3作物的需水关键期寻求作物的需水关键期，是非充分灌溉要解决的主要问题。作物对水分的敏感度指标集中体现了作物需水关键期的大小顺序。目前国内利用国外的计算模型已计算出不少作物的敏感度指标，但大部分没有搞过专门试验，只是采用以前的一般灌溉试验资料，计算出的敏感度 3 Crop water demand Critical period The critical period of water demand for crops is the main problem to be solved by inadequate irrigation. The indicators of crop moisture sensitivity focus on the critical sequence of crop water requirements. At present, the calculation models of foreign countries have been used to calculate the sensitivity index of many crops. However, most of them did not engage in specialized tests and only used the previous general irrigation test data to calculate the sensitivity