Oxygation Improves Yield and Quality and Minimizes Internal Fruit Crack of Cucurbits on a Heavy Clay Soil in the Semi-arid Tropics

Abstract

Lack of oxygen due to sustained wetting fronts associated with drip and subsurface drip irrigated crops in heavy clay soil can negatively impacts on yield, fruit quality and water use efficiency of cucurbit crops. This study evaluated the effects of aerated irrigation water (oxygation) with subsurface drip irrigation, employing an in-line air injector (Mazzei venturi to introduce 12% air by volume of water) on fruit yield, quality and water use efficiency of watermelon (Citrullus vulgaris) and pumpkin (Cucurbita maxima) in a heavy clay soil. The fruit yield with oxygation increased from 14.5 t ha -1 to 24.6 t ha -1 , and 26.3 t ha -1 to 28.9 t ha -1 , for watermelon and pumpkin, respectively. The total soluble solids (TSS) increased by 19% with oxygation (13.2 vs. 11.1%), and internal fruit crack decreased for watermelon, whereas in pumpkin fruit dry matter increased by 4% (40 vs. 38.4%) and TSS by 7% (13.7 vs. 12.8%). Season long water use efficiency was greater with oxygation compared to the control in both crops. The higher yield with oxygation was associated with a more rapid canopy cover, more leaf chlorophyll, and an increase in leaf photosynthetic rate, and leaf transpiration and an increase in fruit number and size. The results suggested that oxygation can ameliorate temporal hypoxia-associated with drip irrigated cucurbit crops in heavy clay soil and also offer yield and fruit quality benefits.

Yields and Nutritional of Greenhouse Tomato in Response to Different Soil Aeration Volume at two depths of Subsurface drip irrigation

“…Our previous studies had shown that soil aeration at different growth stages lead to higher quality of potted tomatos30. Consistent with Bhattarai et al 53,. significantly greater total soluble solid cucurbits were reported in the aeration treatments.…”

“…In addition to the effects on fruit appearance, aeration is known to influence the quality and taste2653. Our previous studies had shown that soil aeration at different growth stages lead to higher quality of potted tomatos30.…”

Effects of Artificial Soil Aeration Volume and Frequency on Soil Enzyme Activity and Microbial Abundance when Cultivating Greenhouse Tomato

“…Artificial soil aeration can enhance air permeability and improve soil oxygen content, effectively relieving hypoxic stress on roots (Bhattarai et al, 2006(Bhattarai et al, , 2008(Bhattarai et al, , 2010Chen et al, 2011;Pendergast et al, 2013) while maintaining soil microorganism and enzyme activities (Niu et al, 2012b). Thus, soil moisture and soil aeration are coupled, and the soil water content influences soil aeration (Boone et al, 1986).…”

Growth Response of Greenhouse-Produced Muskmelon and Tomato to Sub-Surface Drip Irrigation and Soil Aeration Management Factors

“…Supplemental soil aeration is also possible either along with the water (termed as aerated irrigation) or separately, and can effectively improve the oxygen level in rhizosphere. Studies have shown that these practices can be very useful in overcoming problems associated with hypoxia in the root zone of irrigated crops over a range of crops, soil water contents and soil types, and for improving crop performance under oxygen-deficient conditions [6][7][8].…”