Management of the ig gene for haploid induction in maize

Abstract

The effect of the ig gene showed the same intensity at the haploid as at the diploid level. This was contrary to the results on the exceptional rate obtained elsewhere, and suggested that haploid manipulation should not be used as a routine procedure. At the diploid level, the genetic background of the ig gene has a strong effect in paternal haploid induction. In backcrosses of W23 ig as the initial source with recurrent inbred lines which were more or less related to the Golden Glow OP origin, pleiotropic effects differed according to the genetic background in the offspring. If male sterility observed at the homozygous stage was still present, the other effects were completely lost from the initial cross with lines of the same origin (W25, CG3). On the other hand, they were maintained at a similar level in backcrosses with some non-related linos (F1254 for polyembryony). Due to its earliness the C0220 inbred line, in which the ig gene manipulation procedure is of interest, was shown to maintain a fairly good level of haploid induction in backcross and appears to be a promising background. © 1992.