中文摘要：

在自然种群中对木地肤的开花物候、开花动态进行观察,用MTT法测定了木地肤单花花粉的活力及其柱头的可授性。结果表明,木地肤生殖枝穗状花序的开花顺序是：中上部→下部→顶部,叶腋聚头状花序的开放顺序是：中央小花→外轮小花;木地肤单花花期分为雌性亚期和雄性亚期,雌性亚期10-12d,雄性亚期1d;木地肤有红黄两种颜色柱头,雄蕊有红黄两种颜色花药,自然种群中花有4种不同的柱头花药组合类型;木地肤的花粉活力在盛花期〉80%,4-8h内花粉活力最高,之后活力明显下降,黄色花药的花粉寿命（8h）长于红色花药内花粉寿命（4h）;木地肤红色和黄色柱头的可授性变化趋势一致,柱头在刚露出花被片时就具有可授性,并随柱头生长持续加强,在第8-12天时可授性最强,柱头可授期长达12d,占单花花期的92.3%;P/O（花粉/胚珠）比值为61900-64200,属于异交繁育系统。对开花动态与花粉活力及柱头可授性的研究将为探讨其繁育系统进化及生态适应机制提供科学依据,并为新疆荒漠地区饲用半灌木良种的繁育提供基础资料。

英文摘要：

Kochia prostrata is subshrub of Chenopodiaceae and fine pasture inhabiting arid zone.Flowering phenology,flowering dynamic,pollen viability and stigma receptivity of K.prostrata were studied.For spicate inflorescence of K.prostrata middle flowers bloomed first,then lower flowers,the upper flowers bloomed at last.For a poly-capitulum,central florets bloomed earlier than bilateral ones.The flowering course of single flower of this species can be divided into female subage and male subage.The female subage can lasted 10 to 12days and the male subage was 1day.This species produces two types stigmas and anthers in colour（red and yellow）.There are four combination types of stigma and anther in the K.prostratapopulation.The pollen viability of K.prostrata was highest at initial stage（〉80%）,higher on the 4to 8hours after flowering,and then reduced evidently.The pollen viability of yellow-anthers are longer than the red-stigmas.The change tendency of receptivity of the two colour stigmas is similar.The stigma receptivity appeared on the first day of stigma showing from tepals,and then enhanced with the growth of stigma.The stigma receptivity were highest on the8 to 12days after flowering.The period of stigma receptivity was about 12 days,account for 92.3%of single flower blooming.The pollen-ovule ratio（P/O）of K.prostrata was 61900-64200.Based on Cruden＇s criterion,the breeding system would be outcross.Floral dynamics,pollen viability and stigma receptivity have significant value to understanding the evolution of breeding system and the ecological adaptive mechanism.