title: Implications of High Temperature and Elevated CO2 on Flowering Time in Plants.
abstract: Flowering is a crucial determinant for plant reproductive success and seed-set. Increasing temperature and elevated carbon-dioxide (e[CO2]) are key climate change factors that could affect plant fitness and flowering related events. Addressing the effect of these environmental factors on flowering events such as time of day of anthesis (TOA) and flowering time (duration from germination till flowering) is critical to understand the adaptation of plants/crops to changing climate and is the major aim of this review. Increasing ambient temperature is the major climatic factor that advances flowering time in crops and other plants, with a modest effect of e[CO2].Integrated environmental stimuli such as photoperiod, temperature and e[CO2] regulating flowering time is discussed. The critical role of plant tissue temperature influencing TOA is highlighted and crop models need to substitute ambient air temperature with canopy or floral tissue temperature to improve predictions. A complex signaling network of flowering regulation with change in ambient temperature involving different transcription factors (PIF4, PIF5), flowering suppressors (HvODDSOC2, SVP, FLC) and autonomous pathway (FCA, FVE) genes, mainly from Arabidopsis, provides a promising avenue to improve our understanding of the dynamics of flowering time under changing climate. Elevated CO2 mediated changes in tissue sugar status and a direct [CO2]-driven regulatory pathway involving a key flowering gene, MOTHER OF FT AND TFL1 (MFT), are emerging evidence for the role of e[CO2] in flowering time regulation.
authors.affiliation: International Rice Research InstituteMetro Manila, Philippines; Department of Agronomy, Kansas State UniversityManhattan, KS, USA.
authors.forename: S V Krishna
authors.initials: SV
authors.lastname: Jagadish
authors.affiliation: International Rice Research Institute Metro Manila, Philippines.
authors.forename: Rajeev N
authors.initials: RN
authors.lastname: Bahuguna
authors.affiliation: Department of Agronomy, Kansas State University Manhattan, KS, USA.
authors.forename: Maduraimuthu
authors.initials: M
authors.lastname: Djanaguiraman
authors.affiliation: International Rice Research Institute Metro Manila, Philippines.
authors.forename: Rico
authors.initials: R
authors.lastname: Gamuyao
authors.affiliation: Department of Agronomy, Kansas State University Manhattan, KS, USA.
authors.forename: P V Vara
authors.initials: PV
authors.lastname: Prasad
authors.affiliation: International Maize and Wheat Improvement Centre (CIMMYT) Nairobi, Kenya.
authors.forename: Peter Q
authors.initials: PQ
authors.lastname: Craufurd
keywords: climate change; elevated CO2; flowering regulation; flowering time; high temperature; tissue temperature