Monday, November 5, 2007
65-7

Evaluation of Four Barley Cultivars under Terminal Drought Stress.

Nezar Samarah and Ahmad Alqudah. PO Box 3030, JORDAN,Univ.-Sci. & Tech., Jordan University of Science & Technology, Department of Plant Production, Irbid, 22110, JORDAN

Barley (Hordeum vulgare L.) is the first important winter cereal crop grown in Mediterranean regions, where terminal drought stress prevalent during grain filling period. The objectives of this study were to evaluate four barley cultivars for growth performance and yield under late-terminal drought stress both under glasshouse and field condition. Four barley cultivars (Rum, ACSAD176, Athrouh, and Al-Yarmouk) were exposed to three drought stress treatments when reached to grain filling: (1) Well-watered at 75% field capacity (FC), (2) Mild-drought stress at 50% FC, (3) Severe-drought stress at 25% FC in the glasshouse experiment and (1) Rainfed (control) non irrigation, (2) Moderately-irrigated (once every two weeks), (3) Well-irrigated (once a week) in the field experiment. Morphological, physiological and yield and yield components data were recorded. Drought stress treatments significantly decreased plant height and spike length and shortened grain filling duration compared with the well-watered treatments in both experiments. Photosynthetic rate and water potential were decreased as drought stress severity increased. Biological yield and yield components were decreased under drought stress treatments by decreasing 100-grain weight, number of tiller, spike and grain per plant. These data suggest that the old cultivars had either higher or similar yield to the new released cultivars in the glasshouse experiment, while Rum had the highest grain yield in the field experiment.