10个糯玉米自交系育种潜力分析

Evaluation on breeding potential of 10 waxy maize inbred lines

【目的】研究不同糯玉米自交系的配合力及遗传参数,为提高糯玉米育种效率提供理论依据。【方法】以10个糯玉米自交系为被测系,5个糯玉米自交系为测验种,采用NCII遗传交配设计,组配50个杂交组合,对其品质、南方锈病发病等级及产量相关性状(鲜穗重、每穗粒重、播种至散粉天数、播种至吐丝天数、株高、穗位高和穗位系数)进行配合力分析,并估算遗传参数。【结果】10个被测系的9个性状一般配合力(GCA)效应均存在极显著差异(P<0.01),其中以T2的鲜穗重、每穗粒重、播种至散粉天数、播种至吐丝天数、南方锈病病情等级、穗位系数、株高、穗位高和品质GCA效应最优,其在春播中分别为7.93、10.55、10.56、11.82、-33.37、-13.51、24.45、4.82和2.92,在秋播中分别为21.75、24.21、10.56、11.82、-23.36、-9.39、14.19、3.23和2.17,各性状在春播和秋播中均表现相对稳定,利用该自交系配制优质、高产组合的可能性较大,其他自交系不同性状GCA效应表现各异;杂交组合W150×T2的每穗粒重、南方锈病病情等级和品质特殊配合力(SCA)效应在春播中分别排名第1、2和4位,在秋播中分别排名第1、7和1位,杂交组合BN2RH×T2春播分别排第6、3和1位,秋播时分别排名第4、1和4位。【结论】被测系T2在品质、南方锈病病情等级及产量相关性状均表现较优,具有较高的育种潜力,其他被测系需根据本地的生态特性和育种目标进行遗传改良;W150×T2和BN2RH×T2为苗头组合,表现出高产、优质和抗南方锈病的特点,可进一步参加品种比较试验和区域试验。

【Objective】In the present study,the combining ability and genetic parameters of different waxy maize inbred lines were investigated,in order to provide guidance for improving breeding efficiency of waxy maize.【Method】Ten waxy maize inbred lines were set as tested lines,and five waxy maize inbred lines were set as testers.NCII genetic design was adopted to arrange50hybrid combinations.The combining ability and genetic parameters of their quality,disease level of southern corn rust level and yield-related traits(fresh weight,grain weight per ear,days from sowing to shedding,days from sowing to silkinig,plant height,ear height,ear height coefficient)were analyzed.【Result】The results showed that the general combining ability(GCA)of the nine traits among the10tested lines was significantly different(P<0.01).GCA of T2were7.93(fresh weight),10.55(grain weight per ear),10.56(days from sowing to shedding),11.82(days from sowing to silking),-33.37(southern corn rust),-13.51(ear height coefficient),24.45(plant height),4.82(ear height),2.92(quality)at spring sowing,and21.75(fresh weight),24.21(grain weight per plant),10.56(days from sowing to shedding),11.82(days from sowing to silking),-23.36(southern corn rust),-9.39(ear height coefficient),14.19(plant height),3.23(ear height),2.17(quality)at autumn sowing.The traits of T2were stable at spring sowing and autumn sowing.Therefore,it was very likely to breed quality and high-yield combination with T2.While the performance of other inbred lines varied with different traits.The specific combining ability(SCA)of grain weight per ear,disease level of southern corn rust,and quality for hybrid combination W150×T2ranked the first,second and fourth at spring sowing,and the first,seventh and first at autumn sowing;and BN2RH×T2ranked the sixth,third and first at spring sowing and the fourth,first and fourth at autumn sowing.【Conclusion】The tested line T2has great potential since its sound performance in quality,disease level of southern corn rust and yield-related traits.Other tested lines need to be genetically improved based on local ecological characters and breeding targets.W150×T2and BN2RH×T2is the most valuable combination with high yield,good quality and resistance to southern corn rust.It can be applied in variety comparative test and regional test in the future.