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The olive tree holds great cultural, environmental, and economic significance in the Mediterranean region. In particular, Morocco has been making dedicated investments over $10 billion since 2008 to fuel the transition from cereal to olive production. Understanding the spatial extent of this large-scale land conversion is critical for a variety of socioeconomic purposes. In response to this demand, we conducted a study to map individual olive trees in northern Morocco using satellite imagery and deep learning techniques at a sub-national scale. This study utilized cloud-free, very-high-resolution DigitalGlobe imagery collected between 2018 and 2022 to identify each individual olive tree in six northern Morocco provinces. We compared various deep learning models, including both transformer-based and CNN-based models, to generate patch-level spatial constraints and pixel-level tree identification. We found that transformer-based models outperformed CNN-based models in both tasks. Additionally, spatially constraining the pixel-level results improved olive tree mapping accuracy to varying degrees, depending on the initial performance of the model. The evaluation of the olive map generated from this study shows high accuracy in both surveyed and unsampled regions. This research represents the first-of-its-kind individual olive tree mapping at the sub-national scale that can help monitor the large-scale land conversions such as about 110,000 ha of olive plantings in the six Moroccan provinces studies here. Meanwhile it demonstrates a cost-effective and efficient prototype approach that can be adapted to identify similar tree crop expansion occurring in other parts of the world. [ABSTRACT FROM AUTHOR]

Agroforestry is a widely proposed solution for climate change adaptation and resilience in agriculture due to the multiplicity of socio-ecological benefits. However, agroforestry as a practice exists on a dynamic scale of ecological complexity, which may cause different management regimes to respond distinctively to climate change. Due to the limited literature on climate change impacts on agroforestry in the temperate region, this paper reviews disturbance regimes and the observed and predicted responses of forests and farms using the US Northeast as an example. We also reference scholarship from tropical regions, where agroforestry adoption/study is more advanced, to enhance understanding of the growing field of agroforestry in temperate systems. We view transitions to and from agroforestry from a complex systems lens by identifying the disturbance, complexity, resilience, and adaptive capacity of systems to drive and respond to rapid change via human management, focusing on invasive species, phenological changes and range shifts in plants, pests, and pathogens of agroforestry systems. Management considerations including structural diversity, species selection and the intentional/non-intentional incorporation of introduced species can promote community ecological resilience to build systems that have adaptive capacity to withstand changing conditions. [ABSTRACT FROM AUTHOR]

Based on the need to protect previous ancient trees and the development of dendroclimatology, the use of non-destructive technologies in tree-ring research has gained increasing attention. This study focuses on the ancient Pinus tabulaeformis in Yu Xiang Forest Farm in Henan Province. Firstly, samples were collected using the traditional Increment borers and the Resistograph, a non-destructive method. Subsequently, the peak-valley analysis was used to filter the data obtained by the Resistograph to extract the tree ring width sequence, and the data's accuracy was verified by correlation analysis with tree ring width sequence by the Increment borers. Then, the optimal filtering method and an appropriate comprehensive threshold were determined, and tree ring width and density sequences were successfully extracted. Following that, the growth trend and residual resistance in the measurement process were corrected using linear fitting and Ensemble Empirical Mode Decomposition (EEMD) technology, thereby establishing the tree-ring width and density index series, which were further validated through correlation analysis and t-tests. Finally, analysis of the correlation with climatic factors, identified the main limiting factors for tree growth, and the accuracy of the tree-ring information extracted by the Resistograph was further verified. The results showed that spite of certain differences between the tree-ring width indices extracted by the Resistograph and the Increment borer, they were generally reliable. The radial growth of the ancient P. tabulaeformis in Yu Xiang Forest Farm is primarily influenced by temperature, with the maximum density of the tree rings responding more significantly to the mean maximum temperature, while the minimum density of the tree rings responded more significantly to the mean minimum temperature. These results not only provide a scientific and accurate age for the protection of ancient trees and verify the reliability of the data obtained by the Resistograph, but also facilitate the use of non-destructive technology for in-depth study of ancient trees, therefore enhancing our understanding of how climate change affects tree growth and provide valuable insights for the future protection and management of these ancient trees. [ABSTRACT FROM AUTHOR]

ABSTRACT Xylosandrus crassiusculus (Motschulsky) and Xylosandrus germanus (Blandford) (Coleoptera: Curculionidae: Scolytinae) are major ambrosia beetle pests in tree nut and fruit orchards and ornamental nurseries in the eastern United States (USA). Ethanol‐baited bottle traps and ethanol‐infused tree stem sections (i.e., bolts) have been used to monitor ambrosia beetles, but limited studies exist on the influence of ethanol‐lure release rate on ambrosia beetle trap captures and bolt attacks. We designed this study to compare low‐release (LR) and high‐release (HR) ethanol lures in bottle traps for capturing invasive ambrosia beetles. We also compared beetle attacks among bolts pre‐soaked in ethanol solutions of low (10%) and high (90%) concentrations and bolts cored and filled with the same low and high ethanol concentrations. In 2022, experiments were conducted in ornamental nurseries and apple, peach, or pecan orchards in five USA states. Higher numbers of X. crassiusculus and X. germanus were captured in bottle traps baited with the HR ethanol lure compared to the LR lure at most of the study sites. More attacks per bolt by X. crassiusculus and X. germanus were observed at most sites on pre‐soaked and filled bolts with 90% compared to 10% solutions of ethanol. Bolts soaked in low (10%) ethanol solutions sustained more attacks from both X. crassiusculus and X. germanus than cored bolts filled with low ethanol. These results will assist with monitoring the flight activity of invasive ambrosia beetles within nut, fruit, and ornamental tree crops. [ABSTRACT FROM AUTHOR]

Agroforestry, often promoted as a sustainable agriculture practice, is rapidly expanding, often at the cost of primary tropical forests. While agroforestry negatively impacts amphibian diversity, its effects on population demography, microhabitat, use and body condition are relatively understudied. This information is crucial for determining and promoting amphibian‐friendly land‐use practices. We compared habitats, population densities, microhabitat use and body condition of two endemic species of shrub frogs (Pseudophilautus amboli and Raorchestes bombayensis) across (1) elevations (low‐ and high‐elevation forests) and (2) land‐use categories (cashew, rubber and low‐elevation forests) in the northern part of the Western Ghats Biodiversity Hotspot. Using distance sampling, we demonstrated that the abundances of the two shrub frog species differed across elevation categories, with P. amboli more common in low‐elevation forests and R. bombayensis more prevalent in high‐elevation forests. Both species of frogs exhibited extremely skewed, male‐biased sex ratios, with three females for 100 males. P. amboli had lower densities and poor recruitment and exhibited altered microhabitat use in cashew plantations compared to low‐elevation forests. Although adult male P. amboli densities in rubber were similar to those in low‐elevation forests, they exhibited altered microhabitat use and smaller body sizes than in forests, indicating poor body condition. We demonstrate the differential impacts of agroforestry types on shrub frogs. We also demonstrate that distance sampling can be a useful tool for population monitoring of shrub frogs, which comprise almost 25% of the anuran diversity in the Western Ghats. There is a need to identify the drivers of extremely skewed sex ratios, which make these species vulnerable to population crashes. Given the recent downlisting of the two focal species to Least Concern, we advocate for their uplisting to at least Near Threatened status considering their patchy distribution, negative impacts of rapidly expanding agroforestry plantations and extremely skewed sex ratios. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET) is an important component of surface energy balance and a key process of hydrological cycle. Continuous and accurate estimation of regional ET is meaningful for water management, agricultural production, and climate change adaptation. Remote sensing (RS) technique is of important meaning for estimating ET on regional scale. In this study, a new method is developed to integrate the RS information and meteorological data based on the decouple model which is deduced from Penman–Monteith (PM) model. Firstly, a parameterization method for decoupling factor (Ω) which is key parameter in the decouple model and could reflect the coupling relationship between the land surface and atmosphere systems is introduced. Subsequently, the decouple model is applied to inverse regional ET in Beijing City and nearby region, from 1st, May, 2013 to 31th, October, 2020. Thirdly, the inversed daily ET values are evaluated based on the measured data at Huailai station and in Badaling Forest Farm. The results show that the changing trend of estimated ET and measured ET are basically the similar. The bias value is −0.12 mm d−1, the RSME value is 0.66 mm d−1, and the correlation coefficient is 0.52. Finally, the spatiotemporal trend of water consumption in study area is analysed based on the ET estimation results. The month with the largest water consumption in 2013 is July with the quantity of 0.92 billion m3, accounting for about 22% of the regional total water consumption in growing season. The regions with high ET values agree well with the regions of high soil moisture and high air humidity as well as high biomass. These results suggest that the decouple model is with great potential to generate regional daily ET products and to support irrigation management. [ABSTRACT FROM AUTHOR]

Carbohydrate levels are important regulators of the growth and yield of tree crops. Current methods for measuring foliar carbohydrate concentrations are time consuming and laborious, but rapid imaging technologies have emerged with the potential to improve the effectiveness of tree nutrient management. Carbohydrate concentrations were predicted using hyperspectral imaging (400–1000 nm) of leaves of the evergreen tree crops, avocado, and macadamia. Models were developed using partial least squares regression (PLSR) and artificial neural network (ANN) algorithms to predict carbohydrate concentrations. PLSR models had R2 values of 0.51, 0.82, 0.86, and 0.85, and ANN models had R2 values of 0.83, 0.83, 0.78, and 0.86, in predicting starch, sucrose, glucose, and fructose concentrations, respectively, in avocado leaves. PLSR models had R2 values of 0.60, 0.64, 0.91, and 0.95, and ANN models had R2 values of 0.67, 0.82, 0.98, and 0.98, in predicting the same concentrations, respectively, in macadamia leaves. ANN only outperformed PLSR when predicting starch concentrations in avocado leaves and sucrose concentrations in macadamia leaves. Performance differences were possibly associated with nonlinear relationships between carbohydrate concentrations and reflectance values. This study demonstrates that PLSR and ANN models perform well in predicting carbohydrate concentrations in evergreen tree-crop leaves. [ABSTRACT FROM AUTHOR]

Site selection analysis is a fundamental methodology for the regeneration of Xylella fastidiosa subsp. pauca (Xfp) infected areas, with the introduction of Xfp immune/resistant tree crop species. The diffusion of these species could be assessed by combining ecological optima data, climate and soil attributes of the study area, and GIS tools. The study aimed to evaluate the potential suitability of eight Xfp immune tree crops, including Neglected and Underutilized Species (NUS) drought-resistant and new species, as follows: carob, hawthorn, prickly pear, mulberry, loquat, walnut, persimmon, and avocado. The use of GIS tools allowed the integration of different layers, such as climate and soil, to contribute to the identification of suitable areas for the cultivation of these tree crops helping the policy-makers to define plans for land use at a regional scale. Following the ecological optima, which represents the ideal environmental conditions for each species, this analysis provided valuable insights into the compatibility of the selected tree crops with the prevailing environmental factors in the affected area. Carob revealed its remarkable adaptability and drought resistance, presenting the broadest suitability. Hawthorn and Loquat also exhibited high adaptability, indicating their potential contribution to agricultural diversification and ecological balance. Conversely, crops like Avocado, Prickly pear, and Walnut, despite their economic value, demonstrated limited adaptability due to their specific soil and climate requirements. These findings can potentially contribute to the development of strategies for the policymakers, aimed at diversifying and enhancing the resilience of agricultural systems, facing the problem of emerging quarantine pathogens and the incoming climate change, and highlighting the possibility of opening new cultivation scenarios in the zones affected by Xfp. [ABSTRACT FROM AUTHOR]

Background: Dissection of complex plant cell wall structures demands a sensitive and quantitative method. FTIR is used regularly as a screening method to identify specific linkages in cell walls. However, quantification and assigning spectral bands to particular cell wall components is still a major challenge, specifically in crop species. In this study, we addressed these challenges using ATR-FTIR spectroscopy as it is a high throughput, cost-effective and non-destructive approach to understand the plant cell wall composition. This method was validated by analysing different varieties of mungbean which is one of the most important legume crops grown widely in Asia. Results: Using standards and extraction of a specific component of cell wall components, we assigned 1050–1060 cm−1 and 1390–1420 cm−1 wavenumbers that can be widely used to quantify cellulose and lignin, respectively, in Arabidopsis, Populus, rice and mungbean. Also, using KBr as a diluent, we established a method that can relatively quantify the cellulose and lignin composition among different tissue types of the above species. We further used this method to quantify cellulose and lignin in field-grown mungbean genotypes. The ATR-FTIR-based study revealed the cellulose content variation ranges from 27.9% to 52.3%, and the lignin content variation ranges from 13.7% to 31.6% in mungbean genotypes. Conclusion: Multivariate analysis of FT-IR data revealed differences in total cell wall (600–2000 cm−1), cellulose (1000–1100 cm−1) and lignin (1390–1420 cm−1) among leaf and stem of four plant species. Overall, our data suggested that ATR-FTIR can be used for the relative quantification of lignin and cellulose in different plant species. This method was successfully applied for rapid screening of cell wall composition in mungbean stem, and similarly, it can be used for screening other crops or tree species. [ABSTRACT FROM AUTHOR]

Crop load regulation is vital for achieving excellence in orchards, particularly in terms of consistent yields and high-quality fruit. It also has a direct impact on tree nutrition. The objective of this study was to investigate the relationship between crop load and tree nutrition using segment linear regression models. The focus was on identifying any breakpoints in this relationship and exploring the connection between leaf nutrient contents and fruit quality characteristics. Additionally, the study aimed to determine the critical crop load level that influences biennial bearing. The research was conducted in a high-density 'Golden Delicious'/M.9 apple orchard located in the Lake Region of Turkey over three consecutive years (2013-2015). Twenty-four different crop load levels were examined to assess the impact of the number of fruits on leaf nutrient contents. The critical threshold levels were determined as follows: potassium [0.91 kg cm-2 Trunk Cross-Sectional Area (TCSA)], phosphorus (0.96 kg cm-2 TCSA), magnesium (0.97 kg cm-2 TCSA), manganese (0.99 kg cm-2 TCSA), zinc (1.0 kg cm-2 TCSA), and iron (1.15 kg cm-2 TCSA). This suggests that a crop load ranging from 3.71 to 4.69 fruit/cm² TCSA could be considered critical depending on the specific nutrient in tree nutrition. The results revealed significant negative correlations between leaf mineral contents and overall fruit quality characteristics. Moreover, the critical crop load threshold for biennial bearing (0.77 kg cm-2 TCSA) was found to be lower than the nutrient threshold. Building on previous studies, this research significantly contributes by clarifying the critical crop load level at which a sudden change occurs in macro- and micro-nutrients, as well as biennial bearing. [ABSTRACT FROM AUTHOR]

Tree–crop interaction studies help to determine the effects of trees on the production and yield of agricultural crops and could help indecisions on suitable crops and tree combinations to increase the overall production from agroforestry systems. Different varieties of agricultural crops might show different responses against the phytotoxic effects of Bauhinia species. This study was conducted to observe the phytotoxicity of two Bauhinia spp., i.e., Bauhinia retusa and Bauhinia variegata, on some Triticum aestivum varieties, i.e., VL-892, VI-829, VL-616, UP-2572, and UP-1109.The leaves and bark of these two species were harvested from the natural population for these experiments. On average, germination and radicle and plumule length of wheat varieties were significantly (p > 0.05) reduced by the leaf and bark extracts of both Bauhinia species. The effect of leaf and bark extracts of both Bauhinia species on seed germination percent of different wheat varieties revealed that the bark and leaf extracts showed maximum toxicity for germination percentage, and minimum influence was observed in radicle and plumule length. However, bark extracts were more toxic as compared to leaf extracts. Under leaf and bark extract concentrations, the VL 829 wheat variety showed stimulatory effects in germination and radicle and plumule growth under both Bauhinia species. On average, radicle and plumule growth of the test crop was increased with an increasing concentration of leaf and bark extract of B. variegata up to 50%, and thereafter, a decrease in radicle and plumule length was recorded. The VL 829 and UP 1109 varieties showed the lowest allelopathic effects and could be grown under both Bauhinia species with minimum yield loss. [ABSTRACT FROM AUTHOR]

In order to understand the non-structural carbon (NSC) content, nitrogen (N) phosphorus (P) potassium (K) ecological stoichiometric characteristics and their responses to tending thinning in different age stages of Populus×xiaohei, and to provide a basis for scientific management of Populus×xiaohei, the young and middle Populus×xiaohei plantation in Hongqi Forest Farm of Daqing City, Heilongjiang Provinc was studied, the effects of tending thinning on NSC content and NPK ecological stoichiometry in each organ of the plantation were investigated and analyzed by setting up thinning plots with thinning intensity of 25% (based on number of trees). The results showed that there were different NSC content and NPK ecological stoichiometric distribution characteristics of two kinds of Populus×xiaohei plantations. The contents of NSC in the leaf, branch and root of middle-aged forest were decreased by 31. 76%, 21. 19% and 38. 98% compared with those of young forest, respectively (P < 0. 05). The N content of leaf in the middleaged forest was increased by 11. 85% compared with that in the young forest (P < 0. 05). Compared with young forest, the P content of branch, stem and root of middle-aged forest decreased by 17. 57%, 35. 85% and 60. 11%, respectively (P < 0. 05), and the K content of leaf, branch, stem and root decreased by 21. 05%, 34. 67%, 22. 99% and 46. 22%, respectively (P < 0. 05). Tending thinning significantly affected the NSC content in the stem and root of young forest, and the NSC content in the branch and roots of middleaged forest (P < 0. 05). NSC content in stem of young forest increased by 29. 35%, while NSC content in root decreased by 40. 37%. The contents of NSC in branch and root of middle-aged forest increased by 12. 81% and 33. 51%, respectively. Tending thinning significantly affected N content in organs, K content in branch, P content in stem and K content in leaf and root of young forest (P < 0. 05). After tending, N content in leaf, branch, stem and root of young forest increased by 5. 77%, 15. 68%, 53. 71% and 10. 85%, respectively, K content in branch increased by 36. 90%, and P content in stem decreased by 19. 63%. The K content in the leaf and root of the middle-aged forest increased by 20. 86% and 31. 69%, respectively. The NSC content in leaf was negatively correlated with N content (P < 0. 01), and positively correlated with K content (P < 0. 05); NSC content in branch was negatively correlated with N content, positively correlated with P content (P < 0. 05), and significantly positively correlated with K content (P < 0. 01); NSC content in stem was significantly positively correlated with N content (P < 0. 01); NSC content in root was significantly negatively correlated with N content, and significantly positively correlated with P content (P < 0. 01). The above results showed that the distribution pattern of NSC and N, P and K elements in the organs of young and middle-aged Populus×xiaohei were significantly different when the stands were not tended. The carbon resources of the young forest were more allocated to the root system to promote its growth and extension, and the middle-aged forest was more invested in the growth and competition of the aboveground part of the tree. The distribution pattern of NSC, N, P and K in each organ was changed by tending thinning. The proportion of carbon resources in the aboveground and underground parts of the two kinds of standing Populus×xiaohei changed after tending. Tending thinning of middle age Populus×xiaohei forest increased the carbon sink and improved the P limit. [ABSTRACT FROM AUTHOR]

To study the identification of burned areas and post fire vegetation restoration in the Daxing′an Mountains region, based on Landsat TM remote sensing images from 2006 to 2020, Google Earth Engine was used to write code. The research background was the 2006 forest fire in the Nayuan Forest Farm in the Songling District of the Daxing′an Mountains region. The differential normalized burned ratio (dNBR) data was used to identify the burned areas, and the severity was classified into mild, moderate, severe, and extremely severe levels. Based on the Enhanced Vegetation Index (EVI) values of burned areas, methods such as univariate linear regression analysis, Mann-Kendall mutation test for climate diagnosis and Theil-Sen media trend analysis for treud analysis were used to analyze the vegetation restoration characteristics of burned areas from 2006 to 2020, and to explore the process of vegetation restoration in the Daxing′an Mountains region. The results showed that, 1) Based on dNBR, the burned areas in the study area was 2 488. 7 hm2, with 23. 5%, 9. 6%, 35. 2%, and 31. 7% of the areas affected by mild, moderate, severe, and extremely severe fires, respectively. Severe and extremely severe areas of excessive fire were distributed in the western and eastern parts of the burned area, and the severity of excessive fire gradually decreased from the central to the southern and northern parts. The EVI values decreased by about 30%, 40%, 58%, and 67% compared to before the fire, respectively. 2) The recovery rate of EVI in forest burned areas with different intensities showed extremely severe, severe, moderate, mild. During the vegetation restoration process, the EVI value of the burned areas gradually increased. Mild and moderate burned areas can recover 6-8 years after the fire, while the recovery of severely burned areas required 14 years. 3) During the restoration process of burned areas, there were fewer EVI mutation points in forested areas compared to grasslands, indicating stronger stability of forest ecosystems compared to irrigated grasslands. There were also certain differences in the mutation situation of forest burning sites with different intensities, and the mutation time point in the control area lagged behind the burning sites. [ABSTRACT FROM AUTHOR]

By introducing the local density factor into the taper equation, five Larix olgensis plantations in Mengjiagang Forest Farm, Jiamusi City, Heilongjiang Province, were scanned by TLS. The tree height, diameter at breast height and diameter at different relative heights of Larix olgensis were extracted from the collected point cloud data. Based on Kozak variable exponential taper equation, a taper equation with local density factor was constructed, and the fitting result was R²adj=0. 935, RMSE=0. 735 6, Bias=0. 869 3. The research showed that: the taper equation model with local density factor had good fitting accuracy, Compared with the traditional Kozak taper equation model and the taper equation model with global density factor, the taper equation model with local density factor had better fitting effect. The calculation range of the local density factor of the Larix olgensis taper equation was positively correlated with tree height and diameter at breast height. The experimental results can provide a theoretical basis for scientific and reasonable timber production in Mengjiagang Forest Farm, and preliminarily reveal the influence of local density factor on the trunk shape of Larix olgensis. [ABSTRACT FROM AUTHOR]

Pyroxasulfone is a very long chain fatty acid (VLCFA) inhibitor (group 15) with potential for preemergence weed control in orchard crops and would be beneficial for reducing selection pressure for resistance to more commonly used herbicides, such as glyphosate. Pyroxasulfone is registered and widely used in corn and soybeans in the United States as a solo product and in several premix formulations. However, there is limited published information on the performance and safety of pyroxasulfone in tree nut orchard systems. To assess the potential fit for pyroxasulfone in this crop sector, a series of crop safety and weed control efficacy experiments were carried out in key California orchard crops and in fallow fields with common orchard weeds. The non-crop studies were conducted near Davis, CA, to evaluate winter annual weed control with pyroxasulfone in comparison with pendimethalin and indaziflam. In addition, an irrigation incorporation experiment was conducted in summer to evaluate the effects of incorporation timing on pyroxasulfone, pendimethalin, and indaziflam efficacy as a measure of relative stability. Orchard weed control experiments were conducted in spring in an almond orchard near Arbuckle, CA, and a walnut orchard near Davis, CA. The orchard experiments included pyroxasulfone, pendimethalin, and indaziflam in various rate combinations with glufosinate. To evaluate crop safety, 2-year experiments were conducted to evaluate repeated applications of above-label rates of pyroxasulfone at 1199 g⋅ha-1 and S-metolachlor at 14,010 g⋅ha-1 on 1- to 2-year-old almond, pistachio, and walnut trees near Davis. Pyroxasulfone performed similarly to commercial standards with up to 95% control of broadleaf and grass weeds with pyroxasulfone and indaziflam providing 96% to 100% control of annual bluegrass, and pyroxasulfone (293 g⋅ha-1) being the only herbicide to suppress (>70%) common lambsquarters at 60 days after treatment (DAT). Other weeds controlled by pyroxasulfone include swinecress, redroot pigweed, yellow nutsedge, and Italian ryegrass. No differences were found among treatments in the incorporation timing study indicating adequate stability on the soil surface under summer conditions. Crop injury was not observed in the established orchards or the young orchard studies and there were no treatment effects on tree trunk diameter of almond, pistachio, and walnut in the 2-year crop safety experiments. These results indicate a potential for pyroxasulfone in California tree nut orchard systems that would be an additional site of action and beneficial for management of herbicide-resistant weeds in these crops. [ABSTRACT FROM AUTHOR]

Warming and drying trends in the Mediterranean Basin exacerbate regional water scarcity and threaten agricultural production, putting global food security at risk. This study aimed to review the most significant research on future water availability for the Mediterranean agricultural sector under climate change (CC) scenarios published during 2009–2024. Two searches were performed in the Scopus and Web of Science databases, to which previously identified significant studies from different periods were also added. By applying a methodology duly protocoled in the PRISMA2020-based guideline, a final number of 44 particularly relevant studies was selected for review. A bibliometric analysis has shown that most of the published research was focused on Southwestern European countries (i.e., Spain, Italy, Portugal) and grapevine and olive tree crops. Overall, the reviewed studies state that future Mediterranean water reserves may not meet agricultural water demands, due to reduced reservoir inflows and higher irrigation demands under future CC and socioeconomic scenarios. Regarding adaptation measures to improve water-use management in agriculture, the majority of the reviewed studies indicate that the use of integrated modelling platforms and decision–support systems can significantly contribute to the development and implementation of improved water/land-management practices. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Wildland Fire Science is the property of Journal of Wildland Fire Science Editorial Office 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 Journal of Wildland Fire Science is the property of Journal of Wildland Fire Science Editorial Office 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.)

This paper investigates the efficacy of weather derivatives as a risk management tool in the agricultural sector of Naousa, Greece, focusing on tree crops sensitive to temperature variations. The specific purpose is to assess how effectively weather derivative options can mitigate financial risks for farmers by providing strategic solutions. The study assesses the strategic application of Heating Degree Days (HDD) index options and their potential to alleviate economic vulnerabilities faced by farmers due to temperatures fluctuations. Employing different strike prices in Long Call and Straddle options strategies on the HDD index, the research offers tailored risk management solutions that cater to varying risk aversions among farmers. Moreover, the study applies the Value at Risk (VaR) methodology to quantify the financial security that weather derivatives can furnish, revealing a significantly reduced probability of severe financial losses in hedged scenarios compared to no-hedge conditions. Results show that all implemented strategies effectively enhance financial outcomes compared to scenarios without hedging, highlighting the exceptional utility of weather derivatives as risk management tools in the agricultural sector. Strategy 4, which exhibits the lowest VaR, emerges as the most effective, providing substantial protection against adverse weather conditions. This research supports the notion that weather derivatives can substantially contribute to the economic sustainability of rural economies, influencing policy decisions toward enhancing financial instruments for risk management in agriculture. [ABSTRACT FROM AUTHOR]

The present study was designed to assess the allelopathic potential of invasive weed Ageratina adenophora leaf extracts on seed germination and seedling development efficiency of native tree [viz. Quercus leucotrichophora A. Camus (Oak) and Pinus roxburghii Sarg. (Pine)] and crop [(Triticum aestivum L. (Wheat) and Lens culinaris Medik. (Lentil)] species of Kumaun Himalaya. Pot experiments were conducted in the glasshouse of the Botany Department, D.S.B. Campus, Kumaun University Nainital, following a Completely Randomized Block Design (CRBD) with three treatments (C1-25%, C2-50%, and C3-100% of aqueous leaf extract) and one control, each with five replicates. The experiment lasted one year for tree species and continued until the seed maturation phase for crop species. Parameters such as seed germination proportion, root and shoot measurements, biomass, and crop productivity traits were recorded accordingly. Our bioassay results indicated that the inhibitory effect of leaf extracts on the measured traits of the selected native species was proportional to the applied extract concentrations of A. adenophora. Overall, lentil among crops and oak among tree species exhibited more inhibition compared to wheat and pine, respectively. At the highest concentration, reductions of 44%, 34%, 36%, and 24% in biomass production capacity were recorded for wheat, lentil, pine, and oak, respectively, while wheat and lentil productivity decreased by up to 33% and 45%, respectively. These results suggest that water-soluble allelochemicals produced by A. adenophora may impede the establishment of selected crop and tree species in agroecosystems and forest ecosystems invaded by this weed species. However, further studies on the characterization of phytochemicals and their specific role in seed germination and growth are warranted. Furthermore, the allelopathic potential of A. adenophora can be explored for the preparation of biopesticides and nature-friendly option to improve soil health, crop productivity, and reduce environmental pollution and management of this invasive weed. [ABSTRACT FROM AUTHOR]

Panama is a habitat for nine primate species, and most of them are threatened. This has shown a fundamental concern in primate conservation by Panamanian-based conservation projects. Among them is the project Conservación del Mono Cariblanco en Agroecosistemas (COMOCA) which initiated a primate conservation education program in Southwestern Panama in 2022. The first stage of this program consisted of evaluating the perceptions that 102 children aged 8-12 years old have about primate habitat. I analyzed drawings made by these children exploring three different themes: (1) description of primate species, (2) primate habitat, and (3) food related to primates. The results indicate that children are more familiar with the white-faced capuchins and squirrel monkeys. Despite 89.2% of the children drawing trees, most of them painted tree crops. Thus, the top three most mentioned foods eaten by monkeys were mango, plantain/banana, and apple. These findings highlight the importance of addressing the relationship between primates and native trees in the content of the conservation education program. Additionally, the study illustrates how children’s depiction of their reality has implications for the management of human-primate interfaces. [ABSTRACT FROM AUTHOR]

Four new modes of action, oxathiapiprolin, fluopicolide, mandipropamid, and ethaboxam, have or are pending registrations on multiple tree crops in the USA including avocado, citrus, almond (and other tree nuts), and stone fruits to be used in sustainable anti-resistance rotation and mixture programs for managing Phytophthora diseases. All four fungicides are highly toxic in vitro against species of Phytophthora from different tree crops. Efficacy of foliar applications of oxathiapiprolin and mandipropamid for the management of citrus brown rot persisted for over 10 weeks. Still, residues could be removed to non-detectable levels by postharvest washing and brushing of fresh-market fruit. The four fungicides were highly effective in reducing root rot and crown/trunk cankers on tree crops and demonstrated acropetal systemic movement through the xylem after soil application and absorption by almond, citrus, and cherry roots. This was substantiated by reduced lesion size in stem inoculations of potted trees that were treated by soil applications or by in vitro bioassays and HPLC–MS–MS analyses of root, stem, and leaf extracts. Using an adapted Bromilow model that is based on the partition coefficient logP that indicates the lipo- or hydrophilicity and the acid dissociation constant pKa, mobility of ethaboxam, fluopicolide, mandipropamid, and oxathiapiprolin in plants was predicted, and this was supported by our studies. Mandipropamid and a mandipropamid–oxathiapiprolin pre-mixture are now registered as foliar applications for managing citrus brown rot, whereas oxathiapiprolin and fluopicolide are registered, and ethaboxam is pending registration as soil applications to control citrus root rot. Oxathiapiprolin has also been registered for soil use on almond and other nut crops, as well as avocado, and soil applications of mandipropamid are planned to be restricted to nursery use of multiple crops. [ABSTRACT FROM AUTHOR]

Growing perennial legumes in the understory layer in agroforestry systems is a strategy to improve the sustainability of agricultural systems, i.e., by increasing land productivity, fostering carbon sequestration and nutrient cycling and reducing reliance on inorganic nitrogen fertilizers for tree crops. In many parts of Central Italy, sulla, a biennial autochthonous legume, is widely adopted in forage cropping systems for its productivity and nutritive value and it is often intercropped with ryegrass for a better utilization as grazed temporary grassland. To evaluate the agronomic performance of these perennial species grown under different levels of light reduction, an artificial shade plot trial was established in the coastal plain of Pisa, Central Italy, with the aim to simulate the effect of tree presence with different levels of shade intensification in rainfed conditions. The experiment layout complies with a 2-way completely randomized design with four replicates. The two factors tested were the forage species (namely sulla, ryegrass and their intercropping) and the level of shade (no shade, moderate shade − 30% light reduction-, and intense shade − 50% light reduction-). Shading significantly reduced the above ground biomass (AGB) production, especially for the intense shading (on average about − 20% with respect to the full sun). The mixture resulted as the most productive crop, yielding on average about + 30 and + 40% AGB in comparison to sulla and ryegrass pure stands, respectively. The findings about the effect of the shading on AGB production showed that mixture was a suitable sward, especially under moderate shading conditions. Further studies are needed with the purpose to investigate the productive performance of these swards in real agroforestry conditions. [ABSTRACT FROM AUTHOR]

Herbicide flashback is an undesirable response that results in damage or mortality of non-target plants near chemically treated plants. In severe instances, crop trees can be injured resulting in financial loss or inability to capture management objectives. Land managers need to know the potential limitations of using triclopyr acid (50% solution in water) and what quantity can cause damage to non-target trees (trees not aimed at for control via herbicide). Three naturally regenerated (previously clearcut) bottomland hardwood sites, ranging from 14–20 years of age, received partial overstory deadening using Trycera® herbicide. Residual "leave" trees experienced indirect herbicide uptake resulting in some trees either experiencing mortality or partial mortality with top dieback/epicormic branching. An increased probability of damage occurred as tree diameter decreased and the number of treated stems around the non-target stems increased. American sycamore, green ash, and sweetgum were most susceptible to flashback. This study examines the unanticipated chemical effect of deadening adjacent stems surrounding residual leave trees in poorly drained soils. [ABSTRACT FROM AUTHOR]

The United States (US) apple industry relies heavily on semi‐skilled manual labor force for essential field operations such as training, pruning, blossom and green fruitlet thinning, and harvesting. Blossom thinning is one of the crucial crop‐load management practices to achieve desired crop load, fruit quality, and return bloom. While several techniques such as chemical and mechanical thinning are available for large‐scale blossom thinning, such approaches often yield unpredictable thinning results and may damage the canopy, spurs, and leaf tissue. Hence, growers still depend on laborious, labor‐intensive, and expensive manual hand blossom thinning for desired thinning outcomes. This research presents a robotic solution for precision blossom thinning in apple orchards using a deep learning‐based computer vision system, a six‐degrees‐of‐freedom UR5e robotic manipulator, and an electrically actuated miniature end‐effector. The integrated robotic system was evaluated in a commercial apple orchard which showed promising results for targeted and selective blossom thinning. Two thinning approaches, center and boundary thinning, were investigated to evaluate the system's ability to remove varying proportions of flowers from apple flower clusters. During boundary thinning, the end‐effector was actuated around the cluster boundary, while center thinning involved end‐effector actuation only at the cluster centroid for a fixed duration of 2 s. Field evaluation results showed that the boundary thinning approach thinned 67.2% of flowers from the targeted clusters with a cycle time of 9.0 s per cluster, whereas the center thinning approach thinned 59.4% of flowers with a cycle time of 7.2 s per cluster. Upon further improvement for commercial adoption, the proposed system could help address problems faced by apple growers with current hand, chemical, and mechanical blossom thinning approaches. [ABSTRACT FROM AUTHOR]

The recent deployment of new satellite-based hyperspectral imaging sensors, along with advances in classification methods, has enhanced the acquisition of information on the spatiotemporal patterns of Land Use/Land Cover (LULC).. With this context, the study presented in this paper seeks to assess the combined utilization of the Pixxel's technology demonstrator hyperspectral satellite mission with the Support Vector Machines (SVM) and Random Forest (RF) machine learning classifiers for LULC mapping in an agricultural area located in Queensland, Australia. Accuracy assessment of the resulting LULC maps has been done based on relevant classification accuracy metrics. It has been observed that SVMs outperformed RF in terms of both overall classification and urban vegetation cover mapping accuracy. An overall accuracy of 92.34% with kappa of 0.90 was reported for the SVMs' results, whereas for RF, the accuracy was 89.65% with 0.89 kappa, respectively. Both classifiers produced similar results for the classes of mango tree and sugarcane crops, whereas minor differences were observed in the depiction of water bodies and artificial surfaces. Our study findings provide insightful perspectives on the potential of Pixxel datasets for delineating the spatiotemporal distribution of LULC in agricultural landscapes, showcasing Pixxel's hyperspectral sensors' promising potential in this field. [ABSTRACT FROM AUTHOR]

Advances in molecular ecology can overcome many challenges in understanding host–parasitoid interactions. Genetic characterization of the key-players in systems helps to confirm species and identify trophic linkages essential for ecological service delivery by biological control agents; however, relatively few agroecosystems have been explored using this approach. Pecan production consists of a large tree perennial system containing an assortment of seasonal pests and natural enemies. As a first step to characterizing host–parasitoid associations in pecan food webs, we focus on aphid species and their parasitoids. Based on DNA barcoding of field-collected and reared specimens, we confirmed the presence of 3 species of aphid, one family of primary parasitoids, and 5 species of hyperparasitoids. By applying metabarcoding to field-collected aphid mummies, we were able to identify multiple species within each aphid mummy to unravel a complex food web of 3 aphids, 2 primary parasitoids, and upward of 8 hyperparasitoid species. The results of this study demonstrate that multiple hyperparasitoid species attack a single primary parasitoid of pecan aphids, which may have negative consequences for successful aphid biological control. Although further research is needed on a broader spatial scale, our results suggest multiple species exist in this system and may suggest a complex set of interactions between parasitoids, hyperparasitoids, and the 3 aphid species. This was the first time that many of these species have been characterized and demonstrates the application of novel approaches to analyze the aphid-parasitoid food webs in pecans and other tree crop systems. [ABSTRACT FROM AUTHOR]

Little Corellas (Cacatua sanguinea) are notorious for damaging crops and ornamental trees, and are an overabundant nuisance native in some urban areas. Habitat and landscape use studies ideally require the attachment of tracking devices. Here, we describe an attempt to attach GPS transmitters to Little Corellas using the backpack and keel-strap harness method. All five tracking devices initially attached to Little Corellas were removed by the birds within 48-hours. Additionally, a conspecific was observed chewing on the Teflon ribbon of a GPS harness shortly after the release of a Little Corella; a novel record that suggests cooperative abilities for the species. To complement our study, we conducted a literature review of parrot (psittacine) tracking studies. We investigated attachment styles and potential reasons for past device removals. Of the 46-relevant studies, neck collars were the most common attachment method (38.8%), followed by backpack harnesses (24.5%). Transmitter removal was documented in 28.3% of studies, with removals being most common for medium-sized (500–1000 g) species, and for combination (simultaneous back- and tail-mounts; n = 4) and backpack harness attachments (n = 6). Although there are relatively few parrot telemetry studies to date, they are increasing, and future studies will require considerable innovation and collaboration to overcome attachment style hurdles for difficult species, like the Little Corella. [ABSTRACT FROM AUTHOR]

Variable-density thinning (VDT) can be used to start the conversion of young homogeneous conifer plantations to the single-tree selection system. A design for VDT is presented, which is adapted to harvester-based operations in northern Europe without prior tree marking and the low target diameters in the region. Six treatment cells with a size of 10 × 10 m are placed along a 30 m stretch of a strip road with treatments gap (removing all but understory trees), skip (no thinning), and four treatment cells with crop tree-based crown thinning, which removes two dominant competitors of 1–4 crop trees per cell. Skips might in later thinnings be converted into gaps, which is why skips and gaps are placed systematically in the 2 × 3 treatment blocks. Assignment of the crop tree number variants to treatment cells are decided by the harvester operator based on the given stand structure and presence of crop trees meeting all selection criteria. So far, five operations have confirmed the practicality of this design and given some insight into the learning process of harvester operators with these new methods. [ABSTRACT FROM AUTHOR]

Targeted precise management of intravascular diseases such as citrus Huanglongbing (HLB) involves the application of therapeutics via trunk injection. Although trunk injection has proven more effective than foliar spray and soil drenching, multiple studies have highlighted limitations for large-scale commercial tree crop applications because of the manual process involved, emphasizing the need for an automated injection system. The design of a trunk injection mechanism to efficiently dispense aqueous therapeutic materials to the trunk of HLB-affected citrus trees requires the characterization of the hydraulic properties of the trunk and the determination of the penetration force of a dispensing needle. This study developed an equation for estimating penetration force at maximum depth based on the needle diameter, depth of penetration, and specific gravity of the wood tissue, and presents a method for estimating injection pump pressure. Trunk hydraulic conductance was measured using a hydraulic conductance flow meter, and needle insertion and removal force were measured using a force gauge in an Instron universal testing machine. The average maximum force was 2517, 3739, and 5387 N for dowel pins 4.76, 6.35, and 7.93 mm in diameter at a 12 mm penetration depth. Average specific conductivity was 2.45, 0.34, and 0.15 kgs-1m-1MPa-1for trunk segments 0-12.7, 12.7-26.7, and 26.7-40.6 cm above the ground, with a corresponding estimated pump pressure of 0.14, 0.99, and 2.31 MPa, respectively. [ABSTRACT FROM AUTHOR]

Farming practices of the past century have dramatically increased annual crop yields to unprecedented levels but have consequentially created increasing ecological and public health concerns, posing a long‐term threat to global food security. Soil tillage and chemical inputs perpetuate soil erosion, biodiversity loss, wetlands eutrophication, carbon emissions, and other farming stressors. Concomitantly, accompanying poor dietary patterns and malnutrition increase the risk for chronic diseases, such as cardiovascular diseases, obesity, type 2 diabetes, and cancer, which account for greater than 70% of global mortality per annum. Altogether, such annual monocropping systems exacerbate food insecurity, necessitating action across the fields of public health, agriculture, nutrition, medicine, and environmental ecology, that is, a transdisciplinary approach. Herein, we argue that the perennialization of crops creates an opportunity to address the challenges of environmental sustainability and nutritional adequacy economically. Unlike annuals, perennial crops have deeper roots for increased drought tolerance and reduced needs for fertilization and irrigation. Adopting perenniality can result in greater drought tolerance and improved soil health while reducing erosion, farming labor, and seed purchasing. Furthermore, perennializing novel staple crops may offer a superior and diverse dietary profile of phytochemicals, fiber, and macronutrients compared to conventional annuals. Instead of traditional perennial tree crops, we focus on intermediate wheatgrass Kernza® (Thinopyrum intermedium) and sunflowers (Helianthus tuberosus, H. maximiliani, and Silphium integrifolium) as exemplars of perennial staple food crops for grain and oil, respectively, at different stages of perennial crop commercialization. Ultimately, we discuss how integrating perenniality has the potential to revolutionize global agriculture and address food security concerns for the remainder of the 21st century. [ABSTRACT FROM AUTHOR]

Native forests host important pools of soil organic carbon (SOC). This is a key element not only for ecosystem functioning but also for the global carbon cycle. Globally, and particularly in Argentina, native forests are being rapidly replaced by other land uses, raising questions about the impact of these transformations on SOC and its environmental controls. Based on the construction of the largest SOC database in Argentina to date, we investigated the patterns and controls of changes in SOC stocks associated with the replacement of native forests by other land uses. We constructed the database with a total of 818 sites with SOC data (0–30 cm depth), covering the main ecoregions, to which we added environmental information (e.g. satellite data, soil database and climate database), to study the environmental controls on SOC change after deforestation and on the original SOC content of native forests. Considering all ecoregions and all land use alternatives together, we found an average decrease in SOC stock of 18.2 Mg C ha−1, which represents a loss of more than a quarter of the original SOC stock of the native forest sites. A boosted regression tree explained 89% of the variation in SOC stock change and indicated that the initial forest SOC stock and the post‐deforestation land use were the most important variables explaining this variation (relative influence of 30.9% and 18.2%, respectively). The replacement of native forests by rainfed annual crops resulted in the largest decrease in SOC (−28 Mg C ha−1), which was twice as large as the decrease observed in rangelands (−14 Mg C ha−1). On the contrary, neither irrigated croplands nor tree plantations of fast‐growing species caused a decrease in SOC stocks (p >.10). Climate and soil texture had an indirect effect on SOC changes through a strong influence on the initial SOC stocks in native forests (p <.01). Our study highlighted the significant impact of land use change on SOC stocks, overshadowing other relevant environmental controls. Understanding how the SOC pool responds to land use change, environmental conditions and management practices is essential to increase the effectiveness of practices implemented to improve soil properties and mitigate climate change. [ABSTRACT FROM AUTHOR]

Agroforestry has the potential to support more resilient livelihoods, soil health, and biodiversity, when compared to monocropping. In Ecuador, the Union of Cacao Peasant Organizations (UNOCACE) has been working with producers since 2016 to transition cacao plots to a dynamic agroforestry system that includes timber and fruit species as well as ground cover in addition to cacao. This study evaluates the application of this model and its implications for agricultural production, livelihoods, and soil health through producer surveys and field-based sampling. The program is resulting in significantly more timber and fruit trees on the cacao plots. Despite this, cacao production and income have not decreased in a significant way, once accounting for the number of producing trees on the plots. In addition, while additional labor is utilized on the dynamic agroforestry plots, after utilizing a matching procedure, no significant difference is seen in total crop productivity for each day of labor utilized. Over time, total productivity could increase for the dynamic agroforestry plots as the companion crops and trees mature. As the program is relatively new and has undergone some changes, additional studies are needed to understand the benefits or challenges, especially for soil health, that might be realized further in the lifespan of the program. [ABSTRACT FROM AUTHOR]

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Carbon sequestration by photosynthetic organisms is the principal mechanism for the absorption of atmospheric CO2. Since the 1950s, however, the global carbon cycle has been distorted as increased anthropogenic CO2 emissions have greatly outstripped rates of carbon sequestration, with a 50% increase in atmospheric CO2 levels in less than a century, leading to perturbation of global climate systems and threatening food production and social stability. In order to address the current imbalance in CO2 flux, it is important to both reduce net emissions and promote sequestration. To address the latter issue, we need to better understand the roles of systems, such as natural forests, coastal wetlands, and tropical croplands, in carbon sequestration and devise strategies to facilitate net CO2 uptake. Carbon sequestration by tropical trees and crops already removes in excess of 1000 million tonnes of atmospheric CO2 annually but is threatened by anthropogenic activities such as deforestation and the drainage of carbon-rich peatland. Improvements in carbon sequestration can be achieved by policies such as growing tropical crops as part of agroforestry systems, enforcing limitations on deforestation and the use of peatland, and auditing the carbon impact of major cropping systems in order to focus on those crops that deliver both high yields and carbon efficiency. As an initial step in this process, a detailed case study is presented on the tropical tree crop, the African oil palm, Elaeis guineensis. This analysis includes a comparison of the carbon sequestration potential of oil palm with that of tropical forests and other oil crops, the biomass sequestration potential of oil palm and current and future strategies aimed at achieving net-zero carbon targets for oil palm and related crops. [ABSTRACT FROM AUTHOR]

Agroforestry is often seen as a sustainable land-use system for agricultural production providing ecosystem services. Intercropping with food crops leads to equal or higher productivity than monoculture and results in food production for industry and subsistence. Low rubber price and low labor productivity in smallholdings have led to a dramatic conversion of rubber plantations to more profitable crops. The literature analysis performed in this paper aimed at better understanding the ins and outs that could make rubber-based agroforestry more attractive for farmers. A comprehensive search of references was conducted in March 2023 using several international databases and search engines. A Zotero library was set up consisting of 415 scientific references. Each reference was carefully read and tagged in several categories: cropping system, country, main tree species, intercrop type, intercrop product, level of product use, discipline of the study, research topic, and intercrop species. Of the 232 journal articles, 141 studies were carried out on rubber agroforestry. Since 2011, the number of studies per year has increased. Studies on rubber-based agroforestry systems are performed in most rubber-producing countries, in particular in Indonesia, Thailand, China, and Brazil. These studies focus more or less equally on perennials (forest species and fruit trees), annual intercrops, and mixed plantations. Of the 47 annual crops associated with rubber in the literature, 20 studies dealt with rice, maize, banana, and cassava. Agronomy is the main discipline in the literature followed by socio-economy and then ecology. Only four papers are devoted to plant physiology and breeding. The Discussion Section has attempted to analyze the evolution of rubber agroforestry research, progress in the selection of food crop varieties adapted to agroforestry systems, and to draw some recommendations for rubber-based agroforestry systems associated with food crops. [ABSTRACT FROM AUTHOR]

Phytophthora cinnamomi is a devastating soil-borne plant pathogen. The primary source of P. cinnamomi infection is the soil, where the pathogen can persist for long periods. Effective prevention and management of this pathogen in tree crops requires an early and reliable detection method. In this study, we developed a simple, fast, reliable, and sensitive method based on real-time quantitative PCR (qPCR) for P. cinnamomi detection and quantification directly in plant or soil samples. Primers were developed targeting the nuclear single-copy ras-related protein gene Ypt1, suitable for Phytophthora-specific PCR. The specificity of the assay was confirmed by testing it against genomic DNA from 50 isolates across eight different Phytophthora clades, including the very similar P. parvispora. The efficiency and reliability of the qPCR protocol were evaluated in challenging environmental samples, such as plant tissue of different host trees (walnut, chestnut, oak) and naturally infected soils in walnut orchards. The main outcome was the development of a qPCR method for the specific identification and quantification of P. cinnamomi in natural soil samples. Additionally, this study established a systematic and repeatable soil sampling method and developed an efficient soil DNA extraction technique to apply the developed qPCR in naturally infested soils of walnut orchards. [ABSTRACT FROM AUTHOR]

Background: Theobroma cacao, the cocoa tree, is a tropical crop grown for its highly valuable cocoa solids and fat which are the basis of a 200-billion-dollar annual chocolate industry. However, the long generation time and difficulties associated with breeding a tropical tree crop have limited the progress of breeders to develop high-yielding disease-resistant varieties. Development of marker-assisted breeding methods for cacao requires discovery of genomic regions and specific alleles of genes encoding important traits of interest. To accelerate gene discovery, we developed a gene atlas composed of a large dataset of replicated transcriptomes with the long-term goal of progressing breeding towards developing high-yielding elite varieties of cacao. Results: We describe the creation of the Cacao Transcriptome Atlas, its global characterization and define sets of genes co-regulated in highly organ- and temporally-specific manners. RNAs were extracted and transcriptomes sequenced from 123 different tissues and stages of development representing major organs and developmental stages of the cacao lifecycle. In addition, several experimental treatments and time courses were performed to measure gene expression in tissues responding to biotic and abiotic stressors. Samples were collected in replicates (3–5) to enable statistical analysis of gene expression levels for a total of 390 transcriptomes. To promote wide use of these data, all raw sequencing data, expression read mapping matrices, scripts, and other information used to create the resource are freely available online. We verified our atlas by analyzing the expression of genes with known functions and expression patterns in Arabidopsis (ACT7, LEA19, AGL16, TIP13, LHY, MYB2) and found their expression profiles to be generally similar between both species. We also successfully identified tissue-specific genes at two thresholds in many tissue types represented and a set of genes highly conserved across all tissues. Conclusion: The Cacao Gene Atlas consists of a gene expression browser with graphical user interface and open access to raw sequencing data files as well as the unnormalized and CPM normalized read count data mapped to several cacao genomes. The gene atlas is a publicly available resource to allow rapid mining of cacao gene expression profiles. We hope this resource will be used to help accelerate the discovery of important genes for key cacao traits such as disease resistance and contribute to the breeding of elite varieties to help farmers increase yields. [ABSTRACT FROM AUTHOR]

Introduction: The coconut tree crop (Cocos nucifera L.) provides vital resources for millions of people worldwide. Coconut germplasm is largely classified into 'Tall' (Typica) and 'Dwarf' (Nana) types. While Tall coconuts are outcrossing, stress tolerant, and late flowering, Dwarf coconuts are inbred and flower early with a high rate of bunch emission. Precocity determines the earlier production of a plantation and facilitates management and harvest. Methods: A unique outbred F2 population was used, generated by intercrossing F1 hybrids between Brazilian Green Dwarf from Jiqui (BGDJ) and West African Tall (WAT) cultivars. Single-nucleotide polymorphism (SNP) markers fixed for alternative alleles in the two varieties, segregating in an F2 configuration, were used to build a high-density linkage map with ~3,000 SNPs, anchored to the existing chromosome-level genome assemblies, and a quantitative trait locus (QTL) mapping analysis was carried out. Results: The linkage map established the chromosome numbering correspondence between the two reference genome versions and the relationship between recombination rate, physical distance, and gene density in the coconut genomes. Leveraging the strong segregation for precocity inherited from the Dwarf cultivar in the F2, a major effect QTL with incomplete dominance was mapped for flowering time. FLOWERING LOCUS T (FT) gene homologs of coconut previously described as putatively involved in flowering time by alternative splice variant analysis were colocalized within a ~200-kb window of the major effect QTL [logarithm of the odds (LOD) = 11.86]. Discussion: Our work provides strong phenotype-based evidence for the role of the FT locus as the putative underlying functional variant for the flowering time difference between Dwarf and Tall coconuts. Major effect QTLs were also detected for developmental traits of the palm, plausibly suggesting pleiotropism of the FT locus for other precocity traits. Haplotypes of the two SNPs flanking the flowering time QTL inherited from the Dwarf parent BGDJ caused a reduction in the time to flower of approximately 400 days. These SNPs could be used for high-throughput marker-assisted selection of early-flowering and higher-productivity recombinant lines, providing innovative genetic material to the coconut industry. [ABSTRACT FROM AUTHOR]

Shade trees in agroforestry systems confer ecosystem services, such as enhanced soil fertility from diverse litter inputs, microclimate regulation via shade, and disease mitigation through trophic and abiotic interactions. With this thriving role of agroforestry in sustainable agriculture, particularly for tree crops, systematic and reliable methods to select shade trees for specific agroecosystem outcomes are crucial.Plant functional traits offer a framework to describe, select and manage shade trees. Over the last decade, shade tree leaf functional traits and whole plant traits have been assessed in agroforestry systems. Yet, we lack amalgamated information on (i) what we know about shade tree trait relationships with functions to achieve desired agroecosystem outcomes, (ii) how decades of shade tree selection by farmers impacts agroforests inter‐ and intraspecific trait diversity, and (iii) which shade tree traits should be considered for achieving farmer priorities.We consolidate literature on Coffea arabica (coffee) and Theobroma cacao (cocoa) agroforestry systems to summarize the role of shade tree functional traits in three key ecosystem functions: soil fertility, microclimate modification and crop productivity. We compile global and regional datasets on tree functional trait diversity to show the functional space of agroforestry tree species compared with the overall functional space observed in plants.Despite, or maybe because of, high shade tree diversity, shade tree trait characterization remains coarse and commonly measured at the community scale in the literature. Based on published trait data, we show that farmers adjust the functional composition of shade trees to increase the recycling of soil nutrients (high leaf nitrogen), the production of wood (skewing towards lower wood densities) and the production of fruits (tendency towards high seed size). Common shade trees in coffee and cocoa systems fall in the mid‐range of leaf acquisitive to conservative strategies, providing evidence that expanding shade tree portfolios can improve, or even accelerate, functions.Synthesis and applications: Based on the agroforestry literature and on trait‐environment relationships, we propose a matrix of shade tree traits that influence desirable agroecosystem outcomes for farmers, which can guide fine‐scale coordination of trait expression and agroforestry functions. [ABSTRACT FROM AUTHOR]

European hazelnut (Corylus avellana L.) is an important tree nut crop. Hazelnut production in North America is currently limited in scalability due to Anisogramma anomala , a fungal pathogen that causes Eastern Filbert Blight (EFB) disease in hazelnut. Successful deployment of EFB resistant cultivars has been limited to the state of Oregon, where the breeding program at Oregon State University (OSU) has released cultivars with a dominant allele at a single resistance locus identified by classical breeding, linkage mapping, and molecular markers. C. avellana cultivar "Jefferson" is resistant to the predominant EFB biotype in Oregon and has been selected by the OSU breeding program as a model for hazelnut genetic and genomic research. Here, we present a near complete, haplotype-resolved chromosome-level hazelnut genome assembly for " Jefferson". This new assembly is a significant improvement over a previously published genome draft. Analysis of genomic regions linked to EFB resistance and self-incompatibility confirmed haplotype splitting and identified new gene candidates that are essential for downstream molecular marker development, thereby facilitating breeding efforts. [ABSTRACT FROM AUTHOR]

The productivity of many tree crops is limited by low yield, partly due to high rates of fruitlet abscission during early fruit development. Early studies suggested that cross-pollinated fruitlets may be selectively retained during fruit development, although paternity testing of fruitlets to test this hypothesis was technically challenging. We used MassARRAY genotyping to determine the effects of pollen parentage on fruitlet retention and fruit quality of Hass avocado. We identified the paternity of abscised and retained fruitlets at 6 and 10 weeks, and mature fruit at 36 weeks, after peak anthesis. We measured the embryo mass, pericarp mass, total mass and nutrient concentrations of fruitlets, and the seed mass, flesh mass, total mass, diameter, length, nutrient concentrations and fatty-acid composition of mature fruit. The percentages of progeny on the tree that were cross-fertilised increased from 4.6% at 6 weeks after peak anthesis to 10.7% at fruit maturity. Only 1.0% of freshly abscised fruitlets on the ground at 10 weeks after peak anthesis were cross-pollinated even though 6.5% of retained fruitlets on the tree were cross-pollinated. At this stage, cross-pollinated fruitlets had similar nutrient concentrations to self-pollinated fruitlets, but they had higher total contents of P, K, Al, Ca, Fe, Mn and Zn due to having greater fruitlet mass. At maturity, cross-pollinated fruit were 6% heavier and had 2% greater diameter than self-pollinated fruit, without significant differences in flesh nutrient concentrations or fatty acid composition. The results demonstrate that Hass avocado trees selectively retain cross-pollinated fruitlets, which are larger than self-pollinated fruitlets and ultimately produce larger mature fruit. Avocado growers can increase fruit size and yield by improving the opportunities for cross-pollination, possibly by closely interplanting type A and type B cultivars and introducing more beehives into orchards. [ABSTRACT FROM AUTHOR]

Colletotrichum gloeosporioides is one of the more economically important pathogen causing anthracnose on crops and trees worldwide. As an essential mineral nutrient, potassium play a vital role for fundamental cellular processes in organisms. In this study, a high-affinity potassium transporter CgTrk1 was identified in C. gloeosporioides. Cytological examinations revealed that CgTrk1 was localized in the plasma membrane. The gene deletion mutant of CgTRK1 significantly depressed the potassium uptake. CgTrk1 is also required for vegetative growth, appressorium development, invasive growth, and full virulence. The data also indicate that CgTrk1 plays dominant roles in potassium uptake and pathogenicity rather than its homologous protein CgTrk2. These results imply that the potassium transporter CgTrk1 is involved in invasive growth and full virulence in C. gloeosporioides. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms by which wild bees survive in modified landscapes is important for their conservation and management as pollinators. Pollen is a critical resource for the completion of bee life cycles, so we investigated how the pollen loads carried by native bee communities change between natural forests and farms dominated by exotic crops and weeds in an agricultural region of south‐east Australia.We found that individual bees tended to carry higher proportions of exotic pollen on farms compared with forests (after accounting for whether they were captured on exotic or native flowers), and the diversity of pollen carried by bees did not differ significantly between native forest and farm sites or along native forest cover gradients. This suggests that the native bees found on farms, which are predominantly different species compared with those found in native forests, are not disadvantaged by the dominance of exotic plants in these habitats (though impacts on larval nutrition were not investigated).While some native bees carried crop pollen, others almost exclusively carried the pollen of agricultural weeds (e.g., Arctotheca and Brassica species), such that some native bee species may pollinate and benefit from crops, whereas others may only persist on farms if agricultural weeds are tolerated. [ABSTRACT FROM AUTHOR]

Local climate change impacts hit hard at smallholder farmers in developing countries due to their overreliance on rain-fed farming. Whilst ecosystem-based adaptation (EbA) to climate change holds an answer to smallholder farmers' adaptation needs, there are inadequate empirical results from the field to support formulation of effective adaptation strategies. Hence, this paper aimed at investigating EbA practices adopted by farmers, in North-Western Ghana to ameliorate local climate change impacts, with emphasis on benefits and associated challenges. The study methods were cross-sectional survey, mixed methods, and case study approach, with all data collected in the Wa West District of Ghana. Data were gathered using questionnaire, focus group discussion (FGD) and interviews. Data from the questionnaire were entered into SPSS version 20 to analyze associations between the variables using cross-tabulation. Descriptive statistics, in the form of percentages and frequencies, were then generated from the survey data and integrated with the qualitative information in the presentation of results. Also, statistical significance of the relationships was analyzed using chi-square test. Chi-squared tests were done to determine associations between socio-economic and environmental factors, and challenges and benefits associated with the adoption of EbA practices. This was necessary to give further insights to inform policy-related decisions aimed at addressing EbA adoption challenges. The results revealed that farmers use a combination of practices rather than single practice. Farmers integrated crops and trees and keep local breed of farm animals. Benefits of EbA included improvements in soil fertility leading to high crop yield and availability of food and income. Challenges of adopting EbA were the long timespan for benefits of most EbA practices to begin to accrue, lack of extension information and increasing cost of hired labour. It is recommended that tree integration should emphasis trees with multiple benefits and compatible with food crops. For the achievement of food security policy objectives, agroforestry promotion should focus on the integration of fruit tree crops and food crops to address hunger and increase farmers' incomes. Mobile extension technology should be exploited by government for the provision of EbA-specific information to farmers to bridge the extension services gap. Climate change policy of government should include the planting of non-fruit trees as windbreaks to provide multi-purpose benefits including provision of stakes for yam farmers, live-fencing and firewood for women. There is the need for government policy objectives to include EbA by farmers under the flagship 'planting for food and jobs' programme. [ABSTRACT FROM AUTHOR]

Growers have depended on the specificity and efficacy of streptomycin and oxytetracycline as a part of their plant disease arsenal since the middle of the 20th century. With climate change intensifying plant bacterial epidemics, the established success of these antibiotics remains threatened. Our strong reliance on certain antibiotics for devastating diseases eventually gave way to resistance development. Although antibiotics in plant agriculture equal to less than 0.5% of overall antibiotic use in the United States, it is still imperative for humans to continue to monitor usage, environmental residues, and resistance in bacterial populations. This review provides an overview of the history and use, resistance and mitigation, regulation, environmental impact, and economics of antibiotics in plant agriculture. Bacterial issues, such as the ongoing Huanglongbing (citrus greening) epidemic in Florida citrus production, may need antibiotics for adequate control. Therefore, preserving the efficacy of our current antibiotics by utilizing more targeted application methods, such as trunk injection, should be a major focus. [ABSTRACT FROM AUTHOR]