Scheduling of drip irrigation under the ultra-high density of guava orchard

Over two consecutive years (2012–2013 and 2013–2014), a field experiment was conducted on a 5-year-old guava orchard of cv. Sardar in Ranchi, where drip irrigation systems were installed in ultra-high-density guava orchards. The experiment aimed to study the water system booking and water prerequisites of guava based on available soil water content and its consumption, as well as the pan evaporation replenishment. 240 guava trees were organized in a randomized block design consisting of four repetitive blocks, with a spacing of 1.0 m x 2.0 m. Five irrigation scheduling methods were applied in the field experiment, which included four levels of open pan evaporation primarily-based drip irrigation schedules (20%, 40%, 60%, and 80% pan evaporation replenishment) and one rainfed plot as a control. Each treatment contained 12 plants per unit with four repetitions for each treatment. The results indicated that irrigation scheduling based on pan evaporation replenishment had better yield and quality compared to the schedule method for water system plans. Tree grown under irrigation level at 20% of PE showed maximum irrigation water use efficiency (IWUE), which decreased with the increasing quantity of water applied. Application of irrigation at 60% PE showed higher fruit yields of guava planted at ultra-high density, with some parameters like an increase in fruit weight being observed to be better under this treatment. Moreover, reducing the quantity of water applied from 100% PE to 60% PE did not affect the fruit quality parameters. Therefore, it is suggested to utilize water at 60% of PE letter with two days irrigation interval for commercial cultivation of guava under ultra-high-density planting patterns.