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Cassava (Manihot esculenta Crantz) is a major staple food in many developing countries, including Brazil. However, it faces significant challenges due to diseases such as dry root rot (DRR) and black root rot (BRR) caused by soil-borne plant pathogenic fungi. This study explored the use of cover crops to suppress these diseases and to improve the agronomic traits of cassava. Over four cultivation cycles, various cover crops (sunn hemp, black oat, jack bean, maize, peanut and cowpea) were alternated with cassava varieties 'BRS Kiriris' (resistant) and 'BRS Formosa' (susceptible) in soil infested with DRR (Fusarium oxysporum, F. equiseti, F. verticillioides, F. solani, F. lateritium, F. chlamydosporum) and BRR (Lasiodiplodia theobramae, Neoscytalidium dimidiatum) pathogens. In the 2nd cycle, only germination showed significant differences, but by the 4th cycle, various agronomic parameters, including fresh weight (FW.AP), dry weight (DW.AP) of the aerial part, fresh weight (FW.Root), dry weight (DW.Root) of the roots, and plant vigor. Cowpea was identified as the most effective cover crop for reducing the disease index (DI %) by promoting healthier and taller cassava plants. Jack beans and peanuts also had positive effects on vigor, FW.AP, DW.AP, FW.root, and DW.root. In contrast, maize, black oats, Crotalaria ochroleuca, cassava, and fallow soils had minimal impacts. Throughout these cycles, the selected cover crops consistently contributed to disease reduction and improved the agronomic performance of the cassava. This study highlights the potential of holistic disease management strategies. [ABSTRACT FROM AUTHOR]

Farming management and alterations in land cover play crucial roles in driving changes in biodiversity, ecosystem functioning, and the provision of ecosystem services. Whereas land cover corresponds to the identity of cultivated/non-cultivated ecosystems in the landscape, farming management describes all the components of farming activities within crops and grassland (i.e., farming practices, crop successions, and farming systems). Despite extensive research on the relationship between land cover and biodiversity at the landscape scale, there is a surprising scarcity of studies examining the impacts of farming management on biodiversity at the same scale. This is unexpected given the already recognized field-scale impact on biodiversity and ecosystem services, and the fact that most species move or supplement their resources in multiple patches across agricultural landscapes. We conducted a comprehensive literature review aimed at answering two fundamental questions: (1) What components of farming management are considered at the landscape scale? (2) Does farming management at the landscape scale impact biodiversity and associated ecosystem functions and services? We retrieved 133 studies through a query on the Web of Science, published from January 2005 to December 2021 addressing the broad notion of farming management at the landscape scale. The key findings are as follows: (1) The effect of farming management components at the landscape scale on biodiversity was tackled in only 41 studies that highlighted that its response was highly taxon-dependent. They reported positive effects of organic farming on pollinators, weeds, and birds, as well as positive effects of extensification of farming practices on natural enemies. (2) Most studies focused on the effect of organic farming on natural enemies and associated pests, and reported contrasting effects on these taxa. Our study underscores the challenges in quantifying farming management at the landscape scale, and yet its importance in comprehending the dynamics of biodiversity and related ecosystem services. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the no-tillage system (NT) with different implantation times and vegetation cover on changes in the chemical and structural compositions of soil humified organic matter. Five areas with different NT management histories were studied; for 6 (NT6), 14 (NT14), 22 (NT22) years with succession of soybean/corn crops; for 12 years and 4 more years with corn and Brachiaria (NT+B), pasture for 39 years and native forest. Soil samples were collected at the depths of 0.0–0.05 and 0.05–0.10 m. The changes in the quality of humic acid (HA) were evaluated by several chemical techniques (total organic carbon (TOC), fulvic acid fraction (FA), humic acid fraction (HA) and humin fraction (HU), ionizable functional groups, elemental composition) and spectroscopic techniques (UV–Vis absorption, fluorescence, and Fourier transform mid-infrared photoacoustic spectroscopy, called FTIR-PAS). On the surface, the TOC, carbon of the HA and HU fractions, total acidity, phenolic acidity, Carbon, Nitrogen, Sulfur, Hydrogen and Hydrogen/Carbon ratio were higher in the areas of forest, pasture and NT22. On the subsurface, the responses are the same as on the surface. However, the NT22 system presents higher FA, HA, carboxylic acidity and humification degree (HD). UV–Vis absorption spectroscopy, fluorescence spectroscopy and FTIR-PAS can discriminate soils under different managements and under natural conditions. Agronomic practices have strongly affected the soil organic matter, in which the NT promotes the formation of HA with characteristics closer to those of the forest, as the implantation time increases, such as 22-year-old NT and pasture. This indicates that care must be taken in managing the no-till system to maximize its potential to promote stabilization of organic matter, thereby contributing to carbon sequestration. The humic substances contribute as sustainability indicators in agriculturalsystems Were evaluated no-tillage system (NT) with different implantation times. The UV–Vis, fluorescence and FTIR-PAS discriminate soils under different managements. NT promotes humic acid formation with characteristics closer to those of the forest. [ABSTRACT FROM AUTHOR]

Background: Durum wheat is the most important cereal in Algeria. The yield of durum wheat is low and depends on climatic conditions and technical operations. Methods: The objective of this study is to compare the effect of the no-till system (NT) and conventional tillage system (CT) with three crop rotation sequences on wheat yield, yield components and some physiological traits under rain-fed conditions. The study was conducted at the technical institute of field crops-Sétif-in east of Algeria, over three crop seasons: 2016/17, 2017/18 and 2018/19. Result: The number of plants/m², tillers/m², spikes/m² and grain yield were affected by the tillage system and the environmental conditions. Seed weight, straw yield, biological yield, leaf relative water content and leaf chlorophyll content were significantly affected by the environment but not by the tillage system. While the spike density, the harvest index and the grain yield were significantly higher under NT system than in the CT system. Furthermore, wheat grain yield was also higher following legumes than in wheat monoculture. These results indicate that no-tillage and crop diversification by adding leguminous in rotation improves grain legumes yield of durum wheat under semi-arid conditions of Algeria. [ABSTRACT FROM AUTHOR]

This study applied the Gebre optimization model to optimize the land and water usage in the Omo-Gibe river basin, Ethiopia, where competition among stakeholders and growing demands pose a challenge. This model was applied through a nexus approach to maximize benefits and minimize conflicting trade-offs. The main objective was to maximize the economic benefit from land and water allocation with the framework of the land-water-food-energy-environment nexus under climate change mitigation and river ecosystem services (LWFEEN). This model takes into account multiple dimensions, including economic, environmental, social, and technical factors, going beyond ordinary optimization models. It also incorporates an innovative crop succession allocation concept not often seen in the literature. This crop succession proposal includes sequences of cropping patterns and fallow land use options that closely resemble real-world farming practices. The results demonstrated that the Gebre optimization model effectively resolves the existing constraint conflicts and maximizes economic benefits by reducing costs, penalties, and environmental impacts, promoting sustainable use of natural resources in the Omo-Gibe river basin and avoiding conflicts among stakeholders. Therefore, this study offered decision-makers a strategic perspective on how to apply the Gebre-model within the context of the land-water-food-energy-environment nexus(LWFEEN) approach in river basins such as the Omo-Gibe, with the ultimate goal of achieving sustainable development. [ABSTRACT FROM AUTHOR]

The importance of plant richness to enhance the presence, biodiversity and efficiency of natural enemies in agricultural systems has largely been studied and demonstrated these last decades. Planting and preserving non-crop plants or manipulating crop richness in fields are practices that have proven their efficiency. However, the impact of crop-richness continuity in space and time on pests and natural enemies at a landscape scale remains poorly studied. In a two-year study, we assessed the effect of crop richness (single crop vs. multiple crops) on pest and natural enemy abundance and spillover in a field experiment in north-east China. Overall, we found crop diversity had a limited impact on pest and natural enemy abundance at the spatial scale tested (0.025 vs. 0.2 ha). The total pest and natural enemy abundances were not different between single-crop and multi-crop plots in either year, and the community composition at the functional group level was mostly determined by the crop but not crop diversity. However, we found that crop diversity influenced the numeric response of ladybirds to aphids in wheat; their negative response (higher abundance where aphid abundance was lower, suggesting predation) was attenuated in multi-crop plots (no correlation of aphid and ladybird abundance, suggesting the use of alternative resources). This pattern was not found in maize. Finally, crop succession enhanced the spillover of ladybirds from wheat and maize to cotton plots but with limited benefits for aphid control. Because of these limited impacts, we hypothesized that crop diversity may benefit natural enemy populations and enhance pest control at larger spatial scales; while we found similar abundances of ladybirds between our small (0.025–0.2 ha) plots and in large (2 ha) close-by cotton fields, aphid abundances were more than ten times higher in large cotton fields. Our study highlights the need to accurately estimate the spatial scale at which crop biodiversity may benefit pest control, in relation to the ecology of the target pest and natural enemies. [ABSTRACT FROM AUTHOR]

A considerable body of evidence has demonstrated the positive impact of the diversity of plant species on biological control of pests at the field scale. However, very few studies have assessed the effect of crop diversity on natural enemy performance and pest control. In order to test our hypothesis that crop diversity could increase natural enemy development and performance, we examined the mechanisms underlying the effect of two types of crop succession, i.e., multiple-crop succession (tomato, squash and soybean) and mono-crop succession (each crop alone), on population dynamics, predation capacity and spillover of Nesidiocoris tenuis Reuter (Hemiptera: Miridae) in a greenhouse experiment. We found that (1) the polyculture supported lower population growth of N. tenuis and lower predation rates of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs compared to tomato and squash monocultures, but that correspondingly (2) the predator performed better on the polyculture than on the soybean monoculture. These results revealed that crop identity within the succession is a major factor in determining population dynamics and biological control. We found that compared to soybean monoculture, the presence of soybean Glycine max L. (Fabales: Fabaceae) in the polyculture treatment reduced the population dynamics of the mirid predator but increased biological control. This result suggests that non-host crops in a polycultural succession could benefit from the natural enemy populations that were increased by other suitable crops in the succession. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum: Agronomy is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For agronomic, environmental, and economic reasons, the need for spatialized information about agricultural practices is expected to rapidly increase. In this context, we reviewed the literature on remote sensing for mapping cropping practices. The reviewed studies were grouped into three categories of practices: crop succession (crop rotation and fallowing), cropping pattern (single tree crop planting pattern, sequential cropping, and intercropping/agroforestry), and cropping techniques (irrigation, soil tillage, harvest and post-harvest practices, crop varieties, and agro-ecological infrastructures). We observed that the majority of the studies were exploratory investigations, tested on a local scale with a high dependence on ground data, and used only one type of remote sensing sensor. Furthermore, to be correctly implemented, most of the methods relied heavily on local knowledge on the management practices, the environment, and the biological material. These limitations point to future research directions, such as the use of land stratification, multi-sensor data combination, and expert knowledge-driven methods. Finally, the new spatial technologies, and particularly the Sentinel constellation, are expected to improve the monitoring of cropping practices in the challenging context of food security and better management of agro-environmental issues. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum: Agronomy is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Three strict field experiments (2010-2013) were conducted at the Experimental Station of Cultivar Testing in Chrząstowo in Poland (53°11′N, 17°35′E). Diagnosis of fungal pathogens to determine the threats posed by complex of diseases to two wheats, cv. Cytra (bread type) and cv. Monsun (quality type), was carried out. Risk assessment in the context of integrated pest and disease management considering crop sequence, sowing date, and control by fungicide application was carried out. This method also investigates the grain yields of wheat to address the context of disease risk with grain production. The experimental factors were fixed: pre-crop for wheat (sugar beet- B, corn for grain- C, wheat- W), the sowing date: facultative in late autumn ( F) and spring ( S), fungicidal intensification: C1-untreated, C2-one treatment at T2 stage (BBCH 32-65) with fluoxastrobin and prothioconazole, C3-two treatments made at T1 (BBCH 30-32) with prothioconazole and spiroxamine and at T2 (BBCH 41-65) with fluoxastrobin and prothioconazole, C4-three treatments performed at stage T1 (BBCH 29-31) with prothioconazole and spiroxamine, T2 (BBCH 37-51) with fluoxastrobin and prothioconazole, and T3 (BBCH 65-69) with prothioconazole and tebuconazole. A total of 12 wheat diseases were diagnosed, four units for foot and root rot and eight related with leaf and head. The most healthy status reached the crops of cv. 'Monsun': BFC4-C3, BSC4-C3, WSC4-C3, WFC4-C3, CFC4-C2 CSC4-C3, and for root and stem base: BSC4-C1, BFC4-C1, CSC4-C1, CFC4-C1. The lowest risk possessed by root and root rot diseases for cv. Cytra had crops: BFC4-C1, BSC3, CFC4-C3, and due to leaf and ear diseases the crops: BFC2-C4, BSC2-C4, WFC2-C4, WSC2-C4, CFC2-C4, CSC2-C4. Crop sequence was found the prime factor for risk posed by foot and root rot diseases, while the lack of fungicidal control mostly impacted the risk posed by leaf and head pathogens. The highest increases in yield from controlled crops were attributed to facultative wheat followed after beet (49-66 %) or wheat (36-47 %). Wheat responded positively to C2 program with a rise in yield of 26 % for cv. 'Monsun' and 21 % for cv. 'Cytra.' The cost-effectiveness based on two indicators E and Q has been calculated for fungicide treatments on all 48 crops. [ABSTRACT FROM AUTHOR]

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nematropica is the property of Organization of Nematologists of Tropical America and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Landscape spatial organization (LSO) strongly impacts many environmental issues. Modelling agricultural landscapes and describing meaningful landscape patterns are thus regarded as key-issues for designing sustainable landscapes. Agricultural landscapes are mostly designed by farmers. Their decisions dealing with crop choices and crop allocation to land can be generic and result in landscape regularities, which determine LSO. This paper comes within the emerging discipline called 'landscape agronomy', aiming at studying the organization of farming practices at the landscape scale. We here aim at articulating the farm and the landscape scales for landscape modelling. To do so, we develop an original approach consisting in the combination of two methods used separately so far: the identification of explicit farmer decision rules through on-farm surveys methods and the identification of landscape stochastic regularities through data-mining. We applied this approach to the Niort plain landscape in France. Results show that generic farmer decision rules dealing with sunflower or maize area and location within landscapes are consistent with spatiotemporal regularities identified at the landscape scale. It results in a segmentation of the landscape, based on both its spatial and temporal organization and partly explained by generic farmer decision rules. This consistency between results points out that the two modelling methods aid one another for land-use modelling at landscape scale and for understanding the driving forces of its spatial organization. Despite some remaining challenges, our study in landscape agronomy accounts for both spatial and temporal dimensions of crop allocation: it allows the drawing of new spatial patterns coherent with land-use dynamics at the landscape scale, which improves the links to the scale of ecological processes and therefore contributes to landscape ecology. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Agricultural Sciences / Revista Brasileira de Ciências Agrárias is the property of Universidade Federal Rural de Pernambuco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sorghum bicolor is an allelopathic crop that reduces the yield of succeeding crops. We have assessed its effect on the germination, emergence, and seedling growth of Arachis hypogea sown in soil that had had a prior sorghum cropping. A. hypogea was sown on rows and interrows of a previous sorghum crop in 1997 and 1998 in Senegal. Seedling establishment (germination rate and seedling weight) was better between rows than on rows of the previous crop. The highest concentrations of phenolic compounds occurred in the rows in 1998, while contents of row and interrow soils were similar in 1997. Vanillic acid was the main component of the six chemicals found in 1997 soils, whereas the 1998 soil samples contained mainly p-hydroxybenzoic acid, p-hydroxybenzaldehyde, vanillic, and p-coumaric acids (10 phenolics identified). The germination of peanut seeds in water (control), soil water extracts, and mixtures of pure phenolics (equivalent to those in 1997 and 1998 soil samples) was tested. All extracts inhibited germination compared to controls, but there was no significant difference among treatments, i.e., the inhibition was the same for seeds in soil solutions and those in the respective phenolic mixtures. Similarly, there were no significant differences among the germination rates in soil water extracts of rows and interrows or in the pure phenolic mixtures of rows and interrows. We propose a geometrical sowing pattern for peanuts between the rows of the previous sorghum crop to escape the latter's "allelopathic heritage." [ABSTRACT FROM AUTHOR]

Due to legume-based systems improving several aspects of soil fertility, the diversification of agrosystems using legumes in crop succession is gaining increasing interest. The benefits of legumes aroused the interest of farmers in the association of the Economic and Environmental Interest Group (EEIG), who introduced the idea of using the winter pea instead of rapeseed in their crop succession. The aim of this study is to evaluate the effects of the winter pea compared to those of rapeseed, as a head crop of the rotation, on soil microbial communities, enzyme activities, nitrogen (N) balance and yields. The field experiment involved two farmer plots that were selected within the EEIG. In each plot, two crop successions, including winter pea–wheat and rapeseed–wheat with fertilized and unfertilized strips, were examined for two years. Three times a year, under the wheat crop, composite soil samples were collected at depths of 0–20 cm, for microbial abundance and enzyme activity analyses, and twice a year at a depth of 0–60 cm, for the measuring of the mineral N. The results showed that the rapeseed–wheat succession maintained or enhanced soil bacterial and fungal biomasses and their enzyme activities. The winter pea–wheat succession enriched the soil's mineral N content more consistently than the rapeseed–wheat succession. The mineral N enhancement's effect was maintained under the wheat crop. Overall, the impact of the winter pea was positive on the soil's N dynamics, but wheat yields were equivalent regardless of the previous crop (winter pea or rapeseed with and without fertilization). In the Normandy region, as rapeseed requires a large amount of N fertilizer and pesticide to maintain the yield and quality of crop products, it is suitable to favor the introduction of the winter pea as the head crop of the rotation, which indirectly allows for a reduction in the costs of input production and use, the working time of farmers and environmental pollution. [ABSTRACT FROM AUTHOR]