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Simple Summary: Chromaphis juglandicola is a serious insect pest of walnut trees. Harmonia axyridis and Coccinella septempunctata are ladybird species that are important predators of C. juglandicola. This study aimed to determine the effects of extraguild prey density and temperature on intraguild predation (IGP) between two ladybird species. The results showed that IGP increased with increasing temperature (15–35 °C) and decreasing extraguild prey density. The number of extraguild prey consumed by C. septempunctata or H. axyridis increased with increasing temperature. These results provide a scientific basis for the rational use of H. axyridis and C. septempunctata to control small walnut aphids. The ladybirds Coccinella septempunctata and Harmonia axyridis are important biocontrol agents for the small walnut aphid Chromaphis juglandicola, a key walnut pest. C. juglandicola outbreaks occur in walnut orchards, and walnut yields have declined. Intraguild predation (IGP) is prevalent among natural enemies that coexist in shared habitats and prey upon the same extraguild prey. We designed laboratory experiments to evaluate the potential for IGP between these two ladybirds at different temperatures and extraguild (EG) prey densities, and the ability of IGP to control EG prey under different conditions. We measured IGP rates in first instar larvae, female adults, and male adults (both starved for 24 h) in the vulnerable immature life stages of two ladybird eggs. Intraguild (IG) prey (H. axyridis eggs or C. septempunctata eggs) and EG prey (C. juglandicola) consumption were tallied after 24 h. Temperature and EG prey density influenced IGP rates, with temperature contributing the most to the variance. IGP increased with increasing temperature (15–35 °C), with both factors interactively influencing the EG prey consumption rate and exhibiting highly significant effects. EG prey consumption increased with temperature and density. This research provides theoretical support for the rational use of H. axyridis and C. septempunctata in the joint biological control of C. juglandicola [ABSTRACT FROM AUTHOR]

As global biodiversity hotspots, wild fruit forests play key ecological functions, providing essential ecosystem services such as carbon storage, soil retention, and water conservation, and support food chains and biodiversity conservation through key species. Climate change, with rising temperatures and altered precipitation patterns, threatens wild fruit forests by reducing the habitats and numbers of key species, potentially turning these ecosystems from carbon sinks to sources and diminishing overall biodiversity and ecosystem services. However, research on how these changes affect important species' habitats and carbon dynamics remains insufficient. To address this, we analysed habitat suitability for three important species (Prunus armeniaca L., Malus sieversii, and Prunus ledebouriana (Schltdl.) Y.Y.Yao with the aim of informing conservation strategies. We used biomod2 to integrate environmental and species data using six methods, encompassing 12 models. We predicted overlapping geographical distributions of three species, analysing their ecological niches and environmental interactions using global datasets to understand their adaptations. This analysis revealed ecological niche shifts and reductions in resource utilisation in both current and future scenarios. Their distribution centres will move poleward under the influence of bioclimatic factors and human activities. In conclusion, protecting P. armeniaca, M. sieversii, and P. ledebouriana is essential for the conservation and overall health of wild fruit forest ecosystems. This study provides new insights into climate change, habitat loss, informing conservation and resilience strategies. [ABSTRACT FROM AUTHOR]

As an important ecosystem, the wild fruit forest in the Tianshan Mountains is one of the origins of many fruit trees in the world. The wild fruit forest in Emin County, Xinjiang, China, was taken as the research area, the spatial and temporal distribution of the wild fruit forest was inverted using random forest and PLUS models, and the 2027 distribution pattern of the wild fruit forest was simulated and predicted. From 2007 to 2013, damage to the wild fruit forest from tourism and overgrazing was very serious, and the area occupied by the wild fruit forest decreased rapidly from 9.59 km2 to 7.66 km2. From 2013 to 2020, suitable temperatures and reasonable tourism management provided strong conditions for the rejuvenation of wild fruit forests. The distance of the center of gravity of the wild fruit forest increased, and the density of distribution of the wild fruit forest in the northwest direction of the study area also increased. It is predicted that the wild fruit forest in the study area will show a steady and slowly increasing trend in places far away from tourist areas and with more complex terrain. It is suggested that non-permanent fences be set up as buffer zones between wild fruit forests, ensuring basic maintenance of wild fruit forests, limiting human disturbance such as overgrazing, and reducing the risk of soil erosion. [ABSTRACT FROM AUTHOR]

Evaluating quality traits is important to the selection of elite lines in Brassica napus L. In this study, the quality traits of 488 global collections of B. napus L were evaluated for two consecutive years under central Chinese growing conditions, and a series of phenotypic data was obtained. The measured total glucosinolate content (GLC) and erucic acid content (ERU) values for 95.5% of the accessions were consistent with the original values, and large variations in quality traits were found among these accessions, thus enabling selection for these characters. In general, Chinese accessions tended to have a higher oil content (OC) than foreign accessions, while compared with winter and spring accessions, semi-winter accessions tended to have the highest OC. The mean GLC and ERU of Chinese rapeseed accessions showed gradual downward trends over time, and the genotypic variation in ERU accounted for 98.44% of the total variation, which was the highest among all 10 of the quality traits. Additionally, the heritability for ERU was largest among all 10 of the quality traits. Significant correlations were observed between different traits; OC had significantly (P < 0.01) negative correlation coefficients with oleic acid content, whereas OC had significantly (P < 0.01) positive correlation coefficients with ERU. Principal component analysis revealed that there was no clear boundary among materials of different geographic origins and different ecotypes according to the first two principal coordinates, respectively. This information about variations in quality traits revealed in this study could identify parents for improved rapeseed breeding. [ABSTRACT FROM AUTHOR]