A MUTATION AT AP2 LOCUS OF ARABIDOPSIS CONFERS SPERMINE RESISTANCE

A spermine-resistant mutant of Arabidopsis thaliana (L.) Heynh. was is olated from M-2 population of ethylmethanesulphonate-mutagenized seeds . The mutant was resistant to seed germination inhibition by spermine, but was as sensitive as the wildtype to spermidine and putrescine. In addition, the mutant displayed developmental abnormalities such as fr equent cauline leaves, increased number of branches with inflorescence , reduced apical dominance, flowers subtended by bracts, disrupted flo ral organs with homeotic conversions. Genetic analysis indicated a sin gle recessive nuclear mutation that was allelic to apetala2-1 (AP2-1). The new mutant allele of AP2 locus was accordingly numbered as AP2-10 .