The difficult problem that still awaits an answer is how to get higher yields from food crops without a commensurate rise in the loss of water through evapotranspiration.

困难的问题是，仍在等待怎样获得与蒸散而损失的水相对应的食用作物产出。

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Potassium dihydrogen phosphate promoted the opening of stomates so as to increase evapotranspiration intensity and relative water loss rate.

磷酸二氢钾有促进气孔开张的作用，使蒸腾强度和相对失水率相应增大。

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