Chapter

Physiological effects related to brassinosteroid application in plants

DOI: 10.1007/978-94-007-0189-2_7

ABSTRACT Brassinosteroids are plant hormones whose functions have been discovered in the past years. In order to confirm scientifically
the biological effects caused exclusively by these compounds, different tools can be used, such as BRdeficient or BR-perceptive
mutants, molecular studies, biological assays, application of brassinosteroid biosynthesis inhibitors, endogenous quantification
and exogenous application. This work aims at relating the physiological effects in plants when exposed to different dosages
and analogues of brassinosteroids during different phases of development (germination, flowering, fructification) and when
submitted to biotic and abiotic stress (pathogens, water stress, saline stress, hypoxia, temperature, heavy metals and pesticides)
as well as the particularities related to tropisms, circadian rhythms and interactions with other plant hormones. The use
of brassinosteroids with the objective of increasing crop yield in the field and to improve the quality of the seedlings has
also received attention in recent papers. The main objective of this chapter is to discuss the physiological effects that
occur in cells, tissue or whole plants when submitted to brassinosteroid applications, taking into account the possible mechanism
of action of these compounds and their practical use in agriculture, describing the analogues and the dosages used in field
and laboratory experiments during the last 10 years.

Key wordsbrassinosteroid concentration-brassinosteroid analogue-germination-flowering-plant tissue culture-plant stress

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