%A JIN Shu-Rong,WANG Yan-Mei,CHANG Yue,WANG Yue-Hua,LI Jia-Na,NI Yu %T Activity and gene family expression of β-amylase in Brassica napus differing in harvest index %0 Journal Article %D 2019 %J Acta Agronomica Sinica %R 10.3724/SP.J.1006.2019.94001 %P 1279-1285 %V 45 %N 8 %U {https://zwxb.chinacrops.org/CN/abstract/article_6746.shtml} %8 2019-08-12 %X

The transferring efficiency of photosynthate from source organs to grains is the key process to increase the harvest index in Brassica napus, and amylase activity in source organs affects the transport intensity of assimilates to grains. The relationship between β-amylase (BAM) and the formation of high harvest index in rapeseed had not been clear. In this study, three different inbred lines, high-yield and high-harvest index rapeseed, high-yield and low-harvest index rapeseed, and low-yield and low-harvest index rapeseed were selected, and stem, leaf, silique pericarp and seed were sampled at 5, 10, 15, 20, and 25 d after the final flowering to analyze the activity of β-amylase and the expression level of its gene family members. The activity of β-amylase increased with the development of source organs. The activity of β-amylase in leaves and silique pericarps of high-harvest index rapeseed was significantly higher than that of low-harvest index rapeseed. In the β-amylase gene family, the expression of BAM1, BAM4, and BAM5 in the stem, leaf and silique pericarp of rapeseed increased with the development of organs. At 25 d after the final flowering, the expression of BAM1 and BAM3 in leaves and silique pericarps of high-harvest index rapeseed was significantly higher than that of low harvest index rapeseed. The expression of BAM4 and BAM5 in the silique pericarps of rapeseed with high harvest index was significantly higher than that of rapeseed with low harvest index at 15 d and 20 d after the final flowering. Taken together, BAM1 and BAM3 may enhance the transport intensity of photosynthate to grains by promoting starch degradation in leaves and silique pericarps in rapeseed with high harvest index, and BAM4 and BAM5 may regulate the transport of photosynthate to grains mainly by acting on starch degradation in silique pericarps. BAM4 and BAM5 may also be involved in the regulation of starch in rapeseed seeds.