Effect of Nitrate-N and Ammonia-N Ratio on the Cutflower Quality of Spray Chrysanthemum
Produced in the Protected Facility
Chang, C. S., Y. T. Chang, Y. C. Wang and S.S. Wang
Effects of 4 ratio of NO3-N and NH4-N application on the cutflower’s quality was studied in three local spray-type chrysanthemum varieties grown in non-tillage, non-pinching and high-density culture with drip irrigation in the protected facility. The greenest leaves on the lower nodes of stem occurred at NO3-N and NH4-N ratio was 2:8, which mean higher NH4-N concentration in the solution, being fertilized. In the cut flower’s quality, the longest stem was found under NO3-N and NH4-N ratio was 6:4 being fertilized. The stem’s diameter was smallest, inflorescence were shortest, fresh weight of cut flower were lightest at NO3-N and NH4-N ratio was 8:2 than others. The vase life was no different through all the treatment, though. The conclusion is: to get good cut flowers quality in both leaves and flower of the 3 spraymum varieties, plants must be fertilized with equivalent ratio of NO3-N and NH4-N, or fertilized with different ratios of NO3-N and NH4-N along with the growth period of the spraymum.
Key word: Spray mum, Protected facility, Nutrition, Nitrogen, Quality
Accepted for publication: 13 May, 2003