Optimization of RAPD Reaction System and Analysis of " HANGQIE-5 " Eggplant Generated by Space Mutagenesis

REN Chun-xiao; LIU Min; LU Jin-ying; WU Yu-huan

Abstract：Objective To analyze the new breeding of eggplant " HANGQIE-5" ( HQ-5) generated by space mutagenesis with RAPD, identify the differential RAPD bands, and try to provide molecular proofs for space mutation breeding. Methods Dry seeds of two eggplants " Tianshuichangqie ( TSCQ) " and Longguoyuanqie (LGYQ) were carried by "shenzhou-4" and "shenzhou-3"spaceship. Two mutant lines "TSCQ-MUT-4" and " LGYQ-MUT-4" were selected after four generations of self-cross of TSCQ and LGYQ. A new variety of " HQ-5" was selected by crossing the two lines of "TSCQ-MUT-4" and "LGYQ-MUT-4" , which were male and female, respectively. The RAPD reaction system was optimized with orthogonal design and further RAPD analysis was applied. Results The RAPD reaction system was determined as follows; DNA; 40 ng, dNTPs; 7.5 nmol, primer; 10 ng, and rTaq polymerase; 1.25 U. The RAPD results displayed that TSCQ-MUT-4 produced four differential bands compared with its wild type, while LGYQ-MUT-4 produced one, through space flight. Six differential fragments were amplified between HQ-5 and the paternal/maternal. HQ-5 not only shared the common fragments with its parents, but also held some particular ones, which were stably inherited. Conclusion The results indicate that space mutagenesis could cause mutations in DNA of plants, and is helpful to generate a new breeding.