Establishment of in vitro pollen germination system in C4 model plant Foxtail Millet

The development and germination of pollen play crucial roles in the sexual reproduction of plants, and this process holds great potential for improving grain yield in crops. In this study, we established a germination system for foxtail millet pollen and identified culture temperature and time as key factors for successful germination. Specifically, we found that a temperature of 22 °C and a duration of 30 min provided the optimal conditions for pollen germination. It is worth noting that if the culture temperature was too high, the top of the pollen tube would expand. Additionally, we discovered that sucrose and boric acid were essential for in vitro germination of foxtail millet pollen, with 15% sucrose and 0.01% boric acid being the suitable concentrations. Moreover, we observed that the time required for pollen germination in foxtail millet was significantly shorter compared to other cereals, opening up new avenues for studying the stress resistance of foxtail millet from a reproductive development perspective. This germination system holds promise for guiding the application of male sterility or cross breeding techniques. Key Message The establishment of in vitro pollen germination and discovery of key influencing factors in C4 gramineae Foxtail Millet.