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These studies were carried out to investigate the effects of fruiting node and growth temperature on endogenous hormone in the late parthenocarpy type cucumber ovaries(hybrid ´Khira´ , a non-parthenocarpic cultivar, X ´Pandex´, a strongly parthenocarpic cultivar). The rate of parthenocarpic fruit set in each growth stage was increased with rise of nodal positions. The contents of IAA in the ovaries also increased according to the advancing stage of plant development. The ovaries set at Stage IV (above 17th node) contained 5 times more endogenous IAA than those of Stage I (up to 6th node). The contents of endogenous ABA, gibberellin-like substance, trans-zeatin riboside (t-ZR) and dihydrozeatin riboside (DHZR), however, did not change significantly by nodal positions. The low temperature increased the rate of parthenocarpic fruit set, i.e., the average rate of parthenocarpic fruit set in all nodal position was 78% at 15℃ compared with below 30% at 20, 25 and 30℃. The content of IAA at 15℃ was 2 times higher than that at 25℃, but there was no significant difference in the content of gibberellin-like substance by growth temperature or fruiting node.
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