Photoperiod-sensitivity genes (Ppd-1): Quantifying their effect on the photoperiod response model in wheat

PÉREZ-GIANMARCO, THOMAS I; SEVERINI, ALAN D; GONZÁLEZ, FERNANDA G

JOURNAL OF EXPERIMENTAL BOTANY

OXFORD UNIV PRESS

Año: 2019 vol. 7 p. 1185 - 1198

0022-0957

Coupling anthesis date to the most suitable environmental conditions is critical for wheat (Triticum aestivum L.) adaptation and yield potential. Development to anthesis is controlled by temperature and photoperiod. Response to photoperiodis chiefly modulated by Ppd-1 genes, but their effect on the quantitative response to photoperiod of (i) time to anthesis and (ii) pre-anthesis phases remains largely unknown. A photoperiod-sensitive spring cultivar, Paragon, andnear-isogenic lines of it carrying different combinations of Ppd-1a insensitivity alleles were tested under a wide range of photoperiods, including switches in photoperiod at the onset of stem elongation. Using multimodel inference we found that Ppd-1a alleles reduced photoperiod sensitivity of (i) emergence to anthesis and (ii) emergence to onset of stem elongation, both in a less than additive manner, while threshold photoperiod and intrinsic earliness were unaffected.Sensitivity to current photoperiod from onset of stem elongation to flag leaf and from then to anthesis wasmilder than for previous phases and was not related to variability in Ppd-1. However, ?memory? effects of previouslyexperienced photoperiod on the duration from onset of stem elongation to flag leaf were related to variability in Ppd-1. The characterization and quantification provided here of the effects on development of Ppd-1 allelic combinationsshould help increase accuracy of genotype-to-phenotype models in predicting wheat phenology.