Heritability of flower size and heat stress in diploid roses Academic Article uri icon


  • 2019 International Society for Horticultural Science. All Rights Reserved. Heat stress on roses (Rosa spp.) negatively affects the plants performance and reduces the market value of the crop. The effect of heat on flower size was assessed through petal number in the field during the cool (~20C) and warm (~30C) seasons during 2013-2014 and through flower diameter and weight during 2015 for 9 interrelated diploid rose families, respectively. The elevated temperature caused a decrease in flower size for flower diameter (~16-18%), petal number (~23-17%), and flower weight (~17-32%). Flower size showed low to moderate (flower diameter, 0.24-0.38; petal number, 0.12-0.26; flower weight, 0.34-0.53) narrow sense heritability and moderate (flower diameter, 0.62-0.70; petal number, 0.74-0.91; flower weight, 0.76-0.88) broad sense heritability inferring a major non-additive genetic component for flower size. Differences in heat tolerance would indicate that roses respond differentially to the environment (heat stress). Thus in a genetic variance analysis, a high GE variance would indicate genetic differences in heat stress. Among the three size parameters, flower diameter showed the largest GE genetic variance. However, the GE variance for flower diameter in the heat shock experiment explained less (6.3%) genetic variance as compared to the field experiment (37%) indicating that selection would be more effective under field conditions. We are now investigating the use of FlexQTL to analyze the phenotypic and genotypic data from these interrelated families to identify important QTL conditioning the changes in flower size and heat tolerance.

published proceedings


author list (cited authors)

  • Lau, J., Liang, S., Wu, X., Yan, M., Klein, P. E., Young, E. L., & Byrne, D. H.

citation count

  • 2

complete list of authors

  • Lau, J||Liang, S||Wu, X||Yan, M||Klein, PE||Young, EL||Byrne, DH

publication date

  • February 2019