PROPERTIES OF MATERNAL HAPLOID MAIZE PLANTS AND POTENTIAL APPLICATIONTO MAIZE BREEDING

Presented are the results of a two-year study of haploid maize plants in the field. The haploids were produced with the aid of inducer line ZMS. In total, 604 and 1030 haploids were obtained and studied in the first and second years, respectively. Tassels of haploid plants were f ound to be almost completley sterile. Fertility of ears was studied by pollinating them with the pollen from diploid inbred lines, the cross resulting in almost all of the haploid ears carrying kernels. On aver age 27.4 kernels per ear of haploid plant were obtained in the first y ear of study and 26.3 in the second. These gave rise to normal diploid plants. This property allows genotypes selected at the level of haplo id plants to be involved in breeding process. Unusual plants were foun d among haploids, phenotypically resembling homozygous lines. It was a ssumed that the plants had resulted from spontaneous chromosome doubli ng in haploids. The results of comparative studies of progenies of unu sual plants and inbred lines derived from the same synthetic populatio n are presented.