GUIDELINES FOR SWEET CORN SEED TREATMENT WITH FUNGICIDES

Story Type:

News Story

Author/Source:

Dr. S. Krishna Mohan, Plant Pathologist, University of Idaho

Date:

May 14 2003

Fungicide seed treatments provide insurance for good stand establishment at a relatively low cost. Unpredictable weather conditions at planting time make these treatments generally a good investment. Some of the proven products are:

Captan
A non-systemic, protectant broad spectrum fungicide, improves performance of all varieties.

Thiram
A non-systemic, protectant broad spectrum, seed treatment fungicide, improves performance of all varieties.

Maxim
A protectant fungicide against some seed-borne and soil-borne fungal pathogens.

Dividend
A systemic fungicide used to control principally Penicillium and Fusarium

Apron/Allegiance
Systemic fungicides to control Pythium species (water molds) that cause seed rot/damping-off.

Although both Captan and Thiram are broad spectrum fungicides, their efficacy against the range of fungal problems does not entirely overlap. Therefore Captan and Thiram are commonly used in combination on all seed varieties and genotypes of sweet corn seed.

Data gathered by the International Sweet Corn Development Association (ISCDA, previously known as NSCBA), indicates that for shrunken 2 (Supersweets), Captan, Thiram, Dividend and Apron/Allegiance give maximum stand establishment. For the sugar enhanced (SE) genotype, results have been more variable. However, the treatment should include Apron/Allegiance with Captan and Thiram, and in the case of some genetics and seedlots, including Dividend, should help maximize stand establishment. Below are some suggested seed treatment combinations:

SH2/Shrunken 2 (Supersweet): Captan, Thiram, Apron/Allegiance, Dividend.
SE (Sugary Enhanced): Captan, Thiram, Apron/Allegiance and, for specific varieties, Dividend.
SU1 (Normals): Captan, Thiram, Apron/Allegiance.