Our Mission:

Founded in 1968, The California Tomato Research Institute, Inc. is a non-profit organization of processing tomato growers. As the industry's research sponsor, the Institute's purpose is to identify, fund and direct research to maintain and enhance the economic viability of California's processing tomato industry with emphasis on production, product quality and the environment.


2020 Processing Tomato Research Projects

Sponsored by the California Tomato Research Institute


Agronomic Management


How do different soil types impact physiology, yield, and quality under late-season deficit irrigation?

Mallika Nocco

Building on the work of Martin Burger and others, this new Extension Specialist is developing an industry accepted understanding of what the best and most utilitarian metric is for improving timing around deficit irrigation. Recognizing the need to develop clear monitoring guidelines this researcher has already convened a “Product Advisory Group”, including CTRI members in addition to representatives from the major commercial players in irrigation management technology, to help guide the project.

Optimizing potassium fertilizer uptake efficiency while minimizing costs in processing tomato

Nicole Tautges & Brenna Aegerter

A continuing project with promising early results which further confirms the findings of others (Hartz & Miyao) that potassium (K) is an increasingly limiting factor in processing tomato production. The second year will compare variable application types and timings, in-field. The treatments proposed represent real practice in commercial fields. This study is providing tomato growers with new information on K fertilizer application tradeoffs for both productivity and economics.

Effects of soil management on processing tomato associations with mycorrhizal fungi

Rachel Vannette & Amélie Gaudin

The goal of this project is to develop management recommendations which will assist growers in enhancing the beneficial mycorrhizal populations in their fields. This will be accomplished through the sampling and testing of soils from variable management practices, through trialing mycorrhizal inoculants in-field, and through the testing and development of a novel method for grower assessment of inoculum potential. The microbiome of the soil is one of only a handful of areas in processing tomato production where more than incremental improvements are possible. Watch this space for projects which hold the promise of short term, practical application as well as projects with long term high payoff outcomes.  

Influence of compost application rates and timing on nitrogen management and processing tomato productivity and quality

Zheng Wang & Anthony Fulford

The impact of manure based composts on processing tomato production is well characterized. Less understood, but increasingly practiced, is the use of green waste composts. With mounting pressure from the Irrigated Lands Regulatory Program to accurately account for all sources of  nitrogen, the outputs of this project - which is being done in commercial fields with member growers - will allow for a better understanding of the efficacy of green waste composts and the impacts of their use on nutrient management plans.


Germplasm & Variety Development


C.M. Rick Tomato Genetics Resource Center

Roger Chetelat

Annual support of the valuable germplasm bank.  Past exploration of the genetic materials housed here have added significant utility and $ value to the processing tomato industry in the areas of disease resistance, field manageability, marketable traits, and yield. With the reality of increased disease pressure, maintaining this collection is of paramount importance. Including our 2020 annual support, the CTRI has provided this industry resource with over $600,000 since 1990.

Completion of Insect Resistance Source Line for Transfer Resistance to Insects and Insect Transmitted Virus in Processing Tomato

Martha Mutschler-Chu

BCTV and TSWV are existential threats to the processing tomato industry - threats which we currently have no built in genetic resistance for. With promising field trials at the West Side Research and Extension Center in the past two seasons showing WFT control and the possibility of leafhopper control this researcher from Cornell, working with Cornell produced tomato lines, is two years away from releasing lines to seed companies which will be ready to be used for rapid transfer of the desired traits. This project has 1:1 matching dollar support from the seed industry.

Breeding for Water Stress Tolerance by Combining Two Wild Species in Tomato

Dina St. Clair & Amy Groh

Leaning on the genetics of wild tomato, specifically S. habrochaites and S. pennelli, this team is working to make the genetics specific to water use efficiency (WUE) and water stress tolerance more readily available to the breeding community. The end result of this work is expected to be fully characterized introgression lines that can serve as a base resource for incorporating the desired traits of WUE and water stress tolerance into current commercial material.


Insect & Invertebrate Management


Evaluation of alternative nematicides for the control of Root-Knot Nematodes of processing tomatoes

Jaspreet Sidhu

Performing field trials at the Kern County UCCE Research Station, this team has previously alerted the industry to the significance of Nimitz®, Velum ®, and Salibro ®. These are trials that the CTRI will support, in full, in years where new products are coming on the market. Products added to the trials in 2020 will be Calcium Cyanamide and a product in development from Syngenta. Significant cost sharing with industry and other commodity boards allows this work to continue.

Consperse Stink Bug IPM Update

Tom Turini

Besides basic IPM tactics (keeping borders clean, etc.) our industry has little knowledge of effective control measures for this pest of economic significance, particularly those control measures possible once a problem is discovered. This proposal is not simply a reboot of past work, using past learnings while bringing in new collaborators, the objectives include trap optimization, alternative spray technology, and chemical efficacy.


Disease Management


Vectored Viruses


The resistance breaking strain of TSWV in California processing tomatoes: monitoring, improved detection and screening for resistance

Bob Gilbertson & Neil McRoberts

Resistance breaking (RB) TSWV strains, confirmed in 2016, now pose a major threat to the utility of resistant varieties across all growing regions. The expectation of this ongoing work is to develop and extend resistance management tools (including diagnostics) AND discover new sources of genetic resistance.

Beet Leafhopper Efficacy Comparison

Tom Turini

A project in cooperation with the BCTV Control Board, the aim is to gather information on possible alternative treatment options, both conventional and organic, for this pest of annual economic significance.

Varietal response to resistance breaking TSWV

Tom Turini

Working directly in dealer trials flagged to have high TSWV pressure, this researcher ran a pilot of this study in 2017, which was scaled up in 2018 and 2019. The 2020 project (using no new funds – only carryover funds from 2018 and 2019) will add more data points, building on the significance of prior year’s trials. With no quickly transferable sources of genetic resistance believed to have been identified to date, understanding the tolerance of our current commercial varieties will be increasingly important in areas of high pressure.


Southern Blight


Evaluation of Streptomyces isolates as biocontrol agents for Southern Blight of Tomato

Isolde Francis

Southern blight is a continuing challenge in those areas and fields which have historically held high populations of the fungal pathogen, particularly those areas with limited rotational options. This proposal from CSU Bakersfield brings in preliminary data from collected Bakersfield production area soils. Southern blight in-season management has proven itself as practically impossible due to the constraints surrounding getting effective materials into the crown of the tomato plant. The proposed solution sidesteps this challenge by utilizing living populations of biocontrol agents which are understood to be maximally effective against Southern blight (and potentially other soil-borne pathogens).


Fusarium Diseases 


Developing accurate, rapid and cost effective tools for diagnosis and predictive monitoring of Fusarium pathogens of tomato

Cassandra Swett

The Swett Lab will continue its crucial work of developing rapid diagnostic tools for the detection of Fusarium pathogens, including Fol race 3, in field and for testing the level of inoculum load risk in soil. The continued partnership with the USDA Martin Lab adds significant value to the diagnostic test development. This work not only gets us closer to the first step of any disease mitigation program (accurate diagnosis) but also builds up the genetic library of fusarium which will be needed in the future for testing against F4 and for genetic resistance in varieties.

Developing effective crop rotation strategies for Fusarium wilt management

Cassandra Swett

The big picture goal (which is set for year end 2020) for this project is to develop crop rotation recommendations that reduce Fusarium wilt risk. To this end, the Swett Lab will continue several ongoing project objectives to understand risk thresholds, define the survival curve and assess risk based on rotation.

Control strategies for F. falciforme, a newly recognized and widespread cause of premature vine decline

Cassandra Swett, Brenna Aegerter & Tom Turini

We have a previously unrecognized, serious vine decline syndrome in the state, caused by the newly characterized (2018) F. falciforme. This projects aims to rapidly develop an integrated management strategy for this pest to include recommendations covering: tolerant cultivars, cultural practices (such as crop rotation), and chemical control.

Disease diagnosis, pathogen movement / emergence monitoring, new pathogen identification and Fusarium wilt race 4 monitoring in support of the processing tomato industry

Cassandra Swett

The Swett Lab, without any university level support, is THE diagnostic services lab for the entire processing tomato industry in California. Diagnostic activity is leveraged significantly for advancing research and outreach efforts which includes activities outside of simple diagnostics such as: the recognition and characterization of new pathogens, the mapping of disease spread regionally and from year to year, the ongoing training of faculty, staff and Farm Advisors, and the provision of diagnostic support tools. An industry resource which our grower members AND the industry as a whole benefits greatly from. 


Weed Control & Management


Pre-emptive development of management strategies for Branched broomrape in California processing tomato systems

Mohsen Mesgaran & Brad Hanson

A continuing project, started in 2019. This work is in direct response to a specific industry need - several recent findings of this invasive pest in processing tomato fields. There are four targeted areas of prioritization in this work: rapid detection, containment, eradication and long term management. Western Region IR4 and the CDFA are providing substantial dollar support, in addition to CTRI direct project funding. An intentional strategy of forward planning, as the industry patiently awaits this pest’s inclusion under future Federal crop insurance plans.

Weed control and cost-benefit analysis of automated cultivators to control within-row weeds in processing tomatoes

Amber Vinchesi-Vahl & Scott Stoddard

With the recognition of increasing labor costs being an ever more significant constraint this is an effort to introduce the industry to the realities of the spectrum of weed control options currently available. The second year of this work proposes to expand the range and scope of the trials to multiple fields in two regions with two Farm Advisors and multiple modes of weed control - standard, finger weeders, and automated. This is an on-farm, cost effective approach to evaluate the use of these new technologies.