The Root-Lesion Nematode, , Affects Early Growth and Physiology of Grafted M.9, G.41, and G.935 Apple Rootstocks Similarly Under Field Microplot Conditions.

The root-lesion nematode, , is a ubiquitous parasite of roots of temperate fruit trees. It affects early growth of trees replanted into former orchard sites where populations have built up and may contribute to decline complexes of older trees. Most British Columbia, Canada, apple acreage is planted with M.

Potential impacts of the ring nematode, , on grapevines in British Columbia: a microplot study.

The Okanagan Valley of British Columbia hosts a wine grape industry that has grown substantially in the past three decades in terms of both acreage and economic benefit to the region. The ring nematode, , has recently been found to be widespread in vineyard soils in the region. This study used field microplots to assess the potential impacts of a local population of on the first four years growth of either self-rooted 'Merlot' or 'Merlot' vines grafted onto three commonly used rootstocks: 3309C, 44-53M, and Riparia Gloire.

Influences of nitrogen inputs on nematode populations under highbush blueberry.

This study examined the effects of nitrogen fertilization on populations of , , and , and indices of free-living nematode community structure, in relation to highbush blueberry production in British Columbia, Canada. The field experiment was established in fall of 2008 with six replicate plots of each of four experimental N fertilization treatments: 0, 100, 150, and 200% of the annual application rate recommended for conventional blueberry production in the region. Nematode populations were quantified annually from 2009 through 2015, and then nematode populations and root biomass were quantified at seven sample dates from 2016 through 2019.

Dynamics of the impacts of on Gisela® cherry rootstocks.

Sweet cherry growers are increasingly using semi-dwarfing rootstocks, including the Gisela® series, when replanting orchards. Little is known of the susceptibility of these new cherry rootstocks to , a recognized pest of temperate fruit trees worldwide. Two field experiments were planted in 2010, one in the Okanagan Valley of British Columbia and one in the Annapolis Valley of Nova Scotia.

Pseudomonads contribute to regulation of Pratylenchus penetrans (Nematoda) populations on apple.

Inoculation with antagonistic soil microorganisms has shown potential to suppress replant disease of apple in orchard soils. Pseudomonas spp. may have the potential to reduce Pratylenchus penetrans populations on apple.

Seasonality and breeding success of captive and wild Tasmanian devils (Sarcophilus harrisii).

The synchrony and timing of reproductive events are crucially important factors to maximize individual and offspring survival, especially in seasonal environments. To increase our understanding of the physiological basis of seasonality and the influence of associated environmental factors (maximum temperature, day length and rate of day length change associated with different latitudes) on reproduction in Tasmanian devils, we reviewed records and research data from captive facilities throughout Australia in comparison to those from a wild population study (1974-1987). Overall, breeding activity began 2 weeks earlier in the captive than the wild population (week 5.

Using C. elegans Forward and Reverse Genetics to Identify New Compounds with Anthelmintic Activity.

Background: The lack of new anthelmintic agents is of growing concern because it affects human health and our food supply, as both livestock and plants are affected. Two principal factors contribute to this problem. First, nematode resistance to anthelmintic drugs is increasing worldwide and second, many effective nematicides pose environmental hazards.

Soil Aggregate Dynamics and Plant Community Response after Biosolids Application in a Semiarid Grassland.

Biosolids may improve the ecological function of degraded semiarid grasslands, but an understanding of the plant community is essential. An experiment was established in 2001 to determine the effects of a single surface application of biosolids on soil aggregate stability and the composition of the plant community in a semiarid grassland in British Columbia, Canada. Four treatments were evaluated: (i) surface biosolids application at 20 (Bio-20) and (ii) 60 Mg ha (Bio-60), (iii) mineral fertilizer, and (iv) a control.

Characterization of antibiotic-resistant and potentially pathogenic Escherichia coli from soil fertilized with litter of broiler chickens fed antimicrobial-supplemented diets.

The objective of this study was to characterize antimicrobial resistance and virulence determinants of Escherichia coli from soil amended with litter from 36-day-old broiler chickens ( Gallus gallus domesticus ) fed with diets supplemented with a variety of antimicrobial agents. Soil samples were collected from plots before and periodically after litter application in August to measure E. coli numbers.

Precision placement of separated dairy sludge improves early phosphorus nutrition and growth in corn ( L.).

Efficient use of manure nutrients by crops is necessary to minimize losses to the environment. This field study examined the possibility of replacing side-banded mineral P with precision-placed high-P sludge (6.2-11.

Biosolids increase soil aggregation and protection of soil carbon five years after application on a crested wheatgrass pasture.

Biosolids application to rangelands and pastures recycles nutrients and organic matter back to soils. The effects of biosolids (20 and 60 dry Mg ha(-)(1)) and N+P fertilizer on soil aggregate stability, bulk density, aeration porosity, and total C and N of stable aggregates were evaluated 4 and 5 yr after surface application to a crested wheatgrass [Agropyron cristatum (L.) Gaertn.

Agronomic effects of multi-year surface-banding of dairy slurry on grass.

Sleigh-foot application of slurry manure is the best method for applying slurry manure on many forage fields. This study was designed to assess agronomic effectiveness of multi-year surface banding of dairy slurry on a sward of tall fescue (Festuca arundinacea Schreb.).

Impacts of Sustained Use of Dairy Manure Slurry and Fertilizers on Populations of Pratylenchus penetrans under Tall Fescue.

Various manures and composts have been reported to reduce population densities of plant-parasitic nematodes. Dairy manure slurry is often used as a primary source of nitrogen for forage crops. This study was conducted to determine the effects of dairy manure on population densities of Pratylenchus penetrans parasitizing tall fescue.

Pseudomonas chlororaphis Strain Sm3, Bacterial Antagonist of Pratylenchus penetrans.

The interaction of Pseudomonas chlororaphis strain Sm3 and the root-lesion nematode Pratylenchus penetrans was investigated in three separate greenhouse experiments with soils from southern British Columbia, Canada. The bacteria were applied to the roots of strawberry plants and planted in unpasteurized field soils, with natural or supplemented infestation of P. penetrans.

Population Growth of Pratylenchus penetrans on Winter Cover Crops Grown in the Pacific Northwest.

Population growth of Pratylenchus penetrans on 13 fall and winter cover crops was studied in the greenhouse and field. All crops except oat cv. Saia supported population growth of P.

Plant-Parasitic Nematodes Associated with Grapevines, Vitis vinifera, in Oregon Vineyards.

A survey of vineyards in western Oregon was conducted in 1994 and 1995 to determine the association of plant-parasitic nematodes with vine health. Seventy vineyards in four regions of western Oregon (16 to 21 vineyards per region) were sampled. The regions were the northern, middle, and southern Willamette Valley, and southern Oregon.

Temporal Changes in the Vertical Distribution of Pratylenchus penetrans under Raspberry.

Population densities of Pratylenchus penetrans and the biomass of fine roots of raspberry at depths of 0-5, 5-10, 10-20, and 20-30 cm were determined every 2 weeks for 2 years. The vertical distribution of P. penetrans varied from season to season, but the seasonal changes were not similar for the 2 years.

Impact of Thermal History on Tolerance of Meloidogyne hapla Second-stage Juveniles to External Freezing.

Low temperature induced physiological changes that increased the ability of second-stage juveniles of Meloidogyne hapla to survive external freezing. Second-stage juveniles in polyethylene glycol solution were exposed to -4 , 0, 4, or 24 C, and then their survival was determined after ice-induced freezing of the suspensions at - 4 C for 24 hours. Survival was greatest for juveniles exposed to 4 C before freezing.

Winter Survival of Pratylenchus scribneri.

Population densities of Pratylenchus scribneri in a Plainfield loamy sand soil were sampled from 1 October to 1 May for 4 years. From May to October of each year, the site was planted to Russet Burbank potato and Wis 4763 corn. Percentages of change in population densities of nematodes were computed on the basis of number of nematodes present on 1 October.

Cold Hardening of Meloidogyne hapla Second-stage Juveniles.

The effect of previous exposure to low temperatures on freezing tolerance was determined for second-stage juveniles of Meloidogyne hapla. Juveniles in 5% polyethylene glycol 20,000 were exposed to 0-24 C for 12-96 hours, and then freezing tolerance was assessed by freezing samples at -4 C for 24 hours, thawing, and determining survival. Freezing tolerance was inversely related to prefreeze temperatures of 4-24 C.

Nematode autofluorescence and its use as an indicator of viability.

Representatives of 15 nematode genera were viewed with 450-490-nm epi-illumination and found to autofluoresce. The autofluorescence was limited to 1-5-mum-d globules in the intestinal cells of live nematodes. When adult Pratylenchus penetrans or Caenorhabditis elegans were killed with formaldehyde, freezing, or heat, autofluorescence dispersed throughout the body.