Combining Ability of Response to Photoperiod in Peanut uri icon

abstract

  • Photoperiod insensitivity plays an important role in the adaptationof peanut (Arachis hypogaea L.) genotypes across environments.Howeverl,i ttle is knowno f its genetic control. Theo bjective of thisstudy was to determine the combining ability of response to photoperiodin peanut. The Ft progenies from a six-parent diallel cross excludingreciprocals were studied together with their parents for responseto photoperiod under short and long day conditions in the field forthree seasons. The experimentw as conductedi n a split plot design withphotoperiod as main plots and genotype as subplots. The response tophotoperiod (Dst) was computed as the difference in harvest index(adjusted pod weight/adjusted biomass) between short and long daytreatments. The mean square for response to photoperiod was highlysignificant for parents and their crosses. Season by cross interactionwas the only significant interaction effect. The response to photoperiodwas mainly associated with general combining ability variance.ICG2 405 and ICGV8 6031 were good general combiners for insensitivityto photoperiod. All crosses of sensitive × sensitive andsensitive × insensitive parents were sensitive to photoperiod. However,in several cases, this response was not consistent across seasonsand resulted in a significant season × cross interaction. The F1 betweeninsensitive parents was insensitive to photoperiod in the three seasonstested. A comparison of Ft response with parents and midparentvalue of crosses between photoperiod sensitive and insensitive parentssuggested additive gene action in some crosses and partial dominanceto dominance in others

publication date

  • 1997
  • 1997