title: Temperature-sensitive phenotype caused by natural mutation in Capsicum latescent in two tropical regions.
abstract: Plants in tropical regions experience temperature fluctuation only in non-extreme ambient temperatures. Thus, moderate changes in temperatures, which they never experience in their local environments, might be sufficient to manifest the locally hidden phenotype caused by natural mutation. To validate this hypothesis, temperature-treating experiments were performed on Capsicum accessions collected from tropical regions. Thirty-six Capsicum accessions, collected from Caribbean countries, were screened for temperature sensitivity. Similarities in their temperature sensitivities were compared with Sy-2 (C. chinense) from Seychelles, which was previously found to be a temperature-sensitive accession. Tr-13 from Trinidad & Tobago exhibited developmental abnormalities at temperatures below 24 °C. Expression of defense-related genes was induced, and salicylic acid, which is a key molecule in the plant's defense response, accumulated in Tr-13 at temperatures below 24 °C. Tr-13 and Sy-2 appeared normal when they were grown at temperatures simulating those in Trinidad and Seychelles, respectively. Crossing Tr-13 with No. 3341 or Sy-2 revealed that the temperature-sensitive phenotype of Tr-13 was caused by a genetic mutation in the same locus as Sy-2. Plants having a temperature-sensitive phenotype that is caused by natural mutations evade artificial selection and exist as crops in specific environments, such as tropical regions.
authors.affiliation: Graduate School of Agriculture, Kyoto University, Takatsuki, Osaka, Japan. koeda@kais.kyoto-u.ac.jp
authors.forename: Sota
authors.initials: S
authors.lastname: Koeda
authors.forename: Munetaka
authors.initials: M
authors.lastname: Hosokawa
authors.forename: Hiroki
authors.initials: H
authors.lastname: Saito
authors.forename: Motoaki
authors.initials: M
authors.lastname: Doi
mesh_terms: D002212:Capsicum / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D017691:Caribbean Region; D009154:Mutation; D010641:Phenotype; D010802:Phylogeny; D018515:Plant Leaves / Q000145:classification / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D020156:Salicylic Acid / Q000032:analysis / Q000378:metabolism*; D013696:Temperature; D014329:Tropical Climate
chemical_list: D020156:Salicylic Acid