Geographic differences on accumulation of sugars and polyols in locust eggs in response to cold acclimation.
The accumulation of low molecular weight sugars and polyols is one of major mechanisms hypothesized to increase cold tolerance in overwintering insects. But little is known about whether these sugars and polyols are involved in geographic variation of cold tolerance. In this study, we investigated accumulation patterns of eight low molecular weight sugars and polyols of eggs in tropical and temperate populations of the migratory locust, which exhibits between-population variation in cold tolerance, in response to cold acclimation (5, 0 and -5 degrees C). Excluding erythritol, the other seven carbohydrates were identified as possible cryoprotectants in locust eggs. Basal maximal and minimal concentrations were 45 microg/g wet weight for trehalose and 0.59 microg/g wet weight for glycerol. Most sugars and polyols were elevated after a -5 degrees C exposure. In a tropical population, fructose, glucose, sorbitol and myo-inositol were significantly accumulated by low temperature treatments, but glycerol was not. In the temperate population, glycerol, glucose, mannitol, sorbitol, myo-inositol were significantly accumulated but trehalose did not increase. Our results suggest different accumulation patterns of these carbohydrates of locust eggs between tropical and temperate populations and highlighted possible roles for them in geographic variation of cold tolerance in the migratory locust.
Wang
X H
XH
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China.
Qi
X L
XL
Kang
L
L
D000064:Acclimatization / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D002241:Carbohydrates / Q000032:analysis; D002681:China; D002980:Climate; D003080:Cold Temperature; D003451:Cryoprotective Agents / Q000032:analysis; D005843:Geography; D006110:Grasshoppers / Q000502:physiology*; D010063:Ovum / Q000737:chemistry*; D011108:Polymers / Q000032:analysis
D002241:Carbohydrates; D003451:Cryoprotective Agents; D011108:Polymers; C024617:polyol