四川穗状核桃雌花芽生长发育的研究

为探索穗状核桃雌花产生多花多果的现象,发掘四川核桃的特异种质资源,通过形态比较、石蜡切片和电镜扫描等方法,比较了穗状核桃优良资源的雌花芽生长发育特点。结果表明:(1)雌花芽着生方式分为呈聚生或散生,HSLH为串状结果,HSZML、CTYM和SQLG为穗状结果。(2)HSZML雌花芽、顶芽均为最大;SQLG雌花芽、顶芽均为最小。(3)3月上旬,雌花芽开始萌动,生长点顶端凸起,HSZML、CTYM和SQLG分化出不同方向的雌蕊原基;5月上旬,生长点向上生长,分化出多个叶原基,CTYM和SQLG顶端生长点逐渐伸长,形成雌花原基;7月下旬,CTYM和SQLG继续伸长生长;10月上旬,HSLH和SQLG已分化出4个雌花原基,HSZML和CTYM已分化出3个雌花原基。

A Study of the Growth and Development of Female Flower Buds of Spikes of Walnuts in Sichuan

In order to further explore the phenomenon that female flowers of spikes of walnuts produced more flowers and fruits and the special germplasm resources of Sichuan walnut were excavated, Studies were made of excellent resources of spikes of walnuts in early stage, the growth and development characteristics of female flower buds of spikes of walnuts by use of morphological comparison, paraffin section and electron microscope scanning.The results showed that :(1)Female flower buds were clustered or scattered, HSLH formed string fruits, HSZML, CTYM and SQLG formed spike-like fruits.(2) HSZML had the largest female flower buds and apical buds, while SQLG had the smallest female flower buds and apical buds.(3) In early March, female flower buds began to germinate and the apex of growth points was raised, HSZML, CTYM and SQLG differentiated into pistil primordia in different directions. In early May, the growth points grew upward and differentiated into multiple leaf primordia. The top growth points of CTYM and SQLG gradually elongated to form the primordium of female inflorescence. In late July, CTYM and SQLG continued to elongate. In early October, four primordia of female inflorescence were differentiated from HSLH and SQLG, and three primordia of female inflorescence were differentiated from HSZML and CTYM.