Effects of root pruning on seedling growth and other parameters in Juniperus polycarpos under nursery condition

A nursery trial was conducted to study the effects of root pruning on the seedling growth and other parameters of Juniperus polycarpos. Roots of two-year-old seedlings of J. polycarpos were pruned at different levels and transplanted in polybags of size 9’’ × 5” filled with potting media comprising soil, sand, and farm yard manure (2:1:1). Maximum growth of various seedling parameters, viz., shoot length (42.90 cm), root length (38.40 cm), collar diameter (6.16 mm), number of roots (45.93) and biomass, viz., fresh shoot biomass (24.03 g), fresh root biomass (6.35 g), total fresh biomass (30.38 g), dry shoot biomass (10.21 g), dry root biomass (2.48 g), total dry biomass (12.69 g), weight of secondary + tertiary roots (0.61 g) were recorded in seedlings in which 5 cm roots were retained after pruning, whereas, minimum growth of seedling parameters and biomass was recorded in seedlings in which no root pruning was done. The maximum value of seedling quality parameters, viz., volume index (1627.86), Quality index (1.14), and ratio of secondary + tertiary roots to total root biomass (0.08) was also observed in seedlings in which 5 cm roots were retained after pruning. The study suggests that roots of J. polycarpos may be pruned up to 5 cm in length for production of quality nursery stock.