Characteristics of pollen germination and pollen tube growth in Salix viminalis in vitro

In this study, effects of temperature, light intensity and culture medium on the pollen germination were investigated through in vitro culture in Salix viminalis. The results showed that the pollen germination and pollen tube growth of S. viminalis could be affected by culture temperature and light intensity. The optimum temperature range for pollen germination was 15-25 ℃, and the highest germination rates were obtained under the light intensity of 1 500 and 2 000 lx. The concentration of sucrose, H₃BO₃ and the pH value of culture medium could remarkably promote pollen germination at a certain range based on orthogonal design. The optimal culture condition was: basal medium supplemented with 100 g/L sucrose and 200 mg/L H₃BO₃ with a pH value of 5.0. The rate of pollen germination reached 48.8% under the conditions of 1 000 lx and 25 ℃. There were no significant differences in the pollen germination between in vitro which used basal medium supplemented with 100 g/L sucrose and 200 mg/L H₃BO₃ with a pH value of 5.0 and pollen germination on stigma.