Refine
Year of publication
- 2019 (2) (remove)
Document Type
- Article (2)
Language
- English (2)
Has Fulltext
- yes (2)
Is part of the Bibliography
- no (2)
Keywords
- Solanum (2) (remove)
Institute
The Palearctic flea beetle Epitrix pubescens (Koch) (Coleoptera: Chrysomelidae: Galerucinae: Alticini) is reported as established in North America. It is recorded in the United States from Illinois, Massachusetts, New Hampshire, New York, Oregon, and Wisconsin, and in Canada from the Provinces of Nova Scotia, Ontario, and Quebec. The oldest records are from 1975. The species has been reported feeding on Solanum dulcamara L. (Solanaceae). Full distributional information and reference photos for identification are provided. Epitrix pubescens may have avoided detection for such a long time due to its size, difficulty of identification, and affinity for a weed rather than agricultural crops. The more than 40-year lag between arrival and discovery of an immigrant species illustrates the importance of routine biodiversity monitoring efforts and taxonomic works.
Summary
Wild relatives of crops thrive in habitats where environmental conditions can be restrictive for productivity and survival of cultivated species. The genetic basis of this variability, particularly for tolerance to high temperatures, is not well understood. We examined the capacity of wild and cultivated accessions to acclimate to rapid temperature elevations that cause heat stress (HS).
We investigated genotypic variation in thermotolerance of seedlings of wild and cultivated accessions. The contribution of polymorphisms associated with thermotolerance variation was examined regarding alterations in function of the identified gene.
We show that tomato germplasm underwent a progressive loss of acclimation to strong temperature elevations. Sensitivity is associated with intronic polymorphisms in the HS transcription factor HsfA2 which affect the splicing efficiency of its pre‐mRNA. Intron splicing in wild species results in increased synthesis of isoform HsfA2‐II, implicated in the early stress response, at the expense of HsfA2‐I which is involved in establishing short‐term acclimation and thermotolerance.
We propose that the selection for modern HsfA2 haplotypes reduced the ability of cultivated tomatoes to rapidly acclimate to temperature elevations, but enhanced their short‐term acclimation capacity. Hence, we provide evidence that alternative splicing has a central role in the definition of plant fitness plasticity to stressful conditions.