Pratylenchus penetrans and P. neglectus in tubers of potato (Solanum tuberosum) in Ontario

1991 ◽  
Vol 71 (4) ◽  
pp. 1251-1256 ◽  
Author(s):  
Th. H. A. Olthof ◽  
M. S. Wolynetz

Root-lesion nematodes (Pratylenchus penetrans) were extracted from peels of potato tubers (Solanum tuberosum 'Russet Burbank'). The average number of P. penetrans recovered over a 2-wk period in a mist chamber from four batches of tubers, stored for 3–18 wk at 7 °C in a cold room, ranged from 11 to 1925 nematodes tuber−1. An average of 374 Pratylenchus neglectus tuber−1 were recovered from the peels of potato Norchip, grown in soil containing on average 4370 nematodes kg−1 of soil at harvest, and stored for 19 wk at 7 °C. P. penetrans and P. neglectus were recovered only from the outer layer of potato tubers; none was found in the inner core. Planting halves of tubers containing an average of 1925 P. penetrans tuber−1 into nematode-free soil resulted in soil population densities of 2225 P. penetrans kg−1 of soil and root population densities of 884 nematodes root system−1 after 8 wk in the greenhouse. Although many, if not most, potato fields in southern Ontario are already infested by P. penetrans, these studies have shown that stored, infested tubers can initiate a new infestation. Key words: Peel, potato tuber, Pratylenchus neglectus, Pratylenchus penetrans, root-lesion nematode, Solanum tuberosum

1989 ◽  
Vol 69 (3) ◽  
pp. 903-905 ◽  
Author(s):  
J. L. TOWNSHEND

The population densities of four species of root-lesion nematodes (Pratylenchus) were examined in two cultivars of oat (Avena sativa L.) grown in greenhouse pots. The cultivar Saia harbored fewer P. neglectus and P. penetrans than the cultivar OAC Woodstock, while both cultivars were similar hosts for P. sensillatus. Pratylenchus crenatus did not develop in either cultivar.Key words: Oat, population density, Pratylenchus crenatus, Pratylenchus neglectus, Pratylenchus penetrans, Pratylenchus sensillatus


1991 ◽  
Vol 71 (4) ◽  
pp. 1243-1250 ◽  
Author(s):  
Th. H. A. Olthof ◽  
J. L. Townshend ◽  
M. S. Wolynetz

Soaking potato (Solanum tuberosum 'Russet Burbank') tuber halves for 1 h in sodium hypochlorite (1% available chlorine) or for 20 min in a 32 mg mL−1 solution of oxamyl (24% liquid) reduced the number of root-lesion nematodes (Pratylenchus penetrans) in the peel by 92 and 88%, respectively, relative to untreated tuber halves extracted in a mist chamber for 2 wk. Treated tuber halves were grown in pots for 8 wk in the greenhouse. There was no phytotoxicity in the plants that emerged although sodium hypochlorite may have inhibited plant emergence; both treatments reduced the number of days required for plant emergence by 3–6 d. In general, both chemicals increased plant growth. Oxamyl was completely effective in preventing a nematode infestation of the soil; sodium hypochlorite was ineffective. On average, only a single specimen of P. penetrans was recovered from the oxamyl-treated root system vs. 835 in the sodium hypochlorite treatment. No P. penetrans was recovered from the oxamyl-treated original seed-piece after 8 wk whereas an average of 427 and 329 half-tuber−1 were present in those treated with water or sodium hypochlorite, respectively. The data suggest that a 20-min immersion of P. penetrans-infested potato seed pieces in oxamyl is extremely effective in preventing soil infestation by the nematode. Key words: Bleach, disinfection, potato, Pratylenchus penetrans, root-lesion nematode, Solanum tuberosum


2005 ◽  
Vol 80 (3) ◽  
pp. 179-184 ◽  
Author(s):  
J. Kimpinski ◽  
Y.A. Papadopoulos ◽  
B.R. Christie ◽  
K.B. McRae ◽  
C.E. Gallant

Greenhouse trials were conducted to determine the levels of invasion of birdsfoot trefoil(Lotus corniculatus) cultivars and lines by the root-lesion nematode (Pratylenchuspenetrans). Numbersof nematodesin roots grown in 50-cm3 polystyrene starter pots were determined 6 weeks after planting. Nematodes were detected in the roots of all cultivars and lines, though the degree of invasion varied significantly. In the first screening trial, carried out in 1994 on 23 cultivars and lines, NB90-104, Upstart, and Viking harbored the lowest population densities of nematodes with levels below 1 000 g-1 of dry root, while Fergus and EPF had population densities over 30 000 g-1 of dry root. In the second screening trial conducted in 1995, all nine cultivars and lines tested, including NB90-104, Upstart, and Viking, had nematode levels greater than 7 900 g-1 of dry root. The results indicated that the cultivars and lines tested in this study exhibited wide genetic variability for invasion by root-lesion nematodes.


1989 ◽  
Vol 69 (2) ◽  
pp. 611-615 ◽  
Author(s):  
J. KIMPINSKI ◽  
J. B. SANDERSON

In a 3-yr field study at Upton, Prince Edward Island, aldicarb at 1.12 and 2.24 kg a.i. ha−1 and oxamyl at 2.24 kg a.i. ha−1 were applied in the furrow with seed potatoes. Nematicide treatments increased tuber yields of Superior by 15.5% (4.6 t ha−1) and yields of Russet Burbank by 9.3% (3.4 t ha−1). Shepody did not respond to nematicide treatments. The effect of aldicarb on average yields of all three cultivars did not differ from that of oxamyl, nor did yields at the higher rate of aldicarb differ from those at the lower rate. In a two-year field study at Harrington, Prince Edward Island, aldicarb and aldoxycarb applied at a rate of 2.24 kg a.i. ha−1 increased yields of Superior by similar amounts of about 40% (9.4 t ha−1). Oxamyl applied at the same rate in the second year had the same impact on yields as aldicarb or aldoxycarb. Nematicide treatments reduced the numbers of root lesion nematodes (primarily Pratylenchus penetrans) in roots and soil at Upton. Both rates of aldicarb had a similar impact, but oxamyl was less effective than the aldicarb treatments in reducing nematode numbers in roots. At Harrington, aldicarb controlled nematode populations more efficiently than aldoxycarb in soil in the first year and in roots in the second year. Aldoxycarb and oxamyl reduced nematode populations to a similar degree.Key words: Aldicarb, aldoxycarb, oxamyl, Pratylenchus penetrans, Solanum tuberosum


HortScience ◽  
1990 ◽  
Vol 25 (3) ◽  
pp. 318-320
Author(s):  
J.L. Townshend

The effects of temperature and root-lesion nematodes [Pratylenchus penetrans (Cobb)] on the growth of newly germinated `Bartlett' pear seedlings (Pyrus communis L.) were examined. At five temperatures from 10 to 30C, P. penetrans (five per gram of soil) did not purple the leaves. After 8 weeks, leaf number, trunk height, and top and root weights were reduced only at 25C. The number of P. penetrans in the roots were greatest at 15 and 20C. At 20C, P. penetrans (16 per gram of soil) caused the leaves of seedlings to turn purple, and, by 6 weeks after treatment, the nematodes had reduced leaf production, trunk elongation, and top and root growth.


2021 ◽  
pp. 362-367
Author(s):  
Ann E. MacGuidwin

Abstract Pratylenchus penetrans is a cosmopolitan species reported from 69 countries representing every continent except Antarctica. P. penetrans has a wide host range including potato and is found throughout the potato growing region of the northern USA. Most potato fields are infested with the fungus Verticillium dahliae as well as root lesion nematodes, and a disease interaction between the two has been demonstrated for multiple soil types, potato cultivars and production regions. The significance of the interaction between P. penetrans and V. dahliae is that it is synergistic rather than additive. This chapter discusses the economic importance, distribution, symptoms of damage, biology and life cycle, recommended integrated nematode management and management optimization of P. penetrans. Future research requirements are also mentioned.


1964 ◽  
Vol 44 (3) ◽  
pp. 272-275 ◽  
Author(s):  
G. T. Morgan ◽  
W. B. Collins

As a source of organic material in strawberry culture, composted timothy hay resulted in the greatest depression of soil populations of root lesion nematodes, Pratylenchus penetrans (Cobb. 1917) Filip & Stek., 1941. In contrast, actively growing timothy sod caused the largest increase in soil nematodes.In a crop rotation, timothy also resulted in high populations of P. penetrans while beans lowered the numbers appreciably.


HortScience ◽  
1994 ◽  
Vol 29 (9) ◽  
pp. 1074-1077 ◽  
Author(s):  
John W. Potter ◽  
Adam Dale

Intraspecific crossing of `Guardian' and `Midway' cultivated strawberry (Fragaria ×ananassa Duch.) produced a family of genotypes, some of which suppressed root-lesion nematode [Pratylenchus penetrans (Cobb)] population counts and produced large berries and high yield. Unlike `Midway', `Guardian' also suppressed P. penetrans. Among several beach strawberry [Fragaria chiloensis (L.) Duch.] and woodland strawberry (Fragaria virginiana Duch.) genotypes, variation was found in resistance and tolerance to root-lesion nematodes. Three F. chiloensis genotypes showed tolerance, and at least two genotypes may be somewhat resistant. Three F. virginiana genotypes also were tolerant, and three were resistant. Also, one (`Little Cataraqui 4') combined root growth vigor with nematode resistance. We concluded that exploitable genetic diversity in vigor and reaction to root-lesion nematodes exists in wild Fragaria and in F. ×ananassa.


2014 ◽  
Vol 15 (3) ◽  
pp. 112-117 ◽  
Author(s):  
T. C. Todd ◽  
J. A. Appel ◽  
J. Vogel ◽  
N. A. Tisserat

Observations on the prevalence and abundance of plant-parasitic nematodes were made from soil and root samples collected from 2,640 wheat fields in Kansas and Colorado during 2007-2010. Stunt nematodes (predominately Merlinius brevidens and Quinisulcius acutus), root-lesion nematodes (predominately Pratylenchus neglectus), and pin nematodes (Paratylenchus projectus) were the most commonly encountered taxa. Maximum soil population densities of 6,520 and 1,880 nematodes/100 cm3 soil were observed for pin and stunt nematodes, respectively, while a maximum root population density of 90,309 nematodes/g dry root was observed for root-lesion nematodes. Lower nematode densities were associated with wheat following corn, grain sorghum, or soybean for pin and stunt nematodes, and with wheat following fallow for root-lesion nematodes. Based on the results of this survey, 6% and 8% of wheat acreage in the central Great Plains are estimated to be at risk for significant (>5%) yield loss due to stunt nematodes and root-lesion nematodes, respectively. The number of fields with high population densities of both stunt and root-lesion nematodes was negligible (1%); therefore, the total wheat acreage with nematode populations above provisional economic thresholds is estimated to be ∼13%. Damage relationships with greater accuracy, precision, and relevance are necessary to establish reliable yield loss estimates for this region. 3 June 2014. 11 August 2014.


Sign in / Sign up

Export Citation Format

Share Document