Germination and Pollen Tube Growth of Pollen Following Self and Cross Pollination Between Cultivated Rice (Oryza sativa) and Wild Rice (O. minuta)

Abstract

By using light and scanning electron microscope it was found that morphology of Oryza sativa and O. minuta pollen were spherical shape, scabrate exine sculpturing, monoporate with operculum, annulus and monad occurrence. Pollen size of O. sativa was bigger than O. minuta. Pollen germination and stainability of the two species were rather high. Self and cross pollination of O. sativa (KDML 105, NMS 4 and IR58) and O. minuta were carried out by the use of microscope with a fluorescence filter attachment. Five hours after self pollination, fertilization of O. sativa and O. minuta were ranged from 87.5-100% with rapid growth of pollen tube. When O.minuta was pollinator, pollen germination and tube growth were normal and fertilization was ranged from 52.4-74.2% at 48 hours after pollination. In contrast, when employing O. sativa as pollinators, pollen germination and tube growth were slow and fertilization was not visible at 72 hours after pollination. The time period from pollination to fertilization for cross pollination was about 9-10 times that following self pollination of O. sativa as well as O. minuta.