Particle Film Technology in Agriculture to Reduce Heat Stress and Suppress Disease Michael Glenn Soil Scientist

Reflective surfaces are common plant adaptation Plants use pubescence and cuticular waxes to reduce environmental stresses Particle film technology builds on this strategy of a reflective plant surface

Particle Film of processed kaolin on the surface of an apple leaf

Particle Film on the underside of an apple leaf. The stomates are not blocked.

Particle film materials can be applied with conventional spray equipment. Film development requires multiple applications First Spray Second Spray Third Spray

The reflective, particle film reduces the temperature of fruit and leaves by reflecting infrared radiation (heat) The apple on the left has a particle film, the apple on the right is untreated. This is an infrared image of the temperatures of the two fruit. The untreated fruit has a severe hot spot developing but the particle film treated fruit is much cooler

Reducing the heat load on fruit reduces sunburn damage and increases net dollar return to the grower

Whole tree photosynthesis is measured with clear, mylar chambers. Studies demonstrate that the application of a particle film increases: – Photosynthesis – Fruit size – Red color

Surround-WP reduced fruit cracking in Stayman apple Untreated had 32% cracking Particle film treated had 22% cracking A 10 % reduction in cracking results in $100s of dollars in net return to the grower

Control Conventional Surround WP Lime Sulfur + Wettable Sulfur Surround WP + Lime Sulfur + Wettable Sulfur Particle film materials together with sulfur minerals provide excellent suppression of apple scab and powdery mildew Surround WP, wettable sulfur and lime sulfur are listed as organically approved apple scab apple scab powdery mildew

Particle film materials control Fabraea Leafspot in pear The tree in the foreground is defoliated by Fabraea leafspot disease

Implications of Particle Film Technology in Tree Fruit Production Reduced sunburn and fruit cracking Increased crop loads Improved fruit quality Multi-functional role of horticultural benefits as well as disease control High degree of insect suppression (See Dr. Puterkas web site)