An Ion-beam induced balancer chromosome in Arabidopsis

坂本 綾子; Vo, L.*; 秋田 睦; 長谷 純宏

no journal, , 

Ion beams induce large chromosome alterations as well as small mutations i.e. base changes or frameshifts, and thus are effective tools for mutation breeding to create novel characters on crops. Here we describe another example of ion-beam induced chromosome alteration and its possible application. A UV-sensitive Arabidopsis mutant shows reduced fertility and abnormal recombination rate when crossed to wildtype plant. Sequence analysis revealed that 1/3 of the ch. 3 was translocated to the ch. 2 in , which disrupted gene, causing an NER deficiency. To test if the chimera chromosome can behave like a balancer chromosome, we crossed to and examined segregation of those in F2. In 180 chromosomes, a genetic marker on the top of ch. 3 was completely linked with the marker at the center of ch. 3 without recombination through 7 Mb region. Screening of F2 plants negative for both UV sensitivity and phenotype could easily identify heterozygotes for or any other alleles on this 7 Mb region. Thus, ion beams are also useful for chromosome engineering such as making balancer chromosomes that make easier to maintain a line of interest over the generation.