Response of Dhalia pinnata to different levels of nitrogen alone and in combination with constant doses of phosphorus and potassium.

摘要

The effects of different nitrogen levels (0, 15, 20, 25 and 30 g/sq. ft.) alone and in combination with constant rates of phosphorus (15 kg/sq. ft.) and potassium (15 kg/sq. ft.) on the growth of D. pinnata were studied in Peshawar, Pakistan, during 1997-98. There were 20 treatments with three replications. The fertilizer treatments significantly affected the days to flowering, number of flowers per plant, plant height, number of leaves per plant, primary root length, leaf area, and root stem ratio. The maximum days to flowering (123) was recorded with 30 g N, while the minimum days to flowering (91) was noted with 15 g P. The highest number of flowers per plant (13), plant height (106.3 cm), and primary root length (17 cm) were observed in plants supplied with 25 g N+15 g P+15 g K/sq. ft. The highest number of leaves per plant (71), leaf area (27 cm2) and root and stem ratio (0.75) were recorded in plants receiving 25 g N/sq. ft. only. For D. pinnata growers, 25 g N+15 g P+15 g K/sq. ft. is recommended under the agro-climatic condition of Peshawar.