Plants

Phytophthora root and stem infection by Phytophthora sojae is a global and devastating disease of soybeans. Selecting disease-resistant varieties is the most economical and effective measure for controlling this disease. Delving into the disease resistance and defense molecular mechanisms can lay a theoretical foundation for solving this problem. Here, we screened the soybean genome and identified 78 GmDof genes distributed on nineteen chromosomes. Subcellular localization analysis revealed that the majority of GmDof proteins were located in the cell nucleus. Phylogenetic analysis categorized these genes into nine subfamilies. Gene structure analysis showed that all GmDofs contained 0 to 2 introns, and most of them did not have introns. Motif and conserved domain analysis showed that all GmDofs contained a common motif (motif-1) and a typical conserved C₂-C₂ domain. The prediction of cis-acting elements in promoter regions revealed numerous cis-regulatory elements responsible for stress responses, plant growth and development, plant hormone responses, and light responses. RNA-seq and quantitative real-time PCR results showed that GmDof63 (Glyma.16G145000) was specifically expressed at high levels after P. sojae infection. GmDof63 was strongly induced by SA and ETH treatments. The soybean seedlings overexpressing GmDof63 displayed enhanced resistance to P. sojae infection compared with the wild-type soybean seedlings. Further experiments indicated that the expression levels of pathogenesis-related protein genes PR1a, PR4, PR5a, and PR10 were significantly up-regulated in GmDof63-overexpressing transgenic soybean seedlings. Taken together, these findings reveal the mechanism by which GmDof63 directly or indirectly regulates the expression of PR genes to modulate the soybean response to P. sojae infection.

Calotropis procera, known as “Silk cotton”, stands out for the presence of various classes of bioactive compounds responsible for its ethnopharmacological properties. The study aimed to conduct a phytochemical investigation, evaluating the in vitro and in vivo toxicity together with the antinociceptive potential of an n-butanolic fraction (FB) from the leaves. The crude ethanolic extract (CEE) was obtained by maceration in ethanol for 72 h. It was then partitioned using a gradual solvent sequence. The FB was analyzed by HPLC-ESI-MS/MS in negative mode and ¹H and ¹³C NMR. Toxicity was assessed by the erythrocyte hemolytic assay and acute oral toxicity test at a single dose of 300 mg·kg⁻¹. The antinociceptive effect was assessed by the acetic acid-induced abdominal writhing test and the formalin test in mice at doses of 3.75, 7.5 and 15 mg·kg⁻¹ per os. HPLC-ESI-MS/MS analysis identified flavonoids, phenolic acids, and the megastigmane roseoside, isolated for the first time in C. procera. The FB did not cause hemolytic effects or behavioral or physiological changes in mice. It showed an antinociceptive effect at all doses, reducing abdominal writhing by up to 91.46% and the licking time in phases 1 and 2 of the formalin test by up to 63.83% and 91.73%, respectively. In this study, it was possible to determine that an FB of a crude extract of C. procera leaves has antinociceptive activity, possibly associated with the phenolic compounds and roseoside found, with a lack of toxicity in vitro and in vivo, validating its ethnopharmacological use.

Boron exerts regulatory control over various aspects of plant growth and morphogenesis, and the application of boron prior to anthesis has been recognized as a critical agronomic practice. However, the regulatory mechanisms by which boron influences fruit set and early ovary development in pear remain to be elucidated. In this study, boron application was used at three stages, including pre-flowering, full-flowering, and early fruiting in the ‘Kuerle Xiangli’ (Pyrus sinkiangensis Yu), with a focus on cell expansion and endogenous phytohormone. As a result, treatment with 0.3% boric acid significantly increased endogenous boron concentrations in both leaves and ovaries and enhanced ovary fresh weight as well as both longitudinal and transverse diameters. Histological analysis revealed pronounced cell expansion at 5, 10, and 15 days after pollination (DAP) following boron treatment. Furthermore, gibberellin and trans-zeatin concentrations at 5 and 10 DAP were significantly elevated, while the concentrations of abscisic acid and auxin were markedly reduced. Quantitative real-time PCR (qRT-PCR) analysis demonstrated that boron positively regulates the expression of auxin-related genes, like PbARFH, PbARFD and PbSAUR76-like. In the gibberellin signaling pathway, the expression PbGID1, PbGID1C-like and PbGID2 was activated to drive cell expansion with the boron application. In the abscisic acid signaling pathway, boron treatment induced downregulation of PbSRK2.4, PbABF2, and PbABF2-like in the ovary. Furthermore, boron treatment induced high expression of hormone signaling genes in cytokinin, brassinolide, jasmonic acid and salicylic acid signaling pathways. These findings provide insights into the mechanisms of cell expansion and hormonal changes by which boron modulates early ovary development, offering a basis for improving fruit quality through optimized boron application.