Response of potato cultivars to the northern root-knot nematode, Meloidogyne hapla, under field conditions in New York State, USA

• Published in: Nematology : international journal of fundamental and applied nematological research Vol. 23; no. 4; pp. 425 - 433
• Main Authors: Gorny, Adrienne M, Hay, Frank S, Pethybridge, Sarah J
• Format: Journal Article
• Language: English
• Published: Leiden|Boston Brill 01.04.2021; Brill Academic Publishers, Inc
• Subjects: Bioassays; Cultivars; Galling; Greenhouses; Meloidogyne hapla; Nematicides; Nematodes; Populations; Potatoes; Sampling; Soils; Vegetables; New York; United States > US
• ISSN: 1388-5545; 1568-5411
• DOI: 10.1163/15685411-bja10050

Summary In New York and the Northeastern USA, the northern root-knot nematode, Meloidogyne hapla, is an important soil-borne pathogen of potato. The economic threshold for M. hapla in potato production has been 100 second-stage juveniles (J2) (100 g soil)−1, and is often used to dictate the need for prophylactic nematicides. However, the response of newer, popular potato cultivars under field conditions to M. hapla is unknown. The relationships between initial and final M. hapla populations and potato yield components in the popular cultivars ‘Genesee’, ‘Eva’ and ‘Lamoka’ were evaluated in three commercial production fields in New York, in 2016 and 2017. Following manual extraction from soil samples, M. hapla populations were quantified. Additionally, a glasshouse bioassay was performed to estimate M. hapla populations and correlate tuber yield. Populations of M. hapla over both years ranged from 0 to 519 J2 (100 g soil)−1 at the initial sampling, and from 0 to 10 294 J2 (100 g soil)−1 at the final sampling time. No significant correlation was observed between initial M. hapla populations and tuber yield, or between bioassay plant galling severity and tuber yield, among the cultivars included in the study in either year of the study. Yet correlations between bioassay plant galling severity and M. hapla populations were significant in both years, indicating the bioassay was adept at estimating M. hapla populations. These results will aid in directing future investigations into tolerance to M. hapla and nematode management.