Induced-Resistance Agents, Silicon Fertilizers, Synthetic Fungicides

Summary: Induced-resistance agents, silicon fertilizers and both together do less well than, as well as and better than synthetic fungicides such as penconazole.

apple (Malus spp.) with symptoms of apple scab disease caused by Venturia inaequalis: University of Georgia Plant Pathology, University of Georgia, Bugwood.org, CC BY 3.0 United States, via Forestry Images

Field trials applied apple and pear scab-controlling silicon (Si) fertilizers, induced-resistance (IR) agents and their combination comparatively to conventional synthetic fungicides, according to an article in Arboriculture & Urban Forestry September 2018.

Field trials by Glynn C. Percival of R.A. Bartlett Tree Research Laboratory broached apple and pear scab because of reduced aesthetics, fruit quality and marketable yields. They commenced with scab fungal symptoms of olive-green spots on leaves or petioles initially and of premature, yellowed leaf drop and deformed, immature fruit drop subsequently. The article Evaluation of Silicon Fertilizers and a Resistance Inducing Agent for Control of Apple and Pear Scab under Field Conditions describes alternatives to synthetic fungicides.

Silicon fertilizers emphasize drought, heavy metal toxicity, lodging and salt resistance; growth; soil penetration by roots; soil-borne and foliar fungal pathogen control; transpiration reduction; and yield.

Induced resistance by fungi-attenuating or weakening biological agents and inorganic potassium and phosphate salt, low-molecular-weight protein and unsaturated fatty acid chemical agents fortify plant defense mechanisms.

The two-year fertilizer- and water-free field trial sites got deltamethrin insecticide treatments every two months from May 2014 to September 2015 and glyphosate weed control treatments. Malus apple and Pyrus communis trial sites had induced-resistance and silicon treatments at bud break, green cluster, 90 percent petal fall and early fruitlet growth stages. Induced-resistance and silicon-nutrition treatments involved 60 observations each of one IR compound, one fungicide and four silicon fertilizers sprayed four times in 10 randomized complete blocks.

Measurements of leaf chlorophyll from comparable-aged leaves at midpoints near their main veins juxtaposed two fully expanded, mature leaves each from crown tops, centers and bases.

The 0.75-hectare (1.85-acre) apple and 0.90-hectare (2.22-acre) peach sites kept aesthetic, defoliated, discolored and yellowed leaf and lesion and percent infected surface fruit scab severity ratings.

Scab outbreaks led to Golden Delicious' respective 4.8 and 5.0 severity ratings Sept. 28, 2014, and Sept. 28, 2015, and to Williams' 3.4 rating both times. Fruit yield and leaf chlorophyll content measure penconazole synthetic fungicide and polyether-modified trisiloxane and salicyladehde as efficacious scab-protectant compounds that minimize fruit and leaf scab severity. The IR agent salicylaldehyde and the Fossil, Rigel, Sil-MATRIX and Sirius silicon fertilizers respectively netted lowest scab-protective compound and highest fruit and leaf silicon content ratings.

Lawrence Datnoff in Baton Rouge, Louisiana, and Renata Resende in Minas Gerais, Brazil, observed silicon nutrition-obtained fungal-resistant barley, corn, grape, peach, rice, rye, strawberry and wheat.

Tsuyoshi Hayasaka in Tsuruoka, Japan, and Sang Gyu Kim in Suwon, South Korea, propose scab-resistant mechanical or physical barriers that cell walls promote through silicon nutrition.

Yanchun Liang and Wanchun Sun in Beijing, China, and Fabríco Á. Rodrigues in Minas Gerais, Brazil, queue up pathogen-resistant silicon-induced lignin, peroxidase, phenolic-compound and phytoalexin accumulation. Development of triazole-insensitive strains results in alternative scab management treatments that replace anti-fungal scab-resistant penconazole schedules at bud break, green cluster, petal fall and early fruitlet. Phenol-based salicylic acid compound and derivative-composed silicon fertilizers and IR agents synthesize bacteria-, fungus-, virus-resistant anti-digestive, anti-microbial, anti-nutritive toxins scarcely toxic to aquatic invertebrates and mammals.

Induced-resistance agents teamed with silicon fertilizers turn alkaloid, phenolic and terpenoid synthesis and cell wall silification into ecosystem-safe, synthetic-competitive fungal pathogen control and low ecosystem toxicity.

pear (Pyrus spp.) fruit with symptoms of pear scab disease caused by Venturia pirina: Howard F. Schwartz, Colorado State University, Bugwood.org, CC BY 3.0 United States, via Forestry Images

Acknowledgment

My special thanks to:
talented artists and photographers/concerned organizations who make their fine images available on the internet;
University of Illinois at Urbana-Champaign for superior on-campus and on-line resources.

Image credits:

apple (Malus spp.) with symptoms of apple scab disease caused by Venturia inaequalis: University of Georgia Plant Pathology, University of Georgia, Bugwood.org, CC BY 3.0 United States, via Forestry Images @ https://www.forestryimages.org/browse/detail.cfm?imgnum=1496022

pear (Pyrus spp.) fruit with symptoms of pear scab disease caused by Venturia pirina: Howard F. Schwartz, Colorado State University, Bugwood.org, CC BY 3.0 United States, via Forestry Images @ https://www.forestryimages.org/browse/detail.cfm?imgnum=5358918

For further information:

Datnoff, L.E.; F.Á. Rodrigues; and K.W. Seebold. 2007. "Silicon and Plant Disease." Pp. 233-246. In: L.E. Datnoff, W.H. Elmer and D.M. Huber, eds., Mineral Nutrition and Plant Disease. St. Paul MN: The American Phytopathological Society.

Gilman, Ed. 2011. An Illustrated Guide to Pruning. Third Edition. Boston MA: Cengage.

Hayasaka, T.; H. Fujii; and K. Ishiguro. 2008. "The Role of Silicon in Preventing Appressorial Penetration by the Rice Blast Fungus." Phytopathology 98: 1038-1044.

Hayes, Ed. 2001. Evaluating Tree Defects. Revised, Special Edition. Rochester MN: Safe Trees.

Kim, S.G.; K.W. Kim; E.W. Park; and D. Choi. 2002. "Silicon-Induced Cell Wall Fortification of Rice Leaves: A Possible Cellular Mechanism of Enhanced Host Resistance to Blast." Phytopathology 92: 1095-1103.

Liang, Y.C.; W.C. Sun; J. Si; and V. Römheld. 2005. "Effect of Foliar- and Root-Applied Silicon on the Enhancement of Induced Resistance in Cucumis sativus to Powdery Mildew." Plant Pathology 54: 678-685.

Marriner, Derdriu. 26 August 2018. "Nursery Production Systems for Successful Urban Tree Plantings." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/08/nursery-production-systems-for.html

Marriner, Derdriu. 29 July 2018. "Tree Roots Branch in Fabric Containers But Circle and Girdle Plastic." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/07/tree-roots-branch-in-fabric-containers.html

Marriner, Derdriu. 30 June 2018. "Wood Decay Fungi Management of Terminal Urban Pathogens." Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2018/06/wood-decay-fungi-management-of-terminal.html

Marriner, Derdriu. 27 May 2018. "Downtown Commercial Streetscape Tree Populations in Toronto, Canada." Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/05/downtown-commercial-streetscape-tree.html

Marriner, Derdriu. 28 April 2018. “Mushroom-Forming and Non-Mushroom-Forming Fungal Life Cycle Traits.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2018/04/mushroom-forming-and-non-mushroom.html

Marriner, Derdriu. 17 March 2018. “Emerald Ash Borer Rapid Response Community Preparedness Project.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2018/03/emerald-ash-borer-rapid-response.html

Marriner, Derdriu. 17 February 2018. “Tree Retention by Arborists for Wildlife Habitat Friendly Tree Care.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2018/02/tree-retention-by-arborists-for.html

Marriner, Derdriu. 14 January 2018. “Integrated Vegetation Management Study in North and South Yukon, Canada.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2018/01/integrated-vegetation-management-study.html

Marriner, Derdriu. 9 December 2017. “Tree Inventories: Preemptive and Proactive or Piecemeal and Reactive.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/12/tree-inventories-preemptive-and.html

Marriner, Derdriu. 25 November 2017. “Chlorantraniliprole Reduced-Risk Insecticides Get Leaf-Eaters Not Bees.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/11/chlorantraniliprole-reduced-risk.html

Marriner, Derdriu. 28 October 2017. “Palm Plant Health Care: Abiotic, Biotic Stress Culture and Management.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/10/palm-plant-health-care-abiotic-biotic.html

Marriner, Derdriu. 16 September 2017. “Predawn Leaf Water Potentials Indicate Crown Dieback and Water Status.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/09/predawn-leaf-water-potentials-indicate.html

Marriner, Derdriu. 19 August 2017. “Palm Tree Identification and Pruning of Native and Naturalizable Palms.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/08/palm-tree-identification-and-pruning-of.html

Marriner, Derdriu. 22 July 2017. “Commonly Planted, Potentially Phytoremediating Street Tree Species.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/07/commonly-planted-potentially.html

Marriner, Derdriu. 17 June 2017. “Root Loss From Root Pruning and Root Shaving of Stem-Girdling Roots.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/06/root-loss-from-root-pruning-and-root.html

Marriner, Derdriu. 27 May 2017. “Age and Canopy Area Cost Less and Tell More in Urban Tree Inventories.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/05/age-and-canopy-area-cost-less-and-tell.html

Marriner, Derdriu. 22 April 2017. “Urban Root Management: Big Infrastructure, Small Space, Stressed Roots.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/04/urban-root-management-big.html

Marriner, Derdriu. 12 March 2017. “Flexural Elasticity Modulus: Trees and Watersprouts Bend or Break.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2017/03/flexural-elasticity-modulus-trees-and.html

Marriner, Derdriu. 18 February 2017. “Plant Health Care Diagnostics When Plants and Places Wrong One Another.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/02/plant-health-care-diagnostics-when.html

Marriner, Derdriu. 14 January 2017. “Tree Fertilization for Fine Root Growth and Whole Root System Effects.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2017/01/tree-fertilization-for-fine-root-growth.html

Marriner, Derdriu. 17 December 2016. “Abiotic and Biotic Stress in Low Maintenance Tree Health Care Programs.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/12/abiotic-and-biotic-stress-in-low.html

Marriner, Derdriu. 19 November 2016. “Organic Amendments to Compacted Degraded Urban Highway Roadsides.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/11/organic-amendments-to-compacted.html

Marriner, Derdriu. 15 October 2016. “Tree Protection Zones by Arborists for All Construction Project Phases.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/10/tree-protection-zones-by-arborists-for.html

Marriner, Derdriu. 17 September 2016. “Stormwater Runoff Landscaping With Urban Canopy Cover and Groundcover.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/09/stormwater-runoff-landscaping-with.html

Marriner, Derdriu. 13 August 2016. “Changing Places: Tree Nutrient Movement Down, Tree Water Movement Up.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/08/changing-places-tree-nutrient-movement.html

Marriner, Derdriu. 16 July 2016. “Treated or Untreated Oriental Bittersweet Vine Management Cut-Stumping.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/07/treated-or-untreated-oriental.html

Marriner, Derdriu. 18 June 2016. “Tree Injection Site Procedures: Manufacturer's Instructions and Labels.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/06/tree-injection-site-procedures.html

Marriner, Derdriu. 22 May 2016. “Electrical Utility Area Temperate Urban Street Trees: Pruned Regrowth.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2016/05/electrical-utility-area-temperate-urban.html

Marriner, Derdriu. 16 April 2016. “Tree Injection Methods: Treatment Option in Integrated Pest Management.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/04/tree-injection-methods-treatment-option.html

Marriner, Derdriu. 6 March 2016. “Bare-Rooted Ornamental Urban Transplants: Amendments Against Mortality.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2016/03/bare-rooted-ornamental-urban.html

Marriner, Derdriu. 28 February 2016. “Bark Protective Survival Mechanisms Foil Deprivation, Injury, Invasion.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2016/02/bark-protective-survival-mechanisms.html

Marriner, Derdriu. 23 January 2016. "LITA Model: Linear Index of Tree Appraisal of Large Urban Swedish Trees." Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2016/01/lita-model-linear-index-of-tree.html

Marriner, Derdriu. 19 December 2015. “Tree Lightning Protection Systems: Site, Soil, Species True Designs.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/12/tree-lightning-protection-systems-site.html

Marriner, Derdriu. 24 October 2015. “Tree Lightning Protection Systems Tailored to Sites, Soils, Species.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/10/tree-lightning-protection-systems.html

Marriner, Derdriu. 15 August 2015. “Tree Friendly Urban Soil Management: Amend, Fertilize, Mulch, Till!” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/08/tree-friendly-urban-soil-management.html

Marriner, Derdriu. 13 June 2015. “Tree Friendly Urban Soil Management: Assemble, Assess, Assist, Astound.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/06/tree-friendly-urban-soil-management.html

Marriner, Derdriu. 18 April 2015. “Tree Wound Responses: Healthy Wound Closures by Callus and Woundwood.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2015/04/tree-wound-responses-healthy-wound.html

Marriner, Derdriu. 15 February 2015. “Urban Forest Maintenance and Non-Maintenance Costs and Benefits.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2015/02/urban-forest-maintenance-and-non.html

Marriner, Derdriu. 13 December 2014. “Tree Dwelling Symbionts: Dodder, Lichen, Mistletoe, Moss and Woe-Vine.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/12/tree-dwelling-symbionts-dodder-lichen.html

Marriner, Derdriu. 18 October 2014. “Tree Cable Installation Systems Lessen Target Impact From Tree Failure.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/10/tree-cable-installation-systems-lessen.html

Marriner, Derdriu. 16 August 2014. “Flood Tolerant Trees in Worst-Case Floodplain and Urbanized Scenarios.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/08/flood-tolerant-trees-in-worst-case.html

Marriner, Derdriu. 14 June 2014. “Integrated Vegetation Management of Plants in Utility Rights-of-Way.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/06/integrated-vegetation-management-of.html

Marriner, Derdriu. 12 April 2014. “Tree Twig Identification: Buds, Bundle Scars, Leaf Drops, Leaf Scars.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/04/tree-twig-identification-buds-bundle.html

Marriner, Derdriu. 15 February 2014. “Tree Twig Anatomy: Ecosystem Stress, Growth Rates, Winter Identification.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2014/02/tree-twig-anatomy-ecosystem-stress.html

Marriner, Derdriu. 14 December 2013. “Community and Tree Safety Awareness During Line- and Road-Clearances.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/12/community-and-tree-safety-awareness.html

Marriner, Derdriu. 13 October 2013. “Chain-Saw Gear and Tree Work Related Personal Protective Equipment.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2013/10/chain-saw-gear-and-tree-work-related.html

Marriner, Derdriu. 12 October 2013. “Storm Damaged Tree Clearances: Matched Teamwork of People to Equipment.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/10/storm-damaged-tree-clearances-matched.html

Marriner, Derdriu. 17 August 2013. “Storm Induced Tree Damage Assessments: Pre-Storm Planned Preparedness.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/08/storm-induced-tree-damage-assessments.html

Marriner, Derdriu. 15 June 2013. “Storm Induced Tree Failures From Heavy Tree Weights and Weather Loads.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/06/storm-induced-tree-failures-from-heavy.html

Marriner, Derdriu. 13 April 2013. “Urban Tree Root Management Concerns: Defects, Digs, Dirt, Disturbance.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/04/urban-tree-root-management-concerns.html

Marriner, Derdriu. 16 February 2013. “Tree Friendly Beneficial Soil Microbes: Inoculations and Occurrences.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2013/02/tree-friendly-beneficial-soil-microbes.html

Marriner, Derdriu. 15 December 2012. “Healthy Urban Tree Root Crown Balances: Soil Properties, Soil Volumes.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/12/healthy-urban-tree-root-crown-balances.html

Marriner, Derdriu. 13 October 2012. “Tree Adaptive Growth: Tree Risk Assessment of Tree Failure, Tree Strength.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/10/tree-adaptive-growth-tree-risk.html

Marriner, Derdriu. 11 August 2012. “Tree Risk Assessment Mitigation Reports: Tree Removal, Tree Retention?” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/08/tree-risk-assessment-mitigation-reports.html

Marriner, Derdriu. 16 June 2012. “Internally Stressed, Response Growing, Wind Loaded Tree Strength.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/06/internally-stressed-response-growing.html

Marriner, Derdriu. 14 April 2012. “Three Tree Risk Assessment Levels: Limited Visual, Basic and Advanced.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/04/three-tree-risk-assessment-levels.html

Marriner, Derdriu. 19 February 2012. “Qualitative Tree Risk Assessment: Risk Ratings for Targets and Trees.” Earth and Space News. Sunday.
Available @ https://earth-and-space-news.blogspot.com/2012/02/qualitative-tree-risk-assessment-risk.html

Marriner, Derdriu. 18 February 2012. “Qualitative Tree Risk Assessment: Falling Trees Impacting Targets.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2012/02/qualitative-tree-risk-assessment.html

Marriner, Derdriu. 10 December 2011. “Tree Risk Assessment: Tree Failures From Defects and From Wind Loads.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/12/tree-risk-assessment-tree-failures-from.html

Marriner, Derdriu. 15 October 2011. “Five Tree Felling Plan Steps for Successful Removals and Worker Safety.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/10/five-tree-felling-plan-steps-for.html

Marriner, Derdriu. 13 August 2011. “Natives and Non-Natives as Successfully Urbanized Plant Species.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/08/natives-and-non-natives-as-successfully.html

Marriner, Derdriu. 11 June 2011. “Tree Ring Patterns for Ecosystem Ages, Dates, Health and Stress.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/06/tree-ring-patterns-for-ecosystem-ages.html

Marriner, Derdriu. 9 April 2011. “Benignly Ugly Tree Disorders: Oak Galls, Powdery Mildew, Sooty Mold, Tar Spot.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/04/benignly-ugly-tree-disorders-oak-galls.html

Marriner, Derdriu. 12 February 2011. “Tree Load Can Turn Tree Health Into Tree Failure or Tree Fatigue.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2011/02/tree-load-can-turn-tree-health-into.html

Marriner, Derdriu. 11 December 2010. “Tree Electrical Safety Knowledge, Precautions, Risks and Standards.” Earth and Space News. Saturday.
Available @ https://earth-and-space-news.blogspot.com/2010/12/tree-electrical-safety-knowledge.html

Percival, Glynn C. September 2018. "Evaluation of Silicon Fertilizers and a Resistance Inducing Agent for Control of Apple and Pear Scab under Field Conditions." Arboriculture & Urban Forestry 44(5): 205-214.

Resende. R.S.; F.Á. Rodrigues; R.V. Costa; and D.D. Silva. 2012. "Silicon and Fungicide Effects on Anthracnose in Moderately Resistant and Susceptible Sorghum Lines." Journal of Phytopathology 161(1): 11-17.

Sun, W.C.; J. Zhang; Q.H. Fan; G.F. Xu; and Z.I. Li. 2010. "Silicon-Enhanced Resistance to Rice Blast Is Attributed to Silicon-Mediated Defense Resistance and Its Role as Physical Barrier." European Journal Plant Pathology 128: 39-49.