甜玉米自交系作测验种的数目选择

Studies on inbred lines of sweet corn as testers and its number

选用 9个普甜玉米 (ZeamaysL saccharataSturt)自交系作测验种 ,用新选育的 10个普甜玉米自交系作待测系 ,采用NCⅡ交配设计 ,对待测系的配合力测定中所需测验种最少数目进行研究。结果表明 ,若对测验种加以筛选 ,被筛选出的测验种只用其中 1个 ,就能够较准确地测定待测系的产量GCA (一般配合力 ) ;若对测验种不加筛选 ,则能够较准确地测定待测系的产量GCA的最少测验种数目为 3个。对 8个农艺性状进行测验种测定效果评价时 ,穗重、穗长、穗粗、行粒数、千粒重、株高及生育期对测验种的选择不太严格 ;而秃尖长对测验种的选择较严格。

The least number of inbred lines of sweet corn(Zea mays L.saccharata Sturt)needed for determining the GCA of lines to be tested was studied using 9 inbred lines of sweet corn as testers with North Carolina Design Ⅱ(NCⅡ),10 new inbred lines of sweet corn as tested lines.The results indicate that GCA effect for grain yield of inbred lines can be tested accurately by one selected tester and at least 3 testers are needed when not selecting.Its practical to use inbred lines beyond 3 as testers to estimate GCA effect for grain yield of inbred lines.Evaluating effectiveness of 8 agronomic characteristics of testers,ear weight,ear length,ear diameter,kernels per row,1000 kernels weight,plant height,and growth stages for testers selecting are not strict except bare tip length.