6-benzylaminopurine, Spermidine 및 빛 처리에 따른 ‘샤인머스캣’ 포도의 액아 발달

Abstract

‘샤인머스캣’ 포도는 신초에서 꽃송이가 나오지 않는 빈가지 발생이 빈번하여 생산량이 감소되는 문제점을 가지고 있다. 따라서 본 연구에서는 ‘샤인머스캣’ 포도의 빈가지 발생을 경감시키고자 환경휴면기와 생육기에 식물생장조절제인6-benzylaminopurine(BAP)과 spermidine(SPD) 및 환경요인인 빛 처리를 통해 액아의 발달을 연구하였다. 환경휴면기의 생장조절제 및 빛 처리는 액아의 크기에는 영향을 미치지 않았으며, 화원기 형성률과 꽃송이 출현률은 BAP 처리에서 가장 높았다. BAP 농도에 따른 화원기 형성률은 내재휴면이 끝난 후 BAP 200ppm을 처리하는 것이 화원기 형성에 가장 유리하였다. 생육기의 생장조절제 처리시, SPD 처리에서 가지의 길이와 액아의 생장이 촉진되는 반면 화원기형성률은 낮았으며, BAP 처리는 반대로 액아의 생장이 억제되는 반면 화원기형성률이 높게 나타났다. 장일처리시 기내 실험과 마찬가지로 화원기 형성이지연되었다. 모든 처리에서 눈 괴사율은 매우 낮은 수준으로 처리간 통계적 유의성이 인정되지 않았다. ‘샤인머스캣’ 재배시주로 이용하는 단초전정시 1, 2번 액아의 화원기형성률이 현저하게 낮았으며, BAP 처리가 1, 2번 액아의 화원기 형성을 촉진하나 이듬해 꽃송이출현률은 무처리구와 비슷한 것을 확인하였다. 따라서 ‘샤인머스캣’ 포도의 빈가지 경감을 위해서는 내재휴면이 타파된 후 환경휴면기에 BAP 200ppm을 처리하는 것이 가장 적합하다고 판단된다.

‘Shine Muscat’ grape production is challenged by the frequent occurrence of empty branches that do not exhibit flowers on the shoot. Therefore, in this study, axillary bud development was investigated by treating with plant growth regulators [6-benzylaminopurine (BAP) and spermidine (SPD)] and an environmental factor (long-day treatment) during ecodormancy and the growth stage to reduce the occurrence of empty branches in ‘Shine Muscat’ grapevine. Treatments with growth regulators and light during ecodormancy did not affect bud size, but flower primordium formation and flower cluster appearance rates were the highest after BAP treatment. Flower primordium formation rate was the most efficient when 200 ppm BAP was applied after endodormancy break. When plants were treated with growth regulators in the growth stage, SPD treatment promoted the growth of shoots and buds but reduced the flower primordium formation rate. In contrast, BAP treatment inhibited bud growth but increased the flower primordium formation rate. In the case of long-day treatment, the formation of the flower primordium was also delayed as in an in vitro experiment. The whole bud necrosis rate was markedly low, and no significant difference was observed after all treatments. The flower primordium formation rates of the first and second buds that are mainly used for the cultivation of ‘Shine Muscat’ were remarkably low. Although BAP treatment promoted the flower primordium formation rate of the first and second buds, it was confirmed that the rate of cluster appearance in the following year was similar to the untreated group. Therefore, we suggest that 200 ppm BAP treatment during ecodormancy is the most efficient approach to reducing the occurrence of empty branches in ‘Shine Muscat’ grapevine.