压砂地西瓜适宜补水量研究

Study on appropriate amount of complementary irrigation with watermelon on gravel-mulched field

在压砂地条件下研究不同补灌量对西瓜的影响.结果表明,随着补灌量的增加,西瓜生育期延长,叶面积指数增加,补水量为20 m3/666.7 m2时叶面积指数最大,为2.17,水分利用效率（WUE）在10 m3/666.7 m2~20 m3/666.7 m2较高,光合速率增加,气孔导度下降,胞间CO2浓度下降,西瓜产量增加,当补灌量增加到15 m3/666.7 m2~20 m3/666.7 m2时,产量和产值达到最大.考虑到砂田补充水分的能力有限,初步得出砂田西瓜的适宜补水量为15 m3/666.7 m2~20 m3/666.7 m2.

The studies were carried on watermelon with different amount of supplementary irrigation under gravel-mulched field condition.The results showed that with increase in the number of supplementary irrigation,watermelon reproductive period,leaf area index increased to make up for water 20 m3/666.7 m2 when the largest leaf area index（to 2.17）,WUE at higher 10～20 m3/666.7 m2.Photosynthetic rate as the amount of supplementary irrigation increased,decreased stomata conductance,intercellular CO2 concentration decreased,watermelon production,when to yield and output value reached 15～20 m3/666.7 m2 the largest.Taking into account the ability of the added moisture is limited,the preliminary draw of the appropriate water supplement in gravel-mulched field watermelon is 15～20 m3/666.7 m2.