WATER STRESS AFFECTS THE GERMINATION, EMERGENCE AND GROWTH OF DIFFERENT SORGHUM CULTIVARS

Abstract

Two experiments were conducted to study the effects of water deficit stress on the
germination, emergence and seedling growth of sorghum [Sorghum bicolor (L.) Moench] using
Completely Randomised Block Design in four replications. Five sorghum cultivars (Jigurti, Gambella
1107, Meko, 76 T1 #23 and P9403) were evaluated under three water deficit stress treatments (0, -0.20
and -0.85 MPa) using PEG as an osmoticum (Experiment I) and under four varying growing media
water contents (100, 60, 40 and 20% of field capacity) using sand (Experiment II). In both experiments,
water deficit stress significantly reduced the rate and percentage of germination and emergence and
early seedlings growth. Coleoptile, mesocotyl, radicle, and seedling shoot and root lengths, as well as
root area were adversely affected by water deficit stress. Cultivars differed in the rate and percentage of
germination, and emergence and seedling growth. Gambella 1107, Meko and P9403 had significantly
(P<0.01) higher rates and percentages of germination and emergence. The rate of germination and
emergence, the growth of the coleoptile, mesocotyl, and radicle and the shoot and root length and root
area were found important traits to identify cultivars tolerant to water deficit stress at germination