Vine Decline Management for Ontario: A Work in Progress Janice LeBoeuf, OMAFRA, Ridgetown
Numerous Projects in 2009 and 2010 Project Project team (funding) Year; Location Informal survey of vine decline sites Culture-based identification of corky root rot in processing tomatoes Assessing biofumigant cover crops: practicality, effectiveness, impact on soil health Survey for vine decline in Ontario processing tomato J. LeBoeuf, OMAFRA; Tomecek Ag. Services; J.A. Traquair and B.L. Singh, AAFC London; C. Trueman, Ridgetown Campus J.A. Traquair and B.L. Singh, AAFC London; J. LeBoeuf, OMAFRA; C. Trueman, Ridgetown Campus A. Verhallen, OMAFRA; J. LeBoeuf, OMAFRA (OMAFRA Environmental Sustainability Research Program) J.A. Traquair, AAFC London; J. LeBoeuf, OMAFRA; K. Conn, AAFC London; P. Abbasi, AAFC London; K. Wang, A&L Canada Labs (OTRI) 2009; fields across Essex and Kent sampled for pathogens (fungal, bacterial, nematodes) 2009; AAFC-London (samples from fields across Essex, Kent) 2009-2010; commercial fields 2010; AAFC-London (samples from fields across Essex, Kent) cont d
Numerous Projects in 2009 and 2010 Project Project team (funding) Year; Location Prelim. investigations into the ecology and management of pathogenic organisms contributing to vine decline in Ontario processing tomatoes Advancing the competitiveness of Ontario s processing tomato industry by piloting innovative solutions to emerging root disease pressures causing vine decline C. Trueman, Ridgetown Campus; K. Conn, AAFC London; J.A. Traquair, AAFC London (OTRI, OMAFRA-Univ. of Guelph) S. Loewen, Ridgetown Campus; G. Lazarovits, A&L Biologicals Agroecology Research Services (Canadian Agricultural Adaptation Program, OTRI) 2010; lab, greenhouse, micro-plots, commercial field 2010; lab, field
Learning About The Problem Identification of the corky root pathogens and other soil pathogens infecting tomato roots biology, hosts - previous presentation Other stresses identified through informal surveying: foliar pathogens, nematodes, compacted zones in soil. Others? Impacts? Lots to learn about interactions. Corky root symptoms widespread across the growing area big differences in severity depending on the field, season.
Prelim. investigations into the ecology and management of pathogenic organisms contributing to vine decline in Ontario processing tomatoes C. Trueman, Ridgetown Campus; K. Conn, AAFC London; J.A. Traquair, AAFC London
WHAT CAN WE DO ABOUT VINE DECLINE? Overall objectives: 1. Obtain preliminary information on role of different pathogens on the development of corky root and vine decline symptoms. 2. Obtain preliminary information on the potential of biological and chemical control products. Approach in 2010 for Objective 2: 1. Winter greenhouse trial with infested soil from Essex County 2. Outdoor microplot trial with infested soil from Kent County 3. Field trial at commercial site in Kent County
GREENHOUSE Figure 1. Number of banded lesions per gram of dry root on tomato roots grown in infested soil in greenhouse conditions and treated with various materials for management of vine decline symptoms, Ridgetown, 2010. a ab bc bc bc c c c
OUTDOOR MICROPLOTS Table 1. Number and weight of tomato fruit harvested, and number of lesions per cm of root, from tomatoes grown in micro-plots in soil previously associated with vine decline symptoms in processing tomato, 2010. Treatment Number of Fruit Weight (kg) Lesions/cm Root Nontreated 37.7 b a 1.52 b 1.9 ns Vapam - MEDIUM 44.1 ab 1.95 ab 1.9 Vapam - HIGH 66.8 a 2.88 a 1.5 Actigard 1x 35.8 b 1.37 b 2.6 Actigard 2x 55.0 ab 1.88 ab 2.0 a Numbers in a column followed by the same letters are not significantly different at P = 0.05, based on Tukey s adjustment, ns = not significant. -Did death of microorganisms result in a release of nutrients? -Was soil repopulated with different spectrum of microorganisms?
COMMERCIAL FIELD TRIAL Figure 2. Tomato yield and number of banded root lesions on plants grown at a commercial field site and in soil fumigated with Vapam (metam sodium) for management of tomato vine decline, Kent County, 2010. ns ns ns -Total yield from two 2m sections in each replicate -Banded lesions (wrapping around the full circumference of the root) on the four (Sept. 17) or five (July 14) largest roots on each root ball. Average of 48 root balls (12 plants/replicate).
PRELIMINARY CONCLUSIONS & FUTURE RESEARCH The ability of Vapam to reduce symptoms of vine decline on roots is inconsistent. The number of banded lesions was lower than the nontreated in the greenhouse trial, but not in micro-plot and field trials. The yield increase observed in the microplots treated with the high rate of Vapam should be investigated further. The yield increase occurred despite the fact that there was no significant reduction in the number of banded lesions on roots. Research will be repeated in 2011, with additional work to explore the influence of different pathogens in the vine decline complex.
ACKNOWLEDGEMENTS Grower cooperators who donated soil and/or research sites Agris, UAP, Bioworks, Heinz, and Sunbrite for donating supplies and materials Ontario Tomato Research Institute OMAFRA / U of G Research Program Agriculture and Agri-Food Canada
Advancing the competitiveness of Ontario s processing tomato industry by piloting innovative solutions to emerging root disease pressures causing vine decline S. Loewen, Ridgetown Campus; G. Lazarovits, A&L Biologicals Agroecology Research Services Funding: Canadian Agricultural Adaptation Program OTRI
2010 Activities Field trial - grew plants resulting from grafting a common scion onto many different roots Collected soil and root samples from 10 different sites (healthy and diseased) try to determine differences in soil microbes or soil chemical properties Developed PCR primers for quick ID of corky root and fusarium species used to test samples (above) Culturing soil pathogens in the presence of disease-suppressive bacteria isolated from tomato roots
Rootstock trial
Progress Molecular diagnostics Can detect major pathogens Working on quantifying results Biological soil health tests underway Relationship between plant vigour and total microbial activity 1 0.9 0.8 Relative units 0.7 0.6 0.5 0.4 0.3 0.2 0.1 fruit weight shoot weight FDA 0 7006 7010 7011 7012 7013 7014 7015 7019 7020 7023 7025 7026 Graftng combination
Testing Biocontrol Bacteria 1. Co-culture bacteria with fungal pathogens and look for inhibition 2. Test isolates in growth chamber, then in field conditions Pyrenochaeta lycopercisi Rhizopycnis vagum Colletotrichum coccodes
Conclusions 1. A rootstock exists that resists vine decline Traits could be used by breeders, but possibly tied to undesirable traits? 2. Production systems exist that do not have vine decline Provides a model system to understand why 3. Vine decline may be caused by a complex of organisms 4. Potential for biocontrol by bacteria
Assessing biofumigant cover crops: practicality, effectiveness, impact on soil health Anne Verhallen, Janice LeBoeuf, OMAFRA, Ridgetown Funding: OMAFRA Environmental Sustainability Directed Research Program
Biofumigant cover crops Not specific to corky root, but to general crop health and yield impacts (ie. not evaluating reduction in root lesions, but measuring yield) Also measuring soil health, nematode and verticillium levels at some locations Part of the project is to evaluate how practical it is to fit biofumigation into a commercial tomato operation (time to grow cover crop, chop and incorporate, waiting period before transplanting?) Compare biofumigation to no treatment; at some locations also comparing to chemical fumigation
Biofumigant cover crops One year completed of a two-year project Spring seeding vs. fall seeding Need to chop and incorporate; otherwise you ve provided a nematode host Waiting period after incorporation (spring) Soil temperature important as with fumigants Growth and glucosinolate content are both important Efficacy will analyze results after 2 years
Coordinated Research Effort To summarize
Work in progress Understanding the fungal pathogens involved Improving detection; potential for pre-screening fields Examining interactions between the corky root pathogens, other pathogens, other factors Looking for tolerance in the tomato germplasm Investigating soil biology and beneficial microbes that could suppress the disease Investigating fumigation, biofumigation, SAR products Investigating the role of nematodes* Management practices: crop rotation/cover crops, organic amendments (manure, compost, green manure),??? * * If funding available