Intercropping Systems: An Opportunity for Environment Conservation within Nut Production
Global population growth and intensive agriculture have both contributed negatively to the environment. As a result, there is increasing interest in the use of sustainable alternatives is increasing to promote better use of natural resources and create an equilibrium between agriculture and the environment. Intercropping, the simultaneous cultivation of multiple crops, aims to optimize land use economically while enhancing biodiversity through plant–microorganism interactions, thereby boosting crop productivity. This practice has particularly benefited nut production by combining the nutrient-sequestering capacity of trees with continuous annual crop production, improving soil nutrient and water utilization. Intercropping systems not only enhance nut yield and quality but also offer economic advantages to farmers. This review synthesized the existing literature with the aim of highlighting not only the positive aspects that intercropping brings to the production of nuts, but also the challenges and limitations faced in different regions when it comes to agricultural production. https://doi.org/10.3390/agriculture14071149
Exploring the bioactive potential of dried fruit by-products: a focus on hazelnut, peanut, and almond teguments and shells
Dried fruits are renowned for their nutritional value, particularly their seeds. However, their skins, shells, and hulls also hold significant nutritional and commercial potential, yet remain largely unexplored for their bioactive compounds. This study examines the teguments and shells of three types of dried fruits – hazelnut, peanut, and two almond varieties. Ethanol extracts from these by-products reveal a variety of phytochemicals with antioxidant, antimicrobial, anti-inflammatory, and antiviral properties, confirmed through in vitro and in vivo assays. Teguments contain higher polyphenol levels compared to shells, with 24 compounds identified via HPLC analysis. The Achak almond tegument extract demonstrates strong antiradical activity, significant antimicrobial effects, and notable antiviral properties at a low concentration. Moreover, extracts from Achak almond tegument and hazelnut shells exhibit notable anti-inflammatory properties. This underscores the potential of utilizing dried fruit by-products to create innovative, value-added products, supporting environmental sustainability and boosting the competitiveness of the dried fruit industry. https://doi.org/10.1080/09603123.2024.2373174
Insights into the cashew production system in Guinea-Bissau: implications for agroecosystem sustainability
Introduction: West Africa, particularly Guinea-Bissau, heavily relies on cashew nut (Anacardium occidentale L.) production, which significantly impacts the countries’ economies. Cashew exhibits remarkable adaptability to impoverished and arid soils. Understanding producers’ socio-economic characteristics is crucial due to their potential influence on crop productivity and household income. Methods: This study aims to characterize the socio-economic, productive, and phytosanitary aspects of cashew production in Guinea-Bissau, through 151 interviews with producers across all administrative regions of the country. Results: Our findings reveal that cashew producers are mainly males aged 40 to 60, they typically manage plantations under 5 ha, with the smaller plantation areas located in Gabú, Cacheu, and Bolama. The age of the older trees averaged 31 years, with the highest age found in Biombo. Tree density averaged 286 trees per hectare, with higher values in Cacheu, Bafatá, and Bolama. Cashew nut yield in 2020 averaged less than 0.5 tons per hectare, with farmer-set prices generally lower than government determined prices. Oio, Tombali, and Bolama were the regions most affected by pests, while Oio and Cacheu (North) were the most affected by diseases. Top pests included termites, branch girdler, weaver ants, African grasshopper, and stem borer; while top diseases comprised gummosis, anthracnose, and dieback. Discussion: Characterization of cashew production system is crucial at both national and regional levels to identify region-specific limitations and strengths, aiding in the formulation of tailored strategies for sustainable production. Moreover, cashew production plays a crucial role in household incomes in Guinea-Bissau, underscoring the necessity of developing integrated management strategies. https://doi.org/10.3389/fsufs.2024.1439820
Protocol: A Novel Approach to Assess Several Environmental Impacts of Diets on Differences of Nut Intake
Linking Conventional and Organic Rainfed Almond Cultivation to Nut Quality in a Marginal Growing Area (SE Spain)
The need to improve agroecosystem sustainability to secure yields, minimize environmental impacts and improve soil health is widely recognized. Organic production systems are one of the strategies that may be used to alleviate the negative environmental repercussions of conventional agriculture. In the present study, we compared the impact of conventional and organic production systems on the almond (Prunus dulcis (Mill.) D.A. Webb) yield and quality of nuts of two cultivars (Marcona and Desmayo largueta), with both systems being managed on marginal hillslopes in the southeast of Spain. Our findings show that the organic production system in rainfed almond trees has positive effects on certain nut quality parameters, with a slight decrease in almond yield, specifically 9.5% for cv. D. largueta and 1.3% for cv. Marcona, with respect to the conventional system. The results obtained have varied depending on the cultivar. Statistically significant differences have been obtained for cv. Marcona in the sugar content (54.4 and 49.8 g kg−1 in organic and conventional, respectively) and the total phenol content (3.41 and 2.46 g GAE kg−1 for organic and conventional, respectively). In the case of cv D. largueta, statistically significant differences were found between the organic and conventional systems for antioxidant activity (14.8 vs. 8.68 mmol Trolox kg−1, DPPH), fatty acid content (229 vs. 188 g kg−1 dw), saturated fatty acids (36 vs. 28.7 g kg−1 dw), monounsaturated fatty acids (113 vs. 110 g kg−1 dw) and polyunsaturated fatty acids (60.3 vs. 49.6 g kg−1 dw). Here, we show for the first time how a rainfed organic system allows for higherquality almonds, specifically with a higher content of phytochemicals beneficial for health, which, together with the higher price compared to conventional almonds, could compensate for the yield losses while preserving the sustainability of marginal agroecosystems.
Mitigation of salinity stress in ‘Chandler’ walnuts through the application of Ascophyllum nodosum extracts to soil: effects on growth, yield, and its impact on physical and biological soil properties
In Chile most of the walnut orchards are located in semiarid areas prone to saline conditions. Therefore, mitigating salinity stress is a relevant issue for farmers, especially for ‘Chandler’, the most sensitive planted variety. The aim of this study was to evaluate the effect of an extract of Ascophyllum nodosum (ANE; Acadian Organic®), applied through drip irrigation, on the vegetative and productive response of 'Chandler' walnut orchard affected by salinity (soil EC 1.8 dS m-1; irrigation water 2.0 dS m-1), effects on physical and biological soil properties. A dose of 4 L ha-1 ANE was applied monthly during two seasons (2021-2022 and 2022-2023) from the beginning of shoot growth until one month before harvest (24 L ha-1 per season), compared to unamended control. ANE applications promoted good conditions for tree development, greater shoot thickness, higher SPAD index measurements and better vegetative expression, represented by the NDVI spectral index. Consequently, a greater proportion of kernel filling and sizes was found in the ANE treatment (kernel size >32 mm, first season: 54% ANE vs 45% control; second season: 26% ANE vs 6% control). The stress mitigation of ANE promoted a positive cumulative effect after 1 season, with early vegetative development in the second season and significantly greater fruit size and yield efficiency. In addition, ANE application significantly improved physical and biological soil properties, possibly increased soil microbial activity, stimulated organic matter accumulation, improved the soil aggregate stability, and increased soil macroporosity at greater depths. The latter is relevant for salt management since a more stable soil porous system favors adequate water distribution in the soil profile under irrigation cycles, improving the displacement of salts and, consequently, reducing salinity stress. https://doi.org/10.1007/s10811-024-03277-z
Agronomic response, transpiration and water productivity of four almond production systems under different irrigation regimes
In recent years, more intensive production systems have been developed, coinciding with a growing scarcity of water resources. This context underscores the imperative of prioritizing water productivity (WP) as a critical factor in choosing the optimal production system to minimize agricultural water use. This study aims to contribute by evaluating WP in almond orchards under four production systems: open vase with severe pruning (open vase), open vase with minimal pruning (open vase (MP)), central axis and hedgerow. Three irrigation treatments were applied over two consecutive growing seasons: fully irrigated, mild stress and severe stress. Crop transpiration was monitored over the two years using both sap flow sensors and the two-source energy balance (TSEB) model with remote sensing. The severe stress treatment exhibited a notable reduction in kernel yield and nut load of 31.6 % and 34.5 %, respectively, in the second year of water deficit. The hedgerow system tended to have similar kernel yield to the open vase (MP) and central axis systems, and higher compared to the open vase system. Additionally, both transpiration measurement methods revealed that hedgerow exhibited lower transpiration rates across all irrigation treatments. Therefore, the highest WP was observed in the hedgerow system throughout both studied years. Similar findings were derived from the analysis of long-term data. Our findings indicate that the hedgerow production system had the highest WP, averaging 0.43 kg m−3 historically, compared to 0.33 kg m−3 for the open vase, 0.34 kg m−3 for the open vase (MP), and 0.36 kg m−3 for the central axis systems. https://doi.org/10.1016/j.scienta.2024.113335
Extraction of bioactive compounds from pecan nutshell: An added-value and low-cost alternative for an industrial waste
The pecan nutshell [Carya illinoinensis (Wangenh) C. Koch] (PNS) is a source of bioactives with important beneficial properties for the human health. PNS represents between 40-50 % of total mass of the nut, resulting as waste without any added value for the food industry. Even though a variety of methods were already developed for bioactive extraction from this waste, unconventional methodologies, or those which apart from green chemistry principles, were discarded considering the cost of production, the sustainable development goals of United Nations and the feasibility of real inclusion of the technology in the food chain. Then, to add-value to this waste, a low-cost, green and easy-scalable extraction methodology was developed based on the determination of seven relevant factors by means of a factorial design and a Response Surface Methodology, allowing the extraction of bioactives with antioxidant capacity. The pecan nutshell extract had a high concentration of phenolic compounds (166 mg gallic acid equivalents-GAE/g dry weight-dw), flavonoids (90 mg catechin equivalent-CE/g dw) and condensed tannins (189 mg CE/g dw) -related also to the polymeric color (74.6 %)-, with high antioxidant capacities of ABTS+. radical inhibition (3665 µmol Trolox Equivalent-TE/g dw) and of iron reduction (1305 µmol TE/g dw). Several compounds associated with these determinations were identified by HPLC-ESI-MS/MS, such as [Epi]catechin-[Epi]catechin-[Epi]gallocatechin, myricetin, dihydroquercetins, dimers A and B of protoanthocyanidins, ellagitannins and ellagic acid derivatives. Hence, through the methodology developed here, we obtained a phenolic rich extract with possible benefits for human health, and of high industrial scalability for this co-product transformation. https://doi.org/10.1016/j.foodchem.2024.139596
Green and sustainable use of macadamia nuts as support material in Pt-based direct methanol fuel cells
The successful commercialization of direct methanol fuel cells (DMFCs) is hindered by inadequate methanol oxidation activity and anode catalyst longevity. Efficient and cost-effective electrode materials are imperative in the widespread use of DMFCs. While Platinum (Pt) remains the primary component of anodic methanol oxidation reaction (MOR) electrocatalysts, its utilization alone in DMFC systems is limited due to carbon monoxide (CO) poisoning, instability, methanol crossover, and high cost. These limitations impede the economic feasibility of Pt as an electrocatalyst. Herein, we present the use of powdered activated carbon (PAC) and granular activated carbon (GAC), both sourced from macadamia nut shells (MNS), a type of biomass. These bio-based carbon materials are integrated into hybrid supports with reduced graphene oxide (rGO), aiming to enhance the performance and reduce the production cost of the Pt electrocatalyst. Electrochemical and physicochemical characterizations of the synthesized catalysts, including Pt-rGO/PAC-1:1, Pt-rGO/PAC-1:2, Pt-rGO/GAC-1:1, and Pt-rGO/GAC-1:2, were conducted. X-ray diffraction analysis revealed crystallite sizes ranging from 1.18 nm to 1.68 nm. High-resolution transmission electron microscopy (HRTEM) images with average particle sizes ranging from 1.91 nm to 2.72 nm demonstrated spherical dispersion of Pt nanoparticles with some agglomeration across all catalysts. The electrochemical active surface area (ECSA) was determined, with Pt-rGO/GAC-1:1 exhibiting the highest ECSA of 73.53 m2 g-1. Despite its high ECSA, Pt-rGO/GAC-1:1 displayed the lowest methanol oxidation reaction (MOR) current density, indicating active sites with poor catalytic efficiency. Pt-rGO/PAC-1:1 and Pt-rGO/PAC-1:2 exhibited the highest MOR current densities of 0.77 mA*cm-2 and 0.74 mA*cm-2, respectively. Moreover, Pt-rGO/PAC-1:2 and Pt-rGO/PAC-1:1 demonstrated superior electrocatalytic mass (specific) activities of 7.55 mA/mg (0.025 mA*cm-2) and 7.25 mA/mg (0.021 mA*cm-2), respectively. Chronoamperometry tests revealed Pt-rGO/PAC-1:2 and Pt-rGO/PAC-1:1 as the most stable catalysts. Additionally, they exhibited the lowest charge transfer resistances and highest MOR current densities after durability tests, highlighting their potential for DMFC applications. The synthesized Pt supported on PACs hybrids demonstrated remarkable catalytic performance, stability, and CO tolerance, highlighting their potential for enhancing DMFC efficiency. https://doi.org/10.1016/j.heliyon.2024.e29907
Predictive Neural Network Modeling for Almond Harvest Dust Control
This study introduces a neural network-based approach to predict dust emissions, specifically PM2.5 particles, during almond harvesting in California. Using a feedforward neural network (FNN), this research predicted PM2.5 emissions by analyzing key operational parameters of an advanced almond harvester. Preprocessing steps like outlier removal and normalization were employed to refine the dataset for training. The network's architecture was designed with two hidden layers and optimized using tanh activation and MSE loss functions through the Adam algorithm, striking a balance between model complexity and predictive accuracy. The model was trained on extensive field data from an almond pickup system, including variables like brush speed, angular velocity, and harvester forward speed. The results demonstrate a notable predictive accuracy of the FNN model, with a mean squared error (MSE) of 0.02 and a mean absolute error (MAE) of 0.01, indicating high precision in forecasting PM2.5 levels. By integrating machine learning with agricultural practices, this research provides a significant tool for environmental management in almond production, offering a method to reduce harmful emissions while maintaining operational efficiency. This model presents a solution for the almond industry and sets a precedent for applying predictive analytics in sustainable agriculture. https://doi.org/10.3390/s24072136