Comparison of different rock phosphate based nutrient sources on chrysanthemum (Dendranthema grandiflorum. L) in low pH soils

Abstract

Phosphorus (P) management is very important for flower crops. A field experiment was conducted in an acid soil to evaluate the effect of different phosphorus sources on soil properties, growth and yield of Chrysanthemum (Dendranthema grandiflorum L.). Three different sources at two levels (RDP at 100 and 50%) with ten treatments in three replications were arranged in simple RCBD. Phosphorus was applied through fertilizer (T3 to T6); phosphorus-enriched compost (PEC- T7 and T8); and P-rich organic manure (PROM- T9 and T10) and they were compared with absolute control and FYM alone. Recommended doses of nitrogen and potassium were applied to T3 to T10; and recommended dose of FYM was applied to T5 to T10 treatments. The results revealed that use of organic-P sources significantly improved growth and yield attributes. Among the treatments, the treatment PROM-100 recorded the highest plant height (49.88 cm), number of primary branches (19.91), plant spread area (1244.06 cm2), flower diameter (4.59 cm), number of flowers per plant (223.33) and flower yield per plant (446.67 g), outperforming both chemical fertilizers and P-enriched compost. The enhanced performance of PROM is attributed to its sustained P release, improved nutrient uptake and positive interaction with organic matter in acidic soil. Notably, supplementation half of the recommended-P through PEC-50 or PROM-50 recorded on par yields with T5 (POP). Similarly, growth and yield parameters were also found on par with each other. Thus, the study indicated that the chrysanthemum flower yields can be enhanced with the application of PROM and PEC. Moreover, the present yield levels can also be achieved even at 50 per cent of RDP through PROM or PEC application.