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What are the main findings? An efficient monitoring model integrating UAV hyperspectral imagery and machine learning was developed for detecting walnut leaf scorch. The Genetic Algorithm-optimized SVM model (GA-SVM) achieved the highest predictive performance (R[sup.2] = 0.6302, RMSE = 0.0629, MAE = 0.0480). What are the implications of the main findings? Offers a rapid and precise tool for the detection and precision management of walnut leaf scorch. The UAV-based approach enables site-specific disease detection, improves monitoring efficiency, and reduces reliance on costly manual ground surveys. Walnut (Juglans regia L.), a critical economic species, experiences substantial declines in fruit quality and yield due to Walnut Leaf Scorch (WLS). This issue is particularly severe in the Xinjiang Uygur Autonomous Region (XUAR)—one of Asia’s leading walnut-producing regions. To mitigate the disease, timely and efficient monitoring approaches for detecting infected trees and quantifying their disease severity are in urgent demand. In this study, we explored the feasibility of developing a predictive model for the precise quantification of WLS severity. First, five 4-mu (1 mu = 0.067 ha) sample plots were established to identify infected individual trees, from which the WLS Disease Index (DI) was calculated for each tree. Concurrently, hyperspectral data of individual trees were acquired via an unmanned aerial vehicle (UAV) platform. Second, DI estimation models were developed based on the Random Forest (RF) and Support Vector Machine (SVM) algorithms, with each algorithm optimized using either Grid Search (GS) or a Genetic Algorithm (GA). Finally, four integrated models (GS-RF, GA-RF, GS-SVM, and GA-SVM) were constructed and systematically compared. The results showed that the Genetic Algorithm-optimized SVM model (GA-SVM) exhibited the highest predictive accuracy and robustness, achieving a coefficient of determination (R[sup.2]) of 0.6302, a Root Mean Square Error (RMSE) of 0.0629, and a Mean Absolute Error (MAE) of 0.0480. Our findings demonstrate the great potential of integrating UAV-based hyperspectral remote sensing with optimized machine learning algorithms for WLS monitoring, thus offering a novel technical approach for the macroscopic, rapid, and non-destructive surveillance of this disease.

Juglans leaf necrosis (JLN) is a physiological disease primarily associated with abiotic stressors such as high temperatures, drought, and soil salinity, though biotic factors may also exacerbate its severity. It is a global concern affecting walnut production in multiple regions, including Xinjiang, China. In recent years, climate change, shifting agricultural practices, and disease transmission have increased its incidence, severely affecting tree growth, yield, and quality. Traditional field-based monitoring is labor-intensive and often inaccurate, underscoring the need for advanced remote sensing. To provide fast and objective monitoring, we used hyperspectral and high-resolution RGB imagery acquired by an unmanned aerial vehicle (UAV) to track JLN from June to September 2024 in southern Xinjiang. Five survey rounds captured the progression of disease severity. Among 17 vegetation indices, the modified red edge simple ratio (MRESRI), carotenoid reflectance index 1 (CRI1), and photochemical reflectance index (PRI) were the most informative for severity mapping. A Random Forest classifier achieved 86% overall accuracy and a Cohen’s kappa of 0.825. Spatial patterns showed persistent hotspots in low-lying areas, near roads, and in dense stands. These findings provide an effective, scalable approach for early detection and severity assessment, enabling timely, targeted interventions. Adoption of UAV-based hyperspectral monitoring can improve field surveillance, optimize resource allocation, and support sustainable walnut production.

This study used Xinxin 2 (Juglans regia L. ‘Xinxin2’), a major cultivated walnut variety in Xinjiang, China, to clarify the response and adaptation mechanisms of the anatomical structures of walnut related to source–sink–flow under altered source–sink relationships. We anatomically observed the leaves, fruit stalks, and fruit of bearing branches by artificially adjusting the leaf-to-fruit ratio (LFR). The LFR substantially affected the leaf structure and thickness of the fruit-bearing branches obtained via girdled (p < 0.05). The results of the analysis of the leaf anatomy revealed that a low LFR impeded leaf growth and internal structural development while accelerating senescence, whereas a high LFR promoted leaf growth and delayed senescence. The same trend was observed for the phloem area (PA) of the fruit stalk with the increase in fruit load when the number of leaves on the fruit branch was the same. The maximum PA was reached when the number of fruits was high (except for 4L:3F). This indicates that the micro-anatomical structure of the fruit stalk is more developed under the treatment of a higher number of pinnate compound leaves and fruit level of LFRs. The cells of the 1L:3F and 2L:3F were considerably smaller in the green peel and kernel of the fruit on the branches obtained via girdled than those of 5L:1F plants (p < 0.05). No significant difference was found in the number of cells per unit area or the cross-sectional area of cells in the pericarp and kernel of the fruit under LFRs (p > 0.05); however, a large difference was noted in the microanatomical structure of the pericarp and kernel of fruit. Changes in the structural adaptation characteristics of walnut leaves (source), fruit stalk (flow), and fruit (sink) are related to source–sink regulation. A change in the LFR affects the carbohydrate synthesis in the leaves (source), transport in fruit stalks (flow), and the carbohydrate reception in fruits (sink).

Spodoptera frugiperda (J.E. Smith) is a crucial agricultural pest owing to its global impact on >300 crops. Among these, the corn strain of S. frugiperda causes significant damage to maize (Zea mays L.). However, limited research exists on the influence of maize nutrients on the metamorphosis of S. frugiperda and the underlying mechanisms. In this study, the effects of different growth stages of maize leaves, namely, tender leaves (tender) and mature leaves (mature), on various aspects of larval development, including body weight, body length, developmental age, pupation rate, and eclosion rate, were investigated. Additionally, we measured the levels of 20-hydroxyecdysone (20E) and three types of juvenile hormone (JH; i.e., JH I–III) in S. frugiperda larvae fed on tender or mature. The results revealed that larvae fed on Tender exhibited significantly prolonged instar duration, reduced body weight and length, and decreased pupation and eclosion rates, with the emergence of abnormal adults. Analysis of nutritional components in maize leaves revealed significantly higher levels of amino acids, soluble sugars, and sterols in mature than in tender. Hormone analysis in S. frugiperda larvae revealed higher 20E titers in individuals feeding on mature during prepupal and pupal stages. We demonstrated the crucial role of sterols in regulating the level of 20E and pupation rate of S. frugiperda. Based on these findings, we propose that isoleucine, arginine, glutamic acid, sucrose, campesterol, and β-sitosterol serve as key nutrients influencing the development of S. frugiperda. Moreover, β-sitosterol is a significant factor influencing the interaction between maize leaves and S. frugiperda. Our research results provide a reference for the control strategy of S. frugiperda based on breeding insect-resistant varieties by altering host nutrition.

Korla fragrant pear is a high-quality local pear variety native to Xinjiang, China. Currently, the low fruit-setting rate and low calyx shedding rate problems in Korla fragrant pears have been highlighted, which seriously affect the fruit yield and quality. It is of great significance to research the fruiting characteristics and molecular-assisted identification of Korla fragrant pear bud mutation materials for enriching the germplasm resources of Korla fragrant pear. In this research, a natural pollination group (YB) of Korla fragrant pear bud mutation materials and a natural pollination group (CK) of Korla fragrant pears were established. On the fruiting characteristics, the fruit-setting rate and calyx-removal rate of the two groups were investigated. In terms of fruit quality, the fruit shape index, fruit specific gravity, soluble solids content, sugar:acid ratio, soluble sugar content, and other indicators were measured. For the anatomical structure of the calyx tube, the detachment cells were observed. The formation time of the two groups of detached cells was compared. In the GBS simplified genome sequencing, a phylogenetic tree was constructed based on the obtained SNP sites. A principal component analysis, population genetic structure analysis, and genetic diversity index analysis were carried out. In the aspect of SSR molecular marker identification, the SSR types were counted. Polyacrylamide gel electrophoresis was performed. The results demonstrate the following: (1) the fruit-setting rate (30.87%) and calyx-removal rate (68.11%) in the YB group were significantly higher than those in the CK group (19.37%) and the calyx-removal rate (55.18%). (2) There was no significant difference in fruit quality indexes, such as average fruit weight (127.10–130.00 g) and soluble sugar content (9.47–9.56%) between the two groups. (3) Abscission-layer cells were observed at 2, 4, 6, 8, and 10 h after calyx tube discoloration in the YB group and at 48, 72, and 96 h after calyx tube discoloration in the CK group. (4) The genetic background of the YB group and the CK group was similar at the GBS level, but there were differences at the DNA level. This research finally shows that Korla fragrant pear bud mutation material is a good germplasm resource. This germplasm resource can promote the structural optimization of Korla fragrant pear varieties and the healthy development of the industry.

Whether the calyx tube of the Korla fragrant pear falls off seriously affects the fruit quality. ‘Xinnonglinxiang’ is a mutant variety of the Korla fragrant pear, which has a high calyx removal rate under natural conditions, and calyx tube fall seriously affects the fruit quality. The mechanism behind the high calyx removal rate of ‘Xinnonglinxiang’ remains unclear; thus, Korla fragrant pear (PT) and ‘Xinnonglinxiang’ (YB) with different degrees of calyx abscission were used as examples and the abscission areas of calyx tubes were collected in the early (21 April), middle (23 April), and late (25 April) shedding stages to explore the regulatory mechanism behind the abscission. The combination of the results of physiological, cytological, and transcriptomic methods indicated the highest number of differentially expressed genes (DEGs) in the middle of shedding. GO (Gene Ontology) enrichment analysis showed that the expression levels of genes related to the CEL (cellulase) and PG (polygalacturonase) activity functional pathways differed significantly in the two varieties during the three periods, whereas Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the DEGs were significantly concentrated in the plant hormone signal transduction pathway in all three periods. The expression levels of genes related to the plant hormone signal transduction pathway differed significantly for the two varieties during calyx shedding. Five gene modules were obtained using Weighted Gene Co-Expression Network Analysis (WGCNA), and transcriptome data were correlated with five physiological index values. Two key modules that highly correlated with the Eth (ethylene) response were then screened, and 20 core genes were identified, with IRX10, IRX9, and OXI1 likely the hub genes that are involved in the regulation of calyx shedding in the YB variety. The obtained results provide reliable data for the screening of candidate genes for calyx shedding and analysis of the regulatory mechanism behind a high calyx shedding rate, providing a theoretical basis upon which the calyx shedding rate of fruits can be improved through genetic improvement.

The study focused on the relationship between leaf-to-fruit ratio (LFR) and walnut kernel quality in Juglans regia ‘Wen 185’. It was investigated how LFR influences single kernel weight, the contents and percentages of organic matter in kernels, the 13C distribution proportion (13CDP) in crude fat and protein, and the number and size of oil bodies within the kernels. A gradually decreasing LFR led to reduced single kernel weight, the contents of crude fat, crude protein, and soluble sugar dramatically (P < 0.05), with no significant changes in the percentages and (13CDP) of crude fat, crude protein, and soluble sugar (P > 0.05). Moreover, there were no significant differences in the number of oil bodies per unit area and the size of oil bodies in kernel cotyledons and endosperm storage cells among the different LFR (P > 0.05). We propose that the walnut kernel quality depends on the proportion of sugar converted into fat and protein in the kernels, that the changes in LFR affect the amount of sugar accumulated in kernels but not the proportion of sugar converted to fat and protein, and that the LFR, therefore, have no effect on the percentages of crude fat and crude protein in walnut kernels.

Functional analysis was performed to elucidate the mechanism by which hepatocellular carcinoma (HCC) outcome-associated mutation in the hepatitis B virus X ( ) gene modifies the HCC process. Proliferation, invasion, migration, and apoptosis assays were performed, and changes in fibrosis, intracellular reactive oxygen species (ROS), and cytokine levels were measured. The differences between variables were evaluated by Student's -test. The influence of two previously identified nonsynonymous mutation, C1653T and T1753C, on HCC cells was assessed. With regard to HBX-induced promotion of proliferation (p < 0.01), invasion (p < 0.01) and migration (p < 0.01), the C1653T mutation displayed a significant additive effect in these assays (P < 0.05). The subsequent apoptosis assay indicated that HBX could inhibit apoptosis (P < 0.01), whereas the C1653T mutation markedly amplified this effect in HCC cells (P < 0.01). Furthermore, the tumor growth-promoting effect of HBX was confirmed in a mouse xenograft model of HCC (P < 0.05), and the C1653T mutation was observed to amplify this effect (P < 0.05). To further investigate the mechanism by which the C1653T mutation enhances malignancy in HCC cells, fibrosis, intracellular ROS, and cytokine levels were measured. The C1653T mutant increased fibrosis and intracellular ROS level, and altered monocyte chemotactic protein-1 and interleukin-18 expression in HepG2 cells. Drug sensitivity test revealed that the C1653T mutation is sensitive to apatinib treatment and that overexpression of vascular endothelial growth factor might be involved in this process. Our data indicate that the C1653T mutation of promotes HCC malignancy by altering the levels of fibrosis, ROS, and some cytokines. This mutation could serve as a potential biomarker for screening HCC patients to determine apatinib treatment efficacy.

Pro-angiogenic factors are key regulators of angiogenesis. Here we report that highly migratory cells patrol the area of capillary formation in chick embryo chorioallantoic membrane. These cells deposit migrasomes on their migration tracks, creating migrasome-enriched areas. Single-cell sequencing identified these cells as monocytes. Depletion of monocytes impairs capillary formation. Quantitative mass spectrometry analysis reveals that monocyte migrasomes are enriched with pro-angiogenic factors. Purified migrasomes promote capillary formation and monocyte recruitment in vivo, and endothelial cell tube formation and monocyte chemotaxis in vitro. Knockdown or knockout of TSPAN4 reduces migrasome formation and impairs capillary formation and monocyte recruitment. Mechanistically, monocytes promote angiogenesis via VEGFA and CXCL12 in migrasomes. In summary, monocytes deposit migrasomes enriched in pro-angiogenic factors to promote angiogenesis. Zhang et al. have data suggesting that, in the chicken embryo, monocytes foster a pro-angiogenic microenvironment in advance of angiogenesis by depositing migrasomes enriched in angiogenic factors.