小麦的粒重是构成产量的重要因素之一,在亩穗数50万,平均穗粒数30粒,千粒重30克左右的情况下,千粒重若增加1克,每亩可增产30斤左右。在北京条件下,同一品种千粒重的变化幅度一般在28-40克之间,增产潜力很大,尤其是高产田,亩穗数已达到一定程度,后期管理除创造开花、授粉的有利条件以保证穗粒数外,特别要创造灌浆的有利条件以争取粒重。一、小麦雌雄蕊的发育及开花受精结实小麦一朵花有三个雄蕊、一个雌蕊。雄蕊包括花丝和花药两部分,每个花药具有4个花粉囊。当雄蕊发育到一定时期,花粉囊中产生多数花粉粒,花粉粒发育成熟时,里面产生两个精子;雌蕊由柱头和子房两部分组成,在子房发育过程中,里面产生一个胚珠,胚珠发育成熟时,珠心内出现含有8个细胞的胚囊,其中有 The grain weight of wheat is one of the important factors that make up the yield. If the number of ears per acre is 500,000, the average number of grains per ear is 30, and the weight of thousand grains is about 30 grams, if the grain weight is increased by 1g, the yield per acre can be increased by 30kg. Under Beijing conditions, the variation range of 1000-grain weight of the same variety is generally between 28 and 40 grams, and the potential for yield increase is great. Especially in high-yield fields, the number of ears per mu has reached a certain level. In addition to the favorable conditions for creating flowering and pollination in later management, In addition to the number of grains, it is particularly important to create favorable conditions for grain filling for grain weight. First, the development of wheat stamens and flowering fertilized wheat one flower has three stamens, a pistil. Stamens include filaments and anthers two parts, each anther has four pollen sac. When the stamens develop to a certain period, most pollen grains are produced in the pollen sacs. When the pollen grains mature, two sperm are produced inside. The pistil consists of stigma and ovary. During ovary development, an ovule and ovule are developed At maturity, the embryo sac containing 8 cells appears inside the beads, among them