Morphological characteristics and identification of new monosomic stocks for cotton (Gossypium hirsutum L.)

The presence of distinct morphological markers in monosomics is important for selection and maintenance of the monosomic plants in subsequent generations and for a well-targeted chromosome substitutions. Here we present cytological and morphological features of the cotton (Gossypium hirsutum L.) monosomic lines developed in Uzbekistan, and their identification by means of translocation tests. We report “reduced” stigma as a new phenotypic marker for cotton monosomics, which makes it possible to distinguish cytotypes without cytological analyses. We identified eleven cotton monosomes by translocation tests using our 28 translocation cotton lines. We determined such features of the cotton monosomic lines as significant lowering of the pollen fertility, genetic determination of variation in pollen fertility in different flowers of the same monosomic plants and variation of both meiotic index and tetrads with micronuclei in different buds. New features of cotton monosomic lines, described herein, should be useful for future cotton genome investigation and development of new chromosome substitution lines.