Effect of drought on physiology and yield contributing characters of sunflower

Abstract

The present study was conducted during 1995 to April 1996 at Bangladesh Agricultural University, Mymensingh to investigate the effect of drought stress at various levels with a view to studying the physiological characters of sunflower associated with yield under drought condition. Two varieties ( Kironi and Hysan-55) and five drought cycles were i) Daily watering, ii) 1 day without water, iii) 2 days without water, iv) 3 days without water, and v) 4 days without water imposed in the study. As a whole, drought treatment reduced the yield and yield contributing characters of sunflower. In most cases, the rate of reduction was higher in plants that received 4 days drought cycle followed by 3 days. The minimum reduction was observed in plants that received 1 and 2 days drought cycle. The growth parameters (CGR, RGR, NAR, and LAI) were reduced under drought treatments. Similar trend was followed in case of CSI values and RWC of the leaves. The rate of reduction for most of characters was higher in Hysan-55 than that of Kironi. Thus, the variety Kironi was found better than Hysan-55 in respect of physiological adaptation associated with yield under drought condition. Keywords: Drought; physiology; sunflower DOI: 10.3329/bjar.v35i1.5872Bangladesh J. Agril. Res. 35(1) : 113-124, March 2010