Association of high-frequency origin of late leaf spot resistant mutants with AhMITE1 transposition in peanut

摘要

With 1 figure and 1 table VL1 is a peanut mutant with resistance to rust and susceptibility to late leaf spot (LLS). Upon ethyl methane sulphonate mutagenesis it generated high frequency of independent, but morphologically similar mutants, which were resistant to LLS and susceptible to rust. Generation of such mutants could not be fully explained through segregation analysis. Molecular analysis showed that the origin of mutant 28-2, 45 and 110 was associated with the insertion of Arachis hypogaea miniature inverted-repeat transposable element (AhMITE1) at a predetermined site (FST1-linked site). Subsequent spontaneous mutation in these three mutants generated variants [28-2(s), 45(s) and 110(s)]. They were susceptible to both LLS and rust. Origin of such variants was associated with the excision of AhMITE1 from FST1-linked site, indicating its active role in high-frequency origin of LLS resistant mutants in peanut.