Abstract: In this study, five water treatments (T₈₅, T₇₅, T₆₅, T₅₅ and T₄₅, standing for 85%, 75%, 65%, 55% and 45% of the soil waterholding capacity, respectively) were set and a drip irrigation (10 mm each time) was triggered when the soil water level reached the designed lower limit of relative soil water content during the reproductive period of muskmelon to investigate the effects of water deficit on fruit development and quality in a plastic greenhouse. The results showed that there were three stages of fruit development, about 7-10 days (the growth rate of the fruit diameter was 3-5 mm·d^-1) after pollination was the first stage, 10-19 days (1-2 mm·d^-1) was the second stage, and 19-35 days (<1 mm·d^-1) was the third stage. Fruit growth rates in the different water treatments showed a fluctuating trend with supplemental irrigation. Under different irrigation treatments, supplemental irrigation produced different compensation effects on yield due to the water deficit stress. With the decrease of irrigation water amount, the yield was decreased by 0.60%, 3.59%, 10.18% and 16.17% compared with T₈₅. T₇₅ had no difference in weight of single fruit compared with T₈₅, but had significant differences with other treatments. The fruit diameter decreased, the fruit coat became lighter, and fruit shape index decreased with decreasing the irrigation amount. The soluble solid, limbic sugar and center sugar contents were raised firstly and then reduced, with the highest in T₇₅. Soluble sugar and protein contents were the highest in T₇₅, but no significant difference was found among the different treatments. Fruit Vc and free amino acid contents were the highest in T₆₅, being significantly different with other treatments. The contents of sugar and acid were the highest in T₇₅, being significantly different with those in T₆₅, T₅₅, and T₄₅. Overall, T₇₅ was suitable as a soil water lower limit for muskmelon at the reproductive period in plastic greenhouse in Wuhan.

Key words: ecological migrant settlement, stakeholders, risk identification, ecological risk