Techniques to Conduct Morphological and Molecular Investigations on Nematodes

Abstract

The intriguing variety in the form and size of roundworms leading free-living as well as parasitic life has mesmerized scientists world over. One most common happening during developmental cycle of roundworms is moulting, and this characteristic is remarkably retained irrespective of the presence or absence of intermediate hosts (direct life cycle) in the life cycle of round worms in certain specified cases. The application of fixatives, in particular, therefore becomes a challenging exercise to suit the body form at different stages of development. However, looking at the severity of pathogenic influence of animal-parasitic and plant-parasitic nematodes necessitated appropriate fixation procedures of these worms infesting separate variety of hosts. Such procedures are enumerated in the text of this chapter with meticulous details on morphology based on scanning electron microscopic examination of certain worms, wherever required. Prominent techniques with molecular applications in taxonomy of roundworms to segregate arthropod-parasitic, freshwater, marine, and soil taxa have been outlined. The methods for effective barcode analyses of these round worms from terrestrial or aquatic vertebrate hosts have been discussed briefly.