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There is a broad consensus that riparian buffers provide environmental benefits and increase resilience to climate change. In this study, we examined the potential benefits of multi-zone riparian buffers with outer layers planted in perennial crops (i.e., partially harvested buffers). This was accomplished by developing a simplified regional modeling tool, BioVEST, which was applied in the Mid-Atlantic region of the USA. Our analysis revealed that a substantial portion of variable costs to produce biomass for energy can potentially be offset by values provided by ecosystem services from partially harvested riparian buffers. Ecosystem services were monetized and found to represent a substantial fraction (median = ~42%) of variable crop production cost. Simulated water-quality improvements and carbon benefits generally occurred where buffer area was available, but hotspots occurred in different watersheds, suggesting potential trade-offs in decisions about buffer locations. A portion of buffers could be eligible for ecosystem service payments under US government incentive programs. Partially harvested buffers could represent a sustainable and climate-resilient part of multi-functional agricultural landscapes, and one that could become economically viable if farmers are able to reap the value of providing ecosystem services and if logistical challenges are resolved. Our results suggest that payments for ecosystem services can close the gap between what biorefineries are willing to pay and what landowners are willing to accept to grow and harvest perennials along streams., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Henriette Jager reports financial support was provided by US Department of Energy (DOE) Bioenergy Technologies Office (program manager Andrea Bailey) to Oak Ridge National Laboratory., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Perennial crops can deliver a wide range of ecosystem services compared to annual crops. Some of these benefits are achieved by lengthening the growing season, which increases the period of crop water and nutrient uptake, pointing to a potential role for perennial systems to mitigate soil nitrous oxide (N2 O) emissions. Employing a micrometeorological method, we tested this hypothesis in a 3-year field experiment with a perennial grass-legume mixture and an annual corn monoculture. Given that N2 O emissions are strongly dependent on the method of fertilizer application, two manure application options commonly used by farmers for each crop were studied: injection vs. broadcast application for the perennial; fall vs. spring application for the annual. Across the 3 years, lower N2 O emissions (P < 0.001) were measured for the perennial compared to the annual crop, even though annual N2 O emissions increased tenfold for the perennial after ploughing. The percentage of N2 O lost per unit of fertilizer applied was 3.7, 3.1 and 1.3 times higher for the annual for each consecutive year. Differences in soil organic matter due to the contrasting root systems of these crops are probably a major factor behind the N2 O reduction. We found that a specific manure management practice can lead to increases or reductions in annual N2 O emissions depending on environmental variables. The number of freeze-thaw cycles during winter and the amount of rainfall after fertilization in spring were key factors. Therefore, general manure management recommendations should be avoided because interannual weather variability has the potential to determine if a specific practice is beneficial or detrimental. The lower N2 O emissions of perennial crops deserve further research attention and must be considered in future land-use decisions. Increasing the proportion of perennial crops in agricultural landscapes may provide an overlooked opportunity to regulate N2 O emissions., (© 2015 John Wiley & Sons Ltd.)

Annual fiber sorghum (FS) and perennial giant reed (GR) cultivated in the Mediterranean area are interesting due to their high productivity under drought conditions and their potential use as lignocellulosic feedstock for biorefinery purposes. This study compares environmental constraints related to FS and GR produced on experimental farms (in the Campania region) using an attributional life cycle assessment (LCA) approach through appropriate modeling of the perennial cultivation. For both crops, primary data were available for agricultural management. Direct field emissions (DFEs) were computed, including the potential soil carbon storage (SCS). Giant reed showed the lowest burdens for all impact categories analyzed (most were in the range of 40%-80% of FS values). More apparent were the differences for climate change and freshwater eutrophication (respectively 80% and 81% lower for GR compared to FS). These results are due to the short-term SCS, experimentally detected in the perennial GR crop (about 0.25 ton C ha(-1) yr(-1), with a global warming offsetting potential of about 0.03 ton CO2/ton(GR dry biomass)). The results are also due to the annual application of triple superphosphate at the sowing fertilization phase for FS, which occurs differently than it does for GR. Phosphorous fertilization was performed only when crops were being established and therefore properly spread along the overall crop lifetime. For both crops, after normalization, terrestrial acidification and particulate matter formation were relevant impact categories, as a consequence of the NH3 DFE by volatilization after urea were spread superficially. Therefore, the results suggest higher environmental benefits of the perennial crop than the annual crop., (© 2015 SETAC.)

A network of agronomists, researchers, and practitioners associated with cacao farming provided open access to their independent field trials across Latin America and the Caribbean (LAC). A centralized dataset was assembled using qualitative and quantitative data from 25 experimental field trials (hereafter referred to as “CacaoFIT”) spanning several LAC agroecosystems. This dataset was used to document the main traits and agroclimatic attributes of the cacao cultivation model being tested within the CacaoFIT network. By synthesizing data from an entire network of cacao trials, this study aimed to highlight specific design features and management practices that may contribute to better cacao farming sustainability. The CacaoFIT network comprises 200 ha of field trials testing over 150 cacao genotypes and set up under dierent shade canopy design, management, and research goals. Small-sized trials were common across Mesoamerica, whereas medium to large-size trials were distinct to South America. Cacao trials were 15 years old (on average) and ranged from 3 to 25 years of establishment. Most cacao trials were managed conventionally (i.e., 55%), while 20% were under organic practices, and the remaining 25% presented both conventional and organic management approaches. Most field trials (ca. 60%) planted an average of 10 international clones or national cultivars at high (1,230–1,500 plants ha−1 ) and medium density (833–1,111 plants ha−1 ). Mixed shade canopies were the dominant agroforestry model, while timber vs. leguminous shade canopies were also common. The diversity and depth of research domains examined across the CacaoFIT network varied widely. Agronomy and agroforestry topics dominated the research agenda across all trials, followed by environmental services domains. Cacao physiology and financial performance were researched to a lesser extent within the network. Five featured field trials from CacaoFIT oered technical guidelines to inform cacao farming within similar contexts. This collaborative work is a scaold to encourage public–private partnerships, capacity building, and data sharing amongst cacao researchers across the tropic [ABSTRACT FROM AUTHOR]

Land degradation, climate change, soil and water contamination have led to increased interest in sustainable agricultural practices. Most agricultural practices are focused on growing annual crops, which require significant amounts of synthetic fertilizers, contribute to CO2 emissions and disrupt natural biological processes. Natural Systems Agriculture has been developed to reverse this paradigm by imitating nature through perennial grain crops. Kernza® intermediate wheatgrass (Thinopyrum Intermedium) is a promising perennial crop producing healthy grain for direct human consumption and forage for livestock while providing multiple ecosystemic services. Given these reasons, consider its cultivation in Argentina is relevant. This research aimed to predict Kernza crop suitability in the Azul district by modeling different climatic and soil densification scenarios. The model showed that Kernza can be grown in Azul, and that southern areas were most suitable. This model allowed generating information for land use planners and farmers to consider planting in Argentina, particularly, in Azul. Highlights: • Kernza can be grown in Azul district, especially in the deep, loamy soils of the southern areas. • The P50% precipitation scenario was found to be the most suitable for Kernza cultivation. • Considering different soil densification scenarios is crucial, as they affect water availability and water logging. • Kernza offers valuable ecosystem services and holds promise for land use planners and farmers in Azul and Argentina.

Pollinators are critical to ecosystem health and agricultural productivity. Endemic bee diversity and abundance among different crops has not been extensively studied, especially among perennial crops in Washington state. The goals of this study were to characterize bee genera diversity in south central Washington state, determine the abundance and diversity of bees among crop types, and determine if farming practices influence abundance and diversity by comparing bee diversity in managed agricultural sites to adjacent unmanaged, natural sites. This study investigated bee genera diversity and abundance in blueberry fields produced under organic certification programs, conventionally produced Concord juice and wine grape vineyards, conventionally produced spearmint and peppermint fields, and conventionally produced hopyards. The majority of bees found in the study were ground-nesting. Mint fields had the highest pollinator abundance and richness. In general, there was a greater abundance, diversity, and richness of bees found in unmanaged compared with managed sites. This indicates that areas of high agricultural intensity have relatively low bee genera abundance and diversity. [ABSTRACT FROM AUTHOR]

Intensive farming systems benefit from the additional ecosystem services provided by tree integration, which generate different growing conditions for the main crop. We studied yerba mate (Ilex paraguariensis) responses to growing conditions in monoculture (the conventional cropping system of yerba mate) and in three agroforestry systems: (1) yerba mate + Balfourodendron riedelianum ; (2) yerba mate + Peltophorum dubium ; and (3) yerba mate + Toona ciliata. Mainly, we focused on water relations and the hydraulic architecture of yerba mate. Agroforestry cropping systems provided a shade cover of around 34–45% and yielded as high as the conventional system. The shade cover influenced the allocation pattern to enhance leaf light capture, incrementing the leaf area to the sapwood area at the branch level. We also found a higher specific hydraulic conductivity in stems of yerba mate plants in consortium with T. ciliata than in the conventional cropping system, as well as higher resistance to water deficits due to lower vulnerability to embolism in the stems. During a severe drought, yerba mate plants had a similar stem and leaf water potential in both agricultural systems. Still, plants in monoculture had lower hydraulic safety margins and higher signs of leaf damage and mortality. This indicates that integrating trees into the yerba mate cultivation increases water stress resistance which would be beneficial to avoid restrictions on crop productivity under severe droughts induced by climate change. Plant resistance to drought is very important in the face of global warming that threatens agriculture. Integrating trees into Ilex paraguariensis cultivation provides additional ecosystem services and different growing conditions that the crop must acclimate. We found that plants in agroforestry systems are more resistant to water stress and have a greater safety margin than plants in monocultures, with similar yields. The incorporation of trees in this perennial crop can effectively be used to maintain productivity under water stress. [ABSTRACT FROM AUTHOR]

The agriculture sector can contribute to climate change mitigation by reducing its own greenhouse gas (GHG) emissions, sequestering carbon in vegetation and soils, and providing biomass to substitute for fossil fuels and other GHG‐intensive products. The sector also needs to address water, soil, and biodiversity impacts caused by historic and current practices. Emerging EU policies create incentives for cultivation of perennial plants that provide biomass along with environmental benefits. One such option, common in northern Europe, is to include grass in rotations with annual crops to provide biomass while remediating soil organic carbon (SOC) losses and other environmental impacts. Here, we apply a spatially explicit model on >81,000 sub‐watersheds in EU27 + UK (Europe) to explore the effects of widespread deployment of such systems. Based on current accumulated SOC losses in individual sub‐watersheds, the model identifies and quantifies suitable areas for increased grass cultivation and corresponding biomass‐ and protein supply, SOC sequestration, and reductions in nitrogen emissions to water as well as wind and water erosion. The model also provides information about possible flood mitigation. The results indicate a substantial climate mitigation potential, with combined annual GHG savings from soil‐carbon sequestration and displacement of natural gas with biogas from grass‐based biorefineries, equivalent to 13%–48% of current GHG emissions from agriculture in Europe. The environmental co‐benefits are also notable, in some cases exceeding the estimated mitigation needs. Yield increases for annual crops in modified rotations mitigate the displacement effect of increasing grass cultivation. If the grass is used as feedstock in lieu of annual crops, the displacement effect can even be negative, that is, a reduced need for annual crop production elsewhere. Incentivizing widespread deployment will require supportive policy measures as well as new uses of grass biomass, for example, as feedstock for green biorefineries producing protein concentrate, biofuels, and other bio‐based products. [ABSTRACT FROM AUTHOR]

The future of most tropical sectors is clouded by growing constraints linked to, among many other parameters, climate change, price volatility and labour scarcity. Perpetuating agricultural systems inherited from the colonial era (a time of abundant arable land, protected markets, and cheap and disciplined labour) will not be enough to prepare these sectors in facing immediate crucial challenges unless substantial structural transformations are made. Implementing a successful agroecological transition in a 70-billion USD sector, covering 25 million ha worldwide, calls for drastic changes in mind-sets and practices. The key issue is no longer simply to increase productivity, but to foster innovations designed to support endangered tropical biodiversity, while providing a decent living for shrinking agricultural communities in the Global South. Agroforestry practices have a role to play in providing substantial climate change mitigation with an impact comparable to other climate-focused solutions, such as reforestation. The expected contribution of oil palm-based agroforestry relies on agro-environmental services, as basic agricultural functions such as soil preservation, pollination, or pest control can be ensured by living organisms inside and around the plantation. Diversified systems are able to achieve both economic and environmental gains, as they use land more efficiently than monocultures. Building on regenerative agriculture, new plantation designs are emerging and deserve to be thoroughly assessed to establish evidence-based advocacy for change. [ABSTRACT FROM AUTHOR]

Aim of study: To analyse the diffusion of the crop by producing forecast models, that intend to help farmers in their decision-making. Area of study: Spain. The area dedicated to pistachio cultivation in Spain has multiplied by 36 in the period 2010 to 2020, reaching 44,244 ha. Material and methods: This study brings together data on the evolution of pistachio cultivation based on the following parameters: cultivated area, yield, and price. Methods are based on internal, external influence models and on an influence-price-crop yield pattern. Main results: The results indicate that given a constant crop yield, raising pistachio prices, will bring a production increase that generate the saturation level of the system. Similarly, with a constant pistachio price and an increment of the crop yield, the saturation level of the system increases. Regarding the pattern of influence, it is shown that in a context of suitable market prices for pistachio and an optimal synergy of the production factors that favour the crop yield not only increases the level of saturation of the system but also the duration of the diffusion process. Research highlights: The diffusion curve is sigmoidal with a well-defined inflection point and three well-defined phases. The adoption of pistachio in Spain responds to a model of internal influence (logistic) and never to models of external influence. According to the results, the process has a zero-innovation effect, while the dynamics of the process is completely determined by an imitation effect.

Considering the critical importance of insect pollination to food security and documented declines in wild bee populations, it is imperative to develop effective conservation and management strategies that promote the health of wild bee communities associated with agroecosystems. Identifying wild bee visitors of crops, including crop-flower visitors and species that nest within cropping areas, may prove critical to this endeavor as optimal conservation strategies may differ among bee species and/or guilds, regions, and cropping systems. Although lists of bee species that are associated with North American crops are scattered throughout the literature, there is a need for a comprehensive compilation of those species by crop, region, and nesting guild. Here, we searched the literature to compile a list of wild bee species associated with 33 major crops in North America and assessed the overlap in bee species communities among crops and regions. Of the 739 crop-associated bee species retrieved, 405 species (54.8%) were ground nesters, and 438 species (59.3%) were identified as crop-flower visitors of at least one crop. Because of their nesting and foraging behavior, we argue that these species are more likely to be exposed to agricultural pesticide residues than bee species that do not nest in the ground or feed directly on crop flowers. We further compiled lists of wild bees that have been found to be associated with all of the four most surveyed perennial fruit crops (apple, blueberry, cranberry, strawberry) and all of the three most surveyed cucurbit crops (cucumber, Cucurbita, watermelon) in eastern North America. These lists of bee species can be used to focus attention on species needing better protection strategies within agroecosystems, especially for these two important North American crop groups and can also inform the development of multi-species pesticide risk assessment schemes.

Given the massive and growing environmental impacts of conventional agriculture, humanity needs new methods for growing food that not only meet dietary needs but also provide for multiple ecosystem functions with potential benefits to people and biodiversity. Concepts from ecology and complex adaptive systems suggest that persistent structural heterogeneity and functional diversity are key for supporting biodiversity, ecosystem services, and resilience, but these concepts have not been extensively applied in agriculture, which is still dominated by annual monocropping systems. Perennial agriculture seems to embody these ecological concepts—particularly perennial polycultures that combine a variety of long‐lived woody perennial food crops with continuous ground cover. However, our understanding of the benefits and trade‐offs of such systems compared to conventional agriculture is limited, especially in temperate climates. Here, we provide a systematic and comprehensive study of the ecological attributes of 14 woody perennial polyculture farm fields to conventional annual and hay fields in the U.S. Midwest, one of the most industrialized food‐producing regions in the world. We found that perennial fields had (1) more diverse soil fungal, invertebrate, plant, and bird communities but found no difference in soil bacterial communities; (2) less compacted soil; (3) denser ground cover; (4) more active carbon, organic carbon, and nitrogen and the same available phosphorus in the top layer of soil; and (5) more species of predatory, detritivorous, and herbivorous insects, and approximately fourfold higher abundance of herbivorous insects. Food production from the oldest half of perennial fields was only 14.7% of a regional corn/soy rotation by weight, but increased with the age of the perennial field and had high nutritional diversity. Together, these findings indicate that woody perennial polyculture fields in the U.S. Midwest are characterized by higher biodiversity and ecosystem functions than adjacent conventional fields. Woody perennial polycultures in the temperate north might play a role in the transition of agricultural landscapes toward sustaining both people and nature over the long term. [ABSTRACT FROM AUTHOR]

Erosion and pollution in the Citarum River have reached a very worrying stage. To overcome this problem, the government has launched the Citarum Harum program. One of the policies synergistic with the Citarum Harum program is the application of soil and water conservation principles in farming seasonal crops in the upper Citarum watershed (UCW). Historically, policies and programs for developing pro-conservation farming in this area have been carried out for at least three decades but have not been effective. Increasing the effectiveness of policies requires the existence of suitable instruments. Therefore, it is necessary to have a comprehensive and in-depth understanding of the attitudes and behavior of farmers in applying soil and water conservation. This study aims to identify the factors influencing farmers’ probabilities and participation in applying soil and water conservation techniques. A double-hurdle approach is used to identify determinants of farmers’ participation and intensity in applying conservation practices. The data were collected from samples of 244 farm households’ growing seasonal crops out of 499 farm households sample in the Bandung and West Bandung Districts. The results show that the determinants of farmer participation and intensity in the application of conservation lie in the ability to finance, land tenure and utilization, and the physical condition of the land. The level of education only affects participation opportunities, even if the increment is significant. In the future, conservation priorities must be more directed at a vegetative approach through developing synergistic perennial crops with particular efforts to convert vegetables on the sloping lands to perennial crops.

Soil erosion is one of the biggest environmental problems throughout European Union causing considerable soil losses. Vegetation cover provides an important soil protection against runoff and soil erosion. To this aim, unlike annual crops, perennial plants have the advantage of covering soil for a longer time and reducing soil erodibility thanks to SOM increase due to litter effect and to reduction of soil disturbance (no-tillage). Two experiments were carried out in marginal hilly areas (10% slope) of Southern Italy: i) long-term experiment in which it was evaluated the effect of two fertilization doses (N: 100 and 50 kg N ha−1 from urea) on Arundo donax L. biomass production as well as its effect on soil erosion; ii) three-year experiment to evaluate the soil cover capacity of the giant reed by analysing the plant leaf area index (LAI). Results of the two experiments showed a good soil protection of Arundo donax L. that reduced soil losses by 78% as compared to fallow and showed soil erosion reduction not different from permanent meadow thanks to the soil covering during the period with the highest rain erosivity and to the reduction in soil erodibility. The protective effect of Arundo donax L. from rain erosivity was also confirmed by LAI analysis that showed a good soil covering of giant reed in the above mentioned period, even during the initial yield increasing phase following crop transplant. According to biomass yield, from the fifteen year of cultivation in a low fertile inland hilly area of Southern Italy, giant reed was characterized by a yield-decreasing phase that resulted postponed as compared to more fertile environments thus ensuring a longstanding soil protection from soil erosion. In addition, the higher nitrogen fertilization dose (100 kg ha−1 of N) allowed interesting biomass yield as compared to the lower dose (50 kg N ha−1) and kept constant SOC along the year of experimentation due to an improved contribution of leaf fall, root exudates and root turnover to soil. Highlights - Soil erosion is an important environmental problem in Mediterranean hilly areas. - Arundo donax L. can significantly reduce soil erosion in hilly cropland. - Soil protection of giant reed is high during the months with higher rain erosivity. - High N inputs enhance giant reed biomass production and soil fertility conservation. - In hilly areas yields are lower but more stable over time than in more fertile environments.

Perennial crops have been proposed as a solution to couple the production of sustainable biomass for multiple uses with several environmental benefits such as soil C storage. Concerns exist that the C sequestered in soil could be lost in a few years after the perennial crops are reverted to arable land. In this study, the current knowledge on the effects of perennial crop reversion on soil C and N was summarized by performing a meta-analysis. One year after the reversion a significant increase of soil C and N stocks (+15% and +12% respectively) were found in the 0–30 cm layer, while in the time interval between the second to fifth year after the reversion, there were no significant increases or decreases of soil C and N. The incorporation of the belowground biomass (BGB) into the soil at reversion plays a key role in the fate of soil C and N stocks after the reversion. In fact, when reverting a multiannual biomass crop there are significant losses of soil C and N. In contrast, when reverting a perennial biomass crop (PBCs) such as rhizomatous herbaceous or SRC woody crops there are no losses of soil C and N. The BGB of perennial grass is mainly composed of root systems and not of a huge amount of belowground organs as in the case of PBCs. The shredding of the BGB and its transformation as particulate organic matter (POM) represent the major pulse C input at the reversion that can undergo further stabilization into a mineral-associated organic matter (MAOM) fraction. Introducing PBCs into crop rotation resulted in an effective carbon farming solution with a potential positive legacy for food crops in terms of achievement of both climate and soil fertility goals.

Agricultural land in Europe is affected by low rooting depth (LRD) on 27.9 Mha. This marginal agricultural land can potentially be used to grow industrial crops without directly threatening food security or biodiversity conservation. However, little is known about the yield performance of industrial crops at LRD conditions. This study therefore compiles and discusses the meaningful data available in scientific literature. Twelve relevant industrial crops were identified for Europe. Currently, robust information on good growth suitability for LRD conditions is available for only one industrial crop, namely reed canary grass (RCG). Because this information was taken from field trial results from a single site, it remains unclear what role other growing conditions such as soil quality and climate play on both the yield level and the biomass quality of RCG under LRD conditions. These uncertainties about the quantitative as well as qualitative performance of industrial crop cultivation on marginal agricultural land characterized by LRD represent a major agronomic knowledge gap. Here, more knowledge needs to be compiled through both expanded crop science activities and improved international information exchange to make more optimal use of the large LRD areas available for the transition to a bioeconomy.

The cultivation of energy cane throughout the Southeastern United States may displace grazed pastures on organic soil (Histosols) to meet growing demands for biofuels. We combined results from a field experiment with a biogeochemical model to improve our understanding of how the conversion of pasture to energy cane during early crop establishment affected soil GHG (CO 2 , CH 4 , and N 2 O) exchange with the atmosphere. GHG fluxes were measured under both land uses during wet, hot and cool, dry times of year, and following a fertilization event. We also simulated the impact of changes in precipitation on GHG exchange. Higher fertilization of cane contributed to greater emission of N 2 O than pasture during warmer and wetter times of the year. The model predicted that energy cane emitted more nitrogen than pasture during simulated wetter than drier years. The modeled emission factor for N 2 O was 20 to 30-fold higher than the default value from IPCC (1%), suggesting that the default IPCC value could dramatically underestimate the consequences of this land conversion on the climate system. Predicted soil CH 4 and CO 2 fluxes were higher in pasture than energy cane, and this difference was not affected by increasing precipitation. Model simulations predicted that soils under first year cane emit more GHGs than pasture, particularly during wet years, but this difference disappeared two years after energy cane establishment. Our results suggest that management practices may be important in determining soil GHG emissions from energy cane on organic soils particularly during the first year of cane establishment. [ABSTRACT FROM AUTHOR]

Weed communities in irrigated orchards form spontaneous vegetative cover containing a remarkable presence of alien species. This plant cover can negatively affect the growth and productivity of orchards by reducing yield, but can also play a positive role by preventing soil erosion, increasing biodiversity and providing pollination services. Compositional and functional attributes of these weed communities are configured by management practices. Therefore, it is crucial to disentangle which differences in weed communities are mediated by management practices in order to establish management that promotes weed covers that enhance benefits while reducing negative effects on the orchards. In irrigated orchards of the Mediterranean area, management is dominated by irrigation (flood/drip) and weed control (mechanical/chemical). To identify how differences in irrigation and weed control modify weed communities in orchards, floristic surveys were carried out in mowed and herbicide-treated plots on drip and flood irrigated orchards. Weed community structure was evaluated in terms of species cover, diversity and the prominence of alien species for each management regime from a floristic and a functional approach. Results showed that irrigation system is the main factor influencing weed community structure. Compared to drip, flood irrigation is associated with a denser weed community with higher presence of alien weeds. Similarly, environmental conditions created by irrigation determine taxonomical and functional composition of weed communities and modulate the effect of weed control methods Flooding favours alien species, C 4 , perennial grasses, clonal species, zoochorous and hydrochorous and wind-pollinated species, whereas drip irrigation selects mostly native C 3 forbs, non-clonal, wind-dispersed and insect pollinated species. Therefore, this study provides insights into how modernizing irrigation method from a flood to a drip system can promote vegetative cover that maximizes benefits to the orchards and the environment while minimizing negative effects of the weeds and prominence of alien species within the weed community. [ABSTRACT FROM AUTHOR]

Perennial grains have been proposed to stabilise fragile lands while contributing grain and grazing in mixed farming systems. Genotype by environment (GxE) interactions for grain yield were investigated in 22 perennial rice ( Oryza sativa L./ Oryza longistaminata ) derivatives over four successive growing seasons at three sites in Yunnan in southern China and one site in Lao PDR. The GxE interaction accounted for 25.7% of the total sum of squares, with environment and genotype responsible for 57.4% and 16.9%, respectively. Cluster analysis identified seven environment and six genotype groups, which accounted for 55.6% of the GxE sum of squares. Principal component axes 1, 2 and 3 accounted for 42.3%, 19.1% and 16.5% of the GxE-SS, respectively, with PCA1 indicating yield potential, PCA2 delay in phenology under environmental stress, and PCA3 ratoon percentage. Environment groups differed in mean temperature, whether dry season or wet season, and occurrence of environmental stresses, such as periods of low minimum temperature or periods of rainfall deficit. Genotype groups differed in adaptation to these diverse environments. For genotype groups, G5 (PR23) was highest-yielding and broadly adapted across environments, while G1 (line 188, both 137s, both 139s, both 147s) was low-yielding and poorly adapted. Other genotype groups showed preferential adaptation: G3 (lines 60, 251, 264, Bt69, Bt71) to Simao/Dry Season (E3 and E4), G4 (lines 75, 243, 246, 249, 255) to Menglian/Wet Season (E1 and E2), G2 (line TZ) to Jing Hong 2013 (E7), and G6 (lines 56, 59, 214) to Jing Hong 2102 and Na Pok (E6 and E5). The results imply that regrowth success and maintenance of spikelet fertility over regrowth cycles are important for adaptation of perennial rice, especially to low minimum temperature at higher altitude and rainfall deficit at lower altitude, and future breeding programmes in perennial rice should address these environmental stresses. The high yield and broad adaptation of PR23 (G5) over environments makes it a prime candidate for release to stabilise fragile lands in the humid and subhumid tropics, while contributing grain and forage in mixed-farming systems. [ABSTRACT FROM AUTHOR]

Behaviour of crops and soils due to non-redressal of spatial variability in soil properties is not expressed uniformly within bigger orchard/field which has been the major triggering factor for not able to break yield barrier through conventional nutrient management strategy. Better response of site specific nutrient management (SSNM) over recommended doses of fertilizers (RDF) including those of farmers’ usual fertilizer practices (FFP) signals a wake-up call to address the fertilizer requirements on the principles of SSNM, if the full potential productivity of perennial crops has to be realized and sustain on any given soil type. The SSNM also warrants to tailor the fertilizer application on the basis of spatial variation in soil fertility and tree canopy size within an orchard/field through variable rate fertilizer application to minimize the gap between actual and potential productivity of crops. Application of geospatial tools like GPS and GIS coupled with DRIS- based nutrient diagnostics has substantially aided in developing rationale of fertilizer use using SSNM concept in crops like citrus, avocado, coconut, olive etc. which could well be expanded to other perennial crops.

Understanding how weed communities assemble as a function of biotic and abiotic filters and transform through time has important implications for the sustainable management of agronomic systems. In a three-year study, we evaluated weed community responses to lucerne (Medicago sativa, perennial) vs. continuous spring wheat (Triticum aestivum, annual, CSW) and weed management practices where weeds in the CSW system were managed with three contrasting approaches (herbicide, tillage or sheep grazing). Our results indicated no differences in weed diversity between the perennial and annual crops or across the different management practices in CSW. However, there were differences in weed community composition. Lucerne, with the exception of the establishing year, impeded the growth and reproduction of several annual weeds, including Amaranthus retroflexus, Thlaspi arvense, Lamium amplexicaule and Chenopodium album, but favoured perennial broad-leaved weeds such as Taraxacum officinale and Cirsium arvense. The replacement of herbicide treatments in pre-plant and post-harvest in CSW with soil tillage or sheep grazing selected for different weed communities beyond the second year of establishment. The weed species driving the differences in CSW systems were Androsace occidentalis, more common in CSW managed chemically; Asperugo procumbens, more common in CSW managed with tillage; and T. officinale and Lactuca serriola, more common in CSW managed with sheep grazing. Understanding how cropping systems modify weed communities is a necessary step to shift from reactive weed control programmes to predictive management strategies. [ABSTRACT FROM AUTHOR]

Abstract: In annual crops, where disturbance intensities are generally high, numerous investigations demonstrated beneficial effects of organic and other extensive farming practices on biodiversity. It is however unclear if organic farming has the same beneficial effect in perennial crops (e.g. vineyards) because of a generally reduced background disturbance level. Moreover, the impact of farming practices on biodiversity may differ between trophic levels. We tested the effect of farming practices differing in disturbance intensity on the abundance, species richness and community composition of three trophic levels (plants, grasshoppers and spiders) in Swiss vineyards. Organic and conventional vineyards were compared, and within the latter different options of weed control (mowing vs. mulching) and pest management (hand spraying vs. helicopter spraying) were investigated. In contrast to findings in annual crops, organic farming promoted neither diversity nor abundance at any trophic level. Grasshopper diversity was even significantly lower in organic compared to conventional vineyards. Weed control as well as pest management differed in their effects, depending on the trophic level. Within conventionally managed vineyards, spider and grasshopper diversity were enhanced by mulching, while plants benefited from the lower disturbance of mowing. The greater disturbance of fungicide spraying by hand than by helicopter was disadvantageous for grasshoppers, but did not affect spiders and plants. Thus, different taxa respond differently not only to an increase in disturbance but also to different types of disturbance and local site conditions. We conclude that disturbance in organically farmed vineyards appears to be too low to be beneficial for biodiversity. [Copyright &y& Elsevier]

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Abstract: Low-input and organic farming systems have notable differences in nitrogen (N) sources, cycling and management strategies compared to conventional systems with high inputs of synthetic N fertilizer. In low-input and organic systems, there is greater reliance on complex rotations including annual and perennial crops, organic N sources, and internal N cycling that more closely mimic natural systems. These differences in farming system practices fundamentally affect N availability and N use efficiency (NUE) and could impact crop traits and breeding strategies required to optimize NUE. We assess genetic and environmental factors that could assist breeders in improving crop performance in low-input and organic farming systems by examining NUE in natural and agricultural ecosystems. Crop plants have often been bred for high N productivity, while plants adapted to low N ecosystems often have lower productivity and higher levels of internal N conservation. Breeders can potentially combine N productivity and N conservation through the use of elite and wild germplasm. Beneficial genetic traits include the ability to maintain photosynthesis and N uptake under N stress and the ability to extract soil N at low concentrations, perhaps through beneficial associations with soil microorganisms. In addition, breeding for specific adaptation to climactic and management practices so that crop uptake patterns match N availability patterns, while minimizing pathways of N loss, will be critical to improving NUE. [Copyright &y& Elsevier]