Q&A: what are brassinosteroids and how do they act in plants?Brassinosteroids BRs are specific phytosteroids necessary for ordinary plant growth and development. BRs share similar chemical structures with animal steroidal hormones, but show a distinctive signal perception mechanism. Xtructure importance of BRs is illustrated by the structure and function of brassinosteroids phenotypes of mutants with lesions in key biosynthetic or signalling proteins. Extensive studies in the last four decades have resulted in a comprehensive picture of BRs, from their nearly completed biosynthesis and physiological functions to their mechanisms of action. Brassinosteroids BRs are essential plant hormones regulating various developmental processes.
Brassinosteroids BRs are a class of polyhydroxysteroids that have been recognized as a sixth class of plant hormones. These were first explored nearly 40 years ago, when Mitchell et al. Since their discovery, over 70 BR compounds have been isolated from plants.
The BR is biosynthesised from campesterol. The biosynthetic pathway was elucidated by Japanese researchers and later shown to be correct through the analysis of BR biosynthesis mutants in Arabidopsis thaliana , tomatoes, and peas. One well-supported hypothesis is that all tissues produce BRs, since BR biosynthetic and signal transduction genes are expressed in a wide range of plant organs, and short distance activity of the hormones also supports this. Extract from the plant Lychnis viscaria contains a relatively high amount of Brassinosteroids.
Lychnis viscaria increases the disease resistance of surrounding plants. It was shown that the percentage of chromosomal aberrations induced by maleic hydrazide 0. BRs have been reported to counteract both abiotic and biotic stress in plants. Application of epiBL have any protective role on shoot, root length, soluble protein, proline content and peroxidases along with proline content PPO and IAA in seedlings of B. BRs have also been reported to have a variety of effects when applied to rice seeds Oryza sativa L.
Seeds treated with BRs were shown to reduce the growth inhibitory effect of salt stress. BIN2 and its close homologues inhibit several transcription factors. BR might reveal to have a prominent interest in the role of horticultural crops. Based on extensive research BR has the ability to improve the quantity and quality of horticultural crops and protect plants against many stresses that can be present in the local environment.
BR could also help bridge the gap of the consumers' health concerns and the producers need for growth. A major benefit of using BR is that it does not interfere with the environment because they act in natural doses in a natural way. In Germany, extract from the plant is allowed for use as a "plant strengthening substance. BRs can be detected by gas chromatography mass spectrometry and bioassays.
From Wikipedia, the free encyclopedia. Plant Physiology and Biochemistry. Essential Regulators of Plant Growth and Development". Journal of Agricultural and Food Chemistry. In Hayat S, Ahmad A.