Use of somaclonal variation and in vitro selection for chilling tolerance improvement in rice

摘要: Embryo-derived calli of four rice varieties cultivated at high altitude in Burundi - Facagro 57, 76, Kirundo 3 and 9 were submitted to different temperature regimes. The percentage regenerating greatly varied depending on variety, length culture callus treatment. reduction regeneration percentages induced by low was more pronounced the sensitive varieties. Regenerated plants (RO) their progenies R1, R2 R3 cold-screened together with control plants. In all varieties, significantly higher survival rates obtained vitro than Such chilling tolerance improvement not following a massal selection applied during successive generations onto regenerated from either 25 degrees C, 4 altitudes two generations. For most observed traits, characterized lower means, larger variation maximum values chilling-tolerant somaclonal families usually extensive differences fatty acid composition, chilling-induced electrolyte leakage chlorophyll fluorescence, compared they derived from.