Netting Research Update Lee Kalcsits, Associate Professor WSU Tree - - PowerPoint PPT Presentation

Netting Research Update

Lee Kalcsits, Associate Professor WSU Tree Fruit Research and Extension Center Department of Horticulture Wenatchee, WA APAL Webinar July 23, 2020

Overview

Example: Protective Netting in Fruit Production

Hail/Sunburn Environment Fruit Quality Physiology Design Considerations

1% 3% 80% 10 20 30 40 50 60 70 80 90 Exclusion net Drape net Control Fruit damaged by hail (%) Treatment Photo credit: S. Musacchi

• Protective netting also acts as a physical barrier against hail
• Hail damage reduced from 80% in the control to 3% and 1% under

drape net and exclusion net respectively (Schmidt, 2014)

Protective Netting in Fruit Production

Reducing Hail Damage

Protective Netting in Fruit Production

Reducing Hail Damage

(Racsko and Schrader, 2012) (Racsko and Schrader, 2012)

Protective Netting in Fruit Production

Apple Sunburn

Protective Netting in Fruit Production

Apple Sunburn Management

• The largest contributor to fruit

losses in Washington State

• Approximately 10%

Protective Netting in Fruit Production

Changes in Sunburn Risk

Days per year above 95°F

5 50 100 200 PNW = 25 -> 60 NE = 2 -> 30 MW = 3 -> 46 SA = 7 -> 52 AUS = 11 -> 54

• S. Europe = 0 -> 27

Overview

Protective Netting in Fruit Production

Hail/Sunburn Environment Fruit Quality Physiology Design Considerations

Light Intensity (umol m-2 s-1) Wind Speed (km h-1) Control 1804 a 6.03 a Blue 1404 b 3.76 b Pearl 1459 b 3.96 b Red 1355 b 3.64 b

Table 1. Mean light intensity and wind speed for Blue, Pearl and Red netting compared to an uncovered control (84 days). Letters indicate significant difference determined by Tukey’s HSD test. 0.5 1 1.5 2

2.5 3 3.5 4 4.5 5

10-May 29-Jun 18-Aug 7-Oct

Wnid Speed (km h-1) Control Pearl Blue Red

Protective Netting in Fruit Production

Light Intensity and Wind Speed

Light Scattering

Protective Netting in Fruit Production

Diffuse Lighting

Overview

Protective Netting in Fruit Production

Hail/Sunburn Environment Fruit Quality Physiology Design Considerations

Red Blue Pearl Control

High Grade Reduced-Grade Cull

Protective Netting in Fruit Production

Fruit Sunburn (Honeycrisp) - 2015

2015 2016 Control 231 a 366 a Pearl 274 c 394 b Blue 252 b 388 b Red 260 bc 386 b Average fruit size (g) for fruit harvested from under pearl, blue and pearl netting compared to an uncovered control

Protective Netting in Fruit Production

Fruit Size

SSC (°Brix) Control 15.0 a Pearl 14.7 ab Blue 14.5 b Red 14.5 b

• When fruit size is

accounted for, there are more sugars per fruit netting compared to the uncovered control.

• Color development

was better in 2015 compared to 2016. Uncovered trees had slightly better color in 2015 compared to netted trees.

2015 2016 Control 2.77 a 2.30 a Netted 2.52 b 2.25 a Fruit red color development in Honeycrisp apple in 2015 and 2016 under netting compared to an uncovered control. 2 = 50% red color. Fruit red color development and soluble sugars content (Brix) in Honeycrisp apple under pearl, blue and red netting compared to an uncovered control. 2 = 50% red color.

Protective Netting in Fruit Production

Fruit Quality

Overview

Protective Netting in Fruit Production

Hail/Sunburn Environment Fruit Quality Physiology Design Considerations

Protective Netting in Fruit Production

Physiology

2 4 6 8 10 12 14

Control Netting

Shoot Growth (Inches)

Protective Netting in Fruit Production

Improving canopy in-fill

0.1 0.2 0.3 0.4 0.5 0.6 Quantum Yield of Photosystem II (P) Honeycrisp 5 10 15 20 25 Net CO2 Exchange (µmol m-2 s-

1)

Honeycrisp

Light Use Efficiency Photosynthesis

Protective Netting in Fruit Production

Sap Flow Under Netting

5 10 15 28-Jul 29-Jul 30-Jul 31-Jul 1-Aug Cummulative evaporation (mm d-1) Date

Control

100 200 300 400 500 Tree Water Use (mL H2O hr-1)

Time of Day

Netting Control

Protective Netting in Fruit Production

Sap Flow Under Netting

Overview

Protective Netting in Fruit Production

Hail/Sunburn Environment Fruit Quality Physiology Design Considerations

• Most common netting structure used by growers in WA

Protective Netting in Fruit Production

Continuous Over-the-Top Structure

Exclusion netting (both top and sides)

• Exclusion netting offers the most protection and can be used on sites

where wind damage is a higher risk

Protective Netting in Fruit Production

Exclusion Netting

• Most effective in a north-south tree row orientation; protection to the

west side of the tree that is exposed to damaging solar radiation in the afternoon

Protective Netting in Fruit Production

Louvre Netting

Protective Netting in Fruit Production

Drape Netting

• Easiest to deploy
• Lowest cost
• Most difficult to work

under

• No superstructure

Protective Netting in Fruit Production

Considerations

• Labor for deployment and retraction
• Post-bloom and post-harvest
• Design – Retrofit or in new orchards
• Retrofitting is much more expensive

and labor intensive…plan ahead

• Engineering
• Essential!

Protective Netting in Fruit Production

Summary

Hail Protection Reduced Sunburn Increased Canopy Infill Reduced water-use Improve sizing and quality Slight reductions in color development Costs Labor to deploy and retract Disease pressure?? Positives Negatives

Questions?

Kalcsits Lab Crew - 2018

Back Row (L to R): Lee Kalcsits, Ryan Mullin, Jack Gavin, Giverson Mupambi, Chloe Smythman, Hector Camargo-Alvarez Front row (L to R): Erica Casagrande Biasuz, Brenda Castaneda, Michelle Reid, Katie Mullin, Sumyya Waliullah, Nadia Valverdi, Raquel Gomez