HE cause and nature of chromosomal alterations has become an imT portant genetic problem since it has been shown that both mutation and speciation often are associated with structural alterations of the chromosomes (DOBZHANSKY 1937). The frequency of spontaneous structural changes is too low in most organisms to permit a statistical analysis of types or frequencies of alterations, although rece...

Storage protein gene expression, characteristic of mid- to late embryogenesis, was investigated in microspore embryos of rapeseed (Brassica napus). These embryos, derived from the immature male gametophyte, accumulate little or no detectable napin or cruciferin mRNA when cultured on hormone-free medium containing 13% sucrose. The addition of abscisic acid (ABA) to the medium results in an incre...

Abstract Induced mutations are important for genetic research and breeding. Mutations induced by physical or chemical mutagenesis usually heterozygous during the early generations. However, must be fixed prior to phenotyping field trials, which requires additional rounds of self-pollination. Microspore culture is an effective method produce double-haploid (DH) plants that homozygotes. In this s...

The method for regeneration of plants from microspores was being developed for the last 50 years. Through the use of this method a tremendous progress in breeding of many important crop plants was achieved. This applies to cereals too. We have developed microspore culture techniques for many cereals and grasses, and here we recommend androgenesis as a tool to study morphological and biochemical...