Response of Drip Irrigation and Plastic Mulch on Quality of Sapota (Achras Zapota) Fruits

The field experiment was conducted to study the response of sapota (Achras zapota) crop under drip irrigation and plastic mulch. Different amounts of irrigation water application through drip and ring basin irrigation methods along with plastic mulch treatments were experimented with five replications. The Sapota crop water requirement was estimated using reference evapotranspiration data and crop co-efficient for different crop growth stages. Reference evapotranspiration was estimated using FAO-56 Penman Monteith approach. The irrigation water was applied at 60%, 80%, and 100% of the crop water requirement using drip and ring basin irrigation system. The quality analysis of sapota fruit was performed to investigate the effect of different treatments. Economic analysis was carried out to study the economic feasibility of using drip irrigation and plastic mulch for sapota cultivation. The water requirement of sapota crop varies between 10.71 L per day per plant in winter and 34.43 L in summer for the treatment of 100% water requirement of the sapota plant. The physical properties like fruit weight, volume, dimension, peel-pulp ratio was found to be increased due to increase in amount of irrigation water application from 60% to 100% using drip irrigation. A small decrease in true density of fruit was observed with the increase of size of fruit. The pH of fruit increased with decrease in irrigation water application through drip system. The TSS, total sugar and reducing sugar were estimated to increase with reduced irrigation water application. Sweetness of the fruit increased with reduced irrigation water application. Increase in Sapota fruit yield varied from 7.62% to 41% in mulched treatments. Increase in fruit yield by 21.05% for the drip treated plants was over ring basin. Based on the water use efficiency, benefit-cost analysis and fruit quality analysis 80% irrigation requirement supplied through drip system along with plastic mulch treatment can be recommended for Sapota irrigation.

• Application of plastic mulch alone increased the yield of crop which varies from 7.62% to 41% in different irrigation treatments.

• Yield of sapota crop was found to increase by 21.05% due to drip in comparison to ring basin irrigation.

• Income from the sapota crop due to plastic mulch was found to vary between ` 18000 (US$ 324) and ` 46000 (US$ 828) per hectare of land under different treatments under investigation.

• Water use efficiency was found maximum for the treatment T4 (0.8VDM) as 6.71 kg ha⁻¹ mm⁻¹.