Progress 10/01/15 to 09/30/16
Outputs
Target Audience: The primary target for this research is growers who are experiencing losses from plant-parasitic nematodes. Additional targets include extension personnel, crop advisors and others. Efforts included outreach at the WVU Organic Research Farm Field Day, Aug. 27, 2016 with workshops attended by approximately 120 individuals. Additional outreach included orchard growers as part of a nematode survey in 2016. Changes/Problems:We discovered that the formulation of Bacillus firmus obtained from a commercial supplier and used in lab trials was actually a mixture of Bacillus firmus and Bacillus cereus. Genome analyses indicated they were 97 % homologous, and trials to compare efficacy of the two strains demonstrated that they had similar effects on root know nematode. What opportunities for training and professional development has the project provided?A graduate student has conducted research to evaluate the effects of Bacillus firmus on dagger and root lesion nematodes. One undergraduate repeated the experiments as an Independent Study project, while two other undergraduate students assisted with nematode population assays. How have the results been disseminated to communities of interest?We prepared a workshop at the WVU Organic Farm Field Day to discuss parasitic nematodes. Nematicide recommendations were revised based on results of the field trials and were presented in regional Commercial Tree Fruit production guides. What do you plan to do during the next reporting period to accomplish the goals?Population density and activity of nematode biocontrol agents will continue to be monitored in organic farming systems. Soils will be assayed to determine whether suppressiveness is biologically mediated and can be re-established in sterilized soils. Farming systems research will evaluate the effects of compost amendments and rotations in organic vegetable and field crop production systems on nematode community structure. Soil suppressiveness to nematodes and population dynamics of indigenous biocontrol agents will be compared with emphasis on isolating biological controls for root knot and root lesion nematodes. A new trial will be initiated to evaluate cultivars for tolerance and resistance to root knot nematodes.
Impacts
What was accomplished under these goals?
Objective 1. Develop effective and economically viable cultural management tactics for plant-parasitic nematodes based on host resistance, nematode-antagonistic rotation or cover crops, soil amendments and biological agents. Effects of Rotations and Manure Compost on Nematode Communities in Organic Farming Systems A large farming systems trial, begun in 1999 to evaluate transition methods for conversion from conventional to organic farming practices, was continued through 2016. A vegetable crop trial evaluated a high input, compost intensive management system versus a low-input system that relies on green manures and cover crops. High input treatments received 10 tons/acre of composted dairy manure annually and were planted to one of four vegetable families in rotation: legumes (beans and peas), Solanaceae (pepper and tomato), cucurbits (squash and pumpkin), and leafy vegetables (lettuce and spinach). Hairy vetch, cowpea and buckwheat were planted as cover crops to boost soil fertility and organic matter content. The treatments were repeated with a field crop trial where the high input plots were planted to wheat, soybean, corn, or forage rape. The field crop treatments were also factored into plots with or without animal grazing (sheep) beginning in 2001. Soil samples were collected preplant and late season in each year and were analyzed for plant-parasitic and predatory nematodes, and assayed for nematode biocontrol agent activity. Common nematodes found include Pratylenchus crenatus, Xiphinema rivesi, Helicotylenchus spp., Hoplolaimus spp. Meloidogyne hapla, and Clarkus papillatus (predator). Population densities remained low for all plant parasites throughout the 16 years of this experiment and few differences among compost treatments or crops were statistically significant. Novel Nematode Management Options in Peach Orchards Two trials comparing five nematicide treatments in peach orchards were initiated in 2014 and continued in 2015 and 2016. At the Kearneysville Fruit Tree Research and Education Center in Jefferson County, WV, plots consisted of three 12-year-old trees of cv Bounty on Halford rootstocks. All products are commercially available for nematode control on peach, but have very little information regarding efficacy on nematodes problematic in Mid-Atlantic peach orchards (Xiphinema, Mesocriconemella, and Pratylenchus). Treatments were applied May 8, 2014 and May 13, 2015 (about 1 week after petal fall). Movento (spirotetramet) was applied to foliage in 1000 Gal water/acre with an airblast sprayer at 0.63 Kg/Ha (9oz/A). Other materials were applied to the herbicide strip beneath trees and included: 1) DiTera (Myrothecium verrucaria) granules at 117 kg/Ha (104 lb/A); 2) Ecozin Plus-Spring (azadirachtin) at 2.1 kg/Ha (1.875 lb/A), applications were repeated 2 and 4 weeks later; 3) Ecozin Plus-Spring & Fall. as above, with applications repeated in Fall; and 4) Nema-Q (Quillaria saponaria, Soapwood extract) at 14 L/Ha (1.5 Gal/A). All plots, including untreated controls were sprayed with tap water at 1000 gal/acre (~0.1 cm) to incorporate the materials, later applications relied on rainfall. Soil samples were collected for nematode assay, and trunk diameters were measured, on May 8 (pre-treatment) and again on June 19 and Oct. 7, 2014. In 2015, soil samples were collected May 13, July 28, and Oct. and Nov. 7. A final set of samples and trunk diameter measurements were collected June 29, 2016 A second site was established in Hampshire County, WV at a commercial orchard exhibiting losses to stem pitting. Plots consisted of twelve 5-year-old peach trees (cv. Contender on Bailey rootstock). Treatments were applied to soil on May 14, 29014, and repeated on May 16, 2015 and included 1) Ditera, 2) Ecozin (Spring only), and 3) Nema-Q at the same rates as above. The Ecozin treatment was repeated on May 28, 2014, and on May 31 and June 14, 2015. Soil samples and trunk diameters were collected on May 14 and again on Oct 7, 2014, and on July 28 and Nov. 7 2015. Final measurements were collected June 29, 2016. Xiphinema rivesi was the dominant dagger nematode at the Kearneysville site whereas the Hampshire County site was dominated by Xiphinema americanum. Nematode populations did not differ significantly from controls in either year, nor did tree growth or survival differ significantly among nematicide treatments. The sprayer irrigation and reliance on natural rainfall may have been insufficient for adequate incorporation of these products. Mode of action of Bacillus firmus for nematode biocontrol Laboratory and greenhouse trials evaluated the bacterium Bacillus firmus for control of dagger nematode, Xiphinema americanum, and root knot nematode, Meloidogyne hapla, and to determine the mode of action. Genomic analyses determined that the formulation obtained from the manufacturer was a mixture of Bacillus firmus and B. cereus, however, no differences in efficacy were observed among these strains. Direct toxicity to either nematode occurred only at extremely high bacterial densities (10E7 cfu/ml), nor was egg production per female affected by B. cereus or B. firmus with M. hapla. An attraction assay demonstrated that M. hapla juveniles were attracted to a soil extract, but not to either Bacillus spp. in vitro. Roots of tomato dipped in a suspension of either B. firmus or B. cereus attracted significantly fewer M. hapla than roots dipped in a soil extract control. However, B. cereus had no significant effect on attraction of Xiphinema americanum. Objective 2. Evaluate cultural management procedures for plant-parasitic nematodes in relation to their impacts on the sustainability of soil health: With special reference to the utility of nematode community structure as an indicator of overall soil quality and their roles in plant nutrient cycling. No new progress. Objective 3. Provide educational materials and programs on cultural management of plant-parasitic nematodes and sustainable soil health systems as a component of on-going extension and outreach efforts. No new progress.
Publications
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2016
Citation:
Valencia, L. 2016. Bacillus firmus for the biological control of Meloidogyne hapla and Xiphinema americanum. MS. Thesis. West Virginia University. Morgantown, WV. 62. P.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Kotcon, J. 2016. Efficacy of Reduced-Impact Nematicides for Management of Dagger Nematode in Peach. J. Nematoloogy 48:340.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Valencia, L. and J. B. Kotcon. 2016. Efficacy and mode of action of Bacillus firmus as a bionematicide for the northern root-knot nematode, Meloidogyne hapla and dagger nematode, Xiphinema americanum. Journal of Nematology 48:370-379.
|
Progress 10/01/09 to 09/30/16
Outputs
Target Audience:Organic fruit and vegetable growers in West Virginia, and conventional tree fruit producers were the primary targets of research and outreach efforts. Additional contacts include Extension agents and crop advisors, and the WVMaster Gardener program. Changes/Problems:We discovered that the formulation of Bacillus firmus obtained from a commercial supplier and used in lab trials was actually a mixture of Bacillus firmus and Bacillus cereus. Genome analyses indicated they were 97 % homologous, and trials to compare efficacy of the two strains demonstrated that they had similar effects on root know nematode. What opportunities for training and professional development has the project provided?Two graduate students completed Masters theeis in support of this project. Six undergraduate studentshave participated in greenhouse and laboratory trials during this period. James Kotcon attended the Society of Nematologists meetings and the annualNE-1040 Nematology Regional research technical committee meetings each year except 2014. How have the results been disseminated to communities of interest?We prepared a workshop at the WVU Organic Farm Field Day to discuss parasitic nematodes. Nematicide recommendations were revised based on results of the field trials and were presented in regional Commercial Tree Fruit production guides. What do you plan to do during the next reporting period to accomplish the goals?This project has been re-written and approved for 2016-2021 as NE-1640.
Impacts
What was accomplished under these goals?
A large farming systems trial, begun in 1999 to evaluate transition methods for conversion from conventional to organic farming practices, was continued through 2013. A vegetable crop trial evaluated a high input, compost intensive management system versus a low-input system that relies on green manures and cover crops. High input treatments received 10 tons/acre of composted dairy manure annually and were planted to one of four vegetable families in rotation: legumes (beans and peas), Solanaceae (pepper and tomato), cucurbits (squash and pumpkin), and leafy vegetables (lettuce and spinach). Hairy vetch, cowpea and buckwheat were planted as cover crops in in 2011 and 2012. The treatments were repeated with a field crop trial where the high input plots were planted to wheat, soybean, corn, or forage rape. The field crop treatments were also factored into plots with or without animal grazing (sheep) beginning in 2001.Soil samples were collected preplant and late season in each year and were analyzed for plant-parasitic and predatory nematodes, and assayed for nematode biocontrol agent activity. Common nematodes found include Pratylenchus crenatus, Xiphinema rivesi, Helicotylenchus spp., Hoplolaimus spp. Meloidogyne hapla, and Clarkus papillatus (predator). Population densities remained low for all plant parasites throughout the 14 years of this experiment and few differences among compost treatments or crops were statistically significant. Rotation and Cover Crop Evaluations A trial comparing five summer cover crops was initiated in 2013 as part of the vegetable farming systems trial described above. High input plots received 10 tons per acre of dairy manure compost as a soil fertility amendment, and were planted to buckwheat as a summer cover crop. Four replicate plots each in the low input (no compost) treatment were planted to four legume cover crops (soybean, cowpea, sunn hemp, and sesbania) to build soil fertility. Population densities of lesion, spiral, and Mononchus nematodes were highest on sesbania, while dagger nematode populations were lowest on sesbania and greatest on sunn hemp. Differences among crops were not statistically significant. A field trial was initiated to evaluate Sunn Hemp (Crotalaria juncea) as a cover crop for nematode and weed suppression in vegetable and orchard sites. Initial samples showed no differences among treatments. Five cultivars of switchgrass were planted in 1X1m plots with or without 10 T/A dairy manure compost in 2008 to assess the role of nematodes. Little growth was seen in 2009 or 2010, but switchgrass dominated the plots in 2011. Yields of orchard grass yields were lowest, with Atlantic,Performer and Cave-In-Rock yielding less than Big Bluestem, Shawnee or Alamo. Compost did not affect yields. Population density of Pratylenchus, Xiphinema, and Mononchus did not differ among treatments, but Helicotylenchus populations were lower on Big Bluestem and Performer than on Kanlow, Atlantic, or orchard grass. Total biomass was negatively correlated with population density of Helicotylenchus. Effects of Soil Amendments with Neem Oil on Plant Parasitic Nematodes The mode of action of Neem products for suppression of Meloidogyne incognita and M. hapla in tomato was evaluated in laboratory trials. We tested whether Neem affects motility, host finding ability, and life cycle of root-knot nematodes. Three layers of soil were placed in 250-cm3 pots. The bottom layer contained 50 cm3 of steamed soil. Nematode inoculum (2,500 M. incognita or M. hapla eggs per pot) was pipetted onto the bottom layer. The middle layer contained 50 cm3 soil with three treatments: control, soil layer, and drench. The soil layer and drench treatments both contained Neem oil at label rates (0.2 g/kg steamed soil). The middle soil layer of controls was without Neem oil. Wire mesh was placed over the middle soil layer, and 150 cm3 steamed soil was added as a top layer. Tomato seedlings were transplanted into the steamed soil in the top layer. The drench treatment received weekly Neem drenches (0.016g Neem oil in 10 ml water). After 10, 20, and 40 days, roots of three replicates of each treatment were harvested separately from above and below the screen, bleached and stained. The effect of Neem on nematode movement was assessed by counting nematodes in upper and lower portions of the root systems. Neem suppressed gall number in tomato roots inoculated with M. incognita, especially at 40 days after inoculation, but not roots inoculated with M. hapla. Neem also suppressed plant dry weight in this trial. Novel Nematode Management Options in Peach Orchards Two trials comparing five nematicide treatments in peach orchards were initiated in 2014 and continued in 2015 and 2016. Plots in Jefferson County, WV consisted of three 12-year-old trees of cv Bounty on Halford rootstocks. All products are commercially available for nematode control on peach, but have very little information regarding efficacy on nematodes problematic in Mid-Atlantic peach orchards (Xiphinema, Mesocriconemella, and Pratylenchus). Treatments were applied about 1 week after petal fall in 2014, and repeated in 2015 as per label directions. Movento (spirotetramet) was applied as a foliar spray. Materials applied to the herbicide strip beneath trees included: 1) DiTera (Myrothecium verrucaria) granules; 2) Ecozin Plus-Spring (azadirachtin), applications were repeated 2 and 4 weeks later; 3) Ecozin Plus-Spring & Fall. as above, with applications repeated in Fall; and 4) Nema-Q (Quillaria saponaria, Soapwood extract). All plots, including untreated controls were sprayed with tap water at 1000 gal/acre (~0.1 cm) to incorporate the materials, later applications relied on rainfall. Soil samples were collected for nematode assay, and trunk diameters were measured, in spring, mid-season and fall each year. A second trail was established at acommercial orchard exhibiting losses to stem pitting in Hampshire County, WV. Plots consisted of twelve 5-year-old peach trees (cv. Contender on Bailey rootstock). Treatments were applied to soil on May 14, 2014, and repeated on May 16, 2015 and included 1) Ditera, 2) Ecozin (Spring only), and 3) Nema-Q at the same rates as above. The Ecozin treatment was repeated on May 28, 2014, and on May 31 and June 14, 2015. Soil samples and trunk diameters were collected in spring, mid-season and fall each year through June 29, 2016. Xiphinema rivesi was the dominant dagger nematode at the Kearneysville site whereas the Hampshire County site was dominated by Xiphinema americanum. Nematode populations did not differ significantly from controls in either year, nor did tree growth or survival differ significantly among nematicide treatments. The sprayer irrigation and reliance on natural rainfall may have been insufficient for adequate incorporation of these products. Mode of action of Bacillus firmus for nematode biocontrol Laboratory and greenhouse trials evaluated the bacterium Bacillus firmus for control of dagger nematode, Xiphinema americanum, and root knot nematode, Meloidogyne hapla, and to determine the mode of action. Genomic analyses determined that the formulation obtained from the manufacturer was a mixture of Bacillus firmus and B. cereus, however, no differences in efficacy were observed among these strains. Direct toxicity to either nematode occurred only at extremely high bacterial densities (10E7 cfu/ml), nor was egg production per female affected by B. cereus or B. firmus with M. hapla. An attraction assay demonstrated that M. hapla juveniles were attracted to a soil extract, but not to either Bacillus spp. in vitro. Roots of tomato dipped in a suspension of either B. firmus or B. cereus attracted significantly fewer M. hapla than roots dipped in a soil extract control. However, B. cereus had no significant effect on attraction of Xiphinema americanum.
Publications
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2015
Citation:
King, Tiara. 2015. Investigations of Pasteuria and the Root-Lesion Nematode Pratylenchus penetrans in Soils Collected
from Certified Organic Farms in the Mid-Atlantic United States. MS. Thesis. West Virginia University. Morgantown, WV.
85. P.
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2016
Citation:
Valencia, L. 2016. Bacillus firmus for the biological control of Meloidogyne hapla and Xiphinema americanum. MS.
Thesis. West Virginia University. Morgantown, WV. 62. P.
- Type:
Book Chapters
Status:
Published
Year Published:
2010
Citation:
Kotcon, J. B. 2010. Population dynamics of earthworms in organic farming systems. Pp. 299-310. In Karaca, A. (ed.)
Biology of Earthworms. Springer-Verlag. Berlin.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2010
Citation:
King, T. N. and J. B. Kotcon. 2010. Reproduction of Pratylenchus penetrans in soils with and without Pasteuria spp.
Abstract. Presented at Society of Nematologists annual meeting, Boise Idaho.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Kotcon, J. 2016. Efficacy of Reduced-Impact Nematicides for Management of Dagger Nematode in Peach. J. Nematology 48:340.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Valencia, L. and J. B. Kotcon. 2016. Efficacy and mode of action of Bacillus firmus as a bionematicide for the northern
root-knot nematode, Meloidogyne hapla and dagger nematode, Xiphinema americanum. Journal of Nematology 48:370-379.
|
Progress 10/01/14 to 09/30/15
Outputs
Target Audience:The primary target for this research is growers who are experiencing losses from plant-parasitic nematodes. Additional targets include extension personnel, crop advisors and others. Efforts included outreach at the WVU Organic Research Farm Field Day, Aug. 13, 2015 with workshops attended by approximately 80 individuals. Additional outreach included orchard growers as part of a nematode survey in 2015. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?A graduate student has conducted research to evaluate the effects of Bacillus firmus on dagger and root lesion nematodes. How have the results been disseminated to communities of interest?We prepared a workshop at the WVU Organic Farm Field Day to discuss parasitic nematodes. Nematicide recommendations were revised based on results of the field trials and were presented in regional Commercial Tree Fruit production guides. What do you plan to do during the next reporting period to accomplish the goals? Population density and activity of nematode biocontrol agents will continue to be monitored in organic farming systems. Soils will be assayed to determine whether suppressiveness is biologically mediated and can be re-established in sterilized soils. Farming systems research will evaluate the effects of compost amendments and rotations in organic vegetable and field crop production systems on nematode community structure. Soil suppressiveness to nematodes and population dynamics of indigenous biocontrol agents will be compared with emphasis on isolating biological controls for root knot and root lesion nematodes. Research to evaluate the mode of action of a new commercially-available nematode biocontrol agent, Bacillus firmus, will be completed in 2016. Data are being analyzed from trials to evaluate nematode survival when incubated in solutions of B. firmus, as well as to assess nematode attraction to roots, infection and reproduction. Peach nematicide trials will be completed in 2016, with additional efforts to assess effects on non-target biocontrol agents. Tree fruit responses and performance of grower nematode management plans will be assessed.
Impacts
What was accomplished under these goals?
Objective 1. Develop effective and economically viable cultural management tactics for plant-parasitic nematodes based on host resistance, nematode-antagonistic rotation or cover crops, soil amendments and biological agents. Effects of Rotations and Manure Compost on Nematode Communities in Organic Farming Systems A large farming systems trial, begun in 1999 to evaluate transition methods for conversion from conventional to organic farming practices, was continued through 2013. A vegetable crop trial evaluated a high input, compost intensive management system versus a low-input system that relies on green manures and cover crops. High input treatments received 10 tons/acre of composted dairy manure annually and were planted to one of four vegetable families in rotation: legumes (beans and peas), Solanaceae (pepper and tomato), cucurbits (squash and pumpkin), and leafy vegetables (lettuce and spinach). Hairy vetch, cowpea and buckwheat were planted as cover crops to boost soil fertility and organic matter content. The treatments were repeated with a field crop trial where the high input plots were planted to wheat, soybean, corn, or forage rape. The field crop treatments were also factored into plots with or without animal grazing (sheep) beginning in 2001. Soil samples were collected preplant and late season in each year and were analyzed for plant-parasitic and predatory nematodes, and assayed for nematode biocontrol agent activity. Common nematodes found include Pratylenchus crenatus, Xiphinema rivesi, Helicotylenchus spp., Hoplolaimus spp. Meloidogyne hapla, and Clarkus papillatus (predator). Population densities remained low for all plant parasites throughout the 15 years of this experiment and few differences among compost treatments or crops were statistically significant. Novel Nematode Management Options in Peach Orchards Two trials comparing five nematicide treatments in peach orchards were initiated in 2014 and continued in 2015. At the Kearneysville Fruit Tree Research and Education Center in Jefferson County, WV, plots consisted of three 12-year-old trees of cv Bounty on Halford rootstocks. All products are commercially available for nematode control on peach, but have very little information regarding efficacy on nematodes problematic in Mid-Atlantic peach orchards (Xiphinema, Mesocriconemella, and Pratylenchus). Treatments were applied May 8, 2014 and May 13, 2015 (about 1 week after petal fall). Movento (spirotetramet) was applied to foliage in 1000 Gal water/acre with an airblast sprayer at 0.63 Kg/Ha (9oz/A). Other materials were applied to the herbicide strip beneath trees and included: 1) DiTera (Myrothecium verrucaria) granules at 117 kg/Ha (104 lb/A); 2) Ecozin Plus-Spring (azadirachtin) at 2.1 kg/Ha (1.875 lb/A), applications were repeated 2 and 4 weeks later; 3) Ecozin Plus-Spring & Fall. as above, with applications repeated in Fall; and 4) Nema-Q (Quillaria saponaria, Soapwood extract) at 14 L/Ha (1.5 Gal/A). All plots, including untreated controls were sprayed with tap water at 1000 gal/acre (~0.1 cm) to incorporate the materials, later applications relied on rainfall. Soil samples were collected for nematode assay, and trunk diameters were measured, on May 8 (pre-treatment) and again on June 19 and Oct. 7, 2014. In 2015, soil samples were collected May 13, July 28, and Oct. and Nov. 7. A second site was established in Hampshire County, WV at a commercial orchard exhibiting losses to stem pitting. Plots consisted of twelve 5-year-old peach trees (cv. Contender on Bailey rootstock). Treatments were applied to soil on May 14, 29014, and repeated on May 16, 2015 and included 1) Ditera, 2) Ecozin (Spring only), and 3) Nema-Q at the same rates as above. The Ecozin treatment was repeated on May 28, 2014, and on May 31 and June 14, 2015. Soil samples and trunk diameters were collected on May 14 and again on Oct 7, 2014. Xiphinema rivesi was the dominant dagger nematode at the Kearneysville site whereas the Hampshire County site was dominated by Xiphinema americanum. Nematode populations did not differ significantly from controls in either year, nor did tree growth or survival differ significantly among nematicide treatments. The sprayer irrigation and reliance on natural rainfall may have been insufficient for adequate incorporation of these products. Final measurements will be collected in Spring, 2016. Mode of action of Bacillus firmus for nematode biocontrol Laboratory and greenhouse trials evaluated the bacterium Bacillus firmus for control of dagger nematode, Xiphinema americanum, and root knot nematode, Meloidogyne hapla, and to determine the mode of action. There was no evidence of direct toxicity to either nematode, nor was egg production per female affected by B. firmus with M. hapla. An attraction assay demonstrated that M. hapal juveniles was attracted to a soil extract, but not to B. firmus in vitro. Roots of tomato dipped in a suspension of B. firmus attracted significantly fewer M. hapla than roots dipped in a soil extract control. However, B. firmus had no significant effect on attraction of Xiphinema americanum. Objective 2. Evaluate cultural management procedures for plant-parasitic nematodes in relation to their impacts on the sustainability of soil health: With special reference to the utility of nematode community structure as an indicator of overall soil quality and their roles in plant nutrient cycling. No new progress. Objective 3. Provide educational materials and programs on cultural management of plant-parasitic nematodes and sustainable soil health systems as a component of on-going extension and outreach efforts. No new progress.
Publications
|
Progress 10/01/13 to 09/30/14
Outputs
Target Audience: The primary target for this research is growers who are experiencing losses from plant-parasitic nematodes. Additional targets include extension personnel, crop advisors and others. Efforts included outreach at the WVU Organic Research Farm Field Day, Aug. 6, 2014 with workshops attended by approximately 110 individuals. Additional outreach included orchard growers as part of a nematode survey in 2014. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? A graduate student has begun work to evaluate the effects of Bacillus firmus on dagger and root lesion nematodes. How have the results been disseminated to communities of interest? We prepared a workshop at the WVU organic Farm Field Day to discuss parasitic nematodes. Nematicide recommendations are undergoing revisions and will be presented in regional Fruit production guides. What do you plan to do during the next reporting period to accomplish the goals? Population density and activity of nematode biocontrol agents will continue to be monitored in organic farming systems. Soils will be assayed to determine whether suppressiveness is biologically mediated and can be re-established in sterilized soils. Farming systems research will evaluate the effects of compost amendments and rotations in organic vegetable and field crop production systems on nematode community structure. Soil suppressiveness to nematodes and population dynamics of indigenous biocontrol agents will be compared with emphasis on isolating biological controls for root knot and root lesion nematodes. A new project was initiated in 2014 to improve nematode management by evaluating the mode of action of a new commercially-available nematode biocontrol agent, Bacillus firmus. Early research suggests it produces nematicidal secondary metabolites, while later work implicated induced resistance in the host. Trials will evaluate nematode survival when incubated in solutions of B. firmus, as well as to assess nematode attraction to roots, infection and reproduction. Peach nematicide trials will be repeated in 2015, with additional efforts to assess effects on non-target biocontrol agents. Results in 2014 will provide a screening assessment of efficacy and tree response, and will be used to propose improved nematode management plans for growers. Analyses in 2015 and 2016 will provide multi-year data to determine perennial tree fruit response and assess performance of grower nematode management plans.
Impacts
What was accomplished under these goals?
Objective 1. Develop effective and economically viable cultural management tactics for plant-parasitic nematodes based on host resistance, nematode-antagonistic rotation or cover crops, soil amendments and biological agents. Effects of Rotations and Manure Compost on Nematode Communities in Organic Farming Systems A large farming systems trial, begun in 1999 to evaluate transition methods for conversion from conventional to organic farming practices, was continued through 2013. A vegetable crop trial evaluated a high input, compost intensive management system versus a low-input system that relies on green manures and cover crops. High input treatments received 10 tons/acre of composted dairy manure annually and were planted to one of four vegetable families in rotation: legumes (beans and peas), Solanaceae (pepper and tomato), cucurbits (squash and pumpkin), and leafy vegetables (lettuce and spinach). Hairy vetch, cowpea and buckwheat were planted as cover crops in in 2011 and 2012. The treatments were repeated with a field crop trial where the high input plots were planted to wheat, soybean, corn, or forage rape. The field crop treatments were also factored into plots with or without animal grazing (sheep) beginning in 2001. Soil samples were collected preplant and late season in each year and were analyzed for plant-parasitic and predatory nematodes, and assayed for nematode biocontrol agent activity. Common nematodes found include Pratylenchus crenatus, Xiphinema rivesi, Helicotylenchus spp., Hoplolaimus spp. Meloidogyne hapla, and Clarkus papillatus (predator). Population densities remained low for all plant parasites throughout the 14 years of this experiment and few differences among compost treatments or crops were statistically significant. Novel Nematode Management Options in Peach Orchards Two trials are underway comparing five nematicide treatments in peach orchards. At the Kearneysville Fruit Tree Research and Education Center in Jefferson County, WV, plots consisted of three 12-year-old trees of cv Bounty on Halford rootstocks. All products are commercially available for nematode control on peach, but have very little information regarding efficacy on nematodes problematic in Mid-Atlantic peach orchards (Xiphinema, Mesocriconemella, and Pratylenchus). Treatments were applied May 8 (about 1 week after petal fall). Movento (spirotetramet) was applied to foliage in 1000 Gal water/acre with an airblast sprayer at 0.63 Kg/Ha (9oz/A). Other materials were applied to the herbicide strip beneath trees and included: 1) DiTera (Myrothecium verrucaria) granules at 117 kg/Ha (104 lb/A); 2) Ecozin Plus-Spring (azadirachtin) at 2.1 kg/Ha (1.875 lb/A), applications were repeated 2 and 4 weeks later; 3) Ecozin Plus-Spring & Fall. as above, with applications repeated in Fall; and 4) Nema-Q (Quillaria saponaria, Soapwood extract) at 14 L/Ha (1.5 Gal/A). All plots, including untreated controls were sprayed on May 8 with tap water at 1000 gal/acre (~0.1 cm) to incorporate the materials, later applications relied on rainfall. Soil samples were collected for nematode assay, and trunk diameters were measured, on May 8 (pre-treatment) and again on June 19 and Oct. 7. A second site was established in Hampshire County, WV at a commercial orchard exhibiting losses to stem pitting. Plots consisted of twelve 5-year-old peach trees (cv. Contender on Bailey rootstock). Treatments were applied to soil on May 14 and included 1) Ditera, 2) Ecozin (Spring only), and 3) Nema-Q at the same rates as above. The Ecozin treatment was repeated on May 28. Soil samples and trunk diameters were collected on May 14 and again on Oct 7, 2014. Xiphinema rivesi was the dominant dagger nematode at the Kearneysville site whereas the Hampshire County site was dominated by Xiphinema americanum. No significant differences among nematode populations were observed, nor did tree growth or survival differ significantly among nematicide treatments. The sprayer irrigation and reliance on natural rainfall may have been insufficient for adequate incorporation of these products. These trials will be repeated in 2015. Objective 2. Evaluate cultural management procedures for plant-parasitic nematodes in relation to their impacts on the sustainability of soil health: With special reference to the utility of nematode community structure as an indicator of overall soil quality and their roles in plant nutrient cycling. No new progress. Objective 3. Provide educational materials and programs on cultural management of plant-parasitic nematodes and sustainable soil health systems as a component of on-going extension and outreach efforts. No new progress.
Publications
|
Progress 01/01/13 to 09/30/13
Outputs
Target Audience: The primary target for this research is growers who are experiencing losses from plant-parasitic nematodes. Additional targets include extension personnel, crop advisors and others. Efforts included outreach at the WVU Organic Research Farm Field Day, Aug. 9, 2013 with workshops attended by approximately 100 individuals. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? One graduate student has initiated a Masters thesis in support of this project. Two undergraduate students (Elaina Spahr and Courtney Rice) have participated in greenhouse and laboratory trials in 2013. James Kotcon attended the Society of Nematologists meeting and the NE-1040 Nematology Regional research technical committee meeting. How have the results been disseminated to communities of interest? Nematode diagnostic services and management recommendations are submitted to individual growers. Results are also published in annual Tree Fruit Extension guides. What do you plan to do during the next reporting period to accomplish the goals? Nematode population dynamics in long-term farming systems trials at the WVU Organic Research Farm will continue to be monitored. A trial to evaluate nematode resistance in tomato will be repeated. We will evaluate the efficacy of some new commercially-available nematode biocontrol agents, Nema-Q (Quillaria saponaria), DiTera (Myrothecium verrucaria) and Neem extracts (Molt-X, Ornazin)) and a new chemical nematicide (Movento, spirotetramet) against dagger nematode (Xiphinema spp.) in peach orchards at the WVU Kearneysville Tree Fruit Research and Education Center. We will assess tree growth and yield to determine potential benefits of these novel nematode management practices, and to improve grower nematode management plans for problem orchards. Nematode population densities and trunk diameters will be determined prior to application, and each spring and fall thereafter.
Impacts
What was accomplished under these goals?
A large farming systems trial, begun in 1999 to evaluate transition methods for conversion from conventional to organic farming practices, was continued through 2013. A vegetable crop trial evaluated a high input, compost intensive management system versus a low-input system that relies on green manures and cover crops. High input treatments received 10 tons/acre of composted dairy manure annually and were planted to one of four vegetable families in rotation: legumes (beans and peas), Solanaceae (pepper and tomato), cucurbits (squash and pumpkin), and leafy vegetables (lettuce and spinach). Hairy vetch, cowpea and buckwheat were planted as cover crops in in 2011 and 2012. The treatments were repeated with a field crop trial where the high input plots were planted to wheat, soybean, corn, or forage rape. The field crop treatments were also factored into plots with or without animal grazing (sheep) beginning in 2001.Soil samples were collected preplant and late season in each year and were analyzed for plant-parasitic and predatory nematodes, and assayed for nematode biocontrol agent activity. Common nematodes found include Pratylenchus crenatus, Xiphinema rivesi, Helicotylenchus spp., Hoplolaimus spp. Meloidogyne hapla, and Clarkus papillatus (predator). Population densities remained low for all plant parasites throughout the 14 years of this experiment and few differences among compost treatments or crops were statistically significant. A trial comparing five summer cover crops was initiated in 2013 as part of the vegetable farming systems trial described above. High input plots received 10 tons per acre of dairy manure compost as a soil fertility amendment, and were planted to buckwheat as a summer cover crop. Four replicate plots each in the low input (no compost) treatment were planted to four legume cover crops (soybean, cowpea, sunn hemp, and sesbania) to build soil fertility. Nematode samples were collected Sept. 7. Population densities of lesion, spiral, and Mononchus nematodes were highest on sesbania, while dagger nematode populations were lowest on sesbania and greatest on sunn hemp. Differences among crops were not statistically significant. New experiments were initiated to compare efficacy of biocontrol agents of Xiphinema spp in peach, including Bacillus firmus, Pasteuria, and other new agents labeled for commercial release. Field trials and lab experiments are planned for 2014.
Publications
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Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: Laboratory experiments evaluated the mode of action of Neem products for suppression of root knot nematodes in tomato. We tested the hypotheses that Neem affects motility, host finding ability, and life cycle of root-knot nematodes. Three layers of soil were placed in 250-cm3 pots. The bottom layer contained 50 cm3 of steamed soil. Nematode inoculum (2,500 M. incognita eggs per pot) was pipetted onto the bottom layer. The middle layer contained 50 cm3 soil with three treatments: control, soil layer, and drench. The soil layer and drench treatments both contained Neem oil at label rates (0.2 g/kg steamed soil). The middle soil layer of controls was without Neem oil. Wire mesh was placed over the middle soil layer, and 150 cm3 steamed soil was added as a top layer. Tomato seedlings were transplanted into the steamed soil in the top layer. The drench treatment then also received weekly Neem drenches (0.016g Neem oil in 10 ml water). The effect of Neem on nematode movement was assessed by counting nematodes in upper and lower portions of the root systems after 6, 13, 21, and 34 days. The experiment was repeated with a comparison of M. hapla versus M. incognita receiving the drench treatment or control. A third experiment compared untreated controls versus drench treatments of Neem oil and an azadirachtin product (Molt-X) on both M. hapla and M. incognita. In the first experiment, more M. incognita galls were found in the upper portion of the soil layer treatment than the lower, however, the opposite occurred with the drench treatment. The number of mature females did not differ among treatments with versus without Neem oil. Similar results were found in the second experiment with Neem oil suppressing galling by M. incognita, however, Neem oil had no significant effect on M. hapla root infection. In the third experiment, no differences among soil layers occurred for the Neem oil or Molt-X treatments, suggesting no effect on nematode movement. By 33 days after transplanting, M. incognita galling with both Neem Oil and Molt-X was less than in controls, whereas differences among treatments were not statistically significant for M. hapla. A field trial was initiated with switchgrass (Panicum virgatum) cultivars Alamo, Cave-In-Rock, Kanlow, Performer and Shawnee, as well as big blue stem (Andropogon gerardii), coastal panic grass (Panicum amarum), and orchard grass (Dactylis glomerata) planted in 2008 in 1-m2 plots amended with or without dairy manure compost. Yield data and soil samples were collected in fall, 2011. No significant differences were observed in populations densities of Xiphinema, Pratylenchus, or Mononchus, however populations densities of Helicotylenchus spp. (mostly H. dihystera and H. pseudorobustus) were significantly greater with Kanlow than with big blue stem, Alamo, Performer, or Cave-In-Rock. Total yields differed significantly among grass genotypes. Compost amendment had no significant effect on yields or nematode densities. When broad-leaf weeds were excluded, yields of grasses were negatively correlated with population densities of Helicotylenchus spp. PARTICIPANTS: James Kotcon, PI. Oversaw nematode experiments, provided training for students. Training included independent study rojects for four students; Caroline Copenhaver, Courtney Rice, Susanna Wheeler, and Swetha Doppalapudi. TARGET AUDIENCES: The primary target for this research is growers who are experiencing losses from plant-parasitic nematodes. Additional targets include extension personnel, crop advisors and others. Efforts included outreach at the WVU Organic Research Farm Field Day, Aug. 2, 2012 with workshops attended by approximately 150 individuals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Results suggest that Neem reduces motility of M. incognita, but is not directly toxic nor does it affect molting or development of nematodes, as it does in insects. Future research will focus on species-specific differences. The primary impact of this research is to identify improved management approaches that take advantage of a better understanding of the mode of action of these products. correlations of switch grass uyield and nematode population densities will be repeated through 2013.
Publications
- No publications reported this period
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Progress 01/01/11 to 12/31/11
Outputs
OUTPUTS: A large farming systems trial, begun in 1999 to evaluate transition methods for conversion from conventional to organic farming practices, was continued through 2010. Common nematodes found include Pratylenchus crenatus, Xiphinema rivesi, Helicotylenchus spp., Tylenchorhynchus spp. Meloidogyne hapla, and Clarkus papillatus (predator). Population densities remained low for all plant parasites throughout the ten years of this experiment and few differences among compost treatments or crops were statistically significant. Increases over the growing season were not observed, suggesting the presence of suppressive soils. Bacterial feeding nematodes tended to increase over the trial, but differences among compost treatments were not significant at any date. The experiment will continue through 2012. The mode of action of Neem products for suppression of Meloidogyne incognita and M. hapla in tomato was evaluated in laboratory trials. We tested whether Neem affects motility, host finding ability, and life cycle of root-knot nematodes. Three layers of soil were placed in 250-cm3 pots. The bottom layer contained 50 cm3 of steamed soil. Nematode inoculum (2,500 M. incognita or M. hapla eggs per pot) was pipetted onto the bottom layer. The middle layer contained 50 cm3 soil with three treatments: control, soil layer, and drench. The soil layer and drench treatments both contained Neem oil at label rates (0.2 g/kg steamed soil). The middle soil layer of controls was without Neem oil. Wire mesh was placed over the middle soil layer, and 150 cm3 steamed soil was added as a top layer. Tomato seedlings were transplanted into the steamed soil in the top layer. The drench treatment received weekly Neem drenches (0.016g Neem oil in 10 ml water). After 10, 20, and 40 days, roots of three replicates of each treatment were harvested separately from above and below the screen, bleached and stained. The effect of Neem on nematode movement was assessed by counting nematodes in upper and lower portions of the root systems. Neem suppressed gall number in tomato roots inoculated with M. incognita, especially at 40 days after inoculation, but not roots inoculated with M. hapla. Neem also suppressed plant dry weight in this trial. A field trial was initiated to evaluate Sunn Hemp (Crotalaria juncea) as a cover crop for nematode and weed suppression in vegetable and orchard sites. Initial samples showed no differences among treatments. Five cultivars of switchgrass were planted in 1X1m plots with or without 10 T/A dairy manure compost in 2008 to assess the role of nematodes. Little growth was seen in 2009 or 2010, but switchgrass dominated the plots in 2011. Yields of orchard grass yields were lowest, with Atlantic,Performer and Cave-In-Rock yielding less than Big Bluestem, Shawnee or Alamo. Compost did not affect yields. Population density of Pratylenchus, Xiphinema, and Mononchus did not differ among treatments, but Helicotylenchus populations were lower on Big Bluestem and Performer than on Kanlow, Atlantic, or orchard grass. Total biomass was negatively correlated with population density of Helicotylenchus. PARTICIPANTS: James Kotcon is Associate Professor of Plant and Soil Sciences. Collaborators in this multi-state project include George Abawi, Cornell University; George Bird, Michigan State University, Don Dickson, University of Florida; John Halbrendt, Pennsylvania State University; Robin Huettel; Auburn University; James LaMondia, Connecticut Agricultural Experiment Station; Nathaniel Mitkowski, University of Rhode Island and Judy Thies, USDA South Carolina. TARGET AUDIENCES: The primary target audiences are growers, crop specialists and extension agents concerned about plant parasitic nematodes. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Use of chemical nematicides has been restricted, requiring alternative nematode management practices. Use of crop rotation and organic amendments could reduce nematode populations. These studies demonstrate that two organic farming systems have suppressed plant-parasitic nematodes, although the mechanisms remain undetermined. Alternative nematicidal materials such as Neem oil or suppressive rotation crops such as Sunn Hemp are needed as conventional chemical nematicides are removed from the market. A better understanding of their mode of action, as well as their efficacy against various nematode species, will be required to use these tactics effectively.
Publications
- No publications reported this period
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Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: A large farming systems trial, begun in 1999 to evaluate transition methods for conversion from conventional to organic farming practices, was continued through 2010. Common nematodes found include Pratylenchus crenatus, Xiphinema rivesi, Helicotylenchus spp., Tylenchorhynchus spp. Meloidogyne hapla, and Clarkus papillatus (predator). Population densities remained low for all plant parasites throughout the ten years of this experiment and few differences among compost treatments or crops were statistically significant. Increases over the growing season were not observed, suggesting the presence of suppressive soils. Bacterial feeding nematodes tended to increase over the trial, but differences among compost treatments were not significant at any date. The experiment will continue through 2011. Laboratory experiments evaluated the mode of action of Neem products for suppression of Meloidogyne incognita in tomato. Neem is claimed to be nematicidal and is approved for organic crop production, however, its mode of action is unknown. We tested the hypotheses that Neem affects motility, host finding ability, and life cycle of root-knot nematodes. Three layers of soil were placed in 250-cm3 pots. The bottom layer contained 50 cm3 of steamed soil. Nematode inoculum (2,500 M. incognita eggs per pot) was pipetted onto the bottom layer. The middle layer contained 50 cm3 soil with three treatments: control, soil layer, and drench. The soil layer and drench treatments both contained Neem oil at label rates (0.2 g/kg steamed soil). The middle soil layer of controls was without Neem oil. Wire mesh was placed over the middle soil layer, and 150 cm3 steamed soil was added as a top layer. Tomato seedlings were transplanted into the steamed soil in the top layer. The drench treatment received weekly Neem drenches (0.016g Neem oil in 10 ml water). After 6, 13, 21, and 34 days, roots of three replicates of each treatment were harvested separately from above and below the screen, bleached and stained. The effect of Neem on nematode movement was assessed by counting nematodes in upper and lower portions of the root systems. In the soil layer treatment, more nematodes were found in the upper portion of the soil than the lower (P = 0.018), however, the opposite occurred with the drench treatment. The number of mature females did not differ among Neem treatments. In an in vitro experiment nematodes were suspended in dilute Neem oil. At higher Neem concentrations, nematodes moved more slowly than nematodes in distilled water. Nematodes remained alive for at least three days. Results suggest that Neem reduces motility of nematodes, but is not directly toxic nor does it affect molting or development of nematodes, as it does in insects. The experiment was being repeated with a comparison of M. incognita versus M. hapla. Neem again suppressed M. incognita, but had no significant effect on M. hapla. A field trial was initiated to evaluate Sunn Hemp (Crotalaria juncea) as a cover crop for nematode and weed suppression in vegetable and orchard sites. Initial samples showed no differences among treatments. PARTICIPANTS: James Kotcon is Associate Professor of Plant and Soil Scioences. Collaborators in this multi-state project include George Abawi, Cornell University; George Bird, Michigan State University, Don Dickson, University of Florida; John Halbrendt, Pennsylvania State University; Robin Huettel; Auburn University; James LaMondia, Connecticut Agricultural Experiment Station; Nathaniel Mitkowski, University of Rhode Island and Judy Thies, USDA South Carolina. TARGET AUDIENCES: The primary target audiences are growers, crop specialists and extension agents concerned about plant parasitic nematodes. PROJECT MODIFICATIONS: None.
Impacts
Use of chemical nematicides has been restricted, requiring alternative nematode management practices. Use of crop rotation and organic amendments could reduce nematode populations. These studies demonstrate that two organic farming systems have suppressed plant-parasitic nematodes, although the mechanisms remain undetermined. Alternative nematicidal materials such as Neem oil or suppressive rotation crops such as Sunn Hemp are needed as conventional chemical nematicides are removed from the market. A better understanding of their mode of action, as well as their efficacy against various nematode species, will be required to use these tactics effectively.
Publications
- King, T. N. and J. B. Kotcon. 2010. Reproduction of Pratylenchus penetrans in soils with and without Pasteuria spp. Abstract. Presented at Society of Nematologists annual meeting, Boise Idaho.
- Kotcon, J. B. 2010. Population dynamics of earthworms in organic farming systems. Pp. 299-310. In Karaca, A. (ed.) Biology of Earthworms. Springer-Verlag. Berlin.
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