Now that your corn is off to a great start, there are still a few tools in the tool bag to take your corn silage crop to the next level. As we are quickly approaching tasseling in most areas of the province silage producers should be considering the application of a VT Fungicide to their corn fields. This is not a new strategy but there is increasingly more interest in these applications. There are several different benefits to applying foliar fungicides to corn silage: increased yield, improved feed quality and reduced mycotoxin levels.
Image 1. A High Clearance sprayer applying to a VT Corn field. Source: https://talk.newagtalk.com/forums/thread-view.asp?tid=70760&DisplayType=nested&setCookie=1
Fungicides help to keep plants greener and healthier which allows them to produce more grain and plant material. Leaf diseases such as Northern Corn Leaf Blight (NCLB) and Common Rust can cause a significant loss of yield (See Image 2 and 3). Not only do leaf diseases reduce leaf biomass, they also decrease the photosynthetic area of the plant and steal energy that does not end up in your feed bunk.
Maizex and BASF have done numerous trials to evaluate the yield response of silage corn to a VT-R2 applied fungicide. Figure 3 illustrates the dramatic yield gain at the Maizex site near Woodstock in 2016; notice that yield gain in some hybrids are in the range of 3-4 tonnes of silage per acre. These yield improvements are generally more than expected, but does give an indication of what yield improvement can be attained. BASF reports that on 51 small and large scale trials across Ontario and Quebec where 4 different fungicides were applied at VT-R2 on silage corn, there was a 1.3 tonnes/ac advantage on average to applying a foliar fungicide to silage corn.
A 1.3 tonnes/ac increase in yield is significant, providing an excellent return on investment on the cost of a foliar fungicide and application. One caution would be that when you apply a foliar fungicide to silage corn, the moisture content at harvest will be 3-4% higher than if a fungicide was not applied. This can help create a wider harvest window as plant dry down is slower allowing you more time to harvest your crop at the correct moisture content. However, the slower dry down could also cause some grief if your silage varieties are already at full maturity, applying a fungicide can add up to a week of harvest delay which may be too late for the optimum harvest period in your area.
Applying fungicides to silage corn can also increase the quality of the feed. Fungicides help to keep the plant leaves healthy and free from disease. Harvesting a healthier plant results in a higher quality feed with higher productivity out of your livestock. BASF has conducted 23 trials over the past six years in Ontario and Quebec with an average increase of 65.12 kg of milk/tonne when a VT fungicide was applied to corn silage fields (see Figure 7). When calculated out to a per acre basis and assuming a yield of 25 tonnes/ac, this equates to an additional 1709L of milk per acre. If producers could achieve even a portion of that increase in feed quality in their operation, it provides a considerable return on investment.
Maizex is conducting trials in 2018 to evaluate the use of foliar fungicides and their reduction of mycotoxins in feed samples. The indication to date is positive but more testing is needed to fully understand effectiveness. A suggestion is if a producer is looking to reduce mycotoxin levels in their feed, products such as Proline®, Caramba® or Caramba® co-mixed products such as Headline® AMP should be considered given their control of diseases that can lead to mycotoxin production.
If Western Bean Cutworm is also a concern for you, Foliar Fungicides can also be tank mixed with insecticides such as Coragen, Delegate and Voliam Xpress. If Western Bean Cutworm levels in your fields are above threshold and you are going to apply an insecticide, this may be a suitable timing to do both applications at the same time. Check with label requirements for tank mixing before applying and insecticide and fungicide together. Priority should be given to proper timing on the insecticide over the fungicide.
Given how foliar fungicides are demonstrating significant improvements on corn silage production, we suggest that you consider using a foliar fungicide on your silage acres in 2018.
Written By Adam Parker, Maizex Seeds http://www.maizex.com/