小麦的产量是由每亩穗数、每穗粒数和粒重构成的。穗数是高产的首要因素。在一定穗数范围内,增加粒数和提高粒重是小麦增产的关键。在生产中常有这样的情况:水肥条件差的小麦,穗数少,穗头也小,有些高产田,虽然穗数较多,但穗头不大。这些都是由于穗子发育不好所造成的。因此,掌握小麦穗的发育规律,加强麦田管理,促进幼穗正常发育,对于争取穗大粒多十分重要。小麦的穗子是由茎顶端的生长锥分化发育而来。一个麦穗由穗轴和小穗两部分组成。每穗有许多小穗着生在穗轴两侧。每个小穗又包括一个小穗轴、二个颖片(外颖、内颖) The yield of wheat consists of spikelets per acre, grain number per spike and grain weight. Spike number is the primary factor of high yield. In a certain range of spikes, increasing grain number and increasing grain weight are the key to increasing wheat yield. In the production of such a situation often: poor water and fertilizer conditions of wheat, fewer spikes, small heads, some high yield fields, although more spikes, but small head. These are caused by poorly developed ears. Therefore, mastering the law of wheat ear development, strengthening wheat field management, and promoting the normal development of young spike, for the spike large grain is very important. The ear of wheat is derived from the differentiation of the growth cone at the top of the stem. A wheat ear by the cob and spikelet of two parts. There are many spikelets per ear on both sides of the cob. Each spikelet also includes a rachilla, two glumes (external Ying, Ying)