Screening Of Suitable Mechanized Traits And Combining Ability Analysis Of 198 Inbred Maize Inbred Lines

With the rapid development of agricultural technology and agricultural mechanization,huge changes have taken place in production methods.The selection and breeding of maize varieties suitable for mechanization has become the key point of the whole mechanization of maize production,and it is also an important direction for the transformation of current agricultural production methods.198 maize inbred lines were introduced to screen maize inbred lines for mechanization.Complete the screening,evaluation and combining ability analysis of suitable mechanized inbred lines,laying the foundation for the direction of suitable mechanized breeding in Jilin Province.The main experimental results of this study are as follows:(1)According to the water content,seed emergence rate,empty stalk rate,bract length and seedling emergence rate during the maturity period,more corn inbred lines were eliminated.Approximately 64.6% of inbred lines were eliminated according to the water content of grains in the mature stage,which is the most important screening index for restricting suitable mechanical harvest.(2)40 out of 198 inbred lines were screened to be suitable for mechanization traits,with a selection rate of 20.2%.(3)The grain water content at mature stage was positively correlated with the number of ear rows,number of bract leaves,air drying water and the correlation coefficient of hectare yield.The correlation coefficient with the number of bract leaves and the correlation coefficient of hectare yield was significant or extremely significant,and the correlation coefficient was 0.4 and0.33,respectively.It was negatively correlated with 100-grain weight,panicle stalk length and seed yield,and the correlation coefficient with panicle stalk length reached a significant level(the correlation coefficient was-0.39).(4)Variance analysis of main agronomic traits showed that there were significant or extremely significant differences in other traits except head smut and empty stalk rate among all test cross combinations.The variances of empty stalk rate,lodging rate,large spot,gray spot and row number of panicles among replicates did not reach significant or extremely significant level.The general combining ability of all traits of inbred lines in groups P1 and P2 reached significant or extremely significant level except empty stalk rate,lodging rate and head smut.Except for head smut,the special combining ability of other characters reached significant or extremely significant level.(5)Perform combining ability analysis on 160 hybrid combinations.According to the general combining ability of important traits such as yield,empty stalk rate,lodging rate,seed yield,harvested moisture content,6 inbred lines performed better,namely L6,L13,L23,L24,L26,L28.(6)The special combining ability effect value of 160 crosses was greater than 100 in 6 of them.The special combining ability effect value of 40 inbred lines and test species PH6 WC and PH4 CV was higher,among which the special combining ability effect value of L33×PH4CV was 216.63.It can be seen from general combining ability and special combining ability that the inbred lines of L6 and L13 are superior.(7)The generalized heritability of yield and other agronomic traits is 3.19%-96.96%,and the narrow sense heritability is 1.58%-81.1%.The heritability of ear height is the highest,and the heritability of head smut is the lowest.