Adaptability of Rhododendrons in high altitude habitats

Abstract

Tree species dominate many ecosystems throughout the world and their response to climate, in light of global warming, is a matter of primary concern. This review describes past and ongoing research in Rhododendron, an ecologically important and well-adapted genus of more than 1000 species, occupying diverse habitats. Research to date indicates survival ability and mechanisms, with an emphasis on cold tolerance. The capability of long-distance gene flow in these species increases their genetic variability which in turn enhances their adaptability to newer niches as well as to environmental gradients (mainly temperature). Attempts to explain the molecular basis of morphological and behavioural changes in Rhododendron against cold-induced damage has been made. Gradual advances in ‘omics’ have led to an enriched genomic resource dissecting the role and interaction of multiple molecular factors participating in cold adaptability. However, fewer genetic studies are available on species with an inherent or a default cold-tolerance ability. Considering this fact, understanding specific features of an adapted species can provide insights on overriding the effects of desiccation and determining phase transitions in other plants as well. We propose to integrate ecological and evolutionary studies with functional genomics to improve predictions of tree responses to their environment.

Keywords

Rhododendron / Adaptation / Frost / Growth / Geographical distribution

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