Grape phylloxera, Daktulosphaira vitifoliae, is a small, invasive, sap-sucking pest that is widely present in most viticulture regions all over the world. It is originally from North America and feeds on grapevine roots and leaves. In the current study, the potential distribution area of the leaf-feeding population was investigated with MaxEnt based on population occurrence data under different environmental variables. Results suggested that under current climatic conditions, Europe, East and North China, Japan, the Eastern USA, Uruguay, and the Southeast of South America are highly suitable areas for the occurrence of phylloxera leaf populations. The results showed that isothermality and precipitation of coldest quarter were major factors which contribute more than 60% of the model under current climate conditions. Our results provide important information for governmental decision makers and famers to develop control and management strategies against D. vitifoliae, and can also be used as a reference for studies on other invasive pest.

Grapes are cultivated worldwide and have a high economic value as fruit trees. However, winter frost damage and spring cold damage have limited the sustainability of the table grape industry. A novel plant growth regulator, 24-epibrassinolide (EBR), exhibits an essential regulatory function in plant life cycles, especially in its unique mechanism against various environmental stresses. We treated ‘Lihongbao’ grapes with exogenous EBR (0.2 μM), brassinazole (BRZ, 10 μM), EBR + BRZ (0.2 μM +10 μM), and deionized water (CK). We investigated the effect of exogenous EBR on ‘Lihongbao’ grape seedlings under low-temperature stress (4°C) at different periods (0 h, 12 h, 24 h, 48 h, and 96 h). We explored physiological mitigation mechanisms of exogenous EBR in grape seedlings with low-temperature injury by observing the impacts of EBR treatment on the physical and biochemical indices such as phenotypes and anatomical structures, photosynthetic characteristics, chlorophyll fluorescence parameters, antioxidant systems, and osmoregulatory substances. Exogenous EBR had an inhibitory effect on cold stress in grape seedlings at different treatment periods compared with the CK group. Based on plant phenotype and anatomical structure, the leaves of the grape seedlings treated with exogenous EBR showed no signs of water loss or wilting. At 96 h under low-temperature stress, the lower epidermal thickness (LET), palisade tissue thickness (PT), palisade-to-sea ratio (P/S), and blade structural compactness (CTR) of the exogenous EBR-treated grape leaves were significantly reduced by 6.71%, 19.59%, 14.52%, and 11.65% compared with the CK group, respectively. Chlorophyll a (Chl a), chlorophyll b (Chl b), total chlorophyll (Chl total), carotenoids (carotenoid), transpiration rate (Tr), and stomatal conductance (Gs) contents of exogenous EBR-treated grape leaves were significantly upregulated by 30.24%, 48.52%, 39.75%, 34.67%, 704.66%, and 277.27%, respectively. The intercellular CO₂ concentration (Ci) and non-photosynthetic burst coefficient (NPQ) of exogenous EBR-treated grape leaves were significantly downregulated by 16.29% and 25.83%, respectively. Glutathione (GSH) contents of exogenous EBR-treated grape leaves were significantly upregulated by 33.63%, superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX) activities of exogenous EBR-treated grape leaves were significantly increased by 42.70%, 27.60%, and 28.64%, respectively. However, hydrogen peroxide (H₂O₂), superoxide anion (O₂·⁻), and malondialdehyde (MDA) contents of exogenous EBR-treated grape leaves were reduced by 29.88%, 23.66%, and 47.96%, respectively, and significantly. Catalase (CAT) activity of exogenous EBR-treated grape leaves significantly increased by 15.03%. Soluble sugar and free proline contents increased by 5.29% and 19.44%, respectively, and significantly. Exogenous EBR could effectively alleviate growth inhibition caused by regulating the antioxidant system indices in grape seedlings under cold temperature. The results offer a theoretical basis for enhancing grape cold tolerance.

Wheat (Triticum aestivum L.) is a globally important staple crop; however, its growth and yield are severely limited by drought stress. This study evaluated the effects of a combined microbial inoculant, Streptomyces pactum Act12 and Streptomyces rochei D74, on wheat photosynthesis, physiological traits, and yield under drought conditions. Key physiological and yield parameters were measured during the jointing, heading, and grain-filling stages. Drought stress significantly reduced chlorophyll content, maximum photochemical efficiency of photosystem II (PSII) (Fv/Fm), and antioxidant enzyme activities, while increasing malondialdehyde (MDA) levels, leading to a notable yield decline. In contrast, inoculation with Streptomyces strains alleviated these adverse effects, with the combined inoculant (Act12+D74) group demonstrating the most significant improvement. Chlorophyll content increased by up to 32.60%, Fv/Fm improved by 43.07%, and antioxidant enzyme activities were enhanced, with superoxide dismutase (SOD) activity increasing by 19.32% and peroxidase (POD) activity by 75.44%. Meanwhile, MDA levels were reduced by 61.61%. The proline content in the combined inoculant group increased by 90.44% at the jointing stage and the soluble protein content increased by 60.17% at the heading stage. Furthermore, it improved the yield by 26.19% by increasing both effective spikes and grains per spike. For the first time, this study revealed the synergistic effects of Act12 and D74 in enhancing photosynthesis, strengthening antioxidant defenses, and optimizing osmotic regulation under drought conditions. These findings provide a theoretical basis for developing environmentally friendly drought management strategies and highlight the potential applications of this inoculant in sustainable agriculture.