Mating System and Reproductive Strategy of Leymus racemosus

The mating system of Leymus racemosus was studied from aspects of flower design,flower display,pollen viability,duration of stigma receptivity and mating mode.The results are as follows:The asynchronous dehiscing of three anthers in one floret can elongate the pollen viability.The feature that pinnate stigma is delivered out of lemma and palea to receive exotic pollens after three anthers having dispersed the pollens not only can avoid the sexual interference in one single floret,but also can decrease the interference caused by geitonogamous pollens on stigmas in combination with that florets in the same inflorescence open in the way of stage and mass.It is concluded that L.racemosus is not only incompatibility of self-pollination but also incompatibility of geitonogamous pollination.During the process of long adaptation to the desert environment,L.racemosus has evolved unique characteristics of flower design and flower display as well as short pollen longevity and so on to promote cross-pollination.