Abstract:It is plagued by poor quality and low yields that muskmelon production in the semi-arid climate in China.In addition to soil water, it is well-known that muskmelon plant roots require an adequate and continuous supply of soil air in order to respire, grow, develop, and function normally.Rhizosphere hypoxia effects influence crop yield, shoot and root growth, and quality of production negatively.Hypoxia causes stomatal closure and reduction in transpiration rate, photosynthesis and leaf chlorophyll as well as protein content.Artificial aeration has been shown to promote root metabolism and growth, also it enhanced nutrient absorption and soil redoxase enzyme activity as well as accelerated the growth and yield of vegetables.In this context, under sub-surface drip irrigation, in the wetted portion of the root zone, the possibility of hypoxia is almost certain, especially in heavy soils with slow internal drainage and during the period immediately after irrigation.It was hypothesized that varying the irrigation rate, aeration frequencies and amount along with the depth of the drip irrigation tubing would result in different yield and quality of muskmelon.To explore the influence of root zone aeration frequency, lateral depths of subsurface drip irrigation belt and irrigation amount on fruit yield, quality and irrigation water were used efficiency of muskmelon.The experiment was implemented from April to July 2014 in a 108 m long and 8 m wide greenhouse (E108°02′, N34°17′), located, at Yangling, Shaanxi Province, China.A fractional factorial experiment was designed to study the root system responding to 3 levels of sub-surface drip irrigation in combination with drip-tubing placed at each of 3 depths in the soil, and 4 levels of artificial soil aeration.Based on wetting the soil volume (Vs) in 0.60 cm of the soil profile (Vs = 5.5 m2×0.6 m), the irrigation levels were designated as 70%, 80%, and 90% of the gravimetric field capacity, and the drip irrigation placement depths were 10, 25, and 40 cm below the surface of the ridge.Artificial aeration treatments were none or aeration at daily, 2-day, and 4-day intervals.The volume of air in each plot was injected into the drip tubing via a manifold connected to the air compressor.These studies suggest that according to the influence degree on fruit shape(fruit length, diameter and flesh thickness), yield and quality(total soluble solids, soluble protein, titratable acid, soluble sugar and vitamin C content), these factors can be arranged as follow(descending): aeration frequencies, depths of subsurface drip irrigation, irrigation amount; for the use of irrigation water use efficiency of muskmelon.Aeration was suggested to be applied once a day and lateral depths of subsurface drip irrigation was 25 cm, which have positive impact on muskmelon yield, quality (total soluble solids, soluble protein, titratable acid, soluble sugar and vitamin C content), fruit shape(fruit length, diameter and flesh thickness) and irrigation water use efficiency.The content of total soluble solid can reach the maximum when water soil content attended to 80% of the field capacity; the content of total soluble sugar, yield and irrigation water use efficiency can reach the maximum when irrigation amount attended to 70% of the field capacity.Therefore, based on production, quality and water use efficiency, aerating once a day, lateral depth was 25 cm and 70% field capacity would be the most appropriate treatment combination for starting irrigation grows of muskmelon in the plastic greenhouse.For the observed responses, the information on how the muskmelon adapt to artificial soil aeration would provide guidance for field production practices as well as indications of possible mechanisms.