品种与栽培大豆在长期的自然选择与人工选择过程中形成了生育期长短不同的生态类型。生育期短的早熟种之所以早熟,是由于它的营养生K期短,即从出苗至开花的时间短(35～40天).从始花至终花的时间和拉片时间也短,开花后不久即陆续结荚鼓粒,但鼓粒的时间并不短,大约开花后60～65天左右才能成熟。晚熟品种之所以晚熟,是由于它从出苗到开花的时间长,一般出苗后60～65天才开花,从开花至成熟大约70～75天。开花至出现嫩荚和拉片所需时间比早熟种长,但鼓粒灌浆时间与早熟 Varieties and cultivated soybean in the long-term natural selection and artificial selection process of the formation of a different type of ecological life of different types. Early maturity of the short maturity of the reason why the early maturity is due to its nutritional K short, that is, from emergence to flowering time is short (35 to 40 days) from beginning to end flowers and pull the time is also short, Not long after the flowering pod drums one after another, but the drum of time is not short, about 60 to 65 days after flowering to mature. The reason why late-maturing varieties late maturity, because it is from emergence to flowering time is long, generally 60 to 65 days after emergence of flowering, from flowering to maturity of about 70 to 75 days. The time required for flowering to appear tender pods and pull-tabs is longer than that of precocious ones, but the time of drum grain filling is precocious