Based on the established technique for Bromeliaceae shoot regeneration, the test-tubeseedlings were treated with EMS and screened by HYP to induce the cold-tolerant mutantsof Bromeliaceae.

Screening the resistant mutants to banana vascular wilt using the crude toxins of Fusarium oxysporum f.sp.cubense;

Progress on the selection in vitro and test of resistant mutant on the plants;

We isolated 8 putative MeIAA-resistant mutants and carried out further experiments on one mutant,mir1.

Physiological characters of the resistant mutant of Xanthomonas citri to amicarthiazol;

Biological properties of resistant mutants of Xanthomonas oryzae to Saikuzuo;

Comparisons of the nucleotide sequence of the partial cytochrome b(cyt b) gene from sensitive isolates and resistant mutants revealed that all three resistant mutants had a single point mutation of GGT(in sensitive isolates) to GCT(in resistant mutants),which caused a change of glycine(Gly) to an alanine(Ala) at codon position 143(G143A) of the cyt b.