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对中间偃麦草(E.intermedia)和长穗偃麦草(E.elongat)的杂交种F_1的幼穗分化和小孢子发育进行了观察。结果表明,杂种F_1幼穗分化是一个连续的过程,可分为8个时期:初生期、伸长期、结节期、小穗突起期、颖片突起期、小花突起期、雌雄蕊形成期和抽穗始期。杂种F_1生长锥的分化具有很强的规律性:中上部的小穗最先发育,然后从中上部开始逐渐向上、向下发育,基部的小穗发育最缓慢;在每一小穗上,基部的小花最先发育,然后由基部逐渐向上发育。杂种F_1小孢子发育是一个连续分化的过程,在小孢子发育过程中有些细胞有没配对的染色体存在,有染色体粘连现象出现,在减数分裂中期Ⅰ染色体以二价体为主,但能观察到少量单价体、三价体和四价体的存在。
Spike differentiation and microspore development of F1 hybrids between E.intermedia and E. elongat were observed. The results showed that spikelet differentiation of hybrid F_1 was a continuous process and could be divided into eight stages: primordial stage, elongation stage, nodule stage, spikelet stage, glume stage, floret stage, pistil and stamen formation stage Ear of heading. The differentiation of hybrid F_1 growth cone has a strong regularity: the spikelet in the middle and upper part developed first, and then gradually upward and downward from the middle and upper part, and the spikelet developed at the base was the slowest; on each spikelet, the base Floret first developed, and then gradually from the base upward development. Hybrid F1 microspore development is a process of continuous differentiation. During the microspore development, some cells have unpaired chromosomes and chromosomal adhesions appear. During meiotic metaphase, chromosome I is predominantly divalent, but can be observed To a small amount of monovalent, trivalent and tetravalent existence.