23份超甜玉米自交系育种潜力分析

Analysis on Breeding Potential of 23 Super-sweet Corn Inbred Lines

【目的】分析23份超甜玉米自交系主要农艺性状的配合力效应并评价其综合指数和育种潜力,为超甜玉米优良自交系和新品种选育提供参考依据。【方法】以20个超甜玉米被测系(A1~A20)和3个超甜玉米测验系(B1~B3)为材料,采用NCⅡ设计得到60个组合,测定各组合出苗至吐丝天数、株高、穗位高、茎粗、穗长、穗粗、穗行数和小区产量等主要农艺性状的配合力,分析各农艺性状的一般配合力(GCA)和特殊配合力(SCA)效应,并进行综合指数评价。【结果】在3个超甜玉米测验系中,B1的综合指数最低,B3最高;在20个被测系中,A12、A3、A9、A13、A19、A18、A1、A20、A16和A10的GCA和综合指数较高,A11的综合指数不高但茎粗的GCA效应值最大,穗位高的GCA效应值较小;组合B3×A3、B3×A20、B2×A8、B3×A5和B3×A4的综合性状表现较好,组合B3×A8、B3×A7、B3×A6、B2×A3、B3×A9、B3×A16、B3×A17和B1×A20几乎所有性状的SCA均为负值,可利用价值不高;出苗至吐丝天数、穗位高、穗粗、穗行数和小区产量的广义遗传力和狭义遗传力均超过50.00%,而株高、茎粗和穗长的狭义遗传力均低于35.00%。【结论】超甜玉米自交系B3是优良的测验系,被测系A12、A3、A9、A13、A19、A18、A1、A20、A16和A10是较优良的自交系;A11在改良植株性状、增加抗倒伏方面具有很高的应用价值;杂交组合B3×A3、B3×A20、B2×A8、B3×A5和B3×A4的综合性状表现较好,可进一步参加多点试验鉴定。

【Objective】Studying the combining ability of the main agronomic traits,evaluating the comprehensive index and breeding potential of 23 super-sweet corn inbred lines could provide basis for breeding excellent inbred lines and new varieties.【Method】20 tested lines(A1-A20)and 3 tester lines(B1-B3)as tested material were used to conduct 60 combinations with NC-Ⅱdesign in order to study the combining ability effect of main agronomic traits including days to silk,plant height,ear height,stem diameter,ear length,ear diameter,number of rows per ear and plot yield,analyze GCA and SCA effect of main agronomic traits and evaluate the comprehensive index.【Result】The comprehensive index of B1 was the lowest and B3 was the highest among three tester systems of super-sweet corn;GCA and comprehensive index of A12,A3,A9,A13,A19,A18,A1,A20,A16 and A10 were higher among 20 tested lines.The comprehensive index of A11 was lower but GCA on stem thickness was the highest and ear height was lower.The comprehensive traits of combinations B3×A3,B3×A20,B2×A8,B3×A5 and B3×A4 were better,while most SCA of combinations B3×A8,B3×A7,B3×A6,B2×A3,B3×A9,B3×A16,B3×A17,B1×A20 was negative whose utilization value was very low.Both broad-sense and narrow-sense heritability of the days to silk,ear height,ear thickness,ear row number and plot yield were more than 50%,while the narrow-sense heritability of plant height,stem thickness and ear length were lower than 35%.【Conclusion】Super-sweet corn inbred lines B3 was a very good tester line and the tested lines A12,A3,A9,A13,A19,A18,A1,A20,A16 and A10 were excellent inbred lines and A11 had good application value in meliorating plant traits and increasing lodging resistance.The comprehensive traits of B3×A3,B3×A20,B2×A8,B3×A5 and B3×A4 were better which could be identified further by participating in multi-point test.