Reakcja polskich odmian uprawych soi (Glycine max (L.) Merr.) na stosowanie brasinosteroidu

In the present study, we evaluated the effects of exogenously applied 24- -epibrassinolide – one of the brassinosteroids – on the seed yield, seed chemical composition (content of soluble proteins, phytoestrogens, carbohydrates, minerals) and resistance to drought of soybean cultivated in Poland (cv. Aldana and Augusta). Quantitative and qualitative analysis of brassinosteroid content was made in seeds of plants treated with 24-epibrassinolide. Experiments were performed in the field and in greenhouse. Brassinosteroid was applied via presowing seed soaking (0,25 mg·dm-3) and spraying of plants (1 mg·dm-3). 24-epibrassinolide affected the increase of the weight of seeds per one plant (27-73%) depending on the cultivar as well as growth conditions (occurrence or lack of drought factor at the stage of seed setting). In the seeds, 24- -epibrassinolide did not change content of proteins or soluble carbohydrates, but increased phytoestrogen genistein content in cultivar Aldana and decreased level of potassium in cultivar Augusta and calcium level in cultivar Aldana. In soybean seeds, the presence of brassinolide and castasterone was found. 24-epibrassinolide applied exogenously to plants was not accumulated in newly formed seeds. In drought-stressed soybean brassinosteroid showed protective effect on net photosynthesis and photosystem II efficiency.Badano oddziaływanie brasinosteroidu – 24-epibrasinolidu – na plonowanie, skład chemiczny nasion (zawartość białek, cukrów, fitoestrogenów i składników mineralnych) oraz odporność na suszę uprawianej w Polsce soi odmian Aldana i Augusta. Przeprowadzono ilościową i jakościową analizę zawartości brasinosteroidów w nasionach roślin traktowanych 24-epibrasinolidem. Eksperymenty wykonano w warunkach poletkowych oraz w szklarni. Brasinosteroid aplikowano poprzez przedsiewne moczenie nasion (0,25 mg·dm-3) i oprysk roślin (1 mg·dm-3). 24-Epibrasinolid wpływał na wzrost masy nasion w przeliczeniu na jedną roślinę (od 27-73%) w zależności od odmiany oraz warunków wegetacji (wystąpienie lub brak czynnika suszy w okresie zawiązywania nasion). Nie oddziaływał na poziom białek i cukrów rozpuszczalnych w nasionach, ale zwiększał zawartość fitoestrogenu genisteiny (odmiany Aldana) oraz zmniejszał poziom potasu (odmiany Augusta) i wapnia (odmiany Aldana). W nasionach soi stwierdzono obecność dwóch ważnych brasinosteroidów: brasinolidu i kastasteronu. 24-Epibrasinolid, którym traktowano rośliny, nie był akumulowany w nasionach. Wykazywał natomiast działanie ochronne na proces fotosyntezy u soi rosnącej w warunkach suszy

Design, synthesis and biological activities of new brassinosteroid analogues with a phenyl group in the side chain

We have prepared and studied a series of new brassinosteroid derivatives with a p-substituted phenyl group in the side chain. To obtain the best comparison between molecular docking and biological activities both types of brassinosteroids were synthesized; 6-ketones, 10 examples, and B-lactones, 8 examples. The phenyl group was introduced into the steroid skeleton by Horner-Wadsworth-Emmons. The docking studies were carried out using AutoDock Vina 1.05. Plant biological activities were established using different brassinosteroid bioassays in comparison with natural brassinosteroids. Differences in the production of the plant hormone ethylene were also observed in etiolated pea seedlings after treatment with new brassinosteroids. The most active compounds were lactone 8f and 6-oxo derivatives 8c and 9c, their biological activities were comparable or even better than naturally occurring brassinolide. Finally the cytotoxicity of the new derivatives was studied using human normal and cancer cell lines

Induced Variations in Brassinosteroid Genes Define Barley Height and Sturdiness, and Expand the Green Revolution Genetic Toolkit

Reduced plant height and culm robustness are quantitative characteristics important for assuring cereal crop yield and quality under adverse weather conditions. A very limited number of short-culm mutant alleles were introduced into commercial crop cultivars during the Green Revolution. We identified phenotypic traits, including sturdy culm, specific for deficiencies in brassinosteroid biosynthesis and signaling in semidwarf mutants of barley (Hordeum vulgare). This set of characteristic traits was explored to perform a phenotypic screen of near-isogenic short-culm mutant lines from the brachytic, breviaristatum, dense spike, erectoides, semibrachytic, semidwarf, and slender dwarf mutant groups. In silico mapping of brassinosteroid-related genes in the barley genome in combination with sequencing of barley mutant lines assigned more than 20 historic mutants to three brassinosteroid-biosynthesis genes (BRASSINOSTEROID-6-OXIDASE, CONSTITUTIVE PHOTOMORPHOGENIC DWARF, and DIMINUTO) and one brassinosteroid-signaling gene (BRASSINOSTEROID-INSENSITIVE1 [HvBRI1]). Analyses of F2 and M2 populations, allelic crosses, and modeling of nonsynonymous amino acid exchanges in protein crystal structures gave a further understanding of the control of barley plant architecture and sturdiness by brassinosteroid-related genes. Alternatives to the widely used but highly temperature-sensitive uzu1.a allele of HvBRI1 represent potential genetic building blocks for breeding strategies with sturdy and climate-tolerant barley cultivars

Induced Variations in Brassinosteroid Genes Define Barley Height and Sturdiness, and Expand the Green Revolution Genetic Toolkit

Reduced plant height and culm robustness are quantitative characteristics important for assuring cereal crop yield and quality under adverse weather conditions. A very limited number of short-culm mutant alleles were introduced into commercial crop cultivars during the Green Revolution. We identified phenotypic traits, including sturdy culm, specific for deficiencies in brassinosteroid biosynthesis and signaling in semidwarf mutants of barley (Hordeum vulgare). This set of characteristic traits was explored to perform a phenotypic screen of near-isogenic short-culm mutant lines from the brachytic, breviaristatum, dense spike, erectoides, semibrachytic, semidwarf, and slender dwarf mutant groups. In silico mapping of brassinosteroid-related genes in the barley genome in combination with sequencing of barley mutant lines assigned more than 20 historic mutants to three brassinosteroid-biosynthesis genes (BRASSINOSTEROID-6-OXIDASE, CONSTITUTIVE PHOTOMORPHOGENIC DWARF, and DIMINUTO) and one brassinosteroid-signaling gene (BRASSINOSTEROID-INSENSITIVE1 [HvBRI1]). Analyses of F2 and M2 populations, allelic crosses, and modeling of nonsynonymous amino acid exchanges in protein crystal structures gave a further understanding of the control of barley plant architecture and sturdiness by brassinosteroid-related genes. Alternatives to the widely used but highly temperature-sensitive uzu1.a allele of HvBRI1 represent potential genetic building blocks for breeding strategies with sturdy and climate-tolerant barley cultivars