Reproduction, Penetration, and Pathogenicity of Pratylenchus penetrans on Tobacco, Vegetables, and Cover Crops

Abstract

Thirteen cover or forage crops, 14 vegetable crops, eight sativum), and pumpkin (Cucurbita pepo) roots also contomato (Lycopersicon esculentum) cultivars, and four tained large populations of P. penetrans, but none was found tobacco (Nicotiana tabacum) cultivars were examined in the in asparagus (Asparagus officinalis) roots. Differences in greenhouse for susceptibility to root penetration by root populations of P. penetrans occurred within cultivars of Pratylenchuspenetrans. Of the cover and forage crops tested, several crops. Neither root necrosis nor plant height, both Saranac alfalfa (Medicago sativa) and alsike clover indicators of damage by P. penetrans, were consistently (Trifolium hybridum) had the largest populations of P. correlated with P. penetrans populations within the roots. penetrans per total root mass, while timothy (Phleum Knowledge of a plant's interaction with P. penetrans may pratense) and reed canary grass (Phalaris arundinacea) had enable the management of P. penetrans populations in the the smallest. Cucumber (Cucumis sativus), pea (Pisum field by proper selection of crop plants.

Effects of Cover Crops on Pratylenchus penetrans and the Nematode Community in Carrot Production

“…Pratylenchus penetrans is very common in Midwest soils and can reduce yield and value of carrots due to symptoms such as stunting, galling, and root forking (Olthof and Potter, 1973;Vrain and Belair, 1982;Berney and Bird, 1992). Selecting cover crops to manage P. penetrans is difficult as it has a very wide host range which includes oats, radish, and oilseed rape (Miller, 1978;Belair et al, 2002) although susceptibility is known to vary by cultivar (Townshend, 1989;Webb, 1996). In this study, P. penetrans was unaffected by the cover crops tested at Site 1, but its population densities were increased compared to fallow by 'Defender' radish at Site 2 where P. penetrans population densities were numerically greater than at Site 1.…”

“…nematodes do not reproduce well on 'Defender' radish and it can be beneficial for control of these nematodes (Hafez and Sundararaj, 2009;Teklu et al, 2014). However, based on this study and others (Miller, 1978;Belair et al, 2002), radish is a host for Pratylenchus and may increase its population densities. Other cover crops that are compatible with Midwest carrot production and can contribute to lesion nematode management, such as sorghum, sorghum-sudangrass, or rye, which have been beneficial in vegetable systems in the Northeastern United States (Abawi and Widmer, 2000;Everts et al, 2000), could be the focus of future research.…”

Crop Rotation with Tagetes sp. is an Alternative to Chemical Fumigation for Control of Root‐Lesion Nematodes

“…T he root‐lesion nematode ( Pratylenchus penetrans Cobb) is the most important plant‐parasitic nematode in Ontario (Corbett, 1973; Potter and Olthof, 1993) and is known to invade and feed on the roots of many crops and native plants. Significant economic losses to growers due to this feeding injury have been shown on tomato (Reynolds et al, 1992); potato (Olthof, 1987); beet, lettuce, and spinach (Potter and Olthof, 1974); sweet corn (Yu and Potter, 1998); and flue‐cured tobacco (Olthof et al, 1973; Miller, 1978; Johnson et al, 1982; Ball‐Coelho, 1997). Chemical fumigation has been, and is still, the principal means of controlling nematodes in Ontario, particularly for high‐value crops.…”

Difference in lesion formation by male and female Pratylenchus penetrans

“…Lesion appearance was gender-specific and similar for all the three hosts, though symptom progression was slower for dill. Host differences in lesion development have been documented by others in vitro ( Townshend and Stobbs, 1981 ) as well as in planta ( Miller, 1978 ). Contrary to pea and alfalfa, the host status of dill for P. penetrans is not well known except that Miller (1978) documented severe necrosis on dill compared to other hosts.…”