudanchari, rice-oat-maize + cowpea, rice-cauliflower-okra, and rice-potato-cowpea (vegetable). The legume-based systems significantly enhanced plant height, which was attributed to the higher nitrogen availability from the decomposition of legume residues. Legume-based systems showed an increase in the number of leaves per hill and LAI, reflecting improved vegetative growth. Effective tiller production was higher in these systems, which contributed to superior panicle length, grain count, and grain weight. Among these systems, rice-frenchbean-greengram and rice-gram-greengram consistently outperformed the conventional system in terms of yield attributes and the yield of grain and straw. The integration of legume crops into rice-based sequences can improve soil fertility, promote better vegetative growth, and enhance yield, thereby contributing to more sustainable and productive rice cultivation.

Optimization of High-Density Planting Configurations for Poovan Banana (Musa spp.) in Coconut-Based Agroforestry Systems of the Cauvery Delta Zone

Bananas (Musa spp.) are a vital global agricultural commodity and an essential crop in tropical agricultural systems. The Poovan cultivar, known for its high productivity and adaptability, is particularly effective in intercropping within coconut-based agroforestry systems. This study investigates the impact of planting geometries on crop performance in the Cauvery Delta Zone by evaluating five spatial configurations, ranging from 2.1×2.1m to 0.9×0.9m, with a focus on morphological, physiological, and economic parameters. The results indicate that wider spacing configurations, especially 2.1×2.1m, significantly improve leaf morphological traits, including maximum leaf length (148.17 cm), breadth (77.75 cm), and leaf area index (2.61m²/plant). Additionally, these configurations enhance key fruit quality characteristics, such as increased bunch weight (16kg), improved fruit dimensions (20cm length), higher sugar content (22°Brix), and greater fruit firmness (4.5kg/cm²). The economic analysis suggests that a 1.5×1.5m spacing provides the most favorable cost-benefit ratio (1.14). This study offers valuable insights into the complex relationships between planting density, resource allocation, and productivity in tropical farming systems, providing evidence-based recommendations for optimizing both agricultural performance and economic viability in integrated farming systems.

Optimized Evaluations of Irrigation Profits and Balance of Irrigation Water Demand and Supply Under Climate Change

Optimizing irrigation profit is essential for enhancing agricultural productivity and ensuring sustainable water resource management, especially under the uncertainties caused by climate variability. It signifies that maximizing irrigation profits has become the primary consideration of current agricultural irrigation systems. By discussing the change in irrigation profits with irrigation fraction , which represents the proportion of irrigated farmland per unit area of cultivated land, a new method of qualitative diagnosis of irrigation supply and demand balance was proposed by means of the optimal irrigation fraction corresponding to the objective function and the correlation coefficient between irrigation water demand anomalies and irrigation water withdrawal anomalies (). It will serve as a new attempt to optimize irrigation profits. We argue that the optimal objective function represents the state of equilibrium of irrigation supply and demand. This study proposes a reverse optimization idea, which includes two comparison methods, to estimate the comprehensively optimal irrigation fraction that maximizes irrigation profits and irrigation profit per unit area while minimizing risks associated with climatic anomalies. By demonstrating that performs exceptionally well in meeting the objectives of maximizing irrigation profits and minimizing risks across various climatic scenarios, we suggest a robust method for optimizing irrigation profits, which simply calculates because is the function of . Since could capture the optimal solution to the greatest extent. It can serve as a simple and effective solution to determine the optimal objective function and diagnose the state of balance between irrigation water demand and supply. This method offers practical implications for water resource management and agricultural planning in the face of climate change.

Rate of Cross-Pollination at Different Isolation Distances between Grain Amaranth (Amaranthus hypochondriacus L.) and a Weedy Relative in Zimbabwe

The adoption of grain amaranth (Amaranthus hypochondriacus L.) as a climate-smart crop due to its hardiness and drought escape mechanisms in sub-Saharan Africa is under threat from the lack of pure seed due to contamination by weedy relatives, such as pigweed (A. hybridus L.). Due to limited land availability, proper isolation distances to attain seed purity in the small-scale farming sector are impossible. A study investigating the cross-pollination rate between grain amaranth and pigweed at distances between 3 and 150 m was conducted at three sites in Zimbabwe during the 2020/2021 and 2021/2022 rainy seasons. Grain amaranth was planted at radial distances of 3 to 150 m from the pure pigweed plot. Meteorological conditions, such as temperature and wind speed and direction, were measured during the anthesis period. The cross-pollination rate in grain amaranth was influenced by distance from the pollen source. A maximum cross-pollination rate of 12.9% was observed within a 10 m radius from the pollen donor plot, and a minimum outcrossing rate of 0.45% was recorded at 150 m. The complete removal of weedy relatives within an extrapolated distance of 325 m is recommended to maintain the genetic purity of grain amaranth in small-scale farming systems.

Profitability of Organic Versus Conventional Rice Production: An Evidence from South Asia

Rice, a staple and cash crop in South Asia, is vital for small-scale farmers, but concerns about the profitability of organic farming challenge its adoption despite its environmental benefits. The present study was conducted in the Rice-Wheat zone of three South Asian countries to make a comparison of profit efficiency in rice production under organic and conventional farming systems and to examine factors affecting profit efficiency. A multistage sampling technique was employed to collect cross-sectional data. Profit efficiency was determined by employing Cobb Douglas's functional form of stochastic profit frontier. Results show that the mean profit efficiency of organic rice growers is 0.89 less than conventional rice growers (0.910) in Pakistan. The mean profit efficiencies of organic growers are higher than conventional growers in Nepal and Bangladesh. Education and the role of the extension department are important factors in increasing the efficiency of organic and conventional farming while access to credit and experience in rice farming are significant in reducing inefficiencies in conventional rice farming. The study concludes that the education of farmers, the role of extension services, and easy credit access are key policy variables to improve profit efficiency.

Does Common Agricultural Policy Influence Regional Disparities and Environmental Sustainability in European Union Countries?

This study examines the impact of the European Union’s Common Agricultural Policy (CAP) funds, specifically the European Agricultural Fund for Rural Development (FEADR) and the European Agricultural Guarantee Fund (FEGA), on a range of economic, social, and environmental outcomes across European regions. Utilizing Fully Modified Ordinary Least Squares (FMOLS) estimators, this research analyses 13 equations corresponding to various dependent variables, including employment rates, poverty levels, agricultural productivity, and environmental indicators such as greenhouse gas emissions and renewable energy production from agriculture. This analysis covers the period from 2010 to 2021, and draws upon a balanced sample of 301 observations to ensure robust estimations. Results indicate that both FEADR and FEGA payments significantly influence these regional outcomes, though the effects vary depending on the specific economic or environmental indicator examined. The findings reveal that while FEADR payments positively impact rural employment, agricultural income, and renewable energy production, they are less effective in addressing poverty reduction and productivity enhancement. Conversely, FEGA payments exhibit a stronger influence on agricultural productivity and income, but have mixed effects on environmental sustainability. This study highlights significant regional disparities, suggesting that the allocation of CAP funds is uneven in its impact across regions. The implications for policymakers are clear: a more tailored approach is required to enhance the effectiveness of CAP funds in meeting diverse regional needs, particularly in promoting economic development while minimizing environmental harm. This study also emphasizes the need for further research to explore alternative policy mechanisms and innovative agricultural practices that can bridge the gaps identified in the current CAP framework. Limitations of this study include data availability and the inherent complexity of agricultural systems, which may affect the generalizability of the results across different EU member states.

A New Era in Federal Quarantine and State Certification Diagnostics at Clean Plant Centers in the USA.

Quarantine and certification programs exist to prevent the entry or spread of harmful pests and pathogens into agricultural systems. Their common objective is to identify pathogen-free source material through the application of validated testing methods for subsequent release for propagation. Tests must be accurate, efficient and cost-effective. In recent decades, the best tests have been biological assays in conjunction with PCR testing. High throughput sequencing (HTS) has now become a reliable and cost-effective diagnostic method having greater accuracy and efficiency than biological assays. In this article, we review the role of clean plant centers in quarantine and certification programs, as well as the process by which HTS was evaluated as a testing method to replace biological assays for screening source material. The data from this evaluation included a side-by-side comparison of HTS and biological assays for cultivars of grapevine, Prunus and rose, and intra- and inter-laboratory validations of an HTS protocol. Based on the results of these evaluations, in 2021 USDA-APHIS and several state regulatory agencies accepted the use of HTS and quantitative polymerase chain reaction (qPCR) to test new introductions of source material, replacing biological indexing. This new protocol requires testing at two timepoints within at least a six-month interval and a dormancy separating the two tests. Under ideal conditions, testing can be completed in 18-24 months with subsequent release from quarantine of plant material that has tested negative for regulated pathogens. This new testing protocol has a profound impact on quarantine and certification programs, facilitating quicker access of stakeholders to clean materials for propagation and increasing the number of pathogens that are detected, and even discovered, with reduced cost, effort, and time.

Residual Effects of Vinasse and Poultry Manure Application on Soil Quality and Spinach (Spinacia oleracea L.) Yield Grown in Calcareous Soil

Reuse poultry manure (PM) and vinasse (V) is a promising technology for the sustainability of various agricultural systems without environmental impact, but its effects on soil fertility index (SFI), hydraulic conductivity (Ks), porosity (TP), available water (AW), and spinach (Spinacia oleracea L.) growth in calcareous soils are poorly understood. Therefore, we studied the residual effect of combining PM either individually or mixed with V at different rates in pots. This study found that adding PM alone or in conjunction with V at various application rates resulted in an important improvement in SFI, Ks, TP, AW, and spinach yield. Vinasse contributed to an increase in more than 20% of the organic matter when adding it as 4.2 g V and 6.3 g PM kg−1 soil, and gave the best results in the organic matter fresh weight of spinach plant, SFI, and AW by 43.8%, 26.33%, 41.24%, and 63.63% compared to control. Spinach leaf uptake of NPK rose considerably when the soil was treated with PM alone or in combination with V. The SFI, cation exchange capacity (CEC), available N (AN), available P (AP), Ks, and AW were shown to be positively associated with spinach fresh weight utilizing principal component analysis, but soil electrical conductivity (EC), exchange sodium percentage (ESP), pH, and bulk density (BD) were found to be negatively correlated. Additionally, it was estimated by the K-Nearest Neighbors technique that under certain soil conditions, including AP 14.89 mg kg−1, AN 38.25 mg kg−1, microbial biomass carbon (MBC) 2.47 mg kg−1, CEC 11.66 cmol kg−1, exchangeable sodium percentage (ESP) 11.65%, and SFI 26.55%, spinach fresh weight increases to 13.8 t ha−1. These findings show how adding PM and V can improve soil quality and enhance nutrient uptake, all of which can contribute to a higher productivity of spinach and sustainability in calcareous soils.