title: An Opposite Pattern to the Conventional Thermal Hypothesis: Temperature-Dependent Variation in Coloration of Adults of Saccharosydne procerus (Homoptera: Delphacidae).
abstract: Melanism is a common polymorphism in many insect species that also influences immune function. According to the thermal melanin hypothesis, ectothermic individuals from cooler environments have darker cuticles and higher polyphenol oxidase (PO) levels, which represent a better immunocompetence. In this study, the links among environmental temperature, melanism, and PO activity of Saccharosydne procerus (Matsumura) were examined. Most S. procerus have a black spot on their forewings at high temperatures in the field and in the laboratory. In PO activity assay, a positive association between PO level and temperature was found. Our results showed that a diversification of melanism occurred under different temperatures and that melanism in S. procerus presented an opposite pattern to the one proposed by the thermal hypothesis.
authors.affiliation: College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Haichen
authors.initials: H
authors.lastname: Yin
authors.affiliation: College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Shakeel
authors.affiliation: Wuhan Vegetable Research Institute, Wuhan, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Kuang
authors.affiliation: College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Jianhong
authors.initials: J
authors.lastname: Li
mesh_terms: D000818:Animals; D004156:Catechol Oxidase / Q000378:metabolism*; D006430:Hemiptera / Q000201:enzymology*; D006358:Hot Temperature; D019476:Insect Proteins / Q000378:metabolism*; D008954:Models, Biological; D010858:Pigmentation / Q000502:physiology*; D014921:Wings, Animal / Q000201:enzymology
chemical_list: D019476:Insect Proteins; D004156:Catechol Oxidase