Planning for Planting: What about Ear Molds in 2010?

2009 might be history, but the moldy and mycotoxin-infested corn saga will continue for months. Many growers are struggling to get rid of 2009 corn, or are taking significant dollar loss due to vomitoxin levels and associated price dock at the point of sale.

As you plan for 2010 planting, should you consider the ear mold issue?
In general, I think the answer to that question is “no”, or at least “very little”. Let me explain.

For any crop disease to develop, it is necessary to have three conditions in place:

1) Susceptible host crop

2) Disease inoculum, or source

3) Weather favorable to the development of disease

1) Susceptible host: We always have that – we grow a lot of corn. Even if you grew no corn on your farm one year, that does not mean you will not have mold issues – spores travel from your neighbor’s corn fields.

2) Disease inoculum: We always have that (for the main diseases in our region, in this case, gibberella, diplodia, and fusarium – the primary ear molds). The disease inoculum was here in 2009 – where did it come from? – and it was here in abundant quantities (of spores) to cause a huge disease outbreak.

3) Weather – Favorable weather in 2009 included, in general: Cool July, August with many hours of extended morning wetness (dews and/or fogs), cool and wet October, and unseasonably warm November. That is a very unusual weather pattern. Molds like, in general, lots of moisture, and average temperatures.

So, what is the likelihood of disease in 2010?

• We will plant a lot of corn
• Disease inoculum load is high (but remember it is always high enough to cause disease)
• If we have favorable weather for disease development, we can expect similar disease outbreak.

I’m not a meteorologist, but I think it is highly unlikely that we will see a repeat of last year’s abnormal weather. Thus, my guess that we will see little to no ear mold, as I can only assume we will have “normal” weather as opposed to a repeat of 2009 weather.

What about the higher disease inoculum load – all those spores carrying over on last year’s corn residue? Again, the key factor is whether or not we get weather favorable to disease development. If we do not have that type of weather, the increased inoculum load in corn fields would not by itself lead to high disease incidence.

As a practical planning for planting matter, I do suggest one slight defensive strategy: If you are planting corn on corn acres, make sure to choose a hybrid which has better than average disease resistance for that field. That strategy is based on the slightly increased chance of disease due to high inoculum levels in last year’s corn residue.

Overall, most Brodbeck hybrids do have good to very good ear mold disease resistance. We saw that in 2009, and our lineup has only strengthened for this coming year.

Don’t hesistate to call on Terry Jones or me, or your Brodbeack DSM, for further discussion and hybrid placement concerns as we plan to go to the field in just a couple of months.

If you have any questions or concerns please contact:

Terry Jones CPAg, Regional Agronomist @ 419.346.7786 or tmj@brodbeckseed.com or

Rod King CCA, Regional Agronomist @ 574.596.6721 or rking@brodbeckseed.com