Studies On The Pollination Biology Of Pugionium Cornutum(L.)

This paper focused on and evaluated the pollination characteristics of P. Cornutum in natural habitat and cultivated population. By field investigation and lab experiment, from 2004 to 2006, the main purposes of this study are to reveal the pollination characteristics of P. Cornutum, to find out the effect of pollination process on the propagation and development of P. Cornutum. Following are the results:1) P.cornutum is in blooming on June 25-July 30, a flower is blooming during 3-4d, an entire plant in about 25d,and the population in 25d.P.cornutum reaches its full boom in 18:00-20:00 in the desert,and 15:00-18:00 on the campus.2) Pollen germination characteristic of p.cornutum was evaluated by pollen culture media test ,its stigma receptivity was estimated by emasculation ,bagged, hand cross-pollination and benzidine-H2O2 method .The results as follows: the pollen of p.cornutum germinating percentage reached the highest on the media supplemented with 20% sucrose and 0.001% Boric acid; the most congenial temperature of pollen germination is 25℃,and effective temperature is 15℃-38℃;The pollen can reach highest peak from the biggest white flower bud to 16h after blooming; low temperature(4℃) is advantage to the storage of pollen. The stigma of p.cornutum had receptivity from 48h before blooming to 96h after blooming. 3) P.cornutum should be a kind of a kind of cross-pollinating and entomophilies plant without capability of selfing by the total value of OCI ,the value of P/0, and the experimentation of bagged so on. 4) Wind is very weak during pollinating for P.cornutum. Investigation showed that there are 19 species flower visiting insect in maowusu sand,which belong to 14 families and 5 orders. There are 12 species flower visiting insect on the campus, which belong to 9 families and 5 orders. Among them, Apis mellifera, Bombus sp.,Episyrphus balteatus and Pseudouolue ella mimica are the main mutual of the two group. Bombus sp.is the highest frequency of flower visiting insects in maowusu sand. Apis mellifera and Episyrphus balteatus are the highest frequency of flower visiting insect on the campus. 5) During the sexual reproduction, Tapetum was the secretory type. The cytokinesis of the microspore mother cell was of the successive type. The microspore tetrads were tetrahedron. The bud length is 1.5mm in the microspore tetrads. Each locule contained the two ovule. The mature ovules were curve and thick-nucellus.