High oil corn hybrids improvement

Twenty three high oil corn lines, which extracted S3-S6 lines, that to be used as female parent were selected from 119 lines of 3 populations: AHO, IHO and DAHO. They were factorial crossed with 3 inbred lines of the Corn Breeding Project of Kasetsart University (Ki) namely Ki 35, Ki 41 and Ki 44, that made in total 69 hybrids. Yield trial hybrids was done with 9 cooperative hybrids of high oil corn and 3 check varieties. The test was done in early rainy season in 1997 at 2 locations, Suwan Farm (National Corn and Sorghum Research Center) and Lopburi Experiment Station. Kernel from Suwan Farm was analyzed at the Chainat Field Crops Research Center to find out chemical composition in kernel. The study showed that AHO-S1-no.-S5-86-4-1 (yield 668 kg/rai, oil 6.20 percent) was good specific combining ability with Ki 35 and Ki 44, which produced grain yield of 1480 and 1,164 kg/rai (oil 5.40 percent and 5.56 percent) at National Corn and Sorghum Research Center and Lopburi Experiment Station, respectively. Heritability of yield that effect by male and female parents at Suwan Farm, was 9 percent and 33 percent which the total of 84 percent; and at Lopburi Experiment Station was 2 percent and 30 percent which the total of 56 percent. The (AHO x Ki 37)-no.-S5-76-9-1 (yield 358 kg/rai, oil 6.36 percent) was good specific combining ability with Ki 44 which produced oil content 7.78 percent (yield 813 kg/rai) and produced high oil content of 7.22 percent, 6.31 percent and 6.29 percent when combined with Ki 35, Ki 32 and Ki 41, respectively. Heritability of oil content that effected by male and female parents were 1 percent and 23 percent with the total of 55 percent. The study of correlations of yield with some agronomic characters revealed that there were positive correlations with plants per area, ears per plant, shelling percentage, plant and ear height. However, there was negative correlation with the oil percentage. Moreover, it was found that there was negative correlation between protein, oil and starch percentage. Therefore, there was protein both in embryo and endosperm.