Abstract:In order to research the correlation between the endogenous auxin and defoliation of sugarcane, the contents of abscisic acid (ABA), ABA-glucosyl ester (ABA-GE), 1-aminocyclopropanecarboxylic acid (ACC), jasmonic acid (JA) and related derivatives jasmonic acid-valine (JA-val) in leaf sheath bases at different positions were determined at different mature stages. The results showed that the change trends of ABA and JA-val contents in LZ02-169 with maturity were consistent with that of shedding rate, while the ACC content in +8 leaf sheath base of LZ02-169 and defoliation rate was opposite. The contents of ABA, ABA-GE and JA-val in +8 leaf sheath base of LZ02-169 at late mature stage were significantly higher than those of 'GT47'. Therefore, the increase of ABA content might accelerate the abscission of sugarcane leaves at late mature stage, and ethylene derived from ACC and JA-Val also promoted the abscission of sugarcane leaves.
