Aseptic micropropagation of Rhododendron P.J.M. hybrids

Summary

Shoot tips established in vitro better than single nodes. Five-cm shoot tips gave better Stage I results than 2-cm shoot tips. The best microshoot proliferation rates were obtained with isopentenyladenine (2iP) at 5 and 10 mg l^?1; tetrahydropyranyl-benzyladenine was ineffective. Microshoots rooted well, regardless of the level of 2iP in the Stage II medium. Stem-cutting-macropropagated plants generally were more variable in height, had less basal branching and were more erect than plants from microculture.     

CPPU对普通丝瓜单性结实的影响

长江中下游地区冬、春保护地栽培条件下,部分极早熟普通丝瓜的雄花比雌花晚10—20d开放,由于缺乏昆虫辅助授粉,植株不能正常授粉受精,结瓜率低,从而影响早期产量和效益。     

外来花粉对普通丝瓜F_0果实发育的影响

丝瓜为葫芦科丝瓜属一年生攀缘性草本植物。我国分布有普通丝瓜〔Luffa cylindrica(L.)M.J.Roem.〕和有棱丝瓜〔Luffa acutangula(L.)Roxb.〕两个种,长江流域主要栽培普通丝瓜。丝瓜以嫩果供食用,瓜肉细腻柔软,味道鲜美,是深受人们喜爱的夏季蔬菜。实际生产中某些普通丝瓜品种的雌雄花期不完全相遇,对坐果率有一定的影响,间种少量其他品种传粉可在一定程度上提高坐果率,这对于瓜农获取更大的经济效益有重要的指导意义。但是外来花粉授粉后对普通丝瓜F0果实发育有无影响并未见报道。育种学上,由受精卵到种子发育成熟的时期即为F0。异花授…     

中国四川芭蕉属(芭蕉科)一新变种——雷波野芭蕉

描述了芭蕉属(芭蕉科)一新变种——雷波野芭蕉(Musa luteola J.L.Liu var.leiboensis J.L.Liu et Q.Luo),并绘制了形态图。新变种以其叶基部渐狭至楔形,叶柄和叶鞘两侧具纸质或干膜质的翅,花序下垂,椭圆形或卵状椭圆形,先端圆,苞片外面淡黄色或绿黄色,先端圆或钝圆,每苞片内有花二列,果序球状、近球状或椭圆状球形,果实密集与黄色野芭蕉(Musa luteola J.L.Liu)相近似,但主要又以子房具5～9钝状棱角,浆果较大,长(6.7～)8.5～11.9 cm,宽5～7.2 cm,具5～9钝状棱角,果梗较长1～1.5 cm而有显著区别。