Fertility and tillage intensity affect weed community diversity and functional structure in long-term organic systems.

Knowledge of how agricultural management interacts with weed seed banks and emergent weed communities is crucial for proactive weed management. Though studies have detailed how differences in disturbance and nutrient applications between organic and conventional herbicide-based systems affect weed communities, few have focused on these same factors in contrasting organic systems. This study assessed the seed banks and emergent weed communities from the most recent crop rotation cycle (2017-2022) of a long-term experiment, which compared four organic grain and forage cropping systems differing in nutrient inputs and soil disturbance. The high fertility (HF) system received high-rate nutrient applications, low fertility (LF) received low-rate applications, enhanced weed management (EWM) focused on weed control through frequent soil disturbance, and reduced tillage (RT) prioritized soil health with less intense or frequent soil disturbance. Soil samples for greenhouse germination assays were collected at the beginning (2017) and end (2022) of the rotation to explore how these four systems influenced seed bank dynamics over time. Weed community biomass was also sampled in each crop during this time. Treatment effects on weed abundance, taxonomic diversity, and community-weighted means and functional dispersion of weed traits were analyzed with generalized mixed-effect models. The RT system had the highest weed seed bank taxonomic diversity, and EWM had the lowest. RT and LF had higher functional dispersion of traits than HF in the seed bank. Weed seed bank communities in HF and RT were characterized by short, small-seeded, and early germinating weed species. However, seed banks were also labile: Differences between systems in seed density and all other mean trait values were dependent on the crop, which preceded seed bank sampling. Likewise, differences among emergent weed communities in the four systems depended on an interaction between crop species and their planting year. Results suggest that resource availability and intensity of disturbance act as weed community assembly filters in organic cropping systems. Organic growers seeking to design systems that balance weed management and production goals can use relatively low soil disturbance and nutrient application to increase weed community taxonomic or functional diversity without necessarily increasing weed biomass or seed bank density.

Investigation of the effects of melatonin application on storage in plums (Prunus domestica L.) grown under organic and conventional conditions.

This study was carried out to investigate the effects of melatonin applications on postharvest quality changes of organic and conventionally grown plum fruit. Melatonin was applied in 0, 50, and 100 µmol L- 1 for organic and conventional samples. The fruits were stored at + 2.0 °C and 90% relative humidity for 28 days. During the storage period, the color, weight loss, firmness, Soluble solids concentration (SSC), titratable acidity (TA), pH, total antioxidant content, and total phenolics were evaluated at 7-day intervals. While no effect of melatonin applications on weight loss of organically grown plums was observed, it was determined that weight loss decreased as the dose of melatonin increased in conventionally grown plums. The lowest weight loss during storage was determined in conventionally grown plums treated with 100 µmolL- 1 melatonin. It was observed that the firmness values decreased as the storage period increased in both cultivation methods. The firmness decreased as the dose of melatonin application increased in organically grown plums, while the firmness increased as the dose of melatonin application increased in conventional cultivation. Melatonin application did not positively affect SSC, pH, and color values. However, it was determined that the mean TA values decreased as the dose of melatonin increased in both cultivation methods. When the total phenol content of organic and conventional plums was examined, it was determined that melatonin application decreased the number of phenolic compounds. The highest phenolic content was determined in the control samples. The total amount of antioxidants was 1.71 µmol TE g- 1 on the 28th day in the highest (100 µmol L- 1) melatonin-treated conventionally grown plums.

Optimizing type, date, and dose of compost fertilization of organic cotton under climate change in Mali: A modeling study.

Adapting organic farming to climate change is a major issue. Cotton yields in Mali are declining due to deteriorating climatic conditions, soil fertility, and poor management. This study aimed to improve organic cotton yield in Mali in the future climate with the optimal choice of compost type, date, and dose of application. Experimental data collected in 2021 from the Sotuba research station in Mali was used for calibration and evaluation of the crop model DSSAT CSM-CROPGRO-Cotton model using phenology, leaf area index, and seed cotton yield. Climate data from the RCP4.5 and RCP8.5 scenarios of the GFDL-ESM2M model were used for future weather datasets for 2020-2039, 2040-2059, and 2060-2079. The model was able to simulate anthesis and maturity with excellent results, with nRMSE < 4%, and seed cotton yields moderately well, an nRMSE of 26% during calibration and 20.3% in evaluation. The scenario RCP8.5 from 2060 to 2079 gave the best seed cotton yields. Seed cotton yields with RCP4.5 and RCP8.5 were all better with the mid-May application period of small ruminant silo compost at 7.5 t/ha. In such conditions, more than 75% of the cases would produce more than 2000 kg/ha of seed cotton.

Normalized difference vegetation index analysis reveals increase of biomass production and stability during the conversion from conventional to organic farming.

Monitoring agriculture by remote sensing enables large-scale evaluation of biomass production across space and time. The normalized difference vegetation index (NDVI) is used as a proxy for green biomass. Here, we used satellite-derived NDVI of arable farms in the Netherlands to evaluate changes in biomass following conversion from conventional to organic farming. We compared NDVI and the stability of NDVI across 72 fields on sand and marine clay soils. Thirty-six of these fields had been converted into organic agriculture between 0 and 50 years ago (with 2017 as reference year), while the other 36 were paired control fields where conventional farming continued. We used high-resolution images from the Sentinel-2 satellite to obtain NDVI estimates across 5 years (January 2016-October 2020). Overall, NDVI did not differ between conventional and organic management during the time series, but NDVI stability was significantly higher under organic management. NDVI was lower under organic management in sandy, but not in clay, soils. Organic farms that had been converted less than ~19 years ago had lower NDVI than conventional farms. However, the difference diminished over time and eventually turned positive after ~19 years since the conversion. NDVI, averaged across the 5 years of study, was positively correlated to soil Olsen-P measured from soil samples collected in 2017. We conclude that NDVI in organic fields was more stable than in conventional fields, and that the lower biomass in the early years since the transition to organic agriculture can be overcome with time. Our study also indicates the role of soil P bioavailability for plant biomass production across the examined fields, and the benefit of combining remote sensing with on-site soil measurements to develop a more mechanistic understanding that may help us navigate the transition to a more sustainable type of agriculture.

Improving tomatoes quality in the Sahel through organic cultivation under photovoltaic greenhouse as a climate change adaptation and mitigation strategy.

Climate change negative impacts on food production systems have forced large scale food producers to make available less healthy products. Although available on the markets, tomatoes are no more tasting as they used to be and providing fewer nutrients compared to then. This study investigates and compares the quality and yield of organic tomatoes (Solanum lycopersicum) produced in an insect net covered photovoltaic greenhouse against ambient production. Plant's physical characteristics were measured, yields and nutrient content were found at harvest, and environmental conditions (temperature, relative humidity, solar irradiance and CO2) were recorded. Plants grew as high as 160 cm inside the greenhouse under an average afternoon temperature of 30.71 °C and a vapor pressure deficit (VPD) of 1.88 kPa against outside plant growth of 72 cm height under averages of 36.04 °C and 3.05 kPa. Although, inside greenhouse tomatoes were physically more attractive and firm with two times healthier tomatoes (98%), 52.39% higher content in protein, 13.31% more minerals and 13.19% more dry matter than outside tomatoes, the yield from outside environment was 4.57 times higher than that of inside due to probably the used crop variety adapted to the harsh climate. Using a crop variety optimum for greenhouse, increasing ventilation and using better fertilizers with enough irrigation could help increase productivity while keeping high fruit quality inside the greenhouse, leading to healthier fruits for food security in the Sahel.

Effects of natural oral alternatives to parental iron supplementation on haematological and health-related blood parameters of organic piglets.

The most common and efficient iron supply to prevent neonatal anaemia in piglets is the injection of iron dextran or gleptoferron. This treatment is problematic in organic farms because organic specifications strictly limit the use of chemically synthesised allopathic drugs. Based on the observation that piglets raised outdoors rarely develop anaemia, we hypothesised that piglets satisfy their iron needs by ingesting soil from their environment. Therefore, we compared the efficacy of a 100-mg intramuscular iron dextran injection (Iron, 8 litters, n = 98 piglets) at 4 days (d) of age (d4), to a daily ad libitum supply of dried soil (Soil, 8 litters, n = 101) or dried peat-like river silt (Peat, 8 litters, n = 102) from d4 to weaning (at 49 days of age, d49). Pigs were raised according to organic farming rules. Blood was collected on three males and three females per litter on d4, 20, 41, 50 and 69. BW was similar in the three groups on d4, 20, 41, 50 and 69 (P > 0.1). During the experiment, piglets were affected by a severe digestive E. coli episode but litter mortality rate between d4 and d69 did not differ between groups (P > 0.1). Blood haemoglobin concentration (Hb) was similar in all groups on d4, 50 and 69. However, on d20, Hb was higher in Peat and Iron groups than in the Soil group (P < 0.001), and on d41 and d50, Hb was higher in the Peat group than in Iron and Soil groups (P < 0.001). Mean red blood cell volume (RBCV) remained stable over time in the Peat group. In comparison, RBCV dropped in the Soil group on d20 and d41 (P < 0.001), and in the Iron group on d41 (P < 0.001). Soil and Iron group RBCV returned values similar to the Peat group by d69 (P > 0.1). In conclusion, soil supply in the pen was not sufficient to ensure a satisfactory iron intake in piglets, unlike peat-like river silt, which enable to reach haemoglobin concentrations above 80 mg/mL for over 90% of the piglets from d20 and, over 100% of piglets at weaning. The daily supply of the silt proved more efficient than the 100-mg iron injection beyond 20 days.

Biofungicides Based on Plant Extracts: On the Road to Organic Farming.

Phytopathogenic fungi are responsible for diseases in commercially important crops and cause major supply problems in the global food chain. Plants were able to protect themselves from disease before humans played an active role in protecting plants. They are known to synthesize a variety of secondary metabolites (SMs), such as terpenes, alkaloids, and phenolic compounds, which can be extracted using conventional and unconventional techniques to formulate biofungicides; plant extracts have antifungal activity and various mechanisms of action against these organisms. In addition, they are considered non-phytotoxic and potentially effective in disease control. They are a sustainable and economically viable alternative for use in agriculture, which is why biofungicides are increasingly recognized as an attractive option to solve the problems caused by synthetic fungicides. Currently, organic farming continues to grow, highlighting the importance of developing environmentally friendly alternatives for crop production. This review provides a compilation of the literature on biosynthesis, mechanisms of action of secondary metabolites against phytopathogens, extraction techniques and formulation of biofungicides, biological activity of plant extracts on phytopathogenic fungi, regulation, advantages, disadvantages and an overview of the current use of biofungicides in agriculture.

Soil fertility and plant nutrition in an organic olive orchard after 5 years of amendment with compost, biochar or their blend.

The agronomic use of compost and biochar as soil amendments may exhibit contrasting results in terms of soil fertility and plant nutrition. The effects of the biennial application of biochar, compost and a blend of compost:biochar (90:10; % dw:dw) on the agronomical performance of an organically managed and well established 25-year-old olive orchard was assessed 5 years after the initial application. The agronomical evaluation was based on the assessment of the soil physical, chemical, and biological characteristics, and the assessment of the soil fertility by both crop production and nutritional status of the orchard, and the bioassay with olive plantlets. Biochar mainly benefited the physical properties (bulk density, total porosity, aeration, water retention capacity) of soil, especially in the top 0-5 cm. Compost and its blend with biochar improved microbial activity, soil nutritional status (increasing the content of soluble organic C, N, and P) and favoured the formation of aggregates in soil. The bioassay conducted with young plantlets confirmed the enhanced soil fertility status in the three amended treatments, particularly in the case of biochar and its blend with compost. However, this effect was not significantly observed in the adult plants after 5 years of application, reflecting the slow response of adult olive trees to changes in fertilization. Based on these results, alongside the desirable long-residence time of biochar in soil and the ready availability of compost, the blend of biochar with compost assayed in this study is defined as a valid strategy for preparing high quality soil organic amendments.

Joint analysis of land, carbon and nitrogen reveals diverging trends in the sustainability of organic crops in Spain.

The world's top ten Organic Farming (OF) countries by converted area include several Mediterranean countries, including Spain. Despite this, little is known about the consequences of OF on crop production and environmental sustainability in this country. In this article, we conduct an agronomic analysis of Spanish considerable conversion rate to OF, which tends to concentrate in certain provinces and crops. Indeed, in the case of various crops and in several provinces, the organic share of total agricultural land exceeds 20-30 %. This concentration makes it possible to compare information obtained from farmers through interviews and provincial statistical information. The study data consisted of information collected from interviews of a representative sample of organic farmers conducted in 2004 and 2020 as well as official statistical information. The results showed that no yield gap between OF and conventional farming was found for vegetables and fruit trees, while it showed an increasing trend in arable crops. Presumably, the reason is that fruit trees and vegetables generate and incorporate high levels of carbon (C) flows into the soil and have a low land cost per unit of incorporated nitrogen (N) (or can be paid for), allowing to meet crop needs and to increase soil organic matter (SOM). Conversely, in the case of rainfed arable crops, the soil C and N inputs are deficient due to the low crop residues and the high land cost of N. Consequently, SOM destruction and N deficit progressively broaden the yield gap, undermining the agroecosystem sustainability. To reverse the situation, among other measures, it is necessary to implement agricultural policies designed to make rotations with high legume ratios viable and to plant varieties presenting higher production of residues and roots, such as traditional varieties.

Comparison of microbial diversity and metabolic activities in organic and conventional rice farms in Thailand.

Studies of the soil microbial community have revealed that several factors, both biotic and abiotic, can influence the community structure, diversity, and function. Human agricultural practice has been one of the key factors that affect microbial structure in soil. In this study, we examined the effect of two rice farming practices (i.e., conventional and organic) on soil microbial diversity and their metabolic activities. We proposed that the use of herbicides and chemical fertilizers in the conventional rice farming may decrease the soil microbial diversity and that it may lead to a decline in soil quality. However, our results show that there is no significant difference in the soil chemical properties, microbial diversity, and microbial metabolic activities between the two agricultural management systems. The wetland water cycling regime of rice agriculture in Thailand perhaps prevents the accumulation of chemicals in the soil, thus subdue the effect of these chemicals on soil microbes. Furthermore, our results showed that the key determinant of soil chemical properties as well as microbial community structure and diversity is the soil physical property, while the farming activity influences the microbial metabolic functions. These findings indicate the complex nature of the soil, microbes, and human farming interactions.IMPORTANCERice is a major export commodity in Thailand. As such, an understanding of the effect of conventional or organic farming approaches on soil microbial community could enable a suitable farming management. In this study, microbial communities were surveyed and compared between the two rice farming practices for their diversity and metabolic activities. Results showed no significant differences in microbial community structure and diversity between the two rice farming practices, but significant differences were observed due to the soil type, namely, clay, silty clay, silty clay loam, loam, and silty loam. Interestingly, significant differences in metabolic functions were also observed in different soil farming activities, such as land rest, period of growth, and post-burning, but not due to conventional or organic practices. These findings showed that the soil physical type and the farming activity impact the microbial community more than whether it is conventional or organically farmed.

Effects of 3-year organic farming management on soil antibiotic resistant genes and virulence factors in a double rice cropping system.

Investigating the antibiotic resistance genes (ARGs) and virulence factors (VFs) within soil microbial communities is crucial for understanding microbial ecology and the evolution of antibiotic resistance. However, the study of ARGs, VFs, and their predominant microbial hosts in soils under varying rice production management practices remains largely underexplored. To this end, a three-year field experiment was conducted under organic management within a double rice cropping system in South China. The study revealed that, in contrast to conventional management (CK), organic farming practices did not significantly alter the total reads of ARGs and VFs. However, there was a notable alteration in the ARGs abundance at the antibiotic class level, such as an increase (P < 0.05) in the abundance of Multidrug ARGs (by 1.7 %) and a decrease (P < 0.05) in Rifamycin (by 17.5 %) and Fosfomycin ARGs (by 15.3 %). Furthermore, a significant shift in VFs was observed under organic farming compared to CK, characterized by an increase (P < 0.05) in offensive VFs and a decrease (P < 0.05) in nonspecific VFs and the regulation of virulence-associated genes. Key microbial taxa identified as influencing ARGs and VFs in the tested soil samples, e.g., Proteobacteria. The findings highlight the need for more detailed attention to soil ecology within organic rice production systems in South China, particularly concerning the significant alterations observed in ARGs and VFs.

Feeding strategy in organic pig farming as a lever to improve various quality dimensions of pork.

Since 2022, European specifications for organic pig farming have evolved to distribute 100 % organic feed and to reinforce the link to the soil with feed resources that should primarily be obtained from the farm or the same region. Feeding strategy acts as a lever to improve various quality dimensions of organic (as well as conventional) pork, including intrinsic dimensions (carcass composition, nutritional, organoleptic, technological, sanitary qualities) and extrinsic dimensions related to animal farming (image). Diet may also influence the risk of undesirable odours or flavours that may be found in pork from non-castrated male pigs. This study aimed at evaluating the effects of a specific feeding strategy on several quality dimensions of organic meat from non-castrated male pigs. The experiment was conducted with 77 organic non-castrated male pigs (Piétrain NN × Large White) reared according to organic specifications and distributed in two batches. Within litters, male littermates were allocated at around 33 kg of live weight to either a Control group which received a Control feed (C) corresponding to the organic specifications or in a Bio+ group which received an organic test feed based mainly on French raw materials and which contained more fibres (faba bean and access to forages) and omega-3 fatty acids (linseed, camelina). All pigs were reared in the same building on deep straw bedding (1.3 m2/pig) with free outdoor access (1.0 m2/pig) using one pen per experimental group. Pigs were fed ad libitum until slaughter at about 125 kg live weight. Average daily gain, carcass weight and lean meat content did not differ significantly between C and Bio+ pigs. Compared to C, Bio+ pigs had higher (P < 0.05) ultimate pH in the loin (Longissimus muscle) and ham (Gluteus medius, and Semimembranosus) muscles, associated with a lower Longissimus muscle glycolytic potential (P < 0.001). Loin and ham meat from Bio+ vs. C pigs was lighter (P < 0.05) and had a more intense red colour (P < 0.10). The Bio+ strategy led to a lower Longissimus muscle n-6:n-3 fatty acid ratio (P < 0.001), indicating an improvement in pork nutritional value. Backfat skatole concentration was lower in Bio+ than in C pigs whereas backfat androstenone was higher in Bio+ than in C pigs (P < 0.05). Altogether, we demonstrated that the Bio+ strategy had positive impacts on several qualities of organic pork from non-castrated male pigs.

Harnessing the Power of Traditional Organic Formulations for Crop Growth and Microbial Harmony.

The utilization of various agrochemicals in crop production technology leads to soil health and fertility depletion. Multiple measures have been taken to revitalize the health of polluted soil. In this context, organic agriculture has increased over the past few years to overcome the detrimental effects of extensive modern agricultural practices. Several traditional organic formulations, such as panchagavya, jeevamurtha, beejamurtha, bokashi, etc., are vital in converting polluted farmlands into organic. Various countries have their own organic formulations to improve crop growth and yield. These formulations are rich sources of many macro and micronutrients, growth-promoting phytohormones, and provide resistance against biotic and abiotic stresses. Apart from these benefits, these formulations consist of several groups of beneficial microorganisms that belong to the phyla Proteobacteria, Firmicutes, Bacteroides, and Actinobacteria, while some of the novel groups of microorganisms were also reported from the ingredients used in the preparation of these organic formulations. These microorganisms can solubilize nutrients such as phosphorous and zinc, oxidize sulfur, reduce nitrate, and are also involved in the production of indole acetic acid, ethylene reduction enzyme (1-aminocyclopropane-1-carboxylic acid deaminase), and organic acids that promote plant growth and induce resistance in the plant system. Hence, the utilization of traditional organic formulations helps in the reclamation of environmental health without compromising crop yields. This review describes the importance of organic farming, the preparation and application of different types of traditional organic formulations in different countries, and the microbial composition and mechanism of growth promotion of different traditional organic formulations.

Pomegranate Rhizosphere Microbial Diversity Revealed by Metagenomics: Toward Organic Farming, Plant Growth Promotion and Biocontrol?

Food production must undergo systems change to meet the sustainable development goals (SDGs). For example, organic farming can be empowered by soil microorganisms with plant growth promotion (PGP) and biocontrol features. In this context, there have been limited studies on pomegranate. We investigated microbial diversity in rhizosphere of the pomegranate "Bhagwa" variety and its potential role in PGP and biocontrol. Both bulk and rhizosphere soil samples were analyzed for their physicochemical properties. Whole metagenome sequencing was conducted using the Illumina NovaSeq6000 platform. Surprisingly, we found that bulk and rhizosphere soil samples had comparable microbial diversity. Metagenome sequencing revealed the abundance of Streptomyces indicus, Bradyrhizobium kalamazoonesis, and Pseudomonas cellulosum in the rhizosphere that are reported here for the first time in agricultural literature. Pathway prediction analysis using KEGG (Kyoto Encyclopedia for Genes and Genomes) and COG (clusters of orthologous genes) databases identified metabolic pathways associated with biocontrol properties against pathogens. We confirmed the metagenome data in vitro, which demonstrated their PGP potential and antimicrobial properties. For instance, S. indicus produced high concentration of indole-3-acetic acid, a PGP phytohormone, that can stimulate plant growth. In addition, an antimicrobial susceptibility assay suggested that bacterial extracts displayed activity against Xanthomonas, a primary pathogen causing the pomegranate wilt disease. In conclusion, this study suggests that S. indicus, B. kalamazoonesis, and P. cellulosum can potentially be PGP and biocontrol agents that may contribute to increased crop productivity in pomegranate cultivation. These agents and their combinations warrant future research with an eye on SDGs and so as to enable and innovate organic farming and pomegranate agricultural practices.

Organic farming reduces pesticide load in a bird of prey.

Human activities have led to the contamination of all environmental compartments worldwide, including bird species. In birds, both the environment and maternal transfer lead to high inter-brood variability in contamination levels of pollutants, whereas intra-brood variability is generally low. However, most existing studies focused on heavy metals or persistent compounds and none, to our knowledge, addressed the variability in contamination levels of multiple pesticides and the factors influencing it. In this study, the number of pesticides detected (of 104 compounds searched) and the sum of their concentrations in the blood of 55 Montagu's harrier (Circus pygargus) nestlings from 22 nests sampled in 2021 were used as metrics of contamination levels. We investigated the effect of organic farming at the size of male's home range (i.e., 14 km2) and chicks' sex and hatching order on contamination levels. We did not find a difference between inter-brood and intra-brood variability in pesticide contamination levels, suggesting a different exposure of siblings through food items. While chicks' sex or rank did not affect their contamination level, we found that the percentage of organic farming around the nests significantly decreased the number of pesticides detected, although it did not decrease the total concentrations. This finding highlights the potential role of organic farming in reducing the exposure of birds to a pesticide cocktail.

The fruit quality and nutrient content of kiwifruit produced by organic versus chemical fertilizers.

BACKGROUND: Currently, organic farming has become a feasible approach for the production of high-quality fruits. To evaluate the response of fruit quality and mineral nutrition contents of Hayward Kiwifruit affected by different organic and inorganic fertilizers, the present study was conducted in Citrus and Subtropical Fruits Research Center, Iran, in 2017-2021, as a randomized block design with three replications. The studied treatments were organic fertilizers (cow, vermicompost and Azolla) and chemical fertilizers. After 4 years of fertilization, the fruit's nutritional elements content and some fruit bioactive compounds were evaluated after 3 months of cold storage and then analyzed by the principal component analysis (PCA) method. RESULTS: The use of organic amendments boosted the calcium, phosphorus, potassium and iron content of the kiwifruits compared to chemical fertilizers. The highest fruit potassium and phosphorus content were recorded in the cow manure treatment. The lowest amount of nitrate and the highest calcium, zinc, copper and manganese accumulation were recorded in the fruits treated with vermicompost. In addition to mineral nutrients, the dry matter, total soluble solids, total phenolic and antioxidant capacity of kiwifruit were improved by the application of vermicompost amendment compared to the other fertilizer sources. However, the highest fruit vitamin C and total soluble carbohydrates were measured in the cow manure treatment. The PCA results of the fruit quality indices indicated that fertilization treatments were ranked as vermicompost (1.88) > cow manure (1.63) = chemical (1.60) > Azolla (1.54). CONCLUSION: It is concluded that the application of 40 kg of vermicompost or 40 kg of cow manure in the next rank in Hayward kiwifruit orchards in March (growth stage beginning of bud swelling) may be a more suitable approach for improving the nutritional quality of the fruit. © 2024 Society of Chemical Industry.

Fruit quality in organic and conventional farming: advantages and limitations.

Fruit quality is essential for nutrition and human health and needs urgent attention in current agricultural practices. Organic farming is not as productive as conventional agriculture, but it can provide higher quality in some fruit crops, thanks to the absence of synthetic fertilizers and pesticides, enhanced pollination, and the reduction of protection treatments, hence boosting antioxidant compound production. Although organic farming does not always provide healthier food than conventional farming, some lessons from organic farming can be extrapolated to new sustainable production models. Exploiting natural resources and an adequate knowledge transfer will undoubtedly help improve the quality of climacteric and nonclimacteric fruits in new agricultural systems.

Anaerobic Soil Disinfestation and Vermicompost to Manage Bottom Rot in Organic Lettuce.

Rhizoctonia solani Kühn (teleomorph: Thanatephorus cucumeris [Frank] Donk) is an aggressive soilborne pathogen with a wide host range that survives saprophytically between crops, presenting a challenge for organic vegetable farmers who lack effective management tools. A 2-year field experiment was conducted at two organic farms to compare anaerobic soil disinfestation (ASD) and worm-cured compost (vermicompost) to manage bottom rot caused by R. solani subspecies AG1-IB in field-grown organic lettuce (Lactuca sativa). At each farm, four replicate plots of seven treatments were arranged in a randomized complete block design. Randomization was restricted by grouping treatments to evaluate ASD, and treatments to evaluate vermicompost in starter plugs. ASD experiment treatments were three different ASD carbon sources that are commonly used and widely available to local farmers in Vermont: compost, cover crop residues, and poultry manure fertilizer, as well as a tarped control. Vermicompost experimental treatments were vermicompost compared with two types of controls: a commercial biocontrol product (RootShield PLUS + G), and unamended (untarped control). This study demonstrated that the ASD method is achievable in a field setting on Vermont farms. However, neither ASD nor vermicompost produced significant disease suppression or resulted in higher marketable yields than standard growing practices. Given the laborious nature of ASD, it is likely more appropriate in a greenhouse setting with high-value crops that could especially benefit from being grown in plastic tarped beds (e.g., tomatoes and strawberries). This study is the first known attempt of field-implemented ASD for soil pathogen control in the northeastern United States.

Exploring membrane vesicles in citrus fruits: a comparative analysis of conventional and organic farming approaches.

BACKGROUND: Recently, vesicles derived from plant cell membranes have received attention for their potential use as active biomolecules and nanocarriers, and obtaining them from organic crops may be an interesting option because different farming systems can affect production, plant secondary metabolism and biochemistry of cell membranes. The present study aimed to determine how organic and conventional farming affects the mineral nutrition, gas exchange, CO2 fixation and biochemical composition of lemon fruits, which could have an impact on the different fractions of cell membranes in pulp and juice. RESULTS: Organic trees had higher intrinsic water use efficiency (WUEi) but conventional trees had higher stomatal conductance (gs) and nitrogen use efficiency (NUtE). Also, organic lemons had significantly higher levels of some micronutrients (Ca, Cu, Fe and Zn). Second, the main differences in the membrane vesicles showed that organic pulp vesicles had a higher antioxidant activity and more oleic acid, whereas both types of vesicles from conventional lemons had more linoleic acid. CONCLUSION: In conclusion, organic farming did not alter carbon fixation parameters but impacted nitrogen fixation and water uptake, and resulted in higher micronutrient levels in lemons. These mineral nutritional changes could be related to the higher production of membranes that showed suitable morphological traits and a high antioxidant activity, positively correlated with a high amount of oleic acid, which could have stronger cell protection characteristics. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.