Oilseed Rape

Maxicrop enhances the development of oilseed rape tap roots, including boosting the number of fine root hairs, that are essential for strong nutrient and soil water uptake.

Applications early in the plant’s life can help improve crop establishment and, in the case of winter rape, help minimise frost damage.

Used in the spring, at the onset of stem extension, Maxicrop can help the plant access nutrients and moisture more effectively and at the same time, minimises environmental stress factors such as drought or cold.


New trials have confirmed the benefits of using seaweed extract based bio-stimulants to improve rooting and reduce stress in oilseed rape.

The most effective programme produced a 0.8t/ha (27%) yield response and a 0.2t/ha (16%) increase in total oil yield from autumn and spring use of Maxicrop Triple.

Based on oilseed rape at current farm values (£390/t) this yield improvement alone would be worth an extra £285/ha after the cost of treatment.

According to Maxicrop UK’s Mike Garner, while a range of factors are probably at play, the response is probably due to better rooting in difficult conditions and then the resultant improvement in spring and summer growth.

“Oilseed rape typically sets a very strong tap root, but is often slow to produce fine, secondary roots after emergence,” he says.

“This effect is often exacerbated in difficult autumns like 2011 and without these fibrous roots the plant’s ability to take up nutrients and moisture later on in the season is restricted.”

Mr Garner also points out that poor rooting often leads to poor establishment with poor ground cover, leaving the crop open to greater attack by pigeons and more susceptible to winter kill.

The independent trials – conducted by NDSM Ltd in 2011-12 – for the first time bolted on an autumn application at the 3-5 leaf stage of the crop to a tried and tested spring application commonly timed at stem extension.

This two pronged spray approach increased yield in the trial variety, Compass, grown on stress prone light land from 2.7 to 3.5t/ha.

While analyses of root or shoot biomass were not taken, measurements of boron in plant tissues confirmed better nutrient uptake potential of the Maxicrop Triple treated plants.

Levels in plant tissue in the spring ranged from 8-20% higher. “Treated crops were better able to scavenge more boron from the soil and effectively use it to fuel growth,” says Mr Garner.

“We have seen the benefits of a spring application of Maxicrop Triple in the past but this trial shows that the product can help improve early emergence and then maintain growth over a contrasting season.

“Fundamental research has shown that specific carbohydrates in our seaweed extracts serve as a source of food for beneficial and benign soil bacteria, resulting in a large increase in microbe numbers,” he points out.

“These microbes help improve nutrient turn-over leading to a significantly larger root mass and the increased bacterial population can also both physically exclude and compete with potential plant pathogenic soil fungi.

“In addition, soil and foliar application of Maxicrop Triple has been shown in University Research to result in greater maintenance of chlorophyll, leading to greener plants.

“This is, in part, due to a complex family of different betaines in the seaweed extract, which help reduce natural damage to the photosynthetic process.

“The practical benefits of these principle effects within the plant are to minimise some of the stresses imposed on the crop during key periods of growth and hence to keep the crop on course for high yields.

“Our advice to growers this year is to utilise Maxicrop Triple at 2-3l/ha both in the autumn and then in the spring, tank mixed with standard fungicides to counteract the varied stresses that curtail crop potential at these stages.

“While crops now have sufficient moisture to encourage early growth, many, particularly in the north, are drilled late and these will need all the help they can get to make up for the delay.”

For further information email technical.uk@valagro.com

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