RAPD分析

Maintaining lhe purity of rice varieties is the primary concern in seed and seedling produclion since the occurrence of mixture with other linos, outcrossing and mutation is frequently encountered in the field. Until now, pure lines are being maintained using the observed morphological characteristics that requires a lot of time and effort and in turn do not give conclusive evidence. To solve this problem, we propose the utilization of DNA fingerprinting in maintaining rice varieties. In our previous study (Kubo et al. 1998) on the construction of Japonica rice linkage map, 64 RAPDs were identified from the screened 800 primers between Taicliung 65 and Nipponbare. DNA fingerprinting based on the identified RAPDs was applied in maintaining these varieties. Twenty Japanese varieties consisting of 16 non-glutinous and four glutinous Japanese varieties planted in Fukuoka Agricultural Research Center were used as planting matcrials in the succeeding experiment. Sixteen primers from the previous RAPD data were selected for DNA fingerprinting. Of 16 primers, a set of five primers yielding six reproducible markers were identified. These primers differentiated all the 20 varieties with less number of primer set. We tried to simplify and expedite the experiment by using simple method of DNA extraction and mini-gel electrophoresis system in DNA fingerprinting and we obtained scorable RAPD bands using this method. This result demonstrated that the closely related Japanese paddy rice varieties could be easily identified by utilizing the simplified RAPD technique.