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Zinc is the secret to promoting big roots

Seed treated with a zinc-ammonium acetate has been found to produce more vigorous roots than those treated with fungicidal seed treatments only.

In trials across North Yorkshire in 2017, winter wheat seed of the variety JB Diego treated with Radiate, a zinc-ammonium acetate, were found to have a greater root length than those treated with fungicidal seed treatments only.

The products considered in the trial contained either prothioconazole and tebuconazole, fludioxonil and sedaxane, or just straight fludioxonil.

The trial also sought to measure the root-promoting claims made for fludioxonil and sedaxane, but no such effects were observed. When applied on its own, treated plants produced smaller roots than the untreated.

As table 1 shows, the greatest response came when Radiate was co-applied with Redigo Pro (prothioconazole and tebuconazole), though in all treatments root length increased when Radiate was included either on its own or in combination with a fungicidal seed treatment.

Root length (cm) 25 days after emergence

Untreated 43.27
Radiate (2.0 ltr/t) 52.65
Fludioxonil + sedaxane (2.0 ltr/t) 41.77
Fludioxonil + sedaxane (2.0 ltr/t) + Radiate (2.0 ltr/t) 53.78
Fludioxonil (2.0 ltr/t) 49.10
Fludioxonil (2.0 ltr/t) + Radiate (2.0 ltr/t) 51.28
Prothioconazole + tebuconazole (0.67 ltr/t) 52.08
Prothioconazole + tebuconazole (0.67 ltr/t) + Radiate (2.0 ltr/t) 55.35

Source: NDSM, 2017. LSD (P=0.05) 7.93; %CV 21.20

How does it work?
Radiate is a unique seed treatment that promotes root vigour by stimulating auxin production (a natural plant hormone). It is pH neutral an is recommended for use on all winter and spring cereals and oilseeds with trials showing it increases winter wheat and oilseed rape yields by 0.4t/ha on average.

It can be co-applied with any seed treatment used in cereals and oilseeds, including Vibrance Duo (fludioxonil and sedaxane), Beret Gold (fludioxonil) and Redigo Pro (prothioconazole and tebuconazole.

This yield increase is attributed to bigger roots promoting improved drought tolerance and a greater ability to take up essential nutrients. As growers strive to improve yields, promoting a plant’s root activity is being recognised as an important step to better performance.

Greater root mass enables the plant to locate and absorb more water and nutrients which supports general crop health, photosynthesis and, ultimately, yield.

The benefit of greater root mass is also seen on farm with growers reporting faster establishment and yield increases even where the soil profile and pH status suggest zinc should be freely available.
Even on heavy soils which is not normally associated with a zinc deficiency, growers have reported yield gains from using Radiate.

One user reported an average yield response of 0.37t/ha across more than 1000 hectares.

The pictures compare fludioxonil + sedaxane (2.0 ltr/t)-treated seed with fludioxonil + sedaxane (2.0 ltr/t) + Radiate (2.0 ltr/t)-treated seed. The greater root structure of the Radiate-treated seed can be seen clearly in the second picture.