Walnut is valued for being rich in nutrients and polyphenols, which are key bioactive metabolites; however, a comprehensive and dynamic assessment of metabolites in the husk and pellicle is still lacking. In this study, multi-omics approaches combining untargeted metabolomics and transcriptome analysis were conducted to systematically characterize the differential metabolite profile and regulatory networks in walnut husk and pellicle. Metabolomic profiling revealed a clear divergence in polyphenol compositions between the husk and the pellicle; the husk was predominantly enriched in nine phenolic acid compounds, whereas the pellicle accumulated eleven flavonoid compounds. Through co-expression network analysis, a transcription factor, JrMYB8, was identified and shown to act as a specific inhibitor and regulator of polyphenol biosynthesis. Functional characterization demonstrated that <i>JrMYB8</i> overexpression significantly reduced the accumulation of the total phenol content (TPC) and the total flavonoid content (TFC) by directly repressing the expression of <i>JrC4H</i>. These findings not only provide a molecular target for manipulating polyphenol content in walnut tissues but also offer a target for improving flavor in walnut breeding.
Cotton, as a globally important fiber crop, is significantly affected by drought stress during production. This study uses the drought-resistant variety Jin and the drought-sensitive variety TM-1 as test materials. Through multi-period drought stress treatments at 0 d, 7 d, 10 d, 15 d, and 25 d, combined with dynamic monitoring of physiological indicators, RNA sequencing, and weighted gene co-expression network analysis, the molecular mechanism of cotton drought resistance is systematically analyzed. Dynamic monitoring of physiological indicators showed that Jin significantly accumulated proline, maintained superoxide dismutase activity, reduced malondialdehyde accumulation, and delayed chlorophyll degradation. Transcriptome analysis revealed that Jin specifically activated 8544 differentially expressed genes after stress, which were significantly enriched in lipid metabolism (α-linolenic acid, ether lipids) and secondary metabolic pathways. Weighted gene co-expression network analysis identified co-expression modules significantly correlated with proline (r = 0.81) and malondialdehyde (r = 0.86) and selected the key hub gene Gh_A08G154500 (WRKY22), which was expressed 3.2 times higher in Jin than in TM-1 at 15 days of drought stress. Functional validation suggested that WRKY22 may form a “osmotic regulation–membrane protection” co-regulatory network by activating Pro synthesis genes (P5CS) and genes involved in the jasmonic acid signaling pathway. This study reveals, for the first time, the possible dual regulatory mechanism of WRKY22 in cotton’s drought resistance, providing a theoretical basis for cotton drought-resistant breeding.
Abstract X. americana L. is an important and multipurpose woody plant tree species. Due to the multipurpose uses of the species, it is over-exploited by the nearby communities for different purposes. Additionally, the species also have poor seed viability, and seed germination as well as insufficient pollination caused by long distances between male and female trees. This research was hypothesized whether there was a good distribution and regeneration status of X. americana or not based on the diameter class distribution. This study aimed to examine the population structure, phenological attributes, and fruit yield potential of X. americana in Quara district, Northwestern Ethiopia. The study was carried out by establishing 30 sample plots (20 m × 20 m) systematically. Further, 10 × 10 m subplots were laid out under the main plot quadrants for sapling and seedling count. Thirty reproductively matured trees with easily visible crowns were selected to record phenological characteristics and fruit yield. Quantitative data were determined by computing density, frequency, dominance, importance value index, and Pearson correlation. The findings revealed that X. americana appeared in the study area at about 488.33 population densities per hectare. An inverted J-shaped diameter class distribution was observed. X. americana flower initiation starts in March and sheds its fruit at the end of June. On average, 12.26 kg of fruits per tree were recorded with a maximum of fruits in mid-diameter size class trees. To ensure the species sustainably in the area, anthropogenic factors like deliberate fire, deforestation, and overgrazing should be properly managed.
Seaweed-associated endophytic fungi have recently attracted considerable attention due to their ecological significance and potential application as biological resources. Accordingly, research efforts to isolate and characterize fungal endophytes from marine macroalgae have accelerated. This study aimed to isolate and identify endophytic fungi from two brown algae, Sargassum thunbergii and S. muticum, collected from intertidal zones in Tongyeong and Pohang, Korea. Identification was performed based on morphological characteristics and multilocus phylogenetic analyses using ITS, LSU, TEF1, TUB2, and RPB2 gene sequences. As a result, three previously unrecorded fungal species in Korea were identified: Neopyrenochaeta telephoni, Trichoderma cyanodichotomum, and Microascus intricatus. This study provides detailed descriptions of their morphological features and phylogenetic relationships. These findings contribute to a better understanding of fungal diversity associated with brown algae in Korea and highlight the potential significance of endophytic fungi in marine ecosystems.
Komivi Dossa, Mahugnon Ezékiel Houngbo, Jean-Luc Irep
et al.
Abstract Background Yams (Dioscorea spp.) are significant food security crops especially in West Africa. With the increasing tuber demand and climate change challenges, it is pertinent to strengthen breeding programs for developing high-yielding cultivars with climate resilience. The current study aimed at deciphering the genetic basis of leaf traits related to stress responses in a diverse panel of Dioscorea alata genotypes. Results Phenotypic characterization of 12 traits, including leaf dry matter content, mean leaf area, net photosynthesis, transpiration rate, transpiration use efficiency, stomatal density, stomatal index, preformed node count, leaf thickness, competitor, stress-tolerator, ruderal ecological strategies emphasized significant variations among the genotypes and across two planting locations. Weak correlations were observed among most of traits, suggesting that breeding simultaneously for some of these stress response-related traits would be possible. Heritability was highest for transpiration rate, leaf area and stomatal density, while it was lowest for stress-tolerator, ruderal ecological strategies. Genome-wide association study (GWAS) using high-quality single nucleotide polymorphism (SNPs) identified 24 significant associations on 11 chromosomes, where the association signals were consistent across two locations for traits with high heritability, viz., stomatal density (Chr18) and transpiration rate (Chr3). Further characterization of the significant signals and their related alleles identified advantageous alleles contributing positively to the studied traits. Moreover, 44 putative candidate genes were identified. Dioal.18G049300 (3 keto acyl-coenzyme A synthase) was identified as a strong candidate gene for stomatal density, while Dioal.12G033600 (Phosphatidyl inositol monophosphate 5 kinase 4) was identified for net photosynthesis. Conclusion Taken together, GWAS and allele segregation analysis for key SNPs provided significant insights into the marker-trait associations, which can be further utilized in breeding programs to improve climate resilience in greater yam.
As the world’s largest loess deposit region, the Loess Plateau’s vegetation dynamics are crucial for its regional water–heat balance and ecosystem functioning. Leaf Area Index (LAI) serves as a key indicator bridging canopy architecture and plant physiological activities. Existing studies have made significant advancements in simulating LAI, yet accurate LAI simulation remains challenging. To address this challenge and gain deeper insights into the environmental controls of LAI, this study aims to accurately simulate LAI in the Loess Plateau using deep learning models and to elucidate the spatiotemporal influence of soil moisture and temperature on LAI dynamics. For this purpose, we used three deep learning models, namely Artificial Neural Network (ANN), Long Short-Term Memory (LSTM), and Interpretable Multivariable (IMV)-LSTM, to simulate LAI in the Loess Plateau, only using soil moisture and temperature as inputs. Results indicated that our approach outperformed traditional models and effectively captured LAI variations across different vegetation types. The attention analysis revealed that soil moisture mainly influenced LAI in the arid northwest and temperature was the predominant effect in the humid southeast. Seasonally, soil moisture was crucial in spring and summer, notably in grasslands and croplands, whereas temperature dominated in autumn and winter. Notably, forests had the longest temperature-sensitive periods. As LAI increased, soil moisture became more influential, and at peak LAI, both factors exerted varying controls on different vegetation types. These findings demonstrated the strength of deep learning for simulating vegetation–climate interactions and provided insights into hydrothermal regulation mechanisms in semiarid regions.
Sérgio da Costa Dias, Andressa Lima de Brida, Maguintontz Cedney Jean-Baptiste
et al.
The spotted-wing drosophila, <i>Drosophila suzukii</i> (Matsumura) (Diptera: Drosophilidae), is a pest that reduces the productivity of small fruits. Entomopathogenic nematodes (EPNs) and chemical insecticides can suppress this pest, but the compatibility of the two approaches together requires further examination. This laboratory study evaluated the compatibility of <i>Steinernema brazilense</i> IBCBn 06, <i>S. carpocapsae</i> IBCBn 02, <i>Heterorhabditis amazonensis</i> IBCBn 24, and <i>H. bacteriophora</i> HB with ten chemical insecticides registered for managing <i>D. suzukii</i> pupae. In the first study, most insecticides at the recommended rate did not reduce the viability (% of living infective juveniles (IJs)) of <i>S. braziliense</i> and both <i>Heterorhabditis</i> species. The viability of <i>S. carpocapsae</i> was lowered by exposure to spinetoram, malathion, abamectin, azadirachtin, deltamethrin, lambda-cyhalothrin, malathion, and spinetoram after 48 h. During infectivity bioassays, phosmet was compatible with all the EPNs, causing minimal changes in infectivity (% pupal mortality) and efficiency relative to EPN-only controls, whereas lambda-cyhalothrin generally reduced infectivity of EPNs on <i>D. suzukii</i> pupae the most, with a 53, 75, 57, and 13% reduction in infectivity efficiency among <i>H. bacteriophora, H. amazonensis, S. carpocapsae</i>, and <i>S. brazilense</i>, respectively. The second study compared pupal mortality caused by the two most compatible nematode species and five insecticides in various combinations. Both <i>Heterorhabditis</i> species caused 78–79% mortality among <i>D. suzukii</i> pupae when used alone, and were tested in combination with spinetoram, malathion, azadirachtin, phosmet, or novaluron at a one-quarter rate. Notably, <i>H. bacteriophora</i> caused 79% mortality on <i>D. suzukii</i> pupae when used alone, and 89% mortality when combined with spinetoram, showing an additive effect. Novaluron drastically reduced the number of progeny IJs when combined with <i>H. amazonensis</i> by 270 IJs and <i>H. bacteriophora</i> by 218. Any adult flies that emerged from EPN–insecticide-treated pupae had a shorter lifespan than from untreated pupae. The combined use of <i>Heterorhabditis</i> and compatible chemical insecticides was promising, except for novaluron.
Societal Impact Statement Conserving frankincense trees (Boswellia) is crucial for both ecological and socio‐economic reasons. Surveying these trees in the field and using remote sensing unmanned aerial vehicles in the Socotra Archipelago, we found that Socotran frankincense trees are threatened by forest fragmentation, overgrazing, and increasingly frequent extreme climate events. A better understanding of the distribution and the threats of these important insular species will improve the conservation policy of the local authorities and benefit local communities in the Socotra Archipelago. At the same time, this work serves as a good practice example to guide conservation efforts for other culturally important threatened tree species around the world, therefore helping to sustain local livelihoods, fostering ecological resilience, and supporting socio‐economic stability. Summary Globally, frankincense trees (Burseraceae: Boswellia) are increasingly under threat because of habitat deterioration, climate impacts, and the olibanum trade. Despite harboring nearly half of the species in the genus, up‐to‐date insights are lacking for the insular endemic frankincense trees of the Socotra Archipelago UNESCO (United Nations Educational, Scientific and Cultural Organization) World Heritage Site (Yemen). We combined georeferencing of individual trees in the field with remote sensing applying unmanned aerial vehicles (UAVs) to evaluate Boswellia distribution and (sub)population sizes in the entire Socotra Archipelago. We counted 17,253 trees across all 11 taxa and we surveyed almost 55% directly in the field, collecting individual information on threats and health indicators. We estimate that the current total population sizes of the relatively common Socotran Boswellia taxa (Boswellia elongata, Boswellia popoviana, and Boswellia ameero) consist of a few thousand mature individuals with fragmented distribution of which a large proportion occurs in highly disjunct relictual stands, while the more range‐restricted species survive only through a few hundred (Boswellia nana and Boswellia samhaensis) to fewer than a hundred trees (Boswellia scopulorum). Our field data show that the Socotran frankincense trees are threatened by fragmentation and overgrazing resulting in a lack of natural regeneration, in combination with effects of extreme climate events (e.g., higher frequency and intensity of cyclones and prolonged drought) and potential future infrastructure developments; the species are less impacted by resin collection. We provide recommendations to strategize urgent protection of the declining Socotran frankincense trees, and we update their conservation status, resulting in an endangered status for seven and a critically endangered status for four taxa.
Valencia V. Ndlangamandla, Adeola Salawu-Rotimi, Vuyiswa S. Bushula-Njah
et al.
<i>Cannabis sativa</i> L. is a monotypic genus belonging to the family Cannabaceae. It is one of the oldest species cultivated by humans, believed to have originated in Central Asia. In pivotal judgements in 2016 and 2018, the South African Constitutional Court legalised the use of <i>Cannabis</i> within the country for medicinal and recreational purposes, respectively. These decrees opened opportunities for in-depth research where previously there had been varying sentiments for research to be conducted on the plant. This review seeks to examine the history, genetic diversity, and chemical profile of <i>Cannabis</i>. The cultivation of <i>Cannabis</i> by indigenous people of southern Africa dates back to the eighteenth century. Indigenous rural communities have been supporting their livelihoods through <i>Cannabis</i> farming even before its legalisation. However, there are limited studies on the plant’s diversity, both morphologically and genetically, and its chemical composition. Also, there is a lack of proper documentation of <i>Cannabis</i> varieties in southern Africa. Currently, the National Centre for Biotechnology Information (NCBI) has 15 genome assemblies of <i>Cannabis</i> obtained from hemp and drug cultivars; however, none of these are representatives of African samples. More studies are needed to explore the species’ knowledge gaps on genetic diversity and chemical profiles to develop the <i>Cannabis</i> sector in southern Africa.
Jeffrey J. Jones, Christopher Shaw, Tsu‐Wei Chen
et al.
Societal Impact Statement Refining circular multitrophic food production methods, which integrate plant, fish, and insect outputs, is imperative for environmental sustainability. Our findings suggest that the right protein choices in fish feed, like black soldier fly meal and poultry meal, can notably enhance the nutrient profile of fish waste water. This, in turn, is conducive for hydroponic cultivation, enhancing the nutritional attributes of plants like basil and lettuce. As we reduce environmental impact and optimize resource use, it is evident that our food ecosystems are deeply intertwined. Harnessing these synergies could redefine our approach to food production, paving the way for a more sustainable global future. Summary Optimization of nutrient use efficiencies in circular multitrophic food production systems (i.e., plant, fish, and insect production) is crucial for sustainability. This study tested how protein ingredient choice in fish feed influences the plant nutritional value of the fish waste water when used for hydroponic crop production. Waste water samples were obtained from recirculating aquaculture systems (RAS) in which Nile tilapia (Oreochromis niloticus) were fed different single protein source diets—black soldier fly meal (BSFM), poultry by‐product meal (PM), poultry blood meal (PBM), and fish meal. Water was analyzed for plant nutrients and used for lettuce and basil cultivation to evaluate their suitability for hydroponic crop production—viz. yield, mineral nutrient, and selected secondary metabolite levels. BSFM RAS water had the highest concentrations of K, Mg, and micronutrients (Cu, Mn, Mo, Zn) of the RAS waters, whereas PM RAS water contained the highest P concentration and had a mean pH of 6.5 closer to the optimum pH for hydroponic plants. These RAS waters consequently lead to the highest yields in basil and lettuce indicating the importance of the aforementioned factors. From a plant production perspective, BSFM appears promising as a protein source in fish feeds for aquaponics. Usage of RAS waters for plant production helps reduce (i) environmental impact of RAS water and (ii) resource input in plant production. Longer term RAS trials should be conducted to determine the maximum nutrient concentrations achievable during fish production with diets including BSFM as the main protein source.
Ginseng has been well-known as a medicinal plant for thousands of years. Bacterial endophytes ubiquitously colonize the inside tissues of ginseng without any disease symptoms. The identification of bacterial endophytes is conducted through either the internal transcribed spacer region combined with ribosomal sequences or metagenomics. Bacterial endophyte communities differ in their diversity and composition profile, depending on the geographical location, cultivation condition, and tissue, age, and species of ginseng. Bacterial endophytes have a significant effect on the growth of ginseng through indole-3-acetic acid (IAA) and siderophore production, phosphate solubilization, and nitrogen fixation. Moreover, bacterial endophytes can protect ginseng by acting as biocontrol agents. Interestingly, bacterial endophytes isolated from Panax species have the potential to produce ginsenosides and bioactive metabolites, which can be used in the production of food and medicine. The ability of bacterial endophytes to transform major ginsenosides into minor ginsenosides using β-glucosidase is gaining increasing attention as a promising biotechnology. Recently, metabolic engineering has accelerated the possibilities for potential applications of bacterial endophytes in producing beneficial secondary metabolites.
Ricardo Díaz-Delgado, Gábor Ónodi, György Kröel-Dulay
et al.
Although many climate research experiments are providing valuable data, long-term measurements are not always affordable. In the last decades, several facilities have secured long-term experiments, but few studies have incorporated spatial and scale effects. Most of them have been implemented in experimental agricultural fields but none for ecological studies. Scale effects can be assessed using remote sensing images from space or airborne platforms. Unmanned aerial vehicles (UAVs) are contributing to an increased spatial resolution, as well as becoming the intermediate scale between ground measurements and satellite/airborne image data. In this paper we assess the applicability of UAV-borne multispectral images to provide complementary experimental data collected at point scale (field sampling) in a long-term rain manipulation experiment located at the Kiskun Long-Term Socio-Ecological Research (LTSER) site named ExDRain to assess the effects on grassland vegetation. Two multispectral sensors were compared at different scales, the Parrot Sequoia camera on board a UAV and the portable Cropscan spectroradiometer. The NDVI values were used to assess the effect of plastic roofs and a proportional reduction effect was found for Sequoia-derived NDVI values. Acceptable and significant positive relationships were found between both sensors at different scales, being stronger at Cropscan measurement scale. Differences found at plot scale might be due to heterogeneous responses to treatments. Spatial variability analysis pointed out a more homogeneous response for plots submitted to severe and moderate drought. More investigation is needed to address the possible effect of species abundance on NDVI at plot scale contributing to a more consistent representation of ground measurements. The feasibility of carrying out systematic UAV flights coincident or close to ground campaigns will certainly reveal the consistency of the observed spatial patterns in the long run.