By John Ippolito, Regional Crop Specialist, Kindersley
Spring wheat and durum wheat grown in the 2016 crop year is likely to present some challenges when it must be used for seed in 2017. The level of fusarium infection is presenting some issues that may become evident in the form of seedling blights as the crop emerges. There may also be reduced germination as a result of less-than-ideal harvest conditions.
In terms of fusarium infection for wheat seed, we are recommending using the following flow chart as a decision making tool.
Keep in mind that this chart is related to decision-making purely based on level of fusarium infection and species of fusarium that are present. It is also important to note that the number of fusarium-damaged kernels is not a good indicator of level of infection; the reality is that some of the kernels that look good may also be infected.
Wheatland Conservation Area conducted a study in 2012 to determine the impacts of seed size, seeding rates and use of seed treatments with both durum and spring wheat. They used three seed lots with a low, medium and high seed weight, two seeding rates, and treated with either a dual purpose seed treatment or no seed treatment. The treatments were additive from a weak agronomic system of low seed rate using untreated seed with a low thousand kernel weight, to a superior agronomic system that used heavy seed that was treated and combined with a higher seeding rate. Measurements included plant populations and yield response.
There was a significant yield response from increasing seed size and using seed treatments with both spring and durum wheat. Yield responses to seed treatments were greatest in the weak agronomic system using low seed weights and seeding rates.
The results of this trial may shed some light on what producers may have to do in 2017. Seed quality is less than normal with fusarium infection and lower germination levels. As a result, we can equate this to the weak agronomic system encountered in this study. The end result is that we should probably be planning on cleaning heavy to get as large an average seed size as possible, increase seeding rates to account for reduced germination and seedling blight issues, and plan on using a seed treatment to get the highest yields possible.
For more information, please see Cropping Systems Response to Seed Treatment, Seed Size and Density.