Barclay Crop Protection

OSR ‘Boron Watch’ returns for 2009

A free boron analysis service for growers of oilseed rape is set to continue this year, following success for the 2008 scheme launched by Barclay Crop Protection.

Boron can often be the limiting factor in an oilseed rape crop, preventing it from making full use of other inputs such as fertiliser and other crop protection products.  In fact, it's one of the most boron-dependent crops in the arable rotation, needing at least 320g/ha as Bryan Pickles, Barclay's technical sales executive explains.

"At least 80 grams of boron is removed with the seed at harvest," he says, "so deficiencies can quickly build up over just a few rotations.

"Boron-deficient crops have problems with flowering, pollination and seed set.  Boron also promotes strong root growth, which could help this season's many backward oilseed rape crops."

Symptoms are difficult to spot, he adds, and even where noticed are often attributed to other causes.  "Root growth is usually first to suffer, which is unlikely to be noticed.  Next, vascular tissue is affected, and the resulting reduction in movement through the xylem and phloem can seriously restrict nutrient supply throughout the plant.

"The severest cases of deficiency usually show signs of stem cracking, shortened stems and stunting - much of which is often wrongly attributed to a hard frost.  Likewise, reddening of the leaves is often confused with manganese or nitrogen shortages."

Mr Pickles says it's the effects on flowering that are much more common, with boron-deficient crops having 'less than optimal' flowering.  "Asynchronous flowering, where the crop simply goes on and on, is very detrimental to the crop.  It encourages pollen beetle - and all the problems associated with that pest - and because the flower petals act as a sunlight reflector, prolonged flowering reduces the crop's ability to photosynthesise, with knock-on effects on yield - pods are often not properly filled."

Growers taking part in the free analysis - which relies on plant tissue analysis - will receive a full breakdown of their results, with the top level findings being used to build an accurate map of the national crop's deficiency.

To take part, simply e-mail boron@barclay.ie with your name and address to receive a leaf sampling pack and full instructions.  Early sampling is crucial, if deficiencies are to be addressed, so Barclay is urging participating growers to return their samples as soon as possible.