Study On Relationship Between Endogenous Hormones And Pod-length Development In Brassica Napus

A group of resynthesized long-pod Brassica napus lines were developed by the Rapeseed Research Center, Sichuan Agricultural University. In this paper, lines of different pod length including two specially-long pod lines H218 ,H203, two normal pod length lines MSP334, Zhongyou 821 and two short pod lines"4101"and Zeng 11, were exploited as experimental materials to study the relationship between endogenous hormones level and the pod length development. The main results were as follows:1. By comparing pod lengths from the lrt day to the 20th day after blossom, we thought that the different development rate of pods from the 1rt day to the 20th day determined the final pod-length distinction in these materials. The pod lengths of different materials on the lrt, the 5th, the 10th, the 15th, the 20th day had significant differences at 0.01 level, respectively. This showed that pod lengths in different development periods represented the pod lengths in different type of materials.2. It was shown from the variance analysis, the absolute contents of endogenous IAA, GA₃, iPA, ABA in different materials had significant differences at 0.01 level. The absolute contents of endogenous hormones had the overall trend, that was, the contents of all the endogenous hormones reached the maximum on the lrt day, and then declined after 1 day. The differences of the absolute contents of endogenous hormones in different type of materials were indistinct. Correlation analysis results showed that IAA contents on the 5th day and the 20th day, iPA contents on the 1rt and the 10th day, GA₃ content on the 5th day and ABA content on the 5th day, could be related to the final pod-length development.3. It was shown from the dynamic change in relative contents of endogenous hormones that, IAA contents of specially-long pod lines were notably lower than those of the short pod lines on the lrt and the 5th day; iPA contents of the specially-long pod lines were notably lower than those of the short pod lines on the 5th, the 10th, the 15th and the 20th...