DEVELOPMENT OF ANTHERS AND POLLEN GRAINS IN A WILD-SPECIES RELATED TOTHE SUGAR-CANE (SACCHARUM-SPONTANEUM)

A study of the histocytological characteristics of anthers and pollen development of fertile male genotypes of Saccharum spontaneum L. suppo rt the division of microsporogenesis into nine distinct stages: premei osis, meiosis and tetrad, young uninucleate microsporal stage, median uninucleate microsporal stage, median vacuolized uninucleate microspor al stage, late vacuolized uninucleate microsporal stage, first pollini c mitosis, second pollinic mitosis, mature pollen. Pollen grains are s ubspherical, monosporal, operculated with verrucose type ornamentation s. A secretory type tapetum, present from the very first microsporal s tages, is covered with orbicules persisting until anthesis.