FRUIT SHAPE IN CUCUMBER AS INFLUENCED BY POSITION WITHIN THE PLANT, FRUIT LOAD AND TEMPERATURE

The shape of cucumber fruits expressed as the length/circumference rat io is an important quality factor. The fruit shape of parthenocarpic c ucumber fruits was measured during fruit development and the effects o f position within the plant, fruit load (number of fruits per plant) a nd temperature were analysed. At 25-degrees-C the length/circumference ratio increased until 4 days after anthesis and declined thereafter. The length/circumference ratio of the fruits was low at positions arou nd leaf axil 12 and was highest for fruits from the branches. The shap e of the fruits was apparently predetermined by their position within the plant. The number of fruits competing for assimilates had no effec t on the pattern of development over time of the length/circumference ratio. With decreasing number of fruits per plant the fruits reached t he marketable size (weight) at an earlier developmental stage, resulti ng in marketable fruits with a large length/circumference ratio. An in crease in temperature hastened fruit development, but when the length/ circumference ratio was plotted against the temperature sum the effect s of temperature on the length/circumference ratio were only small.