Assessment Of Genetic Stability Between Maize (Zea Mays L.) Haploid Induced By Inducer And Its Parents

Maize plays an important role in food security as an important food and forage crop in the world.Haploid breeding has been one of the important techniques in the modern maize breeding,which can greatly shorten the years of breeding.Maize parthenogenesis inducer lines induce haploid which contain 4 vital elements is an significant way of haploid breeding,including inducer line breeding,haploid inducing,haploid identification and doubling.Many years ago,maize haploid induction was discovered and applied to practice,but its induction mechanism is still unknown.Aiming at probe into the breeding of inducer in theory,this study analyzed the genetic stability between haploid and its parents combined haploid induction and molecular markers,explored induce mechanism and regularity.This paper got the haploids from the cross Z58×Zhongyouyu 1 and C7-2×zhongyouyu 1 through field planting,and Zhongyouyu 1was selected as inducer in our laboratory.We confirmed the haploids by color identification,root chromosome counting,appraisal of flow cytometry and field shape identification.We used AFLP molecular marker to analysis genetic diversity between the haploids and their parents.The main results were as follows:We analyzed Z58×Zhongyouyu 1 and Z58 haploids by AFLP molecular marker:(1)We found 418 clear bands between Z58 haploids and their parents,including 358 common bands(85.65%)and 60 specific bands(14.35%).Among the 60 specific bands,the bands that haploids appeared or disappeared specifically were 11(18.33%),the bands that haploids and their female appeared or disappeared simultaneously were 46(76.67%),and the bands that haploids and their inducer appeared or disappeared simultaneously were only 3(5.00%).(2)Compared with Z58,all of the haploids had 10 new bands and 4 missing bands accounting for 3.35%,while the variation frequency between individual plant of Z58 haploid and its female was 0.5%-1%.We analyzed C7-2×Zhongyouyu 1 and C7-2 haploids by AFLP molecular marker:(1)We found 407 clear bands between C7-2 haploids and their parents,in-cluding 339 common bands(83.30%)and 68 specific bands(16.70%).Among the 68 specific bands,the bands that haploids appeared or disappeared specifically were 14(20.59%),the bands that haploids and their female appeared or disappeared simultaneously were 49(72.06%),and the bands that haploids and their inducer appeared or disappeared simultaneously were only 5(7.35%).(2)Compared with C7-2,all of the haploids had 5 new bands and 14 missing bands accounting for 4.67%,while the variation frequency between individual plant of Z58 haploid and its female was 0.01%-0.02%.In conclusion,haploid induced by inducer and its parents existed following genetic instability phenomenon: haploids emerged infiltration fragment of inducer,haploids genome mutated randomly.