孕穗期低温对高粱花药解剖结构的影响

在人工气候箱内低温处理孕穗高粱植株，处理后用卡诺液固定花药，石蜡切片，研究低温造成高粱障碍型冷害的结构机制。结果表明，高粱障碍型冷害的结构机制表现为３种花药结构异常类型：Ａ．花粉母细胞与绒毡层分离；Ｂ．部分绒毡层细胞变形，细胞间距加大；Ｃ．线毡层与药壁组织分离。此外，低温处理使绒毡层提前消失的同时，小孢子受害。高粱的低温敏感时期从花药结构异常判断，花粉母细胞减数分裂前期Ⅰ，中期Ⅰ以及四分体期对低温敏感。

EFFEET OF CHILLING TREATMENT AT EAR BEARING STAGE ON THE STRUCTURE OF ANTHER IN SORGHUM

Sorghum at the car bearing stage was treated with low temperature in plant growth chamber to investate the effect of low temperature on anther structre.The results showed that the struetural mecnanism of sterile-type cooling irjury insorghum was different from that in rice.there were three kinds of abnormal stuctures of polle sac in sorghum instead of tapetal hypertrophy found in rice.They are as follows:First,There was space between tapetum and microspore mother colls.Second,the space among tapetalcells was enlarged.Third,there was space between tapetaum,and pollen sae wall.In oddtion,after cooling treatment,the tapetum disappeared ahead of time and microspores were damaged.The proportion of abnormal pollen sae showed that sorghum was sensitive to low temperature at prophase I and motaphase I in meicsis and tetrad period.