Pulse Growers Reminded to Test Seed

FARGO - Mar 16/06 - SNS -- Pulse producers in North Dakota and elsewhere are reminded to test prospective planting seed for the presence of Ascochyta diseases before planting.

Although all three crops are affected by Ascochyta diseases, different fungal pathogens cause the disease on each crop, according to Carl Bradley, NDSU Extension Service plant pathologist.

On lentils, Ascochyta blight is caused by a fungal pathogen specific to lentils. Ascochyta blight can be transmitted readily from the seed to the seedling at a fairly high rate.

"For this reason, growers should have their lentil seed treated with either LSP or Mertect if Ascochyta is found in the seed," Bradley says.

A recently obtained section 18 emergency exemption allows for the treatment of lentils with LSP or Mertect. Seed lots that have Ascochyta infections of more than 2% to 3% probably should not be used for seed.

On chickpeas, Ascochyta blight is caused by a fungal pathogen specific to chickpeas. Similar to Ascochyta on lentils, chickpea Ascochyta blight can be transmitted readily from the seed to the seedling at a fairly high rate.

"Because Ascochyta blight can be extremely damaging to chickpea, it is encouraged that seed lots with 0% infection be used," Bradley says. "However, if disease-free lots are not available, then lots with less than 0.3% infection could be used if they are treated with LSP or Mertect. LSP and Mertect are available for use on chickpea seed through a special local needs section 24(c) label for North Dakota."

On dry peas, Ascochyta diseases can be caused by a complex of three different fungal pathogens that are specific to dry peas.

"Because the rate of disease transmission from dry pea seed to the seedling is so low, seed lots with up to 4% to 5% infection should be OK to plant," Bradley says. "No fungicide seed treatments are available for dry peas that protect against seed-borne Ascochyta diseases in North Dakota."