Assessment of different irrigation levels on quality production of headed back guava cv. Lalit under high density plantation

Abstract

In guava (Psidium guajava L.) low production of crop due to crowding and encroachment of tree branches leading to inefficient light penetration is a general problem in older orchards. The internal bearing capacity of trees also declines with time due to overshadowing. To overcome this problem heading back of unproductive trees to the extent of 1.5 meter height above the ground level to facilitate the sprouting of new shoots below the cut point and allowing the development of productive canopy is important. In this context a field experiment was conducted during 2014- 2018 with the objective of improving yield and quality of headed back (1.5 m height) guava cv. Lalit (fifteen year old) under high density planting (6.0 x 3.0 m), accommodating 555 plants per hectare. The experimental plot was irrigated with a drip irrigation system having four irrigation levels with one ring basin irrigation method (control). The black polyethylene mulching (100 µ thickness) was used to cover 40 per cent area of tree canopy. Fertigation with recommended dose of fertilizer was applied at different growth stages. Maximum water saving (47.52%) was recorded at 80 per cent pan evaporation through drip irrigation and polyethylene mulching as compared to control. Enhancement in flowering in tune of 60 to 85 per cent and maximum fruit yield (24.0 kg tree-1) at 80 per cent irrigation level with polyethylene mulching and minimum yield (15.1 kg tree-1) in control was recorded. Drip irrigation coupled with polyethylene mulching resulted in better quality of fruits in terms of increased TSS (13.4 °Brix), total sugar (6.65%) and ascorbic acid (181.3 mg 100 g-1) without any significant change in acidity (0.24%) as compared to minimum TSS (11.0 °Brix), total sugar (6.50%) and ascorbic acid (160.6 mg 100 g-1) in control.