Characterization of the isolated and purified pollen at respective stage. (A-H) DAPI staining of the purified pollen: (A, B) Uninucleate microspores (UNMs). (C, D) Bicellular pollen (BCP). (E, F) Tricellular pollen (TCP). (G, H) Mature pollen grains (MPGs). (I) Germinated pollen grains (GPGs). (J) The purity of the purified pollen was determined by DAPI staining and microscopy, and percentage of GPGs. Bars = 100 μm in A to I.