中综3号玉米群体格子混合选择效果分析

Effects of Grid Mass Selection in ZZ3 Maize Population

用格子混合选择法完成了对中综 3号玉米群体 6轮混合选择 ,并用 5个测验种对 C0 、 C2 、 C4 和C6进行 NC 交配。经过 1995、 1996年对测交后代的 2年 3点鉴定 ,结果表明 :中综 3号与 5个测验种的测交组合产量均逐轮提高。经 6轮选择后 ,群体籽粒产量每公顷增加了 1155( 2 4 .0 5% ) kg,平均每轮增加192 ( 4 .0 1% ) kg。产量的一般配合力从 C0 的 - 55.87提高到 C6的 61.0 1。同时 ,穗长、行粒数、千粒重的一般配合力均得到了显著提高。说明中综 3号产量的改良、配合力的提高 ,是穗部性状得到了综合改良的结果。中综 3号群体与 5个测验种的杂种优势均得到显著改良。在产量性状配合力得到改良的同时 ,中综 3号株高。

Six cycles of grid mass selection for grain yield and correlated traits have been conducted in Zhongzong No.3 (ZZ3) population. The C 0、 C 2、 C 4 and C 6 populations were crossed with five testings in 1994. The 20 tested combinings were evaluated in 1995 and 1996 at three locations. The results showed that the average gain for grain yield per cycle of ZZ3 was 192kg (4.01%). The general combining ability (GCA) for grain yield was increased from -55.87 of C 0 to 66.01 of C 6, and the GCA for ear length, No.of kernels/row and 1000 kernel wt. were increased significantly as well. The heterosis between improved ZZ3 population and five testings increased significantly as the cycle developed. The GCA for grain yield had associated with the increase of the GCA for plant height and ear height.