title: The Genetic Control of Reproductive Development under High Ambient Temperature.
abstract: Ambient temperature has a large impact on reproductive development and grain yield in temperate cereals. However, little is known about the genetic control of development under different ambient temperatures. Here, we demonstrate that in barley (Hordeum vulgare), high ambient temperatures accelerate or delay reproductive development depending on the photoperiod response gene PHOTOPERIOD1 (Ppd-H1) and its upstream regulator EARLY FLOWERING3 (HvELF3). A natural mutation in Ppd-H1 prevalent in spring barley delayed floral development and reduced the number of florets and seeds per spike, while the wild-type Ppd-H1 or a mutant Hvelf3 allele accelerated floral development and maintained the seed number under high ambient temperatures. High ambient temperature delayed the expression phase and reduced the amplitude of clock genes and repressed the floral integrator gene FLOWERING LOCUS T1 independently of the genotype. Ppd-H1-dependent variation in flowering time under different ambient temperatures correlated with relative expression levels of the BARLEY MADS-box genes VERNALIZATION1 (HvVRN1), HvBM3, and HvBM8 in the leaf. Finally, we show that Ppd-H1 interacts with regulatory variation at HvVRN1. Ppd-H1 only accelerated floral development in the background of a spring HvVRN1 allele with a deletion in the regulatory intron. The full-length winter Hvvrn1 allele was strongly down-regulated, and flowering was delayed by high temperatures irrespective of Ppd-H1 Our findings demonstrate that the photoperiodic and vernalization pathways interact to control flowering time and floret fertility in response to ambient temperature in barley.
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (M.E., M.v.K.).|Institute of Plant Genetics, Heinrich-Heine-University, 40225 Düsseldorf, Germany (M.E., M.v.K.); and.|Cluster of Excellence on Plant Sciences "From Complex Traits towards Synthetic Modules," 40225 Düsseldorf, Germany (M.v.K.).
authors.forename: Mahwish
authors.identifier: 0000-0002-3857-5665
authors.initials: M
authors.lastname: Ejaz
authors.affiliation: Max Planck Institute for Plant Breeding Research, D-50829 Cologne, Germany (M.E., M.v.K.); korff@mpipz.mpg.de.|Institute of Plant Genetics, Heinrich-Heine-University, 40225 Düsseldorf, Germany (M.E., M.v.K.); and korff@mpipz.mpg.de.|Cluster of Excellence on Plant Sciences "From Complex Traits towards Synthetic Modules," 40225 Düsseldorf, Germany (M.v.K.) korff@mpipz.mpg.de.
authors.forename: Maria
authors.identifier: 0000-0002-6816-586X
authors.initials: M
authors.lastname: von Korff
mesh_terms: D000483:Alleles; D056926:CLOCK Proteins / Q000235:genetics / Q000378:metabolism; D002940:Circadian Rhythm / Q000235:genetics; D035264:Flowers / Q000235:genetics / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D005799:Genes, Dominant; D017343:Genes, Plant; D014644:Genetic Variation; D005838:Genotype; D001467:Hordeum / Q000235:genetics* / Q000502:physiology*; D006358:Hot Temperature; D056626:Inflorescence / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D012098:Reproduction / Q000235:genetics; D012639:Seeds / Q000235:genetics / Q000502:physiology; D013997:Time Factors
chemical_list: D010940:Plant Proteins; D056926:CLOCK Proteins