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冰草茎生长锥分化、幼穗的形成以及花粉母细胞减数分裂过程与结实器官的形成和产量性状密切相关。生长锥分化是一个连续的过程,可分为初生期、伸长期、结荚期、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8个时期。幼穗的发育规律性也很强,花序中上部的小穗最先发育,然后向上、向下顺序进行,基部小穗最后发育;小穗则是基部小花先发育,然后向上顺序进行。小孢子减数分裂发生在抽穗期,染色体在形态结构和行为表现上的特征是:中期Ⅰ染色体配对比较规则,大多形成二价体,并具有1～4个四倍体,少数细胞中具三价体和单价体;除具28个正常数日的染色体外,大多数细胞中还具有1～2个超数染色体;在分裂的后期和末期有落后染色体和染色体桥出现,二分体和四分体时期可观察到微核。
The growth cone differentiation, spikelet formation and meiosis of pollen mother cells were closely related to the formation and yield traits of solid organs. Growth cone differentiation is a continuous process, which can be divided into eight stages, that is, the primordial stage, the elongation stage, the podding stage, the spikelet stage, the glume stage, the floret stage, the pistil formation stage and the ear initiation stage. The law of development of panicle was also very strong. The spikelets in the upper part of inflorescence developed first, and then went upwards and downwards. The spikelets developed at the base and the spikelets developed first and then went upwards. Microspore meiosis occurs at the heading stage. Chromosomes are characterized by morphological structure and behavioral manifestations: metaphase Ⅰ chromosome pairing rules, most of which form bivalents and have 1 to 4 tetraploids, and few of them have three In addition to having 28 normal days of chromosomes, most of the cells also have 1 to 2 super-chromosomes; late and late stages of division have lagging chromosomes and chromosome bridges, Micronuclei can be observed during the split phase.