ارزيابي تحمل به خشكي اكوتيپ هاي اسپرس در شرايط ديم و آبي

Evaluating Drought Tolerance of Sainfoin (Onobrychis sativa) Ecotypes under Rain-fed and Irrigated Conditions

To evaluate drought tolerance of 36 sainfoin ecotypes, two separate experiments were conducted under both rain-fed and irrigated conditions in a simple lattice design at Agricultural and Natural Resources Research Center of East Azarbaijan, Iran, during growing season of 2007. Analysis of variance of data collected showed that there were genetical diversity among the ecotypes under both drought stress and non-stress (irrigated) conditions. Mean comparisons revealed that ecotype No. 12 produced, under drought conditions, highest (42.52 T/ha) and No. 26 the lowest (10.5 T/ha) fresh weight yield. It was also found that ecotypes 3 and 12 produced highest dry forage weight (14.45 and 14.62 T/ha) and ecotypes 14 and 26 the lowest (4.79 and 4.78 T/ha) dry forage weight. Highest fresh forage yield under irrigation was 70 T/ha for ecotype 28 and lowest fresh forage yield (31.5 T/ha) for ecotype 11 respectively. Mean comparisons also indicated that ecotype 19 produced highest dry forage weight (23.9 T/ha) and ecotype 14 the lowest dry forage weight under irrigation respectively. From the drought tolerance indices under study, STI and GMP were recognized to be the best indices to use for selection of drought tolerant sainfoin ecotypes. According to these indices ecotype 31 (Herriz local) can be recommend to be the most drought tolerant one.