Present practice, on going research. vegetable production in Denmark

Transcription

1 Present practice, on going research and future potential for nonchemical disease management in vegetable production in Denmark

2 Outline Available non chemical methods to control plant diseases Present non chemical disease management in Denmark Ongoing research Future perspectives

3 Available methods Resistant varieties Crop rotation Alternative crops Biofumigation Mechanical control of soilborne diseases Thermal control of soilborne diseases Changeofsowing time Biological management Microbiological products Botanicals

4 Resistant varieties Breeding programs within most vegetables allo gro ers to ha e a range of varieties allow growers to have a range of arieties available The problem is rather that plants are bred against higher yield and quality of yield rather than disease resistance Prima, healty soil Prima, infested Sabine Ravnskov Department of Agroecology, Aarhus University Borweta, healty soil Borweta, infested soil Chinese Danish workshop Aarhus University 22 August 2012

5 Crop rotation MostDanish plant producers have rather healthy crop rotation programs according to present knowledge However, there is a need for more knowledge to deal with e.g. pathogens that can survive in soil for many years

6 Alternative crops Healthy soil Infested with lupin pathogens Sabine Ravnskov Department of Agroecology, Aarhus University Infested with pea pathogens Chinese Danish workshop Aarhus University 22 August 2012

7 Biofumigation -R. solani +R. solani Oat Rye Turnip White mustard Rape Oil radish Marigold Red clover White clover Afric rican marigold Wheat Green manure crop 3 2,5 2 1,5 1 0,5 0 None Oat White mustard Diseased ste ms (%) Rhizoctonia solani infestation (Scale 0-4) Pre-crop 13 % less incidence of disease after oat

8 Mechanical soil treatment i infestation n ale 0-4) tonia solan scoring sca Rhizoc (s 3 2,5 2 1,5 1 0,5 0 Plow Harrow Mechanical soil treatment before sowing Less disease and 15% higher yield from ploughed soil

9 Thermal control ction (%) Effect of steam on diseases in carrots Steam C Steam C Infe Cavity spot Patogen Scab

10 Change of sowing time Incidence of disease sympto oms (R Relative sca ale 0 4) 2 1,5 1 0,5 0 Incidence of disease symtoms caused by Rhizoctonia solani (AG3) i potato as influenced by time of sowing Early 20/4) Normal (3/5) Late (20/5) Time of sowing

11 Approved products for biological management of diseases in vegetables Contans WG (Coniothyrium minitans) against Sclerotinia sclerotiorum in lettuce Mycostop (Streptomyces) against Fusarium in tomato 5 different products based on Tih Trichoderma used against both soilborne diseases and against Botrytis cinerea in tomatot (Prestop based on Gliocladium against Didymella bryoniae cucumbernulatum)

12 Ongoing research at AU Focus on how agroecological mechanisms can be used in more holistic plant management strategies Multifunctional organisms Integrated agroecological control of diseases, pest and weeds

13 Multifunctional plant beneficial microorganisms i may increase plant nutrient uptake growth tolerance against abiotic stress tolerance l against biotic stress Some microbes cover part of these capabilities, Arbuscular mycorrhizal (AM) fungi cover all of them

14 Arbuscular mycorrhizal fungi Obligate biotrophic Forms symbioses with % of plants Important for plant nutrition Increase plant stress tolerance Form a mycorrhizosphere, h extent action zone for plants Considered as an ecosystem service

15 Abundance of AM fungi in Pisum sativum roots correlates withroot healthstatus 26 different OTUs of AM fungi in these roots Yu et al. 2012, Plant and Soil 357:

16 Perspectives Plant protection of organic vegetables should be based on a holistic ecological strategy, muchmoreinterdiciplinarymore research is needed bothby by Integrating research in agroecological control of diseases, pests and weeds Combining more approaches to control diseases in an overall strategy (resistance, thermal/mechanical control, crop rotation/biofumigation, biocides) Furthermore, there is a need to focus on how application of biocides can be implemented and used by growers Diversification of vegetable cropping systems to optimize exploitation of agroecological mechanisms in plant protection