Calcium Deficiency Symptoms in Greenhouse Cucumbers

In a sand culture experiment with seeded and seedless greenhouse cucumbers (Cucumis sativus L.), induced Ca deficiency over a range of nutrient Ca applications produced characteristic foliar and plant symptoms. Severe deficiency was associated with top leaf tissue levels of 0.20% Ca and less. Fruit symptoms were a proportionate stunting, center and stem-end constriction in Burpee hybrid, and a progressively darker green color in Sporu. Mild symptoms were difficult to recognize and could only be confirmed by tissue analysis, although it was not possible to determine an exact threshold value for incipient deficiency.