Effects of Synthetic Cytokinin, Thidiazuron, on Berry Size and Quality of 'Kyoho'(Vitis labruscana) Grapes

시토키닌 활성물질 Thidiazuron 처리가 포도 '거봉'(Vitis labruscana)의 과립비대(果粒肥大) 및 품질(品質)에 미치는 영향(影響)

This experiment was conducted to find the effect of a non-purine cytokinin, thidiazuron(TDZ), on the increase of berry size and fruit quality in 'Kyoho' grapes. For the comparison, the effect of forchlorfenuron(CPPU) was also examined The number of shot berries per cluster was significantly increased by the application of TDZ at 5 days after calyptra fall, resulting in the increase of cluster weight but no increase of each berry weight. The increase of berry weight was found when TDZ was applied at 10 to 15 days after calyptra fall. Gibberellin(GA $25mg{\cdot}L^{-1}$) was also effective on the increase of berry weight and the combined application of GA and TDZ further increased the berry weight. TDZ showed stronger effect on the increase of berry weight than CPPU at the same concentration. Berry ripening was more delayed at higher concentration of TDZ but no chemical injury was observed even at $20mg{\cdot}L^{-1}$. Results indicated that TDZ was effective on the quality improvement through berry weight increase and the recommended concentration TDZ for 'Kyoho' grapes was 5 to $10mg{\cdot}L^{-1}$.

본 실험은 새로운 비 purine계 사이토카이닌 활성 물질인 thidiazuron(TDZ)이 포도 '거봉'의 과립중 및 과실 품질에 미치는 영향을 조사하기 위하여 실시하였으며 대조 약제로 forchlorfenuron(CPPU)을 이용하였다. 생리적 낙화 후 5일의 TDZ를 처리는 과방의 무핵과립의 착립수를 증가시켜 과방중은 유의하게 증가하였으나 과립중은 증가하지 않았다. 그러나 낙화 후 10 또는 15일 처리는 무핵 과립의 착립수를 감소시켜 과립중이 유의하게 증가하였다. 따라서 TDZ처리는 생리적 낙과가 어느 정도 진행된 만개 10~15일 후에 처리하는 것이 유리하였다. GA $25mg{\cdot}L^{-1}$처리도 과립중 증가에 효과적이었으나 TDZ와 GA혼용 처리는 각 약제를 단용 처리할 때보다 과립중 증대 효과가 더욱 컸다. 두 약제간에는 TDZ가 대조약제인 CPPU가보다 과립비대 증진 효과가 더욱 컸으며 TDZ 처리 농도가 $20mg{\cdot}L^{-1}$에서도 약해는 발생하지 않았으나 착색과 성숙은 더욱 지연되는 것으로 나타나 적정 처리농도$5{\sim}10mg{\cdot}L^{-1}$이었다.