Impact of Silicon Amendments on Strawberry Powdery Mildew Control in Poly-tunnel and Field Productions M-H. Goyette 1*, S. Ouellette 1, L. Gaudreau 1, M. Dorais 1,2, A. Van Sterthem 3, A. Gosselin 1 and R.R. Bélanger 1 1 Département de phytologie, Faculté des Sciences de l agriculture et de l alimentation, Centre de Recherche en Horticulture, Université Laval, Québec, QC, Canada, G1V 0A6; 2 Agriculture and Agri-Food Canada, Pacific Agri-Food Research Centre, Agassiz, BC, Canada, V0M 1A0; 3 Recherche et développement, Les Fraises de l'île d'orléans Inc., Saint-Laurent-de-l'Île-d'Orléans, QC, Canada, G0A 3Z0 19/09/2016
71% Strawberry samples in Canada have pesticide residues (2009-2010) 29% 71% no residues pesticides Strawberries in Canada 22% fungicides against strawberry powdery mildew Source: ACIA, 2009 2010
71% Strawberry samples in Canada have pesticide residues (2009-2010) 71% 29% no residues pesticides Strawberries in Canada 0,4% herbicide residues 22,4% insecticide residues 77,2% fungicide residues 22% fungicides against strawberry powdery mildew Source: ACIA, 2009 2010
Why do we need to control strawberry powdery mildew?
Because... Decrease in yield (mostly for day neutral) e.g. In Québec, yield loss caused by strawberry powdery mildew, can reach 9%-30% in Seascape cultivar (Carisse et al. 2013)
MYCELIUM ON LEAVES Goyette, M. 2015 Ouellette, S. 2015 Ouellette, S. 2015
REDDISH SPOTS ON LEAVES
LEAF ROLL
...causing then a massive use of fungicides More than 60% chemical fungicides registered are Strobilurins and Triazoles High resistance risk! (Fernández-Ortuňo et al. 2006), (Sombardier et al. 2010). Few options effective to control the pathogen in organic farming.
Need of a new approach to control the disease: Efficient Environment-friendly Low resistance potential Authorized in organic farming
What about Silicon???
Silicon as fertilizer Yield and quality Abiotic stress tolerance Beneficial in many plant/pathogen interactions Disease resistance 0 50 100 150 200 250 300 350 Published reports Prophylactic role First reports in Chinese and Japanese literature in the 1920 s First comprehensive report in USA by Wagner in 1940
SILICON (Si) Some studies have shown good results.. CUCUMBER: Powdery mildew (Sphaerotheca fuliginea) (Adatia & Besford, 1986) Pythium ultimum (Chérif & Bélanger, 1992) WHEAT: Powdery mildew (Blumeria graminis f. sp tritici) (Guével & al, 2007) RICE: Rice blast (Pyricularia oryzae Cavara) (Hayasaka & al., 2008) SOYBEAN: Phytophthora sojae (Guérin & al. 2014) Soybean rust (Phakopsora pachyrhizi) (Arsenault-Labrecque & al. 2012)
SILICON (Si) Prophylactic effects of Si : plant diseases Cucumber / Powdery mildew Control Si+ Lab. biocontrôle
Prophylactic effects of Si : plant diseases Wheat / Powdery mildew Control Si+ Lab. biocontrôle
Prophylactic effects of Si : plant diseases Soybean/Phytophthora sojae Control Si+ Lab. biocontrôle
Silicon(Si) Could its use fit in an integrated control program against strawberry powdery mildew?
SILICON (Si) Si prophylactic potential depends on Si uptake capacity of plants
SILICON (Si) Plants do not have the same Si uptake potential. Low accumulators Most dicotyledons (including Arabidopsis) 0,1 % dry weight Si Intermediate accumulators Dryland grasses Some dicots 1 % dry weight Si High accumulators Wetland grasses > 5 % dry weight Si (Marschner, 1995) (Jones et Handreck, 1967; Epstein, 1999)
Silicon transport in plants From the roots to the leaves Water flux cortex xylem Silicic acid Lsi1 Lsi2
SILICON (Si) Does strawberry have transporters in its roots? The power of genomics https://www.rosaceae.org/species/fragaria/fragaria_x_ananassa
ALIGNMENT
HYPOTHESIS
HYPOTHESIS Use of Si amendments can stimulate strawberry resistance to powdery mildew when grown in field or high tunnels. Si amendments can be an alternative to control strawberry powdery mildew and reduce the use of fungicides.
OBJECTIVES
OBJECTIVES Evaluation of Si amendments against strawberry powdery mildew SOILLESS CONDITIONS OPEN FIELD MANAGEMENT
OBJECTIVES For both objectives: Comparison of Si content (%) in leaves between different varieties. Evaluation of prophylactic effect of Si (powdery mildew incidence & yields).
METHODOLOGY
Methodology: Objective 1 (Soilless) Les Fraises de l île d Orléans, St-Laurent-de-l îled Orléans Cultivars (day neutral) : Charlotte, Seascape, Monterey, Albion, Amandine, Verity. Management: High tunnels, Peat substrate (Fafard et Frères) Si amendment: Potassium silicate (Kasil ) at a concentration of 1.7 mm Si
Methodology: Objective 2 Openfield Ferme François Gosselin, St-Laurent-de-l île-d Orléans Cultivars: Day neutral (Seascape, Albion) and Short day (Jewel). Management: Field, raised bed with plastic mulch. Si amendments: Wollastonite, 4 doses tested (0g, 12g, 24g, 36g per plant)
Methodology The variables measured for both objectives: Yield and fruit quality Silicon content in leaves (portable X-Ray Fluorescence spectrometer) Powdery mildew incidence: % of leaf area with mycelium (adaxial, abaxial, old and new leaf) and the % of infection on the fruits.
RESULTS
RESULTS: Objective 1 (soiless) Silicon content July September x 2 S. Ouellette, 2015
RESULTS: Objective 1 (soiless) Si treatment reduced infected fruits by more than 2.3 fold. Powdery mildew incidence
RESULTS: Objective 1 (soiless) Si treatment significantly increased the number of marketable fruits by 185%. Yield and fruit quality
Objective 2 (Openfield)
RESULTS: Objective 2 (field) Anticipated results: Significant Si absorption disease pressure / late infection Yield increase
CONCLUSION
In summary Strawberry powdery mildew is a problem: Yield loss Massive use of pesticides.. Loss of effectiveness of the main fungicides Very few options to control strawberry powdery mildew in organic farming
Results showed that it is possible to Delay infection and incidence of strawberry powdery mildew. yield. In conclusion, Si amendments could be an option to reduce the use of fungicides