Originally Published June 23, 2014
Over the last few days, hail has been reported in several areas of Manitoba. Generally, young corn has the ability to recover from early season hail damage. In corn, the growing point remains below the soil surface until the V5 to V6 stage. Therefore, the growing point should be protected and the young corn plants can recover even with significant damage to leaves. However, it is still important to examine the growing point to see if hail has by chance damage the growing point or the stalk below the soil surface. To examine the growing point, cut the stalk vertically. A healthy growing point is creamy white in color. If the growing point is watery with a brownish color, the plant is likely dying. Remember that producers and agronomists are encouraged to wait a few days to allow the crop to improve before doing any decision-making assessments.
Another consideration in corn is plants that are damaged by hail are susceptible to Goss’s Wilt infection as the bacteria can enter through the wounds caused by hail. As you are scouting for Goss’s Wilt throughout the season, focus your attention on fields that are:
- planted to a Goss’s susceptible hybrid,
- have a history of Goss’s Wilt,
- have surface corn residue, and
- may have been injured by severe weather.
Initial symptoms of Goss’s Wilt include water-soaked lesions on the leaves later accompanied by “freckling”. Bacterial ooze may also occur on the lesion, giving it a wet or greasy appearance. When the ooze dries, it leaves a shiny residue on the surface of the lesion. More information and photos can be found at: http://www.gov.mb.ca/agriculture/crops/miu/2012/2012-08-24/report.pdf.
Submitted by: Pam de Rocquigny, Provincial Cereal Crops Specialist, MAFRD