Effects of Forenoon Temperatures in Ventilated Greenhouse on the Growth of Forced- and Fall-cropped Cucumber Cultivars

Abstract

Varietal difference on forced- and fall-cropped greenhouse-grown cucumbers by reducing assimilation competition between lateral branches and fruits was investigated. The treatments consisted of exposing cucumber plants to different amounts of ventilation in greenhouses to keep them at 29°C and 70% relative humidity (RH) or 25°C and 55% RH. For all cultivars, the number of days from the first female flower bloom to harvest in the 29°C/70% plot was less than that in the 25°C/55% plot. ‘Pandex’ matured in the least number of days from the opening of the first female flower to harvest in the 25°C/55% plot. These results indicated that the fruit growth was regulated by the fruit growth ability calculated as the number of days of female flower blooming until harvest of each cultivar rather than the number of lateral branches.