Pistachio nuts (cv. Mateur) quality and mycotoxin risks under rain-fed and irrigated organic and conventional farming systems in a warm arid area

Comparative biodiversity of insects and mites was studied in organic and conventional farming systems (FS) of tomato at certified organic farming unit of ASPEE College of Horticulture and Forestry (ACHF) and conventional farm of N. M. College of Agriculture (NMCA), Navsari Agricultural University, Navsari, Gujarat during 2018 – 2020, respectively. Total 1016 insect and mite individuals belonging to 9 insect and 1 mite orders, 14 insect and 2 mite families of 20 species of insects and 2 mites were recorded at organic farm (FS) against 967 individuals belonging to 8 insect and 1 mite orders, 13 insect and 2 mite families containing 17 insect and 2 mite species at conventional farm (FS). The diversity of insect and mites was higher in organic as compared to conventional FS. Higher species richness (22), species abundance (1016), species evenness (J= 0.76), species richness index (R= 3.03) and Shannon diversity index (H= 2.36) was observed at organic FS against lower species richness (19), species abundance (967), species evenness (0.69), species richness index (2.62) and Shannon diversity index (2.04) in conventional FS. Insect order Hemiptera and mite order Acarina were more represented at conventional farm (49.63 and 30.50 %) as compared to organic farm (46.99 and 24.17 %). Insects of Coleoptera order were more abundant at organic FS as compared to conventional FS. Relative abundance of herbivores was higher (82.10 %) with lower species evenness (0.71), species richness (1.20) and Shannon diversity index (1.55) in conventional FS as compared to lower relative abundance (69.68 %) with higher species evenness (0.74), species richness (1.37) and Shannon diversity index (1.71) in organic tomato FS. Similarly, 288 insect and mite predators were recorded at organic farm as compared to 161 individuals of insect and mite predators in conventional tomato FS. The relative abundance of predators was higher (28.30 %) with higher species evenness (0.70), species richness (1.59) and Shannon diversity index (1.64) at organic farm whereas, relative abundance (16.55 %), species evenness (0.67), species richness (1.59) and Shannon diversity index (1.64) remained lower at conventional farm. Similarly, higher parasitoids (21), relative abundance (2.02 %), species evenness (0.96), species richness (0.37) and Shannon weiner index (0.67) was observed in organic FS as compared to conventional FS (15, 1.52, 0.91, 0.34 and 0.63). In the present investigation, no pollinators were observed in both the farming systems.

Comparative insect and mite biodiversity studies were undertaken in organic and conventional Farming Systems (FS) of okra at certified organic farming unit of ASPEE College of Horticulture and Forestry (ACHF) and conventional farm of N. M. College of Agriculture (NMCA), Navsari Agricultural University, Navsari during 2016-2018. Total number of 1669 insect and mite individuals belonging to 10 insect orders and 1 mite order and 25 insect and 2 mite families of 32 species of insects and 2 mite species were recorded at organic okra farm against 1503 individuals belonging to 9 insect orders and 1 mite order and 22 insect and 2 mite families containing 26 insect and 2 mite species at conventional okra farm. The diversity of insect and mites was higher in organic okra farm as compared to conventional okra farm. Higher species richness (34 species), species abundance (1669), species evenness (J=0.81), species richness index (R=4.45) and Shannon diversity index (H=2.87) was observed at organic okra farm against lower species richness (28 species), species abundance (1503), species evenness (J=0.77), species richness index (R=3.69) and Shannon diversity index (H=2.57) in conventional okra farming system. Insect order Hemiptera and mite order Acarina were more represented at conventional farm (53.71 and 15.21%) as compared to organic farm (42.63 and 11.59%). Insects of Coleoptera (14.18 and 7.13%) and Hymenoptera (9.29 and 5.58%) were more abundant at organic farm as compared to conventional farm. Relative abundance of herbivores was higher (85.36%) with lower species evenness (J=0.77), species richness (R=2.24) and Shannon diversity index (H=2.18) at conventional farm as compared to lower relative abundance (72.86%) with higher species evenness (J=0.80), species richness (2.54) and Shannon diversity index (H=2.37) at organic okra farm. Similarly, 426 insect and mite predators comprising of 12 insect predators and 1 predatory mite species were recorded at organic farm as compared to 207 individuals of 8 species of insect predators and 1 predatory mites at conventional okra farm. The relative abundance of predators was higher (25.46%) with higher species evenness (J=0.84), species richness (R=1.99) and Shannon diversity index (1.93) at organic okra farm whereas, lower relative abundance (13.67%) with lower species evenness (J=0.76), species richness (R=1.50) and Shannon diversity index (H=1.84) were recorded at conventional okra farm. In the present investigation, no parasitoids were observed in both the farming systems. Species abundance and relative abundance of pollinators was also higher in organic okra as compared to conventional okra farming system. Higher abundance (39), relative abundance (1.68%), species evenness (J=0.93), species richness (R=0.31) and Shannon diversity index (H=0.63) were observed at organic okra farm as compared to lower abundance (28), relative abundance (0.97%), lower species evenness (J=0.81), species richness (R=0.27) and Shannon diversity index (H=0.54) of pollinators in conventional okra farming system. The lower Shannon diversity values indicate very low pollinator diversity in both organic and conventional okra farming systems.

The debate on the relative benefits of conventional and organic farming systems has in recent time gained significant interest. So far, global agricultural development has focused on increased productivity rather than on a holistic natural resource management for food security. Thus, developing more sustainable farming practices on a large scale is of utmost importance. However, information concerning the performance of farming systems under organic and conventional management in tropical and subtropical regions is scarce. This study presents agronomic and economic data from the conversion phase (2007–2010) of a farming systems comparison trial on a Vertisol soil in Madhya Pradesh, central India. A cotton-soybean-wheat crop rotation under biodynamic, organic and conventional (with and without Bt cotton) management was investigated. We observed a significant yield gap between organic and conventional farming systems in the 1st crop cycle (cycle 1: 2007–2008) for cotton (−29%) and wheat (−27%), whereas in the 2nd crop cycle (cycle 2: 2009–2010) cotton and wheat yields were similar in all farming systems due to lower yields in the conventional systems. In contrast, organic soybean (a nitrogen fixing leguminous plant) yields were marginally lower than conventional yields (−1% in cycle 1, −11% in cycle 2). Averaged across all crops, conventional farming systems achieved significantly higher gross margins in cycle 1 (+29%), whereas in cycle 2 gross margins in organic farming systems were significantly higher (+25%) due to lower variable production costs but similar yields. Soybean gross margin was significantly higher in the organic system (+11%) across the four harvest years compared to the conventional systems. Our results suggest that organic soybean production is a viable option for smallholder farmers under the prevailing semi-arid conditions in India. Future research needs to elucidate the long-term productivity and profitability, particularly of cotton and wheat, and the ecological impact of the different farming systems.

Keywords: environmental accounting, environmental indicators, farming systems, sustainability, organic farming, ecological-economic modelling, spatial analysis, multi-objective policy-making, opportunity cost. There is a growing awareness in present-day society of the potential of sustainable farming systems to enhance wildlife and the landscape and to decrease environmental harm caused by farming practices. EU commitment to integrate environmental considerations into agricultural political agenda has resulted in the adoption of environmental cross-compliance and agri-environment support schemes. Sustainability can only be achieved through multi-objective policy tools. Furthermore, more insight is needed into the environmental-economic tradeoffs of farming systems to direct policy interventions towards sustainable development of rural areas. The main objective of the present research is to provide an environmental-economic framework for the design and evaluation of agricultural policy schemes aimed at the operationalisation of sustainability in agricultural areas. The research involved designing and applying (1) an environmental accounting information system (EAIS), and (2) an integrated ecological-economic model to evaluate sustainability of farming systems. First, the EAIS together with a set of economic indicators was applied to three case study farms representing organic, integrated and conventional farming systems. Results showed that organic farming systems have the potential to improve the efficiency of many environmental indicators in addition to being remunerative. Environmental performances of all farming systems analysed were consistently affected by pedo-climatic factors on a regional as well as on a site scale. Subsequently, the EAIS indicators were integrated with farm records from one of the case studies and were used as a data source for the construction of an integrated ecological-economic model. The model was first used to evaluate the impact of current (Agenda 2000) and previous (MacSharry reform) agro-environment regimes on sustainability of organic farming systems. Then, the model was used to analyse the impact of Agenda 2000 common market organisation and agri-environment schemes on conventional and organic farming systems. Results indicated that the level of sustainability achieved with organic farming was satisfactory under both the MacSharry reform and the Agenda 2000 regulations. Optimising the model under different policy scenarios confirmed that organic farming systems are environmentally more beneficial than conventional farming systems. Combining the model with sensitivity and scenario analyses enabled an evaluation of the opportunity costs incurred by farmers to supply environmental amenities. Finally, the use of such information to back policy decisions is discussed.

Allophane is a characteristic of Andisols whose presence can absorb soil organic matter. One of soil organic matter fractions called the “labile fraction” is currently an appropriate indicator in determining soil quality. However, there is limited information concerning the relationship between allophane and the labile fraction. This study assessed the content of allophane by selective dissolution methods and calculated the labile fraction of particulate organic matter and microbial activity related to the carbon (C) and nitrogen (N) soil cycles in organic and conventional vegetable farming systems of two depths (0–25 cm and 25–50 cm). The content of the labile fractions of C and N in organic farming systems is higher than in conventional farming systems, which is also higher in the upper layer compared to the lower layer. However, the availability of allophane in the upper layer and organic system tends to be low. Therefore, allophane has a strong negative correlation with the labile fractions of carbon and nitrogen. The results of this study estimate that phosphorus (P) sorption is higher in soils containing quite high allophane. Hence, an organic farming system that has low allophane content will result in higher P availability for plants.

Phosphorous (P) is strongly adsorbed by soil components, such as soil organic matter and soil amorphous minerals in Andisols, which have been identified as an influential factor in adsorption and release of soil P. The aim of this study was to characterize the pattern of soil P adsorption and release in both organic and conventional vegetable farming systems in Merbabu Mountain area, Indonesia. Soil samples were collected from soil layers (0 cm to 20 cm and 20 cm to 40 cm) in organic and conventional farming systems. The result showed that the highest adsorption rate was found in organic farming systems at a depth of 20 cm to 40 cm. The lowest adsorption rate was found in conventional farming systems with low input of organic matter at a depth of 20 cm to 40 cm. A higher rate of P release was also found in organic farming systems with a low input of organic matter. It can be concluded that vegetable soils in organic farming systems are not only highly capable of adsorbing P but also capable of releasing P rapidly.

Deciphering soil resistance and virulence gene risks in conventional and organic farming systems

Evaluating the impacts of different wheat farming systems through Life Cycle Assessment

Application of organic farming system has been increased recently but change of soil properties due to organic farming system has not been thoroughly studied. The main purpose of this study was to compare physicochemical and biological soil properties between conventional and organic farming system and to identify the most affected soil parameters for two different farming system. Soil samples were collected from upland fields that have been using conventional or organic farming system for over five years. Then, physicochemical and biological soil properties were determined, including bulk density, porosity, pH, electrical conductivity (EC), cation exchange capacity (CEC), soil organic matter, total nitrogen (T-N), available phosphorus, soil respiration, and soil enzyme activities. For soil physical perspective, soils from organic farming system had lower bulk density and higher porosity values than conventional farming system. This result indicate that organic farming system had beneficial effect on soil physical properties. In case of soil chemical properties, the available phosphorus content in soil from conventional farming system was higher than in organic farming system probably due to the continuous use of inorganic fertilizers containing phosphorus in the arable area. For soil biological properties, β-glucosidase and phosphatase activities were higher under conventionally managed soils than organic farming system. Overall, physicochemical and biological soil properties can be varied depending on differently managed farming system and long terms of monitoring is necessary for understanding the change of soil properties between organic and conventional farming system.Soil properties including a) bulk density, b) soil organic matter content, c) β-glucosidase activity, and d) urease activity (CF, conventional farming; OF, organic farming).

Agricultural intensification is one of the major threats to global biodiversity and ecosystem services. Sustainable management of agricultural lands can reduce these impacts, but few efforts have been made in the context of paddy rice fields, especially in simplified landscapes composed of large monocultures separated by fragments of natural lands, such as in Taiwan or elsewhere in Asia. In this study, during a pest control intervention, we examined the effects of management practices on insect communities under conventional and organic farming systems in the paddy fields of northern Taiwan in 2016. Our results showed that organic practices did not increase the species richness or abundance of the four insect groups (total, predators/parasitoids, pests, and other insects). In addition, the composition of the insect communities did not differ between organic and conventional farming systems. Both the abundance and richness of predator/parasitoid insects were similar between conventional and organic farming systems. The pest abundance in the organic systems could be suppressed by other unmeasured predators and integrated management practices, which showed similar levels to the conventional systems with pesticide applications. The results of this study suggest that farming systems may not influence insect biodiversity in simplified landscapes during pest-control intervention.

Agriculture is a contributor of nitrate to natural waters and there is concern about the excess nitrogen burden loadings from agriculture on natural waters. Agricultural practices that reduce nitrate leaching from arable land are needed. It is postulated by certain groups that organic farming practices reduce nitrate leaching among other environmental benefits. The objectives of this paper are: (1) to compile, summarize and critically analyse information about NO3-N leaching from farming systems that were managed according to organic farming principles; (2) to compare NO3-N leaching from organic farming systems with that from conventional systems. This review consists of several parts. The available literature on leaching of NO3-N from organic farming and conventional farming systems was analysed. Leachable amounts of NO3-N in soils from two types of farming systems were compared. Finally NO3-N leaching from animal manure versus inorganic fertilizer was examined. In all studies we found in the literature, both the sequence and type of crops grown, and the input intensity of N was different in organic and conventional systems. Organic farming systems had on average a lower N input and more legumes in rotation. Average leaching of NO3-N from organic farming systems over a crop rotation period was somewhat lower than in conventional agriculture. If the different input intensities of N between organic and conventional systems were taken into account and corrected for, no differences in leaching losses between systems were found. However, a proper comparison of leaching between the two types of systems should take the yield into account. Attempting to do this in this review, we found only two studies which provided data for this. In both studies, specific conditions of the soil—a high organic matter content resulting in a high N mineralization at one site and a heavy clay texture resulting in very small leaching losses at the other site—did not enable us to come up with a clear-cut answer. Nevertheless, we could not find any evidence that nitrate leaching will be reduced by the introduction of organic farming practices, if the goal is to maintain the same crop yield levels as in conventional farming systems. Reduction of nitrate leaching is not a question of organic or conventional farming, but rather of introduction and use of appropriate counter- measures. This insight should guide our thinking when developing environmentally friendly and sustainable cropping systems.

Crop yield gap and stability in organic and conventional farming systems

Nitrogen (N) is the most important yield-limiting factor in agricultural systems, however, N application can lead to emissions and environmental problems such as global warming (N2O) and groundwater contamination (NO3 −). This study analyses the N balance, nitrogen-use efficiency, and N loss potential of conventional farming systems (arable farming, improved arable farming, and agroforestry) and organic farming systems (mixed farming, arable farming, and agroforestry) based on long-term field experiments in southern Germany. The effects of the conversion of farm structure and N management are identified. The conventional farming systems in this study were high N-input and high N-output systems. The conventional arable farming system had the lowest nitrogen-use efficiency and the highest N surplus. An optimised N management and the use of high-yielding crop varieties improved its nitrogen-use efficiency. The establishment of conventional agroforestry resulted in the reduction of N input, N output and N surplus, while maintaining high yields. The organic mixed farming system is characterised by a relatively high N input and N output, the accumulation of soil organic nitrogen, the highest nitrogen-use efficiency, and the lowest N surplus of all analysed systems. These good results can be attributed to the intensive farm N cycle between soil–plant–animal. The shift from organic mixed farming to organic arable farming system extensified the N cycle, reduced N input, crop yield and N output. The change from organic arable farming to organic agroforestry reduced the N input, increased the biomass yield, and remained the N surplus within an optimal range.

Horticultural production is an increasingly important activity in Senegal that is mainly located in the Niayes region between Dakar and St Louis. However, the increasing use of pesticides and inorganic fertilizers has many implications for the environment. The recognition that conventional horticulture might have a negative impact on farmers and consumers health, and on the atmosphere through the emission of GHGs, has increased in recent years, leading some NGO’s to promote organic farming. Therefore, the rising level of environmental hazards from conventional farming system made it attractive to farmers in the Niayes to adopt sustainable agriculture practices based on organic farming. A whole farm model is used to compare the economic and environmental performances of the organic and conventional horticultural farming systems in the Niayes region in Senegal. The gross margin is regarded as the economic indicator, while carbon emissions are regarded as environmental indicators. The results indicate that the conventional farming system is still more attractive than the organic farming because the sale price is the same for both systems. There is no market for organic food in the region. Simulation results also reveal that there exists a “win-win” situation for conventional farmers when they partially adopt organic farmingsystem. However, environmental results in terms of carbon emissions reduction suggest that the organic system is more effective in mitigating climate change. Our study suggests that, through appropriate investment in agro-ecological research to improve organic management and the establishment of a local market for organic crops, organic farming can become a competitive alternative to conventional farming, when it comes to healthy food production with less environmental impact in the horticultural sector. However, further studies are needed on components of sustainable intensification to see which system of production is more profitable for farmers of the Niayes region, but also beneficial for the environment, and at regional and even national levels.

Organic farming system and sustainable management of soil pathogens aim at reducing the use of agricultural chemicals in order to improve ecosystem health. Despite the essential role of microbial communities in agro-ecosystems, we still have limited understanding of the complex response of microbial diversity and composition to organic and conventional farming systems and to alternative methods for controlling plant pathogens. In this study we assessed the microbial community structure, diversity and richness using 16S rRNA gene next generation sequences and report that conventional and organic farming systems had major influence on soil microbial diversity and community composition while the effects of the soil health treatments (sustainable alternatives for chemical control) in both farming systems were of smaller magnitude. Organically managed system increased taxonomic and phylogenetic richness, diversity and heterogeneity of the soil microbiota when compared with conventional farming system. The composition of microbial communities, but not the diversity nor heterogeneity, were altered by soil health treatments. Soil health treatments exhibited an overrepresentation of specific microbial taxa which are known to be involved in soil suppressiveness to pathogens (plant-parasitic nematodes and soil-borne fungi). Our results provide a comprehensive survey on the response of microbial communities to different agricultural systems and to soil treatments for controlling plant pathogens and give novel insights to improve the sustainability of agro-ecosystems by means of beneficial microorganisms.