Effect of various levels of nitrogen on quantitative and qualitative parameters of Rose var. “Top Secret” under poly house condition

Abstract

Study was conducted to find out the effect of various levels (100, 150, 200, 250,300 mg/plant/week) of nitrogen on growth parameters in terms of qualitative and quantitative traits of rose var. Top Secret. Plant growth in general increased with increase in nitrogen levels. Among various levels of nitrogen application, 300 mg nitrogen per plant per week significantly increased all vegetative growth parameters and showed maximum plant height (117.45 cm), leaf area (98.91 cm2 ) and a number of leaves (62.50). Further, flowering parameters like stalk length (83.53cm), bud diameter (2.45cm), bud length (2.55 cm), number of flowers per plant (7.30) as well as per square meter (53.05) were also significantly maximum in plants given nitrogen @ 300 mg per plant per week. Leaf N (2.94 %), P (0.19%), K (1.87%) and chlorophyll content in leaves (4.41mg/g) was also higher with 300 mg N per plant per week. Vase life (10 days) and anthocyanin content in petal tissue (2.09 mg/g) were found the maximum in plants given nitrogen @ 250 mg per plant per week, which was at par with the treatment of nitrogen @ 300 mg per plant per week. Nitrogen should be applied at the rate of 300 mg/plant/week under protected cultivation as the optimum dose for good plant growth and qualitative flower production in rose var. Top Secret under protected cultivation.