Hybrid Management in 2017
Dec 22Hybrid Management in 2017
In 2015 and 2016 Maizex conducted extensive testing to evaluate various aspects of hybrid management. The end goal of this testing is to capitalize on hybrid differences to better fine tune management options and improve hybrid positioning.
Some of the key comparisons include treating hybrids with a Standard versus an Intensive Management package. This Intensive Management includes: 1) increase plant populations by 5,000 plants per acre - this generally means moving final stands from 30-33,000 to 35-38,000 plants per acre; 2) adding an additional 50 lbs of nitrogen per acre – this represents increasing nitrogen rates from a range of 125-175 lbs per acre up to 175-225 lbs per acre, and 3) applying a foliar fungicide at VT stage (Tassel) in contrast to no foliar fungicide in the Standard Management scenario.
In 2016, across 90 hybrid/site comparisons, the average yield increase for Intensive Management was 15.5 bushels per acre. This is in fairly sharp contrast to the results from 2015 when the average increase from Standard to Intensive management was 26 bushels per acre. The lower rainfall totals, especially in the June to July window, had a significant impact in lowering the yield gains from the extra inputs. These contrasting years have helped build confidence in how to score the hybrids for management responsiveness across a wide range of environments. The tables at the end of this article provide the most recent scores for each hybrid and some additional management insights. Hybrids like MZ 3033DBR, MZ 3066DBR, MZ 3410DBR and MZ 4525SMX continued to demonstrate a more defensive nature with stable yields, but were less responsive to extra population, nitrogen or fungicide. Hybrids like MZ 2810DBR, MZ 3484SMX, MZ 3964DBR, MZ 4280DBR and MZ 4640SMX showed significant yield increases in response to the extra inputs even in a relatively dry year.
The guidelines can be used to identify hybrids that have high scores and are therefore more suited for higher yield potential fields or for adding extra inputs. Low scoring hybrids can be viewed as hybrids which often yield well across a range of environments but would not be the first choice to add extra N or a foliar fungicide unless N shortage or leaf diseases were evident.
All or Nothing or Something?
We often get asked to separate out the impacts of the intensive management components. That is, how does population, nitrogen or fungicide alone impact yields compared to when all three are applied in a package? This sort of testing was not done at all sites, but we have a few locations where we attempt to isolate the impacts of the inputs individually. In 2016, response to population alone was lower than average, similarly the response to the extra 50 lbs of N was profitable in only 7 out of 20 sites, but a profitable response to fungicide occurred about 75% of the time.
So if you had looked at the 90 day forecast in April and decided because of dry weather to not push populations in 2016 beyond 33,000 ppa, you made the correct call in many areas. If you had observed dry weather in May and June and/or monitored soil nitrate tests and decided to leave N rates at 160 lbs instead of topping them up to 200, again, you probably made the correct call in many areas. However, if you saw dry weather in July and very low leaf disease pressure and decided to not spray a fungicide at VT, our data would suggest, at least on some hybrids, you may have left some yield on the table.
In moving forward, we anticipate that Maizex growers will be able to use a range of tools (weather data, soil N testing, soil moisture monitoring, aerial imagery, etc.) in conjunction with state-of-the-art hybrid management guidelines to consistently improve their corn productivity and profitability!
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