| Head smut of corn is a kind of worldwide disease, is also one of the main diseases of spring corn-producing areas in China. This disease spread through the soil or seed infection fungal diseases, pathogens wire axis black powder bacteria [Sporisorium reilianum(Kuhm) Langdon et Full] in maize seedlings underground part of the intrusion, the system infection, the adult stage performance of the typical symptoms, tassel and Ear produce spores of black powder, can cause the corn a lot of cuts, so the choice of quality disease-resistant hybrids is one of the control wire smut is the most effective way. Based on the resistance identification of inbred Iines of common corn; The inheritance of resistance of corn was studied with in incomplete diallel cross, The results as follows:1.Adopt the new resistance evaluation standards, and through the 11 maize inbred lines and equipping of artificial inoculation identification of 30 hybrid combinations.Studies have found that there are 6 of disease-resistant inbred lines, accounting for 63.6% of the total material identification of inbred lines, the performance of disease-resistant Mo17, F349 two material, resistant performance of J1495 J1255, S122, Dan340;An inbred lines with 5 copies.Hybrid combinations resistant type 22, accounting for 73.33% of the total cross combination, at the same time see the disease resistance of hybrid F1 generation depends on his father’s female parent their disease resistance, and its incidence is close to the average incidence of parents, so to have good resistance of equipping, choose good resistance and other excellent parent shape.2. The inheritance of resistance to S.reilianum was studied from 30 hybrid combinations and 3 of corn six generations. The results showed that the disease incidence of F1 was between the resistant and susceptible parents. and approached to th eaverage of Parents,Resistance of F2 is higher than that of F1, resistance of BC was up to resistance level of parents.Additive gene effects plays a main role in the inheritance of resistance to S.reilianum.at the same time dominance effects and epistatic effects exist, and gene effect was variable in different genetic background.3.Set inoculated corn and uninoculated corn in two conditions, under the condition of two kinds of hybrid F1 for combining ability analysis, the results showed that the value of general combining ability and special combining ability were different under the two conditions, ear weight and ear row number suffered impact is small, inbred lines J1255 has higher general combining ability in yielding character, J1495, chang 7-2 and F349 general combining ability of inbred lines GCA is higher,Yielding of the SCA in no inoculated S.reilianum condition of the J1255×Chang7-2 up to 23.77,Zheng58×Chang7-2 and Zheng58×F349 were higher,respectively,16.59 and 14,PH4CV×Huang zao 4 minimun. Yielding of the SCA in inoculated S.reilianum condition of the J1255×F349 up to 11.82,the value of J1255×Chang7-2 was 11.06, Zheng58×Huang zao 4 minimun.Based on the above results that J1255×Chang7-2, Zheng58×F349 better.4. In aspect of heritability, the results of incomplete diallel cross experiment showed that the value of heritability was different under inoculation and uninoculation conditions, but the trend was the same.Under two conditions the narrow heritability and the wide heritability of ear row number were the highest.In inoculation condition the value of narrow and wide heritability of ear row number was 76.45% and 82.97%,the other that was 69.75% and 80.19%,so it was feasible on selection in the earlier generations.The narrow heritabilities of Plant height,ear height, ear width were higher,but the narrow heritability of ear kernel weight was lower.Under the two condition the value of narrow heritability of ear kernel weight were 31.05% and 26.87%,so we shoud select it in late generation.5. Results of tested genetic model: The results of three generation mean analysis experiment showed the heredity of ear grain weight conformed to additive-dominanceepistatic genetic model. Additive effects and dominance effects were more important.The100-grain weight,plant height,ear height,ear length, ear width and kernel per row conformed to additive-dominance-epistatic genetic model.The 100--grain weight was controlled by additive effects.Plant height,ear height,ear length were controlled by dominance effects.Ear width was controlled by dominance effects and epistatic effects.Kernel per row was controlled by dominance effects and dominance effects,but the dominance effects was predominant. |
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