A Comparative Study of Three Widespread Methods for Extracting Plant-Parasitic Nematodes from Soil Samples

Abstract

This study was conducted in a productive farm characterized by heterogeneous soil type and planted with Balaika bananas (Musa maghrabi) in Al-Sharkia Governorate, Egypt. Three soil types namely sandy, sandy clay, and clayey soil were determined in this farm. Three methods were selected for extracting plant-parasitic nematodes present in the previous soil types. These methods were extraction trays (ET), decanting plus sieving (DS) and centrifugal flotation (CF) methods. Results showed that the centrifugal flotation was the most efficient extraction method. The relative efficacy of the extraction (%) in the DS method was 36.76 and 39.29% in sandy clay and clayey soil, respectively while, in the CF method it was 35.94% in clayey soil type, for genus Meloidogyne. The inactive nematode genera e.g. Criconemoides was not extracted by ET and DS methods in sandy and sandy clay soil types. The most efficient method for extracting this genus was the CF method it recorded 51.82 and 47.77% in sandy and clayey soil types, respectively. In this comparative study it could be concluded that the centrifugal flotation method (CF) was the most efficient method for extraction the sluggish and motile nematodes, take short time for extraction, and the final suspension was clear. On the other hand, the ET method using a small amount of water had an importance today in water management strategy.