Cashew gum hydrogel as an alternative to minimize the effect of drought stress on soybean
The use of hydrogels helps the production of plants in drought-stress environments. Thus, this work evaluated using different hydrogels to minimize drought stress in soybean cultivation. The treatments employed two different hydrogels, one already commercialized and the other produced with cashew gum (Anacardium occidentale), five levels (0, 30, 60, 120, and 240 mg pot-1) of the hydrogels, and two levels of drought stress in sandy soil. The growth and yield of soybeans and the levels of macro- and micronutrients in soybeans were evaluated. The use of CG hydrogel promoted 12% increase in protein content in the seeds in the when soybean plants were subjected to drought stress. The levels of 30 mg pot-1, corresponding to 7.5 kg ha-1, improved the 'morphological and productive parameters of the soybeans. The increasing levels of hydrogel promoted the increase in P, K, Ca, Mg, and Fe and reduced S and Cu on an exponential scale. The use of cashew gum hydrogel increased the K and Ca contents in soybean seeds compared to commercial hydrogel.
https://doi.org/10.1038/s41598-024-52509-2
Advancements in peanut mechanization: Implications for sustainable agriculture
Context: Peanuts (Arachis hypogaea) hold significant global economic and nutritional importance, positioning them as a crucial crop in the realm of sustainable agriculture. In this comprehensive systematic and meta-analytic review, we thoroughly examine the extensive research and innovative strategies related to mechanizing peanut farming, with a specific focus on activities encompassing tilling, sowing, and harvesting. Objective: Our primary aim is to provide a meticulous and analytical exploration of the far-reaching implications of mechanization in peanut production. We emphasize the urgent need for cost-effective, socially responsible, and environmentally sustainable practices. Methods: Through a rigorous analysis of existing literature, we unveil the multifaceted impacts of mechanization on factors such as yield, quality, and losses in peanut cultivation. To ensure a comprehensive analysis, we primarily concentrated on peer-reviewed articles sourced from distinguished databases such as Scopus® and Web of Science™. Specifically, our review encompasses studies published between 1989 and 2022, covering a diverse collection of bibliographic resources. This range spans from the inception of the term “mechanizable peanut” to the most recent publications in these interdisciplinary databases. To refine our search, we developed research-specific search strings by combining relevant keywords, including “PEANUT”, “TILLAGE”, “SOWING”, “DIGGING”, “HARVESTING”, and/or “MATURITY”, along with appropriate Boolean operators. A team of reviewers meticulously evaluated the readability, consistency, and eligibility of papers by scrutinizing titles, highlights, abstracts, keywords, as well as materials and methods sections. We selectively included papers that aligned with our research scope, while excluding studies related to intercropping, rotation systems, fertilization, pests and diseases, and manual labor-related operations. Results and conclusions: Our findings highlight the potential for increased productivity and quality in agricultural systems that embrace mechanization, all while minimizing losses and their environmental impact. To optimize yield and quality while reducing losses, it is imperative for stakeholders to collaborate and endorse conservationist tillage practices, precision sowing techniques, and advanced harvesting methods. Significance: This meta-review serves as a call to action directed at the scientific community, policymakers, and producers, urging them to prioritize the integration of mechanization into peanut farming. This approach not only advances sustainable agricultural practices but also addresses the growing global demand for this essential crop. By examining advancements in conservationist tillage, precision sowing, and harvesting methodologies, we equip stakeholders with the knowledge required to enhance peanut cultivation. We particularly emphasize the importance of harnessing cutting-edge technologies, such as remote sensing for maturity prediction, to facilitate informed decision-making in the field.
https://doi.org/10.1016/j.agsy.2024.103868
Maize/peanut rotation intercropping improves ecosystem carbon budget and economic benefits in the dry farming regions of China
Monoculture is widely practiced to increase crop productivity, but long-term adaptation has drawbacks as it increases the depletion of soil nutrients and reduces soil quality, especially in dryland areas. Conversion from traditional maize monoculture to intercropping improves sustainable production. However, maize/peanut intercropping, especially rotation of planting strips impacts of maize/peanut intercropping in dryland on carbon (C) budgets and economic benefits remain unclear. In this study, a 5-year field experiment was conducted to evaluate the influence of maize/peanut intercropping with rotation of planting strips on soil health, indirect CO2-eq greenhouse gas emissions, and ecosystem C inputs. Four intercropping treatments viz. maize monoculture, peanut monoculture, maize/peanut intercropping, and maize/peanut rotation-intercropping were tested from 2018 to 2022. Maize/peanut rotation intercropping significantly improved the land equivalent ratio followed by intercropping and monoculture. Rotation-intercropping also improved economic benefits over intercropping and monoculture which were mainly associated with increased peanut yield where the border rows contributed the maximum, followed by the middle rows. Moreover, rotation-intercropping significantly increased the soil organic C and nitrogen (N) content. Rotation-intercropping decreased indirect CO2-eq greenhouse gas emissions and ecosystem C inputs by 3.11% and 18.04%, whereas increased ecosystem C outputs and net ecosystem C budget by 10.38% and 29.14%, respectively, over the average of monoculture. On average for intercropping and monoculture, rotation-intercropping increased ecosystem C emission efficiency for economic benefits by 51.94% and 227.27% in 2021 and 2022, respectively, showing the highest C utilization efficiency than other treatments. In the long run, maize/peanut rotation-intercropping can be practiced in dryland agriculture to achieve sustainable agriculture goals.
https://doi.org/10.1016/j.jenvman.2024.120090
A feasible re-use of an agro-industrial by-product: Hazelnut shells as high-mass bio-aggregate in boards for indoor applications
The present work investigates the feasibility of producing boards, with unconventional materials, namely hazelnut shells as a high-mass bio-aggregate and a sodium silicate solution as a no-toxic adhesive, and discusses possible applications based on an extensive characterization. The aim is to define a feasible reuse of a largely produced agro-industrial by-product to reduce the high environmental impact caused by both the construction and the agriculture sectors, by proposing a building composite that improves indoor comfort. The presented combination of aggregate-adhesive generated a product with characteristics interesting to explore. The thermal conductivity is moderated, and the composite achieved values of σmax = 0.39 N/mm² for flexural strength and σmax = 2.1 N/mm² for compressive strength, but it showed high sorption capacity with a moisture buffering value of about 3.45 g/(m² %RH), and a peak of sound absorption between 700 and 900 Hz. Therefore, the boards' most promising performance parameters seem to be their high hygroscopicity and acoustic absorption behaviour, namely in the frequency range of the human voice. Hence, the proposed composite could improve indoor comfort if applied as an internal coating board.
https://doi.org/10.1016/j.jclepro.2023.140297
Effects of Supplementary Pollination on Macadamia Nut Set, Retention and Yield in Murang’a County, Kenya
Macadamia is a promising prime dessert nut with the potential of alleviating poverty and enhancing food security in Kenya. Nut set and subsequent development of nuts to maturity is dependent on pollination which is mediated by animals, and honey bees are the dominant macadamia flower visitors. However, macadamia is pollen deficit as not all flowers set develop to mature nuts, thus supplemental pollination results to better nut yields. There is limited information in Kenya among the smallholder macadamia growers on the importance of supplementing pollination to enhance nut yields. This study was conducted at Kandara Macadamia Research Centre and in a smallholder macadamia farm located 15 km from the research centre, which was purposively selected from July 2021 to May 2023. Assessment of the influence of pollinators and supplementing pollination to nut set, retention and final yields was done. Honey bee, (Apis mellifera L.) colonies were also introduced at the Macadamia Research Centre to enhance pollination and mitigate deficits. Racemes were bagged to exclude pollinators, others left open to unlimited pollinator access while others received supplemental hand pollination. The results demonstrate that macadamia is pollen limited and pollination is highly reliant on insect pollinators. There were significant differences (p < 0.001) among the bagged (pollinator exclusion), open and hand pollinated racemes in both farms. The initial nut set and retention was increased significantly (21.54%) in hand pollinated racemes compared to those that were left to open pollination (unlimited pollinator visits) depicting pollination deficit in farm B. Introduction of supplementary honey bee colonies at the Kandara Macadamia Research Centre, resulted to higher nut set, retention, nut-in-shell and kernels. Macadamia growers are encouraged to introduce honey bee colonies in their farms to improve yields and also address pollination deficits. https://doi.org/10.5539/jas.v16n1p63
Land Suitability Assessment for Pistachio Cultivation Using GIS and Multi-Criteria Decision-Making: A Case Study of Mardin, Turkey
Site selection for pistachio orchards is an important issue for sustainable agricultural policies, crop productivity, agricultural planning, and communities. This study aims to investigate suitable places for pistachio in the Mardin Province (SE Turkey) by considering several variables, such as meteorological data, topographic conditions, economic factors, and soil characteristics, using Geographic Information System (GIS) and Multi-Criteria Decision Analysis. Pistachio farmers, expert opinions, and literature data were used to determine the requirements for pistachio cultivation. Four main assessment criteria (thirteen sub-criteria), sixty value ranges, and fourteen exclusion criteria were determined for the pistachio land suitability assessment. The weighting of the evaluation criteria was calculated using the Analytical Hierarchy Process (AHP). Farmers and experts have stated that meteorological factors are more important than soil, topography, and economic factors. All data were transferred to the GIS environment, and a land suitability map was created using the weighted linear combination method. The results show that Mardin province has very suitable lands for pistachio cultivation. The resulting map determined that the 228,891.59 ha area in Mardin province is very suitable for pistachio. To evaluate the accuracy of the land suitability map generated for pistachio, the Receiver Operating Characteristic (ROC) curve was used. The value of the area under the curve (AUC) was calculated to be 0.806, which indicates that the study is consistent. The created suitability map will be an essential data source for developing sustainable agricultural strategies in the Southeastern Anatolia region.
https://doi.org/10.1007/s10661-023-11899-y
Losing ground: projections of climate-driven bloom shifts and their implications for the future of California's almond orchards
Climate change is expected to impact the spring phenology of perennial trees, potentially altering the suitability of land for their cultivation. In this study, we investigate the effects of climate change on the bloom timing of almond orchards, focusing on California, the world's leading region for almond production. By analyzing historical climatic data, employing a model that considers hourly temperatures and fall non-structural carbohydrates to predict bloom dates, and examining various Coupled Model Intercomparison Project Phase 6 (CMIP6) scenarios, we assess the potential impacts of climate shifts on plant phenology and, consequently, on land suitability for almond farming. Our findings reveal that, within the next 30 years, the land suitable for almond production will not undergo significant changes. However, under unchanged emission scenarios, the available land to support almond orchard farming could decline between 48 to 73% by the end of the century. This reduction corresponds with an early shift in bloom time from the average Day of Year (DOY) 64 observed over the past 40 years to a projected earlier bloom between DOY 28-33 by 2100. These results emphasize the critical role climate shifts have in shaping future land use strategies for almond production in Central Valley, California. Consequently, understanding and addressing these factors is essential for the sustainable management and preservation of agricultural land, ensuring long-term food security and economic stability in the face of a rapidly changing climate. https://doi.org/10.1038/s41598-023-50688-y
Alternative fertilization practices lead to improvements in yield-scaled global warming potential in almond orchards
This study investigates the impact of alternative fertilization practices on the yield-scaled global warming potential (YS-GWP) in almond orchards. Almond production is a contributor to greenhouse gas emissions, primarily due to nitrogen-based mineral fertilizers. This research aims to identify strategies that reduce the environmental footprint of almond cultivation while maintaining yield. Field experiments were conducted in an almond orchard using three alternative fertigation practices: Advance Grower Practice (AGP), Pump and Fertilize (P&F), and High Frequency Low Concentration (HFLC). AGP is the current practice used by producers to meet annual N demand for almond tree growth; P&F is a reduction in applied N rate in response to measured N concentrations in the groundwater so that the added N and groundwater N reach the same total N applied; HFLC is a practice of applying smaller N rates per individual event. HFLC uses a greater number of fertigation events to reach similar total annual N load as other treatments. Cumulative N2O and CH4 emissions were used to determine GWP by converting the emissions to carbon dioxide equivalents (CO2eq) within a 100-year horizon. Nitrous oxide emissions were multiplied by a radiative forcing potential CO2eq of 298 and CH4 by 25 (UNFCCC, 2007). The results revealed that both P&F and HFLC reduced the YS-GWP compared to AGP. HFLC demonstrated 52–78% decrease in GWP per unit of almond yield compared to AGP, while P&F showed 48–58% decrease over AGP. These reductions were attributed to the reduced nitrous oxide emissions associated with P&F and HFLC. Further, P&F and HFLC tended to have higher N use efficiency than AGP. We demonstrate that adopting alternative fertilization practices can effectively mitigate the environmental footprint of almond orchards while maintaining crop yields. These practices offer viable options for almond growers to reduce greenhouse gas emissions, enhance sustainability, and contribute to climate change mitigation.
https://doi.org/10.1016/j.agee.2023.108857
Climate change impacts on insect pests for high value specialty crops in California
California is a global leader in production and supply of walnuts and almonds, and the state is the largest producer of peaches in the U.S. These crops have an important contribution to the California's agricultural economy. Damages to these crops from lepidopteran pests, mainly from Codling moth (Cydia pomonella) (family: Tortricidae), Peach twig borer (Anarsia lineatella) (family: Gelechiidae) and Oriental fruit moth (Grapholita molesta) (family: Tortricidae), are still high, despite the improvement in pest management activities. Given that temperature increase can directly impact the rate of growth and development of these pests, it is important to understand to what extent dynamics of these pests will change in future in California. The objective of this study was to quantify changes in the biofix, lifecycle length, and number of generations for these pests for the entire Central Valley of California. Using a well-established growing-degree days (GDD) model calibrated and validated using observations from orchards of California, and climate change projections from the Coupled Model Intercomparison Project phases 5 and 6 (CMIP5 and CMIP6) General Circulation Models, we found that biofix dates of these pests are expected to shift earlier by up to 28 days, and length of generations is expected to be shortened by up to 19 days, and up to 1.4 extra generations of these pests can be added by the end of the century depending on the scenario. Results from this work would enable industries to prioritize development of practices that are more effective in the long run, such as developing better cultural and biological pest solutions and insect tolerant varieties. Growers and researchers can take proactive actions to minimize future risks associated with these damaging pests. This work can be scalable to other pests and regions to understand regional dynamics of damaging agricultural pests under climate change. https://doi.org/10.1016/j.scitotenv.2023.167605
Production of high protein yeast using enzymatically liquefied almond hulls
Animal feed ingredients, especially those abundant in high quality protein, are the most expensive component of livestock production. Sustainable alternative feedstocks may be sourced from abundant, low value agricultural byproducts. California almond production generates nearly 3 Mtons of biomass per year with about 50% in the form of hulls. Almond hulls are a low-value byproduct currently used primarily for animal feed for dairy cattle. However, the protein and essential amino acid content are low, at ~30% d.b.. The purpose of this study was to improve the protein content and quality using yeast. To achieve this, the almond hulls were liquefied to liberate soluble and structural sugars. A multi-phase screening approach was used to identify yeasts that can consume a large proportion of the sugars in almond hulls while accumulating high concentrations of amino acids essential for livestock feed. Compositional analysis showed that almond hulls are rich in polygalacturonic acid (pectin) and soluble sucrose. A pectinase-assisted process was optimized to liquefy and release soluble sugars from almond hulls. The resulting almond hull slurry containing solubilized sugars was subsequently used to grow high-protein yeasts that could consume nutrients in almond hulls while accumulating high concentrations of high-quality protein rich in essential amino acids needed for livestock feed, yielding a process that would produce 72 mg protein/g almond hull. Further work is needed to achieve conversion of galacturonic acid to yeast cell biomass.
https://doi.org/10.1371/journal.pone.0293085