ABSTRACT

The development of an interface between cotton cytogenetics and the cotton genomic mapping effort reflects a need to interrelate previously obtained information about genomes of cotton and its close relatives with the rapidly emerging genomic map of molecular markers. Historically obtained information provides a crude picture of what is required to map the genomes of Upland and Pima cottons, and what we will perceive from the map. Development of the interface presently relies heavily on hybrid procedures involving well-established gel-based methods and cytogenetic manipulations. An increased involvement of molecular cytogenetic is predicted, as new techniques are forthcoming. The genomic, genetic, cytogenetic, and physical maps will relate to each other as the interface expands, with mutual benefits to each. One of the most immediate applications of a genomic map will be interspecific introgression. If the potential utility of the genomic map is to be harnessed for genetic improvement, the prevalence of epistatic effects over cryptic beneficial alleles needs broad recognition. Justification for germplasm introgression should be based on empirical genetic comprehension, rather than merely on perceptible qualities of wild germplasm. Sustained support is needed for projects devoted to germplasm introgression from diploid species to the cultivated tetraploids.