10个糯玉米自交系穗部性状配合力及其遗传特性分析

Combining ability for ear traits of ten waxy maize inbred lines

【目的】分析10个糯玉米自交系的穗部性状配合力及其遗传特性,为高效利用亲本材料选育穗部性状优良的糯玉米品种提供理论依据。【方法】按不完全双列杂交设计(NCⅡ),以10个糯玉米自交系为被测系(A1~A10)与5个测验种(B1~B5)组配50个杂交组合,通过春播和秋播2次试验,调查F1代穗部性状(穗长、穗粗、秃尖长、穗行数和行粒数)的一般配合力(GCA)、特殊配合力(SCA)、广义遗产力和狭义遗传力。【结果】50个杂交组合穗部性状春播平均值均大于秋播平均值。秋播穗部性状(除穗行数外)的变异系数大于春播,春播和秋播中秃尖长的变异系数均最大,约50.0%,而其余性状的变异系数均在10.0%左右。综合春播和秋播2次试验,A3(T2)、A4(JS0381)和A6(S181)穗长、穗粗、行粒数和穗行数的GCA表现为较高正向效应,秃尖长表现为负向效应,综合表现较好,以其组配的杂交组合A6×B3(S181×JN2-8)、A6×B5(S181×RJ)、A6×B2(S181×W150)、A4×B5(JS0381×RJ)和A3×B5(T2×RJ)的多数穗部性状SCA也较高,且SCA效应值排名前10位,是强优势组合。春播和秋播中穗长和穗粗GCA方差均较高(>80.0%),且远高于SCA方差,秃尖长和行粒数GCA和SCA方差相近;穗长、秃尖长和穗行数的广义遗传力和狭义遗传力均较大(>54.0%),穗粗和行粒数的广义遗传力和狭义遗传力均较小(<45.0%)。【结论】S181、T2和JS0381综合表现较好,具有较大的育种潜力,易组配出穗部性状优良的杂交组合,可在育种实践中重点利用。穗长、秃尖长和穗行数可进行早代选择,而穗粗和行粒数宜晚代选择。

【Objective】Estimation of combining ability and genetic characteristics for ear traits of ten waxy maize could help to use parent materials efficiently and provide theoretical guidance for selecting waxy maize varieties with good ear traits.【Method】Ten elite tested waxy lines(A1-A10)were tested lines,and they were hybridized following incomplete diallel cross experiment design(NCⅡ)with five inbred lines as testers(B1-B5).The fifty hybrid combinations were sown in spring and autumn to evaluate their general combining ability(GCA),special combining ability(SCA),broad-sense heritability(BSH)and narrow-sense heritability(NSH)of ear length(EL),ear width(EW),tip-barren length(TBL),kernel row number(KRN)and kernel number per row(KNR)of F1 generation ear traits.【Result】The means of ear traits in spring sowing(SS)for 50 combinations were higher than in autumn sowing(AS).The coefficient of variation of ear traits(except KRN)were higher in AS than in SS,and the highest value(nearly 50.0%)was in TBL but the others were about 10.0%.According to the results in spring sowing(SS)and autumn sowing(AS),the GCA of EL,EW,KRN and KNR for inbred lines A3(T2),A4(JS0381)and A6(S181)had high positive effects,and ETL had negative effects,which suggested that they had better performance than others.The SCA for most of ear parameters in cross combinations using these elite inbred lines were higher,such as A6×B3(S181×JN2-8),A6×B5(S181×RJ),A6×B2(S181×W150),A4×B5(JS0381×RJ)and A3×B5(T2×RJ),which ranked among the top 10 in all combinations and were considered as strong dominance combinations.The GCA variance of EL and EW(>80.0%)were high in spring sowing(SS)and autumn sowing,and were greatly higher than SCA variance,and the GCA variance of TBL and KNR were similar with the values of SCA variance.Based on genetic characteristics,EL,TBL and KRN showed high BSH and NSH(>54.0%),and EW and KNR showed lower BSH and NSH(<45.0%).【Conclusion】The inbred lines S181,T2 and JS0381 performance is fine,and they have strong breeding potential,which can easily produce hybridized combination with good ear traits,and can be utilize in breeding practices.EL,TBL and KRN should be selected in early generation and EW and KNR should be selected in late generation.