DNA Barcoding: Implications in Plant–Animal Interactions

Abstract

Trophic interactions between plants and animals occur through various ecological processes such as pollination, frugivory, and herbivory. Among the three, pollination and frugivory represent the mutualistic interactions and the herbivory represents a negative antagonistic interaction. Interaction with pollinators and frugivores are statutory for many plants for the dispersal of gametes and offspring, respectively. On the contrary, the herbivory plays a substantial role in maintaining the stability of floral communities. Disruption in these natural species interactions can have detrimental effect on both the interacting species and other species of higher trophic levels, which eventually destabilizes the terrestrial ecosystem. Thus, a thorough perception of the interacting species is imperative for the restoration of bio-communities and conservation of ecosystems. Although, plant-animal interactions had been identified traditionally through field observation and tracking the movement of plant visitors, they are inadequate in accurately determining the interacting species as interaction occurs in the vicinity of other co-occurring plants and animals. Similarly, histological and biochemical analyses of gut matter and feces of herbivores/frugivores are not adequate to accurately identify the plant sources that the animals are depending upon. Paucity of an appropriate methodology has been always a limitation in delineating full range of plant-animal interactions. DNA barcoding technique has revolutionized the field of community ecology. Its unprecedented accuracy and speed has made it, ideally the best method of choice for identifying plant-animal interactions at species and population levels. DNA barcoding regions rbcL, matK, trnH-psbA, trnL, ITS2 (plant), and COI (animal) are the most common markers used in identifying plant and animal species. These barcodes have been adapted to characterize various plant and animal sources (honey, pollen, gut content, and feces) for unraveling many of the unnoticed trophic associations existing between plants and animals.