Evaluation and preliminary yield comparison of new grain corn (Zea mays L.) hybrids in saline and non-saline conditions.

In order to selection and screening of new grain corn (Zea mays L.) hybrids, 52 new combinations from mating of S6 maternal parents (consisted of 24 combinations among mathernal parents with late mature testers named K3615/1 and A679 and 28 combinations from crosses among S6 lines with early mature testers named K1263/1 and K1264/5-1) with 3 commercial hybrids named KSC400, KSC700 and KSC704 laid out in 2 RCBD with 3 replications in Torough Agricultural Research Station, Mashad (non-saline) and Abbas Abad-Tangalshour mashhad (saline condition with EC 6.1 and 15.6 for water and saturated paste, respectively), Iran on 2010. The seeds of hybrids were planted on 2 rows of 5 meters with 76000 plant/ha density and morphological traits and grain yield and it's components were studied. The results of ANOVA showed that the combinations of S6 lines with K3615/2 and A679 testers had significant differences for all of measured traits except for grain yield and kernels/row. Means comparison showed that hybrid no. 10 (L13 X A679) with 12.84 ton/ha and hybrid no. 14 (L19 X A679) with 6.61 ton/ha had the highest and lowest grain yield, respectively. Also, The results of ANOVA showed that the combinations of S6 lines with k1263/1 and K1264/5-1 testers had very significant differences (P¡Ü0.01) for all of measured traits except for grain yield, plant height and and Anthesis Silking Interval (ASI). Means comparison with Duncan's Multiple Range Test method showed that hybrid no. 9 (L17 X k1263/1) with 15.400 ton/ha and hybrid no. 17 (L6 X k1264/5-1) with 9.200 ton/ha had the highest and lowest grain yield, respectively. Furthermore, the commercial hybrid KSC704 with 15.22 ton/ha had no significant differences in compared to the best hybrid. The Abbas Abad station experiment damaged cold due to occurance of cold stress in late summer 2010. Selection of proper planting time especially mid-June for late mature corn hybrids in mashhad prefered to early mature hybrids. Of course, mid and early mature corn hybrids are better than late mature in relay cropping at short season period.