调查了564份水稻材料的柱头外露率,测量了其中部分材料的外露柱头长度和宽度。19份野生稻柱头都外露,其中17份外露率高,最高为100%,外露柱头长,最长达2.6mm,表明柱头外露是稻属的一种原始性状。中、高纬地区的粳稻育成品种中,柱头全不外露的较多,有些柱头虽外露,但外露率低,外露的柱头短。我国中、低纬地区的早籼也是这样。云南的地方品种中柱头外露的多,而且外露率高、外露柱头长。云南地方品种的这种原始性状,看来也可作为云南是稻种起源中心之一的旁证。 The stigma exsertion rate of 564 rice materials was investigated and the length and width of exposed stigma of some of the materials were measured. Nineteen wild rice stigmas were exposed, of which 17 had high exsertion rates of up to 100%. Exserted stigmas were long and up to 2.6 mm in length, indicating that stigma exposure is a primitive trait of the genus Oryza. In middle and high latitude japonica rice breeding varieties, stigmas are not exposed more, while some stigma although exposed, but the exposure rate is low, exposed stigma short. The same applies to the early Indica rice in China’s low and medium latitudes. Yunnan local varieties in the stigma exposed more, and the high rate of exposure, exposed stigma long. This primitive trait of Yunnan local breeds also seems to serve as a proof that Yunnan is one of the centers of origin of rice breeds.