The Influence of Temperature, Amino Acid, and Polyamine on Pollen Germination of Pepper (Capsicum annum L.)

Evaluation of pollen viability was conducted for peppers and methods for improving pollen germination under abnormally high temperatures were studied. Optimum temperature for pollen germination was 25 °C, but percent germination decreased at 27.5 °C and 30 °C. Concentration of sucrose and pH of the medium that is proper for higher pollen percent germination and pollen tube growth was 10~15% and 5.5~6.5, respectively. Pollen percent germination was different depending on the pollen collection time during a day. Generally, pollens collected at 10 in the morning showed the highest percent germination, while decreased pollen viability was observed as collected late in the afternoon. Pollen percent germination was improved when two amino acids, asparagine and glutamine, were added in the pollen germination medium. In addition, putrescine and spermine also improved pollen percent germination. Overall, an additive and its concentration for enhanced pollen germination at high temperature in pepper was found in the treatment of 1 mM of supermine, which increased germination rate by 15.0% as compared to control.