Brassinosteroid phytochormones as regulators of plant growth and modulators of pesticide and fertilizer activity

Abstract

SUMMaRY The mode of action of agrochemicals on plants implies the totality of their effect on plant metabolism, growth and development. The effects of different doses of 24-epibrassinolide (24-EBL) as a class of brassinosteroid phytohormones on growth and other physiological processes in maize plants during different development stages are reviewed in order to assess the influence of these agrochemicals on various factors determining the yield of maize as an important agricultural crop. In addition, several examples are given of the effects of these phytohormones on other crops, fruits and vegetables, in terms of their effect on yield, yield quality, and increase in crop resistance to some types of stress. Own results are discussed in the context of other literature data. volume; LMR, RMR, SMR (g g -1 ): relative dry weight of plant parts (leaves, roots, stem); dH (J mol -1 K -1 ): differential enthalpy of different parts (R: radicle; P: plumule; RoS: rest of seed) of 25 maize seedlings exposed to T(reatments) of different molar concentrations of 24-EBL; ΔG 105 (J mol -1 K -1 ) differential Gibbs free energy of total maize plant and their parts (R: roots; L: leaves; S: stem) assesed at 105 0 C; ZP434, ZP704, ZP505: maize hybrids; Fv/Fm, , Fv/F 0 , ФРS 2 , qP, NPQ, RFD 730 (all in relative units), ETR (μmol electrons m -2 s -1 ): different Chl a fluorescence parameters; Pphy, Pi: phosphorus bond to phytic acid and free phosphorus available to many cellular biochemical reactions; GSH: reduced form of gluthathyone; K, Ca, Fe, Mg, Zn, Si: different chemical elements.