Characterization of a cotton interspecific hybrid of American cotton with wild species G. armourianum

Abstract

Wild species constitute a source of valuable genes for many adverse climatic conditions, disease and pests. To match up the level of quick depleting insect pest and disease resistance and fast evolving pests, it is the urge of the hour to broaden the resistance base. In order to achieve this goal in cotton, wide hybridization was performed between G. hirsutum (AADD) cv. MCU5, CO14 and CO17, and G. armourianum and interspecific hybrids developed were characterized for several morphological characters for obtaining an idea about the status of the various traits. Interspecific hybrid developed with all three G. hirsutum varieties are potential lines for future introgression programs of insect and disease resistance along with other useful traits. The F1 hybrid displayed intermediate expression for most of the traits. Traits like colour of the stem, leaf colour, position of stigma, nectarines of hybrid completely resembled wild parent-and are considered as dominant in expression. The petal spot was present in the hybrid similar to that wild parent, unlike the cultivated parent; this appeared with different levels of intensity in F1 along with other characters like colour of the anther, and filament colour. Hybrids had profuse flowering throughout the year with low pollen load and pollen of variable shape and size expressing sterility to partial fertility. Noteworthy differentiation was seen between the leaf size and size of other plant parts of the hybrid.