Changes in physio-biochemical attributes and gene expression in sugarcane in response to ethephon under drought conditions Jain Radha*, Giri Priyanka, Gupta Ankita ICAR-Indian Institute of Sugarcane Research, Lucknow - 226 002, Uttar Pradesh, India *Corresponding author Email: radha_dinesh@yahoo.co.in
Online published on 28 April, 2023. Abstract The effect of ethephon under drought conditions in improving the tolerance in sugarcane was studied using the variety CoLk 94184 at early growth stage. Single bud setts were first soaked overnight in graded levels of ethephon viz., 100 ppm, 200 ppm and 400 ppm solutions, planted under tray culture conditions and maintained under net house conditions. Drought condition was created by withholding water supply in the treatments, D1 (drought), D2 (drought + 100 ppm ethephon), D3 (drought + 200 ppm ethephon) and D4 (drought + 400 ppm ethephon). An untreated control (C) was maintained with adequate water supply. After 25 days of planting, bud sprouting and growth parameters were recorded. Results obtained indicated higher bud sprouting, plant vigor, root numbers, length and weight in drought + ethephon treatments (D2 to D4) as compared to drought alone (D1). Biochemical studies revealed increasing levels of reducing, total and non-reducing sugars, proline content in bud tissues in D1 (drought) treatment. Further, these attributes were relatively higher in drought + ethephon treatments. Sprouted bud tissues used for gene expression analysis indicated increased superoxide dismutase (SOD) gene expression in almost all the treatments (D1 to D4) as compared to the control plant, with the highest recorded in D3 treatment (drought + 200 ppm ethephon). Similarly, the expression of ethylene responsive (ETR) gene was higher in drought and drought + ethephon treatments and lowest in the control (C). A house keeping actin gene was used as internal control in expression study. Findings suggested beneficial effect of setts priming with ethephon on drought tolerance. Ethephon at 100 ppm and 200 ppm was found to be effective doses for pre-planting treatment. Top Keywords Drought, Sugarcane, Ethephon, Biochemical studies, Gene expression, SOD gene, ETR gene, Actin gene). Top |