Occurrence of soluble carbohydrates on the phylloplane of maize (Zea mays L.): variations in relation to leaf heterogeneity and position on the plant

summary Two techniques for collection of water-soluble substances, particularly carbohydrates, from the leaf surfaces (phylloplane) of maize (Zea mays L.) were compared in order to explain the oviposition preference of the European corn borer. By dipping the leaves in water, smaller amounts of substances were obtained than by spraying water. The total amounts of three sugars (glucose, fructose and sucrose) collected from maize phylloplane ranged from 0.6 to 3.6 mg m−2 of leaf surface. The quantities of these substances varied with the variety of maize, with leaf position, and with the part of the leaf. Sugar ratios on the phylloplane were quite different from those observed within the leaf.