Effect of Ethephon and Dichlorprop on the Growth and Maturation of Fruit in 'Niitaka' Pears

Ethephon 및 Dichlorprop 처리가 배 '신고'의 과실 생장과 성숙에 미치는 영향

This study was conducted to find a potential effect of ethephon or dichlorprop spray on the fruit growth and maturation in 'Niitaka' pears. Chemicals were applied between June 10 to 24 (7-9 weeks after full bloom). Ethephon in the range from 25 ppm to 100 ppm, and dichlorprop from 20 ppm to 40 ppm reduced the fruit size regardless application time and concentration. The fruit growth was more inhibited at the higher concentrations in both chemicals. Flesh firmness was more rapidly decreased in the fruit treated by both chemicals. Firmness at harvest was lowest in the treatment of 100 ppm ethephon. The climacteric increase of ethylene synthesis occurred earlier in the fruit treated by ethephon or dichlorprop regardless application concentrations and the maximum peak of ethylene production was rugher. Total phenolics significantly reduced in fruits treated with ethephon. However, the contents of soluble solids and acid were not affected by ethephon or dichlorprop treatment. Ground color was changed rapidlys by the treatments resulting in the early maturation of fruit. Optimum maturity of fruit was shortened 2-3 days by ethephon and 3-4 days by dichlorporp when maturity was determined on the basis of ground color development and firmness.

식물 생장조절제인 ethephon과 dichlorprop 처리가 배 '신고' 과실의 생장과 성숙에 대한 영향을 살피기 위하여 만개후 8주를 전후하여 시기와 농도를 달리 처리한 다음 과실의 비대 생장과 숙기에 대한 영향을 조사하였다. Ethephon은 25-100ppm, dichlorprop는 20-4ppm 농도 범위에서 처리 시기나 농도에 관계없이 모두 과실의 비대 생장을 억제시켰으며 괴질 비대 억제효과는 처리 농도가 높을수록 커지는 경향이었다. 반면에 과육의 정도는 약제 처리에 의하여 빠르게 저하된 경향이었으며 특히 ethephon 10ppm처리시 성숙기의 경도가 다른 처리에 비하여 유의하게 낮았다. 반면에 지색은 약제 처리시 빠르게 변화하였고 따라서 숙기는 ethephon 처리시 2-3일, dichlorprop 처리시 3-4일 촉진되었다. 또한 두 약제 모두 과실의 ethylene 생합성량의 증가를 촉진시켰으며 최대 생합성량도 증가된 경향이었다. 또한 수확기의 phenol 함량도 약제 처리에 의하여 감소된 경향이었다. 그러나 가용성 고형물 및 산 함량은 약제 처리의 영향을 거의 받지 않았다.