12/6/2012
Vegetable Grafting: An Old Technology with a New Technique
The belowground portion of a plant—the Tomato Grafting Technique rootstock— is chosen for its genetic ability to resist or tolerate soilborne disease. The above‐ground portion of the plant—the scion—is chosen based on fruit quality. Sushila Chaudhari1, Meagan Iott2, Emily Silverman2, Frank Louws2, Cary L. Rivard3 Department of Horticulture Science, North Carolina State University1 Department of Plant Pathology, North Carolina State University2 Department of Horticulture, Kansas State University3
Grafting Worldwide Benefits of Grafting
• Disease resistance against soilborne pathogens • Grafting effective overcome abiotic stresses • Water and nutrient uptake • Increase productivity
Vegetable Grafting Grafting Information
Cucurbits (cucumber, watermelon and other melons) Hole‐insertion grafting, One cotyledon grafting, and Approach grafting http://cals.arizona.edu/grafting/howto/cucurbits/gra fting_methods Solaneceous ( Tomato, eggplant and pepper etc.)
http://www.youtube.com/watch?v=Q5QzDTA6J5Q
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Grafting Information Grafting Information
http://www4.ncsu.edu/~clrivard/TubeGraftingTechnique.pdf
Disclaimer Disease and Variety
• No Recipe for Success • Disease Diagnosis What diseases • Principles do I have? • Variety selection – Production – Scion What – Uniformity • Wanted fruit characteristics characteristics do I want in – Water Stress my tomatoes? – Rootstock – Sanitation • Disease resistance What diseases do I want to – Re‐acclimation have resistance in?
Supplies and Space
• Clean Space
• Razor blades
• Alcohol or other disinfectant
• Grafting Clips
• Healing Chamber
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Propagation Costs Tomato Grafting Techniques • Proportion of added costs
– e.g. seed costs (%) = (SEEDgraft ‐ SEEDnon) / (TOTALgraft ‐ TOTALnon) Cleft Grafting Tongue Approach Grafting
Tube‐grafting
$0.46 / plant $0.74 / plant = Added cost
(Rivard et al., 2010)
Tube Grafting Timeline
• The advent of “tube‐grafting” or “Japanese top‐grafting” has become the most popular for tomato.
– Seedlings are grafted at 2‐4 leaf stage.
– High Throughput
• A person can make ~ 1000 grafts/day
• Grafting robots can make 700 grafts/hr.
Seeding / Transplant Production Tube Grafting Technique
• Uniformity is key • Size: – Germination period – 2‐4 leaves – Substrate – 1.5‐2.0 mm stem diameter – Transplanting / Sowing – Sorting • Temperature can be • Rootstock and scion manipulated to • Numbers compensate for size differences. • Plastic trays • Timing is critical.
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Tube Grafting Technique Tube Grafting Technique
• Preparing for surgery… • Angle of cut – Make sure plants are not water or nutrient stressed. • Clip attachment – Have a clean working area. • Disinfect hands, tools, and grafting clips. • Scion insertion – Carry out grafting indoors • Provide good contact – Be in close proximity to healing chamber. between the rootstock and the scion.
Tube Grafting Technique Tube Grafting Technique
• Angle of cut • Angle of cut to rootstock
• Clip attachment • Clip attachment • Angle of cut to scion • Scion insertion • Scion insertion • Provide good contact between the rootstock • Provide good contact and the scion. between the rootstock and the scion.
Tube Grafting Technique Tube Grafting Technique
• Angle of cut
• Clip attachment
• Scion insertion
• Provide good contact between the rootstock and the scion.
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Tube Grafting Technique Tube Grafting Technique
Tube Grafting Technique Tube Grafting Technique
Timeline Life in the Chamber
– During the healing process, the plant has to form callus tissue and reconnect vascular bundles within the stem.
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Life in the Chamber Life in the Chamber
• Objectives of the • Regulate humidity healing chamber – Reducing water stress – Cool-water vaporizers by slowing the – Humidifiers transpirational stream. – Passive humidifiers • Humidity • Light – No warm-water vaporizers • Temperature – Overhead watering – Keep temperature fairly constant and between 75 and 80 degrees F. Small cool-mist vaporizer (~$40). Note: 1.5” PVC connectors to direct water vapor
• Regulate light & humidity in the chamber
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Life in the Greenhouse
• 7‐10 days in the Greenhouse – Hardening off
– Overhead Watering
– The Clip
– Transportation
Life on the Farm Life on the Farm
Planting Depth Suckering NON-GRAFTED MAXIFORT
Life on the Farm Reason for Graft Failure
• Seedlings are unhealthy and improperly matched in diameter • Small seedling grafting • Insufficient sanitation • Improper management of post‐grafting environment • High temperature • High humidity • Direct overhead watering • Excessive light Twin leader for Twin leader for stake- • Insufficient light European string trellis and-weave Young et. al. 2009
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Sanitation Review
During Grafting and Healing Other Areas of Concern:
• Contamination is common during • Saving seeds? • Uniformity of seedlings grafting‐ vulnerable plants – Sanitize seeds in bleach to • Use alcohol to wipe down grafting prevent seed borne • Timing pathogens after seed area before and after use extraction • Dip or wipe cutting utensils in • Organic production‐ soil with • Patience alcohol often damping off pathogens‐ • Bleach grafting area after use Rhizoctoni and Phythium sp. • Sanitation • Bleach humidifiers in between uses – Steam soil if possible to reduce algae build up – Monitor and remove infected • Careful observation • Clean healing chamber between plants uses • Extended periods of leaf wetness can lead to fungal problems such • Water management • Soak used grafting clips in bleach as leaf mold or powdery mildew solution and rinse repeatedly – Adjust leaf wetness‐ monitor • Cultural Management • Bleach and rinse propagation trays humidity and look out for if reusing trays water droplets on foliage
Important links for Grafting Information: Questions???
Informational Resources:
1. http://loghouseplants.com/plants/library/grafting/ 2. http://www.hort.uconn.edu/ipm/greenhs/htms/Tomgraft.htm 3. http://www.deruiterusa.com/products/rootstock/root2.html 4. http://oardc.osu.edu/graftingtomato/graft.htm 5. http://cals.arizona.edu/grafting/home
Grafting Supplies Resources:
1. http://www.johnnyseeds.com/c‐278‐grafting‐clips.aspx 2. http://www.dpalmerseed.com/ 3. http://www.rijkzwaanusa.com/ 4. http://www.neseed.com/
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