Preliminary Study Of The Real Endangered (pest Stomach) Mechanism

A Preliminary Study on endangered mechanism of Kolkwitzia amabiis Graebn. Abstract Kollcwitzia amabilis Graebn. is one of individual genera plants endemic to China. It was listed in Third class protected plants of China. In this paper, a broad literature has been reviewed concerning its community type, seeds characteristics, embryo sacs development and genetic variability. The results shown that 1 .It is resistant to drought and barrenness. It can adapt to different conditions and is not strict with ecological environment. 2.Worse seeds quality, much lower germination rate and longer time of after ripening in a natural state are weak points of sexual reproduction. The transformation from seeds to seedlings is the main threat to this species. 3.Ovules were antropous, unitegmic and tenuinucellate. The tetrad of megaspores was linear shaped, with the first cell from the cbalazed end being functional. The development of embryo sacs belongs to the polygonum. Many ovules are sterile. 4.Genetic variation level was determined for different population; allele variation at 6 loci was determined for 3 enzyme systems. There were relative genetic variability within population and not very high. a On these bases, causes of its endangered state were summarized. Some protective measures have been put forward.