Tomato Grafting Technique · 2014-07-29 · Grafting Basics "...fusion of plant parts . so that vascular continuity is established between them and the resulting genetically composite
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Tomato Grafting Technique Sushila Chaudhari 1 , David Suchoff 1 , Meagan Iott 2 , Emily Silverman 2 , Frank Louws 2 , Cary L. Rivard 3 Department of Horticulture Science, North Carolina State University 1 Department of Plant Pathology, North Carolina State University 2 Department of Horticulture, Kansas State University 3
Sushila Chaudhari1, David Suchoff1, 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 Basics
"...fusion of plant parts so that vascular continuity is established between them and the resulting genetically composite organism functions as a single plant." (Mudge, et al. 2009)
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Vegetable grafting is a old technology with a new technique. grafting of fruit and ornamental tree has been practiced for thousands of years. The first use of vegetable grafting was reported in early 1900s in Japan to manage a soil borne disease fusarium wilt on watermelons In grafting The belowground portion of a plant—the 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.
Scion - Above ground. provides desired fruits, flowers, etc.
Rootstock - Below ground. Imparts vigor, resistance to biotic/abiotic stress.
Grafting Basics
GRAFTED????
OR
NOT????
Benefits of Grafting
● Disease resistance against soilborne pathogens ● Grafting effective for overcoming abiotic
stresses ● Water and nutrient uptake ● Increase productivity
Grafting Worldwide
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However, first time vegetable grafting as commercial scale was adapted by Korea and Japan from the late 1950s to the early 1960s. Since then, vegetable grafting has become very popular in the World (Japan, Korea, Greece, Morocco, China, Israel, Italy, New Zealand, and Brunei) where intensive tomato production occurred. Currently, vegetable grafting is also gaining popularity in the United States as an alternative to methyl bromide (mandated by the U.S. Clean Air Act and the Montreal Protocol on Ozone Depleting Substances) to control soil-borne pests and diseases. Italy: 10-12 million tomato plants • Morocco: 20 million • Spain: <one million plants in 2000 to ~45 million plants in 2003-2004
Timeline
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To achieve a successful graft, make sure that the rootstock and the scion stems are the same diameter. Because different varieties require different germination periods. Stagger plantings is good option to to offset the effects of variable germination periods between rootstock and scion varieties. In many cases, rootstock varieties take two to five days longer to germinate than heirlooms8th edition of Plant Propagation.
First Step: Know disease and Chose Variety
●Disease Diagnosis
●Variety selection ●Scion
●Wanted fruit characteristics
●Rootstock ●Disease resistance
What diseases do I have?
What characteristics do I want in my tomatoes?
What diseases do I want to have resistance in?
Second Step: Supplies and Space
●Clean Space
●Razor blades
●Alcohol or other disinfectant
●Grafting Clips
●Healing Chamber
●Uniformity is key ●Germination period ●Substrate
●Rootstock and scion ●Numbers (at least 20%
more) ●Plastic trays
Third Step: Seeding / Transplant Production
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This is the first step of grafting is the sowing of rootstock and scion. As I mention earlier that to achieve a successful graft same stem diameter of root and scion is very important. So to get a idea of germination peroid of each root and scion, plant a few test seeds of each variety (both rootstock and scion) early in the year . Stagger the planting data of root and scion according to results. From our experience we mostly found that rootstock need 2-4 more days as compered to scion. Always use good sanitation practices and a sterile, lightweight potting mixture. Always plant at least 10 to 20 % more seedlings then you will need. This will help to choose same diameter plants at the time of grafting.
●Size:
●2-4 leaves ●1.5-2.0 mm stem
diameter ●Sorting
●Temperature can be manipulated to compensate for size differences.
●Timing is critical.
Fourth Step: Plants ready for grafting
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Tube grafting should be carried out when the seedlings have two to four true leaves and the stems are 1.5 to 2 millimeters in diameter (Figure 3) If for any reason either the rootstock or scion is much larger than its corresponding variety, decreasing the environmental temperature can help to slow the growth of the variety that may be ahead of schedule.
●Preparing for surgery…
●Make sure plants are not water or nutrient stressed.
●Have a clean working area. ●Disinfect hands, tools, and grafting clips.
●Carry out grafting indoors ●Be in close proximity to healing chamber.
Fifth step: Preparation for Grafting
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Sanitation is extremely important during grafting. Wash with anti-microbial soap, and use latex gloves and sterile tools to reduce the exposure of the plant to pathogenic bacteria, fungi, and viruses. Plants does not have stress Move plant to indoor 3-4 hrs earlier than grafting
Label scion and rootstock tray
Sixth Step: Performing Tube Grafting
Sixth Step: Performing Tube Grafting
●45 to 60 degree Angle of cut on rootstock
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To make a graft, a 45-60 degree angle cut make to below the cotelydene of rootstock, and sever the top half of a scion seedling from its bottom at a 45-degree angle (Figure 4).
●Clip attachment
Sixth Step: Performing Tube Grafting
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Attach the rootstock to the scion with a rubber or silicon clip
●45 to 60 degree Angle of
cut to scion
Sixth Step: Performing Tube Grafting
Presenter
Presentation Notes
To make a graft, a 45-60 degree angle cut make to below the cotelydene of rootstock, and sever the top half of a scion seedling from its bottom at a 45-degree angle (Figure 4).
Sixth Step: Performing Tube Grafting ●Provide good contact between rootstock and scion.
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Insert the scion into clip and make sure to provide a good contact between the rootstock and scion, so that their vascular tissues can easily grow together, forming a strong union for water and nutrient uptake.
Goal: During the healing process, the plant has to form callus tissue and reconnect vascular bundles within the stem.
Seventh Step: Life in the Chamber
Objectives of the healing chamber: Reducing water stress by slowing the transpirational stream. • Humidity (80 to 90%) • Light • Temperature (keep
temperature fairly constant and between 75 and 80 degrees F.
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Essential things for making Healing Chamber
• Plastic sheet: Maintain high humidity • Black cloth: Reduce light level
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Grafts should be left in the chamber for the first two to four days with absolutely no light and high humidity. the grafts will require two days at medium light and humidity levels before they can be moved into a low-humidity and high-light environment.
Type of Healing Chamber
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Excess water on the leaves can also physically pull the scion away from the rootstock. For this reason, do not mist grafts once they are in the chamber. While the grafts are still weak and healing, apply water from the bottom so that the grafts are not subjected to damage from overhead irrigation.
●Regulate light & humidity in the chamber
Type of Healing Chamber For small batch grafting
Type of Healing Chamber Inside Greenhouse
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After that, the graft is put into a healing chamber and allowed to reattach its vascular tissue under a pristine operating condition. These are pictures of some of the chambers that we have built on campus. Indoor and Outdoor. Overhead tarp
Eight Step: Life in the Greenhouse
• 7-10 days in the Greenhouse
• Hardening off • Overhead Watering • The Clip • Transportation
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During this period., it is best to water from the bottom to prevent any physical damage to the grafts while the graft union is still weak. Careful overhead watering is possible as long as the seedlings are not exposed to high water pressure that could separate a scion from its rootstock. As the grafted transplants develop, the grafting clip will expand with the growing stem, and eventually fall off (Figure 7).
Ninth Step: Life on the Farm
Planting Depth Suckering
1. During the transplanting into field, the graft union is well above the soil line
2. Suckers should remove at time
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During the transplanting into field, the graft union is well above the soil line. If ti would be below the soil then susceptible scion tissue may be exposed to soilborne pathogens below ground. Field should also monitor for suckers. Suckers are branches that form below the graft union. By removing these branches, the scion will be provided with more water and nutrients and increase production of the desired high-quality fruit.
Very Important: 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 • Insufficient light