光照时间对水蔗草兼性无融合生殖的影响

Influence of Photoperiod on Facultative Apomixis in Apluda mutica

摘要:

在水蔗草花序发育期间给予不同时间的光照处理后,对其花粉育性、结实率和无融合生殖频率的研究表明:(1)花粉育性在不同光照时间下无显著差异。(2)减少1 h和2 h光照时间的结实率和对照相比无明显变化。(3)增加1 h和2 h光照时间,花序发育受到抑制,抽穗延迟,只有极少数花序发育成熟,产生的种子很少。(4)在自然光照时间和增加1 h光照时间条件下,无融合生殖的频率在0.41-0.64之间;在减少1 h和2 h及增加2 h的光照条件下,无融合生殖的频率在0.19-0.22之间,和对照及增加1 h光照处理相比,无融合生殖频率显著下降。

Abstract:

Pollen fertility, seed-set and incidence of apomictic and sexual embryo sacs in Apluda mutica under different photoperiods were investigated. There were no differences in pollen fertility between treated and untreated plants. No difference in the rate of seed-setting was found between decreasing photoperiods and natural photoperiod. Flowering and seed-setting were retarded greatly as photoperiod was greater than natural photoperiod during inflorescence development. Frequency of apomixis was from 0.41 to 0.64 when the plant was exposed to natural photoperiod, and to that with addition of one hour. The frequency of apomixis reduced to 0.19-0.22 if natural photoperiod was decreased by 1 or 2 hours, or increased by 2 hours, showing that the frequency of apomixis was greatly reduced as compared to the control or to the condition of natural photoperiod with one hour increase.