Effect of growth regulators, PGPR and nitrogen on growth of apple nursery plants under protected conditions

The present investigations were conducted to assess the effect of growth regulators, plant growth promoting rhizobacteria (PGPR) and nitrogen on growth of nursery plants of apple under protected conditions at the experimental field of Department of Fruit Science, Dr Y S Parmar University of Horticulture and Forestry, Nauni, Solan. The experiment was laid out in completely randomized design consisting of 18 treatments viz. soaking of seeds in 50 and 100 ppm GA₃, PGPR's Bacillus licheniformis and Bacillus methylotroicus for 12 hours before sowing, drenching of seedlings with Bacillus licheniformis and Bacillus methylotroicus, soaking of seeds + drenching of seedlings with Bacillus licheniformis and Bacillus methylotroicus, spray of GA₃ (50, 100 and 150 ppm), CPPU (5, 10 and 15 ppm), urea (0.5, 1.0 and 1.5%) and untreated control. Each treatment was replicated thrice. The results revealed that seed soaking in 100 ppm GA₃ for 12 h resulted in significant increase in height (86.03 cm), diameter (6.11 mm) and root growth (14.50 m), proportion of buddable seedlings (97%) and saleable plants (97%) in comparison to control. Soaking of seeds and drenching of seedlings with Bacillus licheniformis also registered better seedling and root growth and 95% seedlings attained buddable size in the month of July and resulted in production of 94% saleable plants in a year.