Effect of Spacing and Training System on Morpho-physiology, Yield, and Quality Attributes of Litchi cv. ‘Shahi’ Under the Rectangular System of Planting

An experiment was conducted at the ICAR-National Research Centre on Litchi, Muzaffarpur (Bihar), India, during the periods 2018–2019 and 2019–2020 to assess the effect of spacing and training system on morpho-physiology, yield, and quality of litchi. The maximum plant height was found at the spacing of 8 m × 8 m (4.25 m), but the highest increase in plant height during the study period was recorded in close planting T1 (4 m × 3 m with supporting system) (30.47%). The highest increase in plant spread was recorded in T1 (13.15%), but the highest increases in canopy area were noted in treatment T2 (4 m × 3 m without supporting system) (30.86%). Light interception within the canopy was higher in wider-spaced plants. Light interception was highest under wider spacing in the upper canopy (93.31%). The photosynthetic rate (Pn) and stomatal conductance (gs) value were higher in low-density plants. The rate of transpiration was highest (2.38 mmol H2O/m2/s) at the spacing of 8 m × 8 m, and water use efficiency was found to be highest in high-density plants. A higher internal carbon dioxide concentration was found in less densely planted plants. The maximum mesophyll efficiency value was recorded in close-spaced plants. Total nitrogen, phosphorus, and potassium contents were found to be higher in wider-planted plants. The number of panicles per branch increased in wider spacing. The maximum fruit yield per plant (46.79 kg/plant), fruit weight (22.04 g), and total soluble solids (20.40 0B), as well as maximum total sugar (15.10%) and organoleptic score of fruit (8.45) were recorded under the wider spacing system of planting.