熱融着性ポリエステル繊維固化ポットレス培地で育成したペチュニアの生育に及ぼす灌水方法の影響

Recenty, polyethylene pots(PP) present a significant environmental issue for waste disposal. To develop bedding plant production system without PP, properties of compacted medium hardened by heat fusion polyester fiber were investigated. Effects of irrigation methods on the growth of vegetative propagated petunia grown in medium without PP were investigated. The effect of medium type was not as significant as the difference in water loss per pot. Water loss per pot of medium without PP was about two times greater than medium held in PP. No compacted medium disintegrated easily without root-ball formation, and in 20 days after cutting about half of non-compacted medium had disintegrated. Compacted medium did not disintegrate before rooting. Medium type did not significantly affect rooting rates, plant heights, leaf numbers and fresh weights when transplanted to medium. Also, cell or pot medium type did not significantly affect plant heights, flower numbers, leaf numbers and fresh weights. Non-compacted medium without PP easily disintegrated with overhead irrigation. Subirrigation and much overhead irrigation had similar effect on growth when planted in containers.However, less overhead irrigation had significantly lower growth. Moreover, in less overhead irrigation, non-compacted medium without PP had remarkably lower growth than compacted medium without PP. In, conclusions, compacted medium without PP did not affect the growth of bedding plants whenever water and nutrient regime was well regulated. Compacted pot medium was easy to transplant since it did not disintegrate. Therefore, it was considered practical and feasible to use compacted medium without PP for bedding plant production.