Alternate Infiltration Irrigation Improves Photosynthetic Characteristics and Water Use Efficiency in Mango Seedlings

Abstract

The growth status of mango (Mangifera indica L.) seedlings directly affects the yield and quality of mango, but there are few reports on water management at the growth stage of mango seedlings. The objective of this study was to identify an optimal water-saving irrigation method for mango seedlings. Taking surface drip irrigation as the control (CK), the effects of alternate infiltration irrigation (AII) on the photosynthetic characteristics, growth, and irrigation water use efficiency (IWUE) of mango seedlings were studied. The AII systems used three irrigation levels: 90% (AII90), 70% (AII70), and 50% (AII50) of the irrigation quota of CK. The results indicated that compared with CK, AII70 and AII50 increased the average leaf water use efficiency by 10.54% and 11.77%, respectively. However, compared with CK, AII50 decreased the average stomatal conductance and transpiration rate by 13.89% and 13.76%, respectively. There was a significant linear relationship between dry mass increment and net photosynthetic rate. The dynamic TOPSIS method indicated that AII70 provided optimal comprehensive photosynthetic benefits. The incremental dry mass and IWUE of AII70 were significantly higher than those of the other treatments. Therefore, we recommend applying a moderate water deficit through alternate infiltration irrigation (AII70) for water management in mango seedling cultivation.