Abstract: Techniques for collecting and measuring floral nectar are essential in many studies of pollination biology. In order to test the effectiveness of different methods for collecting nectar from small flowers, we used microcapillary tubes, calibrated syringes, wicks and centrifugation to collect floral nectar in five species (Sagittaria trifolia L., Elsholtzia ciliata (Thunb.) Hyland, Dolichos lablab L., Rostellularia procumbens (L.) Nees, and Polygonum caespitosum L.). We also used hand-held refractometer to analyze the nectar sugar content. The results have shown that the applicability of one method varied with the floral shape and structure, nectar volume and the nectar location. It is better to use different methods to measure different flowers. For studies in the field, the techniques of using capillary tubes to collect nectar and hand-held refractometer to measure sugar content are recommended. If the flowers are too small to collect with capillary tubes, we suggest centrifugation as an alternative method to extract nectar in the laboratory.

Key words: Floral nectar, nectar collection, sugar analysis, microcapillary tube, hand-held refractometer, pollination biology