Different effects of calcium and penconazole on primary and secondary metabolites of Brassica napus under drought

Probiotics, Proline and Calcium Induced Protective Responses of Triticum aestivum under Drought Stress

In order to increase plants tolerance to drought, the idea of treating them with stress-protecting compounds exogenously is being considered. In this study, we aimed to evaluate and compare the impact of exogenous calcium, proline, and plant probiotics on the response of winter wheat to drought stress. The research was carried out under controlled conditions, simulating a prolonged drought from 6 to 18 days. Seedlings were treated with ProbioHumus 2 µL g^-1 for seed priming, 1 mL 100 mL^-1 for seedling spraying, and proline 1 mM according to the scheme. 70 g m^-2 CaCO₃ was added to the soil. All tested compounds improved the prolonged drought tolerance of winter wheat. ProbioHumus, ProbioHumus + Ca had the greatest effect on maintaining the relative leaf water content (RWC) and in maintaining growth parameters close to those of irrigated plants. They delayed and reduced the stimulation of ethylene emission in drought-stressed leaves. Seedlings treated with ProbioHumus and ProbioHumus + Ca had a significantly lower degree of membrane damage induced by ROS. Molecular studies of drought-responsive genes revealed substantially lower expression of Ca and Probiotics + Ca treated plants vs. drought control. The results of this study showed that the use of probiotics in combination with Ca can activate defense reactions that can compensate for the adverse effects of drought stress.

Genome-wide identification and expression analysis of CaM/CML genes in Brassica napus under abiotic stress

Calmodulin (CaM) and calmodulin-like (CML) proteins are primary calcium (Ca²⁺) sensors and are involved in the regulation of plant development and stress responses by converting calcium signals into transcriptional responses, protein phosphorylation, or metabolic changes. However, the characterization and expression profiling of CaM/CML genes in Brassica napus remain limited. The present study reports that 25 BnaCaM and 168 BnaCML genes were identified in B. napus. The phylogenetics, gene structures, gene motifs, gene chromosomal locations, syntenic and Ka/Ks analysis, promoter cis-acting elements, and expression characteristics in various organs and under abiotic stress were evaluated. The phylogenetic results revealed a total of 11 subgroups, including one unique clade of CaMs distinct from CMLs. Most of group I (CaM), II, III, and X members are intron rich, while members from the other seven groups are intron-less. The majority of CaM/CML proteins have four EF-hands. Syntenic analysis showed that 91.3 % orthologous CaM/CML gene pairs between B. rapa and B. oleracea were retained as homologous gene pairs in B. napus. Ka/Ks analysis indicated that the majority of BnaCaM/CML experienced purifying selection. Expression analysis showed that BnaCaMs genes are highly and ubiquitously expressed in all of the organs and tissues examined, while distinct BnaCMLs are expressed specifically in particular organs and tissues. In total, 129 BnaCaM/CML were induced by abiotic stress and phytohormones. BnaCMLs from group IV, VI, VIII, and X were strongly induced by freezing treatment, but were not or just slightly induced by chilling treatment. The present study is the first to analyze the CaM/CML gene family in B. napus, which is useful for understanding the functions of the BnaCaM/CML in modulating plant responses to abiotic stress, especially freezing stress.