Does planting date affect soybean rust severity?
The optimum planting date in Iowa is the last week of April and first week of May. Growers need to adhere to this schedule to achieve high yield potential. In the case of other diseases, (e.g., corn rust and wheat stem rust) early planting usually results in lower disease severity. Thus, an earlier planting, for example 1 May, will mature earlier in the fall and therefore avoid a possible late infestation of ASR, than a field planted late, for example 1 June. In reality, it is too early to be changing cultural practices since we do not know enough about the effect rust on U.S. crops, including when it will occur and how it rapidly it will spread.