Arable News

  • Written by: Farmers Guide
  • Posted:

BBRO Advisory Bulletin No 9 – W/C 25th May 2015

Crop growth

Recent rain and slightly warmer nights are helpingto promote more rapid growth across all factory areas. Most crops look well,although slightly behind the exceptional start of 2014, and plant populationsare good unless impacted by earlier capping or wind blow issues.

Weed Control

Weed control continues with excellent levels ofcontrol being reported in many crops. Thistles are now at the right stage fortreatment, a two split application of clopyralid will soon tidy these up.

Outside of fields, groundskeepers on old cleanerloader sites are easy to find and it is really important to spray these offwith glyphosate ASAP as they will harbour a range of pests and diseases.

Last week, the BBRO attended a weed controldemonstration in France where a number of different tractor hoes were beingevaluated. Guidance technology is certainly making this job much faster, withenhanced levels of accuracy. Coupled with band spraying, is it something wemight see more of in the future?  We’ll cover the demonstration in afuture issue of the British Sugar Beet Review but if anybody would likeinformation about the event, or hoeing in general, please get in touch.

Pests and Diseases

To date, few reports have been received concerningdowny mildew, although individual affected plants have been reported inNorfolk, Suffolk and Lincolnshire over the last 7 days.

Aphid numbers are starting to increase and 47 peachpotato aphids were caught at 11 out of 30 monitoring sites up until 20th May.Most were found in the Cambridgeshire area. Aphids will continue to build asweather favours their movement and in field build-up. However, there are noreports of aphids on treated crops although aphids (up to 20 per plant) couldbe found on potato volunteers in southern Lincolnshire on 26th May.

Of greatest current concern is leaf miner larvaeactivity, particularly (although not exclusively) around theWash.  In extreme situations up to 400 eggs per plant (6-8 trueleaves) were found yesterday and there was evidence to suggest that seedtreatments were running out of steam around 10-11 weeks post sowing.  Weare particularly concerned at this developing situation as there are noapproved foliar insecticides available for subsequent control post seedtreatment (please remember that dimethoate is no longer approved for use onsugar beet for mangold fly control).

The BBRO would appreciate any commentsabout this pest, either egg numbers and/or leaf mining damage to gauge theextent of the current problem. We are currently monitoring adult mangold flynumbers from traps and will be assessing a range of insecticides in trial thisyear.

  • Written by: Farmers Guide
  • Posted:
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