回交次數稉秈稻雜種後裔稔實率及株高與育種選拔率之影響

Abstract

為了將秈稻優良特性引進本省稉稻中，以育成優良之稉稻品種及擴展本省稉稻育種資源，以5個稉稻品種為母本，13個秈稻品種（系）為父本進行雜交，共得16組合稉秈稻雜種F1，其中四個雜種F1於第一次回交時，分別與其父母本回交，其他12個組合的第一次回交及全部（20組合）之第二、三、四次回交均以母本為輪迴親；調查16個雜種F1的稔實率、株高，與父母本回交組合之F2BC1F1、BC2F1、BC3F1的株高、稔實率及各世代選育情形，另外12組合亦在各世代進行選拔，本試驗之結果摘述如下：雜種F1的稔實率從3.57~62.21%，不稔率因組合不同而有明顯的差異。Crosses were made between 5 Japonica rice varieties (as maternal parents) and 13 Indica varieties/strains (as paternal parents) for the purpose to introduce superior charac. teristics from Indica to Japonica rice. Among the 16 F1 hybrids obtained, 4 were backcrossed to both their paternal and maternal parents. The resulted 8 BC1 and the remaining 12 F1 were backcrossed for 1 to 4 generations to their respective maternal parent (as recurrent parents). The fertility rate and plant height were investigated on all the F1, F2, BC1F1, BC2F1, and BC3F1 offsprings. Experimental results indicated that fertility rate of the F1 hybrids ranged from 3.57 to 62.21%, with significant variation among combinations.