Tomato Grafting: Developing Grower Recommendations for the Great Plains and Enhancing Our Understanding of the “Rhizobiome”

Tomato Grafting: Developing Grower Recommendations for the Great Plains and Enhancing Our Understanding of the “Rhizobiome”

Summary

This project was very successful in 2014 and all of our major performance targets were obtained, if not exceeded as they were described in the proposal. We successfully conducted eight research trials, five of which were on commercial farms. We also carried out exhaustive greenhouse studies during spring 2014, which are the basis for Lani Meyer’s M.S. thesis (expected graduation Aug 2015). We were very successful at communicating the results of our work to scientific and grower audiences. Education efforts included two hands-on grafting workshops, a “twilight tour”, and the grafting clinic, which was not an expected activity in the original proposal (described below). All of these venues were very successful at making changes in knowledge and behavior of growers.

Objectives/Performance Targets

The objectives of this project are (1) to identify rootstocks that improve productivity and reduce disease losses in the Great Plains through a series of on-farm and university research trials, (2) to determine optimum grafting/healing conditions that reduce risk of crop failure and increases the successful implementation of grafting for small-scale growers, (3) evaluate the effects of rootstocks on rhizosphere microbial communities; and (4) disseminate grafted propagation methods as well as the results of our research through an integrated extension program. We will perform a series of replicated field studies including at least two on-farm trials per year that evaluate tomato rootstocks for their performance in regards to soilborne disease, crop yield, and marketability. Specific outputs include (1) Extension publications, field tours, web materials, videos, and hands-on workshops; (2) Research journal publications, presentations, and teaching materials. Short-term outcomes include (1) Increased grower knowledge for grafting implementation; (2) Increased scientific community understanding of rhizobiome interactions. Mid- and Long-term outcomes include: (1) Changes in grower behavior related to propagation of grafted plants and rootstock selection; (2) Increased local availability of grafted plants; (3) Further scientific exploration of grafting and rhizobiome interactions, in support of fuller understanding of mechanisms of disease resistance and increased vigor. This proposal builds on a project that is supported by the Ceres Trust Organic Research Initiative.

Accomplishments/Milestones

• Performed five on-farm high tunnel and/or open-field research trials that evaluated numerous rootstocks for growers in the North Central Region at commercial farms.
• Performed three high tunnel and/or open-field research trials that evaluated numerous rootstocks for growers in the North Central Region at KSU research stations.
• All data from research trials was analyzed and presented at venues including:
  • Summer on-farm twilight tour in Kansas City, KS
  • ASHS conference in Orlando, FL
  • National Grafting Symposium in Savannah, GA
  • Horticulture Sciences Day at Johnson County Community College (Overland Park, KS)
  • Great Plains Growers Conference in St. Joseph, MO
  • Two grafting workshops delivered locally
  • OHREC field day
• Sampled roots at OHREC, Common Harvest, Gibbs Road Farm, and Gieringer’s Orchard for Rhizobiome work, which is currently ongoing.
  • Presented at National Grafting Symposium in Savannah, GA
  • Presented at MOSES conference in La Crosse, WI
• Conducted greenhouse study to determine optimum management strategies to reduce adventitious rooting for grafted tomatoes.
  • Presented at National Grafting Symposium in Savannah, GA
  • Will be presented at 2015 ASHS conference in New Orleans, LA
  • Data is currently being integrated into an extension publication.
• On-farm Collaborator, Frank Gieringer, presented his experiences with grafted plants and data collected at his farm at the National Grafting Symposium in Savannah, GA.

Impacts and Contributions/Outcomes

• We are continuing to build a strong data set with this project that will be very valuable for growers in relation to rootstock selection. Two rootstocks that we evaluated were not suitable for this area while an additional 3-4 show significant promise. This is extremely important information for growers and has been delivered effectively in order to institute change in knowledge and behavior.
• During January 2015, we coordinated a “Tomato Grafting Clinic” at the Great Plains Growers Conference in St. Joseph, MO. Within the clinic was a self-guided tour related to grafted propagation, rootstock selection, and economic data. This included printed slides, poster presentations, all tools and supplies needed for grafting, several examples of healing chambers, and numerous videos, which looped on-screen for participants to watch. We also included plants and training where participants could graft their own plants. This was a new approach, which relied on active learning by participants. We are currently surveying conference participants to determine its effectiveness.
• One of the Grower-collaborators on this project was invited to speak at the National Grafting Symposium in Savannah, GA, and his interaction with the project has established him as a leader in this area. After his experiences at the symposium, he has established better contacts for information about grafting nationally and has already networked with vendors to identify a source of grafted plants.
• One grower in Kansas that has recently seen the results of our work (Dan Kuhn, Courtland, KS) planted ~2000 grafted plants in his high tunnels. Numerous other growers are experimenting with smaller plantings.
• Our research with the propagation of grafted plants over the past three years has made a strong impact on how we grow grafted plants at the research station. In the spring of 2015, we changed our “typical” grafting procedures to match what our research results were showing us. In particular, the experiments that were conducted in spring 2014 and as part of this project gave us useful insight into the effect of leaf removal and healing chamber management. The project director has been growing grafted plants for 10 years, and this has by far been our most successful year of grafting. This trend has been communicated to growers and propagators and we expect that it will make significant impact for growers to see that we our changing our own propagation methods.

Collaborators: