| hrough two-year potted experiment, study was made on the soil water status around crop rootzone, photosynthetic rate, transpiration rate, water use efficiency, yield and quality under water-controlled partial wetting irrigation and drip irrigation without covering.The results showed that the evaporation capacity under water-controlled partial wetting irrigation was obviously less than drip irrigation;moreover, the yield of leaf lettuce under it was higher than drip irrigation.The water-controlled partial wetting irrigation has the highest water use efficiency (reached 42.42 kg/m3) , which was more than drip irrigation (just 15.14 kg/m3) .The photosynthetic rate and transpiration rate showed a split-blip curve among all treatments, and displayed a trend of treatment 1 > treatment 2 > treatment 3 > treatment 4.The root/shoot of leaf lettuce under water-controlled partial wetting irrigation (0.187) was also higher than drip irrigation (0.071) .The ascorbic acid content of water-controlled partial wetting irrigation treatment reached 14.62 mg/100g, and the drip irrigation treatment was only 12.82 mg/100g.The results all indicated that water-controlled partial wetting irrigation can improve the distribution of photosynthetic product in leaf lettuce, harmonize the relationship between roots and shoot, increase water use efficiency, and unify the yield and quality of leaf lettuce. |