ENZYME EFFECTORS INFLUENCING SAI AND SPS ACTIVITY AND IMPROVING SUCROSE CONTENT IN SUGARCANE STALK

摘要

Present investigation was aimed to modulate SPS and SAI activities and improving sucrose content in cane stalk using enzyme effectors (MgCl_2, MnCl_2, GA_3 and ethrel). Application of enzyme effectors; magnesium (Mg) as magnesium chloride (10mM), manganese (Mn) as manganese chloride (5mM), GA_3 (50ppm) and ethrel (400ppm) along with a water treated control at early stage of crop growth (formative phase) enhanced leaf SPS activity and decreased SAI activity in leaf tissues and growth attributes, fresh weight of different plant parts. In vitro studies with enzyme effectors revealed inhibitory effect of Mn and Mg on SAI activity and stimulatory on SPS activity. Further application of Mn and Mg enhanced sucrose content, CCS % juice and juice purity at the early stage of cane ripening. Increase in sucrose content ranged from 17.8 to 24.8%, 2.5 to 34.5%, 7.7 to 35.1%, 0.33 to 15.8% and 2.2 to 2.5% over control at 240, 270, 300, 330 and 360 days after planting (DAP), respectively; the highest increase was observed with Mg treatment. In contrast to cane maturant/ ripener, their application improved plant biomass in addition to enhancing total sugar content in cane stalk. Findings suggested enhanced plant biomass and sugar yield by applying enzyme effectors especially Mg and Mn at early stage of crop growth and ripening, respectively.