Analysis Of Dehydration Characteristics Of Hybrids Based On The Combination Of Maize Inbred Line KA105

The whole process mechanized production of maize is the development direction of maize production in the future.Breeding early maturing,dense,suitable for machine harvest and fast dehydration maize varieties is an important measure to improve yield and reduce production cost.In order to clarify the dehydration characteristics and genetic effects of different maize hybrids and their parents,KA105 from Shaan A Group was selected as the female parent,and 19 inbred lines from Shaan B Group were selected as the male parent.Nineteen hybrids were selected and planted with 67,500 plants·ha^-1 and 82,500 plants·ha^-1two planting densities.By analyzing the yield and dehydration characteristics of the hybrid and its parents at two densities,the hybrid with high yield and suitable mechanical harvest and favorable alleles related to grain moisture content were screened.The main results are as follows:1.Cluster evaluate results showed that KB025,KB204,KB089,KB109,KB107,KB019,KB024 and KB128 were fast dehydration inbred lines,and SD662,SD658,SD650,SD669,D660,SD638,SD659 and SD673 were fast dehydration hybrids.2.When the density increased from 67500 plants·ha^-1 to 82500 plants·ha^-1,the grain water content decreased,but there was no significant difference among different inbred lines and hybrids.The high density had a great effect on the material with medium dehydration rate,and the dehydration rate increased at the later stage,and the water content before harvest was basically consistent with that of the material with high dehydration rate.The yield of different inbred lines and hybrids was significantly different between the two densities,and the yield increased with the increase of density.3.Inbred lines and hybrids in grain moisture content at harvest reached extremely significant positive correlation,and under the condition of female parent were KA105,hybrid grain moisture content of materials of high moisture content of the inbred lines is high also,hybrid materials of the grain moisture content is low and a low moisture content of the inbred lines,for low moisture content of the hybrid breeding harvest time,need to pay attention to the choice of their grain moisture content.4.By integrating the existing association analysis results,it was confirmed that the recessive homozygous gene of Aff X-88982545 and the non-dominant homozygous gene of AFFX-291405157 and AFFX-291444075 were favorable alleles,which could be used to improve the seed water content by developing molecular markers.To sum up,this experiment screened KB019,KB024,and KB107 as high-yield and density-tolerant and suitable for mechanized harvest inbred lines,and SD650,SD662 as high-yield and density-tolerant and suitable for mechanized harvest hybrids,which could be used in production practice to assist mechanized production.Meanwhile,the paternal effect of seed moisture content of the hybrids was clarified,and combined with previous results in the laboratory,The genetic loci related to grain moisture content were screened out,and the results provided reference for selecting hybrid combinations with high yield,density tolerance and good yield in breeding practice.