Wheat Ppd-1 allelic combination modulates photoperiod sensitivity

Abstract

ABSTRACT: a model linking Ppd-1 allelic composition to photoperiod response curve would allow replacing expensive and time consuming phenologic trials. In Ppd-1 near isogenic lines grown under different photoperiods we observed that Ppd-1a “insensitivity” alleles decreased photoperiod sensitivity for the whole cycle to anthesis, with negligible effect on threshold photoperiod or intrinsic earliness. Photoperiod sensitivity for the first half of the cycle (emergence to onset of stem elongation) responded similarly. Photoperiod response for the second half (onset of stem elongation to anthesis) was milder. After validation, this model would allow to predict photoperiod response of any genotype, given its Ppd-1 allelic combination.