Influence of Zinc Nano-Particles and Bulb Size on the Growth and Flower Production of Tuberose

A Research was conducted on “Influence of Zinc nano-particles and bulb size on the growth and flower production of tuberose” at the Ornamental Horticulture Nursery, Department of Horticulture, The University of Agriculture Peshawar, during the year 2023. The Experiment was conducted in Randomized Complete Block Design (RCBD). The treatments were repeated three times in field. Factor A included the bulb sizes, which was 20 mm, 30 mm and 40 mm in diameter and Factor B had different concentrations of zinc nano-particles Zn (NPs), which were 0, 150 mgl-1 zinc sulphate, 50 mgl-1 Zn (NPs), 100 mgl-1 Zn (NPs), and 150 mgl-1 Zn (NPs). As per experimental findings, bulb sizes and Zn (NPs) concentration had significantly affected most of the attributes. Interaction between bulb size and Zn (NPs) was found significant for two parameters such as fresh florets weight and dry florets weight. The results of bulb sizes revealed that highest number of leaves plant-1 (24.02), plant height (107.73 cm), leaf area (577 cm2), chlorophyll content (64 SPAD), number of florets (35.1), highest florets fresh and dry weight (8.3 and 4.1g), vase life (8.8 days), bulb weight (39 g) and bulb size (36 mm) in tuberose plants having bulb size 40 mm. While maximum days to spike emergence (83.7), days to first florets opening (98.03) and days to last floret opening (101.47) with minimum number of leaves (18.8), plant height (97.20 cm), leaf area (467 cm2), chlorophyll content (54 SPAD), number of florets (23.5), lowest florets fresh and dry weight (4.9 and 2.4 g), vase life (8.1 days), bulb weight (34 g) and bulb size (30 mm) were noted in tuberose plants having bulb size 20 mm. In case of Zn (NPs) concentration, the maximum number of leaves (26.4), plant height (114.89 cm), leaf area (554 cm2), chlorophyll content (66.3 SPAD), number of florets (37.0), highest florets fresh and dry weight (8.6 and 4.4 g), vase life (11.5 days), bulb weight (51 g) and bulb size (42 mm) was recorded in tuberose plants treated with 150 mgl-1 of Zn NPs. On the other hand, minimum leaves (13.7), plant height (83.33 cm), leaf area (488 cm2), chlorophyll content (57.6 SPAD), least number of florets (23.3), lowest florets fresh and dry weight (4.7 and 2.4 g), vase life (6.4 days), bulb weight (25 g) and bulb size (24 mm) were observed in plants treated with distilled water (control) plants. It is concluded that foliar application of Zn (NPs) at 150 mgl-1 proved optimum concentration for better growth and flower production with higher quality florets in tuberose. Among various bulb sizes, the plants of tuberose raised from 40 mm bulbs were superior for all the studied attributes as comparted to plants grown from 20 and 30 mm bulbs.