Reproductive abnormalities in interspecific crosses involving Gossypium hirsutum and Gossypium arboreum

A successful cross fertilization involving two different species implies that a chain of reproductive process takes place unhampered after pollination. The coordination and interaction between genes or gene complexes in the pollen parent and matching gene or gene complexes in the pistil parent should be hormonious. Understanding of pollen tube growth and pollen attrition is revealed from the study of pollen-pistil interaction and for understanding the function of components specifically accumulated in the transmitting tissue cell wall and intercellular matrix that may interact with pollen tube. The role of the pistil in inhibiting incompatible pollen is well known and has been extensively investigated. Apart from arrest of the pollen tube at different levels, several abnormalities like twisting and bulging of the pollen tube, knot formation in pollen tube, lateral enlargement of pollen tube and growth of pollen tube in opposite direction were noticed. In the present study, an attempt was made to study the pollen and pistil traits between parents and crosses of three cultivated American cotton and six diploid desi cotton. Palynological features were interpreted to determine the extent of incompatibility in triploids generated.