1996 Volume 65 Issue 2 Pages 355-361
The effect of phosphorus application rates on growth and cut flower quality of chrysanthemum cv. Shuhounochikara plants grown using a nitrogen application curve in NFT system was investigated.
The phosphorus treatments consisted of four P : N ratios ; P being 6, 12, 18, and 24%of the amount of initial nitrogen applied. In the fifth treatment plot, 24 ppm phosphorus were applied, which was equivalent to 12% of the nitrogen supply. In this treatment, however, nitrogen was not supplied along a nitrogen application curve, but was applied and adjusted on a weekly basis to 200 ppm.
Plants of P 6%plot had shorter flower stems and had incipient symptoms of phosporus deficiency. In the P 12% plot, plants grew and flowered normally, and produced high quality cut flowers. However, plants of both the P 18% and P 24% plots exhibited symptoms of excess phosphorus and had short flower stems. Plants of the P24 ppm plot flowered normally, but had excessively large leaves and stems for marketable cut flower.
Based on these results, the optimum applied phosphorus to nitrogen ratio, along nitrogen application curve in NFT system was 12 : 100.