Build Your Plan for White Mold

This summer, don’t get caught with your plants down. When fighting white mold, it pays to be proactive rather than reactive. Each year, the occurrence of white mold is heavily dependent on what we can’t control: the weather However, we can use crop management decisions and soybean varieties to reduce the risk of production losses caused by white mold. Understanding the biology of the pathogen and all the interactions with the environment and host will help build a plan for success.

Seasonal risk factors:

Weather: Cool temperatures (below < 85° F), normal or above normal rainfall, soil moisture at field capacity or above, prolonged morning fog and leaf wetness (high canopy humidity) at and following flowering into early pod development.

Field/cropping history: the amount of the pathogen will gradually increase if other host crops are grown in rotation with soybean, if there are only short intervals between soybean crops and if soybean varieties susceptible to white mold are grown.

Early canopy closure due to early planting, high plant population, narrow rows, excessive plant nutrition, and optimal climatic conditions. A dense canopy increases the numbers of apothecia on the soil surface.

Weed management: Poor broadleaf weed control favors white mold. Some herbicides used in rotation systems may be suppressive to white mold.

Management Factors:

Variety Selection: Its true there is no true variety resistance to white mold, but there is a lot that variety selection can do to set up the season right. Varieties have different plant types that can reduce disease pressure. BASF extensively tests our products for tolerance to white mold, so you don’t have to be the guinea pig. The table below has some results from a white mold trial in Hancock, WI. Ask your local BASF Agronomic Solutions Advisor for more information on placing Xitavo soybeans in white mold prone fields.  

Canopy management: In addition to the variety plant type, lowering your population to 100K can help thin the canopy without significantly sacrificing yield potential.

Weed Control: We all know killing weeds is important for maximizing yield potential, but when weeds can also help spread white mold, lets not be cute about our herbicide program. 

Fungicide: This is the heavy hitter. Every good plan has a good fungicide. The product is easy, Endura is the most effective on white mold. Timing is the hard part. To protect the flowers, we typically target a R2 to even R3 application. Scout from June 20^th to July 20^th, looking for a moderate level of canopy closure with flowers present and a forecast of rain with cloudy sub 85° days.