Lu Y.-G. and RUTGER J. N. Anther and pollen characteristics of induced genetic male sterile mutants zn rice (Oryza sativa). ENVIRONMENTAL AND EXPERIMENTAL BOTANY 24, 209--218, 1984. Spikelet fertility, anther length, anther width, anther dehiscence, pollen stainability and number of pollen grains per anther were studied in 11 genetic male stcriles and their parent cultivar M-101. Four lines set some seed under bagged conditions, indicating that some self pollination occurred in these lines. Anther length was near-normal in several lines, while anther width was universally reduced. Seven lines had indehiscent anthers. Pollen stainability and number of pollen grains per anther ranged from zero to near-normal. One line showed anther and pollen characteristics similar to the fertile parent, except that the pollen of the sterile line failed to germinate. Based on the combined anther and pollen characteristics, the I 1 lines were classified into four types: stainable pollen abortion type (SPA), partial pollen abortion type (PPA), complete pollen abortion type (CPA), and no pollen type (NP). The CPA type, which is relatively easy to identify visually, and which shows appreciable outcrossing, appears to be the most useful type for male sterile facilitated population improvement schemes.