Characteristics of Pollen Germination and Pollen Tube Growth of Prunus mume in Vitro

The study examined pollen germinations and pollen tube growth of Prunus mume Sieb.Let Zucc.cultured with different medium components at different pollen densities and different temperatures and different times.It was shown that in Xiyeqing,the optimal medium of pollen germination and pollen tube growth was 30 mmol/L MES buffer(pH 6.5) containing 20% sucrose,0.01% H_3BO_3,20% PEG-4000,(0.03)% Ca(NO_3)_2 ·4H_2O and 0.02% MgSO_4·7H_2O;on the medium,the germination rate reached(45.03)% and the pollen tube length reached 597.2 μm;and the optimal pollen density of pollen germination and pollen tube growth was 20～80 pollens/mL.In Prunus mume too high and too low a culture temperature were not favorable for pollen germination and pollen tube growth and optimal pollen germination and optimal pollen tube growth appeared at 25℃.The average pollen germinations of the tree varieties,Xiyeqing,Gessekai and Oushuku was 48.6% and their average pollen tube length was 762.3 μm.Cultured at different temperatures Prunus mume pollens germinated differently,and cultured at 25℃ the pollen tubes grew most quickly,mainly within 0 ～12 hours,and the average pollen tube growth rate of the tree varieties was 58.5 μm/h.