Disease and related disorder management

Evaluation of combined fungicide and genetic resistance to control white mold in green beans (2015)

The resistance to white mold obtained so far in snap beans has been derived from NY 6020, which provides partial physiological resistance. Under light disease pressure, plants will show few if any symptoms, while under heavy pressure, the plants may show a moderate level of infection (whereas susceptible BBL types will be 100% molded). Cultivars with this form of resistance would not need any supplemental control with fungicides, whereas under heavy pressure, fungicides might be required, but at a reduced frequency or quantity. The objective of this study was to determine whether OR6771 would benefit from an integrated mold control approach that included fungicides typically used in snap production, Topsin M and Rovral tankmixed.

Winter Squash Production Resources

It is difficult to find information on winter squash production and storage. This page aggregates resources relevant to Oregon winter squash growers.

Alex Stone is fixing broken links and adding new content in January 2021 - come back soon!

Winter Squash Storage Rots and Their Management

Farmers in western Oregon can lose a significant portion of their winter squash in storage to storage rots. In winters 2012-2015 we collected samples of stored squash with rot symptoms from farmers in western Oregon and the OSU Plant Clinic identified the pathogens causing those rots. This article includes photos of the rot symptoms, descriptions of the diseases, and information on how to control storage rots.

White Mold of Snap Bean and Other Vegetable Crops

White mold is a serious foliar and pod disease of snap beans grown for processing in western Oregon as well as in all major snap bean production regions in the US. White mold has a wide host range as it is a pathogen on more than 400 plant species.

Sweet corn diseases and their management in the PNW: seed treatment evaluations and development of Fusarium-free seed (2013)

Research report to the Oregon Processed Vegetable Commission

Cindy Ocamb
OSU Dept. of Botany and Plant Pathology

Mold Management in Snap Bean (2013)

Research report to the Oregon Processed Vegetable Commission

Cindy Ocamb
OSU Dept. of Botany and Plant Pathology

Liming and clubroot control in brassicas- handout for 2013 Veg Field Day

Clubroot is becoming an increasing problem on Willamette Valley vegetable farms. Most cultivated brassica crops (broccoli, cauliflower, cabbage, etc.) are highly susceptible to the disease, which is caused by the soilborne fungus Plasmodiophora brassicae. In severe cases it can cause significant crop losses, and heavily infested fields may be taken out of production. Once a field is infected, eliminating the pathogen is difficult if not impossible because its thick walled resting spores have been shown to remain viable in soil for up to 18 years. As a result, once pathogen populations have developed to economically damaging levels, the goal of the farmer is to manage rather than eradicate the disease. One effective control strategy is to raise the soil pH to ≥7.2 through liming.

Sweet corn diseases and their management in the PNW: Seed treatments and development of Fusarium-free seed

Principal Investigator: Cynthia M. Ocamb, Ext. Specialist & Associate Professor
Botany and Plant Pathology, OSU – Corvallis
e-mail: ocambc@science.oregonstate.edu

Collaborator: James R. Myers, Horticulture, OSU – Corvallis

Objectives:

1. Conduct an evaluation of materials currently registered on sweet corn for control of seed rot and seedling blight.

Mold Management and Sclerotinia Ascospore Trapping in Snap Bean

Principal Investigator: Cynthia M. Ocamb, Ext. Specialist & Associate Professor
Botany and Plant Pathology, OSU - Corvallis
Telephone: (541) 737-4020
ocambc@science.oregonstate.edu

Cooperators: David H. Gent, USDA-ARS, Corvallis
Robert B. McReynolds, North Willamette Research & Ext. Center, OSU
Jim Myers, Dept. of Horticulture, OSU

Gray and White Mold in Snap Beans

A number of growers and agricultural professionals have asked me whether we are seeing resistance to mold in snap beans to our currently registered fungicides. The short answer is, not to my knowledge. In a normal year, the primarily threat to snap beans is white mold (Sclerotinia sclerotiorum). When we have a cool, wet spring, we see both white mold and gray mold (Botrytis cinerea). Gray mold is a game changer. Gray mold control requires a tank mix, early timing, and a two spray program.