Induction of chromosome aberrants in rice (Orgza sativa L.) by using irradiated pollen

Rice stocks carrying one or more recessive marker genes were fertilized with pollen of a stock carrying normal alleles at the corresponding loci, that had been preirradiated with gamma rays. Plants derived from such hybridization were investigated for their marker genes, morphological features and seed fertility. Fifty-two pseudo-dominant plants for 9 marker genes were detected from 13,063 plants of 10 cross combinations, and a number of other plants that did not show pseudo-dominant for any marker genes but had variations in morphological features and/or seed fertility, were also obtained. The chromosome number of those plants were counted in the root tip cells, and plants with 2n= 12, 2n=23, 2n=23+1Fr (fragment chromosome), 2n=23+2Fr, 2n=23+3Fr, 2n=25, and chromosome interchange heterozygous, were observed. This study suggests that the use of irradiated pollen is an effective method for inducing chromosome aberration, such as chromosome deficiency, monosomics and chromosome interchange in rice (Oryza sativa L.)