2016 may have been the international year of pulse crops but around here it seems that 2017 is the big year for pulses. There have been several workshops around the area over the past several months, both Extension related and private industry. I wanted to share with everyone an e-mail I sent out to producers last week that covers some questions I have been receiving.
First, is there a need for a seed treatment? The answer would be a resounding YES. Please do this to help prevent diseases now and in the future, if nothing else for our market in the Golden Triangle. Seed treatments are recommended on all pulse crops to protect against both seed borne and soil borne fungi. Pulse crops are susceptible to many soil-borne fungi including Pythium, Fusarium, Rhizoctonia, and Aphanomyces. Seed borne fungi, such as Ascochyta, Botrytis, Sclerotinia are also a risk. Producers should always use a seed treatment as a best management practice to avoid pathogen buildup in the soil. Use products with mixed modes of action to target the different types of fungi that are present in seed and soil. It is important to rotate fungicide classes, or modes of action to avoid the development of fungicide resistance. This includes seed treatment applications as well as foliar applications.Regarding ascochyta blight, how is it spread? Ascochyta blight is the most problematic foliar disease of pulse crops. The causal agent is host specific, Ascochyta pisi causes blight on peas; Ascochyta rabiei affects Chickpea and Ascochyta lentis attacks lentil. The pathogen can overwinter in fields on crop residue for several years and in the spring the sexual spores produced from the stubble can be dispersed by the wind for up to 5 miles.
When talking about fungicides, what is the difference between those fungicides ending with -strobins and -zoles? Strobins tend to be used for more preventative measures while -zoles are more curative, or after a problem occurs, although there is a small window of preventative as well.Can a producer get away with applying at less than the recommended rates of any pesticide? Yes, you could, but are you really willing to wager that? Please apply at the recommended rates.
Do seed cleaners clean the diseases off? No, that’s another important reason to use seed treatments.
Lastly, are there recommendations for soil temperatures at which to plant pulses? Yes, 40°F is the recommendation for peas and lentils while it is 45° for Desi chickpeas and 50° for Kabuli chickpeas.