الفهرس 
Electrophoresis and isoenzymesOnly 14 pages are availabe for public view
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Abstract
This investigation was undertaken to detect the morphological, cytological basis of affinity and the biochemical variations between the Asian and African cultivated species; Oryza sativa L. and 0. glaberrima Steud. Furthermore, to establish the extent of interspecific, intersubspecific and intervarietal sterility of F1 hybrids between the two cultivated species and among distinct ecotypes japonica with indica and a bridgegarent; indica-japonica and for understanding the morphological, cytological and biochemical basis of sterility. The materials used in the present study included nine cultivars; the sub-species indica cultivar; IR 28, the subspecies japonica cultivars; Nahda, Giza 172, Reiho, Kaohsiung 141, Calrose 76 and H 54, of the Asian rice species Oryza sativa and the African cultivar Saria 480 of 0. glaberrima as well as the indica-japonica bridgeqarent; Milyang 23 cultivar and their fifteen F1 crosses. The morphological and economical characters under study were plant height, panicle length, number of days to flowering, number of ear-bearing tillers / plant, shattering ability, flag-leaf area, number of filled grains / panicle, panicle weight and spikelets sterility. The cytological observations involved in this study were the chromosome associations, chiasmata frequency per cell and per bivalent and coefficient of terminalization at diakinesis and metaphase I stages and the meiotic chromosomal behaviour at the first and second anaphase, telophase and quartet stages.