Response of pomegranate (Punica granatum) to drip irrigation system in light textured soils of semi-arid regions

摘要

The study was designed to evaluate numbers and different arrangements of emitters under surface drip irrigation system in pomegranate (Punica granatum L.) cv. Bhagwa orchard grown on light textured soil. A field experiment was conducted at National Research Centre on Pomegranate, Solapur for three consecutive years (2010 to 2013). The treatments consisted of irrigation with 2 online emitters (8 lph) on single lateral (T-1), 3 online emitters (4 lph) on single lateral (T-2), 4 emitters (4 lph), 2 online, 2 through microtube on single lateral placed on four sides of plant (T-3), 6 emitters (2 lph) on double laterals placed 50 cm apart on both side of plants (T-4) and inline lateral having 8 emitters (2 lph) placed in the form of ring encircling the plant (T-5). Experiment was laid out in randomized block design with four replications. Equal quantity of irrigation equivalent to 0.80 E. Pan was applied on every alternate day. The results revealed that irrigation with 6 emitters (2 lph) on double laterals placed 50 cm apart on both sides of plants provide higher and uniform distribution of water in the root zone of the plants, resulted in better nutrient uptake, growth and yield performance of pomegranate plants. Highest leaf content of N (2.36%) and P (0.17%) was observed in this treatment which reflected in highest increase in plant height (20.4%) and plant spread (22.7%) producing highest yield in terms of numbers (36.1) and weight (6.889 kg) of fruits/plant. Plants irrigated with inline lateral having 8 emitters (2 lph) placed in the form of ring encircling the plant recorded highest leaf chlorophyll content (57.2) and maintained cool plant canopy as indicated by lowest leaf temperature during all the fruiting months. Flowering intensity was high in the plants irrigated with 2 dripper (8 lph) on one lateral system but it does not reflected in producing fruit yield due to limited wetting zone inducing moisture stress to the plants as indicated by highest fruit cracking (11.1%) in this system. It can be concluded that irrigation with 6 emitters (2 lph) fixed on two laterals placed on both sides of plants 50 cm away from the trunk along the rows system should be provided to pomegranate grown on light textured soils of semi-arid regions.