Take-all warning after record early season levels

Original article published by Farmers Guardian, Arable news 22 May, 2009

EARLY season take-all infections are at their highest level recorded in the five years of NIAB root assessments at HGCA Recommended List second cereal trial sites across the country.

The take-all index for the five sites reporting disease levels at GS31-32 this season averaged 13 on the one to 100 scale, with 80 per cent of the sites recording indexes of more than 10, and one seeing the index already verging on moderate status at 20. 

This compares with comparable take-all indexes averaging 10 or under in each of the four previous years of annual tracking from 2005, with less than half the sites recording early season indexes of over 10 on each occasion.

“This time last year infections were barely half the current level, yet we saw them build to their highest recorded average of 61 by GS65-75,” says Monsanto agronomic adviser, Rob Plaice, who co-ordinates the annual study.

“If conditions remain favourable for disease development, we could well be in for an even higher take-all season this time around.

“A dry summer like we had in 2006 should limit further take-all development. However, if the conditions remain dry, the impact of the disease on yield will be particularly severe, given the extent to which it is already compromising many root systems.

“Another wet summer may limit the yield damage, but it will lead to an even greater build-up of inoculum in the soil to threaten next year’s crops.”

 

Take-all levels at HGCA second wheat variety trial sites 2005-2009