Breeding System And Phenology Comparison Of Bauhinia Purpurea And Bauhinia Blakeana

In this article,the group of Bauhinia purpurea L. and group of Bauhinia blakeana Duun in Guangxi university were taken as the objects to study their flowering phenology and breeding.According the main content such as phenology,flower characteristic, stigma to teach sex detection,P/O and OCI, the two group in their four levels which are single flower, inflorescence, individual and group. Try to fig out the habit of reproductive ecological. The result of reach as follows:1. The B. purpurea groups will flowering from early October to late November, the flowering duration is 96 days long, individual plant will last 36.6d, inflorescence flowering 26.6d, and florescence of single last 3d. Wheal groups of B. blakeana will keep flowering from early October to the May next year, the flowering duration last 210d, individuals florescence last 153 d, inflorescence flowering 109.5d and single flower florescence 5.1d.The flowering span for Bauhinia blakeana Dunn is longer than Bauhinia purpurea L. either single flower or group flowers. In the Florescence of single flower, Bauhinia blakeana Dunn is more than Bauhinia purpurea L. about 2-3 days, and in the florescence of group flowers is more than half of year.2. Two kinds of Bauhinia are all having, significantly flowering patterns performance the flowering patterns performance as blossom a large number of flower and concentrated. The peak flowering data of the two don’t coincide with each other. The result of flowering synchrony and flowering intensity show that the flowering phenology of B. purpurea and B. blakeana are not the same.3. Two kinds of Bauhinia are both pistil mature earlier than the stamen. In the flower just opening period, the stigma receptivity of Bauhinia blakeana Dunn is stronger than Bauhinia purpurea L., and the average number of pollen grains is more than doubled. According to pollen-ovule ratio (P/O) and out crossing index (OCI), the breeding systems of 2 kinds of Bauhinia are both crossbreeding as main, partly self-compatible, need pollinators.4. The reasons why Bauhinia blakeana has flower but no fruit may cause of the pollen. The Bauhinia blakeana is the hybrid variety of B. purpurea and B. variegate. Which make the pollen may incompatible with its stigema and stop the progress of reproduction. According to results, preliminary inference that the possible causes of the low rate of Bauhinia fruit is pollen limit.