Abstract
Pollen grains from the single cross hybrid Wf9 × H55 were cultured on an artificial medium containing 15% sucrose and 0.6% bacto-agar supplemented with all possible combinations of three concentrations (0.00, 0.03, and 0.06%) of calcium nitrate and three concentrations (0.00, 0.01, and 0.02%) of boric acid. The combination containing 0.03% calcium nitrate and 0.01% boric acid produced the highest germination (47.9%) and the longest tube length (405 μ). The addition of either calcium nitrate or boric acid alone decreased the germination percentage and pollen tube length. The percentage of grains producing more than one pollen tube was reduced by the addition of calcium nitrate or boric acid singly or in combination. The significance of these results in relation to pollen physiology was discussed.