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光照环境对营养生长存在明显影响已经是不争的事实,但光照影响器官的效应必然会引起生殖性状的反应,尤其是雌性适合度表达。本文利用麻疯树林分乔木林遮光与否的对比,研究遮光对麻疯树构件水平上营养器官与生殖器官的影响,探究光照对雌花数量与性比影响的本质问题。结果如下:(1)倮果桥林下麻疯树雌花数量频度分布偏左,平均为2.716 0/支±3.3052/支,而林外频度分布偏右,平均为5.0417/支±4.4106/支,二者差异极为明显;(2)倮果桥林下性比频度分布偏左,平均为0.0278/支±0.0215/支,而林外麻疯树性比频度分布偏右,平均为0.0378/支±0.0738/支,二者存在显著差异;(3)林下构件直径频度分布偏左,平均为0.8112 cm±0.1973 cm,而林外构件直径为0.9125 cm±0.2809 cm,频度分布偏右,林外与林外构件直径差异极为显著;(4)林下构件长度为8.3255 cm±10.057 cm,频度分布偏左,而林外构件长度为18.548 cm±19.3817 cm,构件枝长在林下与林外存在极显著差异。乔木林遮光使得麻疯树雌花分化数量与性比偏低,频度分布偏左,表明光照降低了麻疯树的雌花分化能力。进一步分析表明,雌花分化能力降低与构件大小减小有关,表明光资源限制通过降低营养器官生长量进而实现对雌花分化的影响与调节。 相似文献
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Yasuyuki Onodera Itaru Yonaha Satoshi Niikura Seishi Yamazaki Tetsuo Mikami 《Scientia Horticulturae》2008,118(3):266-269
Two cosexual spinach lines, 03-336 and 03-258, were examined to investigate their sex expression. We found that line 03-336 consisted of plants bearing both pistillate and staminate flowers on the same individual (strictly monoecious type), while line 03-258 consisted of plants with both pistillate and hermaphroditic flowers on the same individual (gynomonoecious type). Interestingly, the two lines exhibited distinct patterns of inheritance when crossed with the pistillate plants derived from a dioecious line. The strictly monoecious character was considered to be conditioned by the known allele Xm, whereas the gynomonoecious character appeared to be governed by a novel monoecious allele or modifying gene(s) that may affect the sex expression. 相似文献
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Colonisation plays a central role in both the initial occupancy of a region through range expansions as well as in metapopulations,
where local extinctions are balanced by re-colonisations. In this paper, we review the effects that colonisation is expected
to have on patterns of genetic variation within a species, and we draw attention to the possibility of interpreting these
patterns as signatures of colonisation in the past. We briefly review theoretical predictions for the effect of colonisation
on both neutral genetic diversity and on variation at genetic loci that regulate the sexual system of plant populations. The
sexual system represents a particularly important trait in this context because it is affected by both selection during colonisation,
and because it influences gene flow amongst populations. Finally, we introduce four case studies of plant species that show
variation in their sexual systems that is consistent with theoretical predictions. 相似文献
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