Influence of storage durations on seed germination and the accumulation of chromosomal aberrations in two rice varieties (Oryza sativa L.)
Keywords:Oryza sativa, chromosomal aberrations, germination percentage, mitotic index, seed storage
Influence of different seed storage duration on germinability and the accumulation of chromosomal aberrations was investigated in two rice varieties, 7079-Lang Son and 4134-Hoa Binh (Oryza sativa L.), long-term preserved in National seed bank. Our results showed that the germination percentages as well as mitotic index of the seeds of 7079-Lang Son stored for 9 years and of the 4134-Hoa Binh stored for 13 years have decreased slightly compared with unstored seeds. However, the seeds are stored for longer showed a significant (p<0.05) decrease in germination percentage and mitotic index, and increase in cells with chromosomal aberrations. Specially, the germination percentage dropped below 50%, mitotic index fell 27% and the frequency of abnormal cells increased very highly in 7079-Lang Son seeds stored longer than 3 years (seeds stored 12 year) as compared with near 100% (99.33%) germination as recorded for unstored seeds, suggest that the preserved seed viability may disappear completely. The relevance to these findings for the long-term conservation of rice germplasm is discussed.