Screening of thermo sensitive genetic male sterility (TGMS) lines of diploid cotton (Gossypium arboreum L.) for critical temperature for sterility and fertility point.

摘要

Male sterility is an effective mean of producing hybrid cotton since it does not need labour intensive hand emasculation and pollination. In cotton, mainly two types of male sterility systems viz., Cytoplasmic Genetic Male Sterility (CGMS) and Genetic Male Sterility (GMS) systems could be used for hybrid seed production. GMS is preferred than CGMS as it overcomes the drawbacks of cytoplasmic effect and problem of fertility restoration. Thermo Sensitive Genetic Male Sterility (TGMS) is a two line method of hybrid seed production where the sterile flowers are converted into fertile and fertile into sterile at a particular temperature. Once this is stabilized it is possible to convert any elite variety into TGMS and develop heterotic hybrids. TGMS system in Gossypium arboreum and photoperiod sensitive genetic male sterility (PGMS) system in G. hirsutum has been identified for the first time. The line remains sterile till temperature reaches 24 degrees C and show complete pollen fertility at temperature less than 18 degrees C. PGMS lines in G. hirsutum show complete pollen sterility when temperature rises above 40 degrees C for continuous period of time. Present investigation is first kind of report of TGMS based cotton hybrids in diploid cotton.