Evaluation and selfeing of Maize hybrids and populations to select drought tolerance hybrids and producing S3 lines.

The design were conducted at Safiabad Agriculture Research Center (SARC), location in Dezful with arid and semi arid climate, for five years during 2005-2009. It has two parts, the first was comparison of three trials of cimmyt maize hybrids and the second, producing S3 maize lines from cimmyt populations. The result showed that, in the Tropical Threeway Crosses White Late Trial (TTWCWL04) with 20 hybrids, the hybrid one (AF04A432-25x26), eleven(AF04A432-21x22) and thirteen (F04A432-3x4) with 10.41, 9.99 and 9.02 t/ha respectively were better than local checks SC704 and SC700 with 5.73 and 5.49 t/ha respectively. In the Cimmyt Hybrid Trial-Tropical White QPM (CHTTWQ04)with 25 hybrids, the hybrid eight (F03B5300-3x4), five(AF03B5261-15x16) and fifteen (AF03B5261-37x38) with 8.44, 8.21 and 8.01 t/ha respectively were better than local checks SC704 and SC700 with 5.68 and 4.71 t/ha respectively and in the Cimmyt Hybrid Highland Late White (CHTHLW04) with 12 hybrids, all of the them had yield less than local check SC704 with 6.718 t/ha. Moreover, in the part tow of the design, 164 Cimmyt populations were evaluated under drought stress condition and 63 S3 lines produced. The S3 lines were crossed with MO17 line as tester and 43 top crosses produced. The top crosses evaluated under tow conditions, natural irrigation(70 mm evaporation of pan) and drought stress condition(100 to 110 mm evaporation of pan). Based on the results some of the top crosses has appropriate yield and plant performance. But some of them has not good tassel or ear flowers stretcher. Their grain texture was dent, flint or dent-flint and the grain colure was yellow, yellow-orange or yellow-white. Generally top crosses has good performance in natural irrigation but some of them were good under drought condition.