红菜薹产量构成因素的研究

Study on Yield Components of Hong Cai Tai (Brassia campostris  ssp)

以红菜薹（ＢｒａｓｉｃａｃａｍｐｏｓｔｒｉｓｓｐｃｈｉｎｅｎｓｉｓｖａｒｐｕｒｐｕｒｅａＨｏｒｔ）１９个基因型为试材，进行了产量构成因素的通径系数和决定系数分析。结果表明：侧薹数、侧薹重和孙薹数等三个性状对单株产量的直接效应为正作用，三者之间相互的间接效应又能加强这种正作用，它们的决定系数均较大；孙薹重对单株产量的直接效应同它与单株产量的相关存在正负不一的矛盾，它的决定系数也较小；现蕾期对单株产量只有很微弱的负作用，其决定系数也较小。因此，在育种实践中，侧薹数、侧薹重和孙薹数可作为红菜薹丰产育种选择的副性状，而孙薹重和现蕾期则不宜作为红菜薹丰产育种选择的副性状。

Path coefficient analysis and determination coefficient analysis of yield components were done with 19 genetypes of Hong Cai Tai (Brassica campostris  ssp chinensis var purpurea Hort). The results showed: Among five yield components, number of secondary branch, weight of secondary branch and number of third branch had positive direct effect on yield per plant, the indirect effect on each other increased their positive effect, and their determination coefficients were greater. Positive direct effect of third branch contradicted its negative correlation with yield per plant, and its determination coefficient was smaller. Days to budding had very small and negative direct effect and its determination coefficient was small too. In selection breed for yield, number of secondary branch, weight of secondary branch and number of third branch can be used as associate characters, but weight of third branch and days to budding cannot.