论文部分内容阅读
某些木本植物能够在没有雄性花粉授粉的情况下形成果实或种子,这种现象称为无融合生殖或无性种子。用无融合体果实或种子进行繁殖,能够精确地复制与母本植株完全相同的个体,保持其母株的优良特性。例如核桃,其雌花不分泌花蜜,无昆虫采蜜,须靠风力传粉。核桃为雌雄同株、雌雄异花植物,但雌雄花异熟,一般雄花较雌花早开放8—15天;核桃花粉的生活力,在自然条件下不超过2—3天。因此,核桃植株自花授粉是罕见的。国外学者发现,在很远距离各自生长的孤立木核桃树,能够很好结实。为了证实核桃在无雄性花粉条件下可以形成果实,核桃育种学家在格鲁吉亚东部,选择两株30年生和两株100年生的实生核桃树进行试验。这些树雄花开放后8—15天雌花形成,同株核桃树不能授
Some woody plants can form fruit or seeds without the pollination of male pollen, a phenomenon known as apomixis or vegetative seeds. Breeding with apomixis fruits or seeds allows for the exact duplication of individuals that are identical to the parent plant, maintaining the superior characteristics of their parent plant. For example, walnuts, the female flowers do not secrete nectar, no insects and honey, pollination by wind. Walnut is monoecious, dioecious plants, but male and female flowers different, generally male flowers open 8-15 days earlier than female flowers; walnut pollen viability, under natural conditions no more than 2-3 days. Therefore, self-pollination of walnut plants is rare. Foreign scholars have found that isolated wood walnut trees that grow very far away from each other can be very strong. To confirm that walnut can form fruit in the absence of male pollen, walnut breeders selected two 30-year-old and two 100-year-old native walnut trees in eastern Georgia. 8-15 days after the opening of these trees male flower female flower formation, the same strain of walnut can not grant