Evaluation of three common root extraction methods for Rotylenchulus reniformis recovery from cotton roots

Authors: Schumacher, Lesley; GRABAU, ZANE - University Of Florida

Submitted to: Plant Health Progress
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/24/2022
Publication Date: 8/22/2022
Citation: Schumacher, L.A., Grabau, Z.J. 2022. Evaluation of three common root extraction methods for Rotylenchulus reniformis recovery from cotton roots. Plant Health Progress. 1-4. https://doi.org/10.1094/PHP-11-21-0135-RS.
DOI: https://doi.org/10.1094/PHP-11-21-0135-RS

Interpretive Summary: Evaluation of three common root extraction methods for Rotylenchulus reniformis recovery from cotton roots: The reniform nematode is a pathogen of cotton that feeds upon roots, ultimately reducing cotton yield. Accurate diagnosis of reniform nematode infection within cotton roots is necessary for proper nematode management. However, methods to diagnosis nematode infection within roots are varied and inconsistent. Three common methods – blender, modified Baermann, and mist chamber – are used to extract nematodes from roots, but not in the same manner. The nematode life stage – egg, juvenile, or adult – recovered from cotton roots using these methods is dependent upon whether the method is active (modified Baermann funnel, mist chamber) or passive (blender). We showed which method worked the best to recover the various life stages of reniform nematode from cotton roots – the blender method for eggs and all three methods equally for juveniles/adults. Information from this study may be applied towards other plant systems to inform management decisions and be used by other researchers or diagnosticians.

Technical Abstract: Reniform nematode (Rotylenchulus reniformis) substantially impacts cotton production. Evaluating efficacy of management methods relies on accurate diagnosis of R. reniformis infection. Therefore, R. reniformis life stages (eggs and vermiform nematodes) were extracted from cotton roots at a long-term research site in Quincy, FL, USA in June 2017 and June 2018 and efficiency of three common root extraction methods (blender, modified Baermann funnel, and mist chamber) for R. reniformis recovery from cotton roots was evaluated. Due to its passive extraction nature, the blender method consistently recovered all R. reniformis life stages and also recovered the greatest overall abundances of R. reniformis life stages from cotton roots at midseason. Due to their active extraction natures, modified Baermann funnel and mist chamber methods were only successful at recovering vermiform R. reniformis life stages from cotton roots. This work highlighted the importance of understanding the limitations of commonly used extraction methods to increase accuracy of reniform nematode recovery from cotton roots and possible implications for nematode management decisions.