Intraspecific variation in floral organs and structure in Brassica rapa L. analyzed by principal component analysis.

摘要

Four inbred parental lines of some F1 hybrids, which become genetically homogeneous through 5 to 7 generations of self-crossing, and 30 cultivars that represented high genetic variability across 8 varietal groups of B. rapa [B. campestris] were used to investigate intraspecific variation in the following floral characteristics: long stamen length (LSL), short stamen length (SSL), long anther length (LAL), short anther length (SAL), ovary length (OL), stigma height (SH), stigma width (SW) and style length (SL). Data were analysed by principal component analysis. There were large differences in the floral characteristics among lines and cultivars. The floral characteristics could be divided into 2 groups (stamen vs. pistil). One group consisted of the stamen (LSL, SSL) and anther (LAL, SAL), while the other consisted of ovary (OL), stigma (SH, SW) and style (SL). The most remarkable variations were apparent in the female organs, especially SL. That is, scores of the coefficient of variation for the female organs were relatively higher than those for the male organs. The contribution of the first 4 principal components was very high and accounted for as much as 68% of the total variation..