キュウリ果実の着果•肥大期における光合成産物の転流•分配に及ぼすベンジル•アデニンの影響

Abstract

Studies were carried out to clarify the effects of benzyl adenine on translocation and distribution of 14C-assimilates in relation to fruit setting and development in cucumber plants.Fruit setting and early fruit development were accelerated by pollination. Furthermore, parthenocarpic fruit setting was induced by benzyl adenine. Great changes occurred on the RSS (Relative Strength as a Sink) values before and after anthesis.The RSS value was high before anthesis and it decreased rapidly on the day of anthesis. After pollination or treatment by benzyl adenine the RSS increased rapidly again.The changes in auxin content by pollination and treatment by benzyl adenine were almostly similar in pattern to the changes of the RSS. Therefore, it seems that the effect of benzyl adenine is related to the inhibition of decrease of auxin content.14C-benzyl adenine moved to the acropetal area of fruit and accounted for more than 10 per cent of total amount of 14C supplied to fruit within 24h.There were physiological changes in the flower buds before and after anthesis. It is likely that the flower bud acts as a growing point, like a leafy bud, before anthesis. However, from the time of anthesis until fruit setting the flower bud suspends physiological activity and after fruit setting the flower bud probably changes physiological phase and the fruit develops rapidly.