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Vegetable Crops
Project: 31  Control of Bulb Mites in Onions                                           
Project Leader:  Thomas A. Turini                                                       
Objective:  Bulb mite damage can be eliminated or reduced by the application of materials that have shown activity against other mite pests.  Bulb mite damage can be eliminated or reduced by the application of an increased amount of pre-plant fertilizer.

Project: 34   Evaluation of Insecticides and Plant Activators as a Component of a Program to Control Tomato Spotted Wilt in Processing Tomatoes 
Project Leader: Thomas A. Turini
Objective: 

Hypotheses tested:  There are alternatives to the standard organophosphate and carbamate insecticides currently used commercially that are effective against thrips.  Plant activators can reduce damage due to TSWV and increase yield of processing tomatoes.

Specific objectives:  Compare the efficacy of insecticides with different modes of action against thrips on processing tomatoes.  Assess the effect of plant activators on TSWV incidence, severity and yield.
 

Project: 35   Melon Variety Evaluation and Cultural Practices Research 
Project Leader:  Thomas A. Turini
Objective:   Develop production and fruit quality information on cantaloupe, honey dew, and watermelon varieties adapted to the central San Joaquin Valley.

Project: 40   Cole Crops, Spinach, and Pepper Culture in the South San Joaquin Valley 
Project Leader:  Michelle Le Strange
Objective:   Conduct variety and weed control studies in selected vegetable crops; and to investigate other crop management practices, which might benefit production, e.g., fertility and insect or disease management.

Project:41  Fresh Market and Process Tomato Production in the South San Joaquin Valley 
Project Leader:  Michelle Le Strange
Objective:  To conduct several field trials in processing and fresh market tomatoes.

Variety Trials:   Most will involve varieties of tomatoes that are decided upon at industry meetings that are held annually in November and December. All fresh market tomatoes are transplanted (two annual field studies are planned: rounds and roma varieties, but tomato spotted wilt virus resistance lines are also becoming available and need to be investigated for their performance). The trend of processing tomatoes is moving towards using transplants and drip irrigation, whereas in the northern SJV most growers use furrow irrigation and are not likely to switch soon. Three to four processing variety trials are planned: an early and midseason trial that is direct seeded and one of those that will be transplanted. 

Evaluation of Soil Treatments to Control Corky Root Rot: Corky root rot is generally a problem in early tomato plantings under cool conditions, especially in fields with a long history of tomato production. The fungus, Pyrenochaeta lycopersici, survives for long periods in the soil as microsclerotia. Currently there are no treatments used to reduce disease in the subsequent tomato crop in fields with a history of corky root and high population of the fungus. Two other products are available for testing and Fresno growers have asked the CA Tomato Research Institute that they be tested and compared.
Evaluation of Extended Field Storage Varieties over Time of Harvest: It is well documented that yields of processing tomatoes decrease during periods when high-sustained air temperatures occur and disrupt fruit set. Certain varieties have been bred for Extended Field Storage and need their quality and quantity components compared when harvested over an extended period to see if they could be planted under more optimum conditions for fruit set and held for harvest. 

Project: 58    Evaluation of Materials for Lettuce Downy Mildew Control           Project Leader:   Thomas A. Turini                                                                      Objective:  The objective is to evaluate currently unregistered fungicides for use on lettuce for downy mildew control.

Project: 59  Evaluation of a Predictive Model for Control of Tomato Powdery Mildew                                                                                                                            Project Leader:   Thomas A. Turini                                                                         Objective: 

  1. Compare programs for powdery mildew control on processing tomatoes, one of which will be based on a predictive model.
  2. Evaluate registered and unregistered fungicides for efficacy under conditions present in western Fresno County.
Project:  79   Evaluating Drip Irrigated Double-Row Tomatoes on 80-Inch Beds Project Leader:   Thomas A. Turini     
Objectives: 
  • Compare yield and quality of processing tomatoes on alternative drip irrigation systems with different plant populations. 
  • Compare economics of these systems. 
  • Assess the effect on cropping flexibility of these systems.
Project: 80  Influence of Vine Trimming on Processing Tomato Yield and Quality  Project Leader:  Thomas A. Turini
Objective: 
  • Compare incidence of Tomato spotted wilt virus (TSWV), cucumber mosaic virus (CMV), Iris necrotic spot virus (INSV) and tobacco mosaic virus (TMV) in trimmed and non-trimmed tomatoes. 
  • Assess any differences in foliar diseases and identify casual agent(s) associated with fruit rot. 
  • Overall yield and quality - including percent fruit rot, and TSWV-affected fruit.

Project: 81 - Comparison of Materials and Programs for Control of Melon Powdery Mildew                                                                                                            Project Leader:  Thomas A. Turini                                                                    Objective: 

  • To document the efficacy of new chemistries against P. xanthii.
  • To provide information on the effect of the use of fungicides with different modes of action in rotation.  This is to encourage Pest Control Advisors to use fungicide rotations for resistance management.
  • To determine the status of fungicide resistance in Central California.