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CropMonitor > Winter Barley > National Surveys > 2003 Late Assessment  



Highlights from the 2002/2003 Winter Barley survey
 
  • Total foliar disease levels were lower than in 2002. Over the last ten years only those recorded in 2001 were lower.
  • For the sixth successive year, rhynchosporium leaf blotch was the most severe foliar disease.
  • Eyespot was recorded at the second lowest severity for 10 years.
  • After the high year 2002, BYDV severity levels were low.
  • Pearl was the most common cultivar encountered with 49% of the sample.
  • For the fifteenth successive year, eyespot severity was lower in crops following grass.
  • Over half of the crops surveyed were sown in September, with 30% sown before 24 September.
  • Ninety-six per cent of crops were treated with a fungicide, a similar figure to the previous two years.
  • Each crop received on average 1.64 sprays, slightly less than recorded in 2002.
  • The most popular fungicides used were the strobilurins, 84% of all treated crops received at least one application from this group.
 
National foliar disease levels (mean % area leaf 2 affected)
Fig. 1   National foliar disease levels (mean % area leaf 2 affected)
 
 
The highest levels of Rhynchosporium were recorded in the south west region. However, the disease was recorded more often in samples from the west midlands region. Only the four major diseases were recorded in every region. Net blotch, brown rust and mildew were most severe in the north west, although only the incidence of brown rust was highest. Of the minor diseases, national levels at trace amounts, the incidence and severity of Septoria nodorum was greatest in the south west region. Yellow rust was only recorded in samples from the northern regions and Selenophoma leaf spot in samples from the south west.
Regional incidence and severity of Rhynchosporium
Fig. 2   Regional incidence and severity of Rhynchosporium
 
 
Eyespot was less severe than in 2002. Since 1990, incidence and severity have only been less in 2001.
National incidence and levels of eyespot (mean % stems affected)
Fig. 3   National incidence and levels of eyespot (mean % stems affected)
 
 
The lowest levels of damaging eyespot (moderate + severe symptoms) were recorded in the south east and the highest levels in samples from the north west and east midlands regions. Severe eyespot was only recorded in samples from the north east, north west and yorkshire and humber regions.
Regional eyespot levels (mean % stems affected)
Fig. 4   Regional eyespot levels (mean % stems affected)
 
 
Pearl dominated the sample with 49%, followed by Siberia with 9%. Of the seven most popular cultivars, the highest average level of Rhynchosporium was recorded on Regina with 11% of leaf 2 affected and the lowest on Pict with 1.0%. Levels of net blotch were also highest on Regina and yellow rust was only recorded on this known variety.
Foliar diseases on main cultivars (mean % area leaf 2)
Fig. 5   Foliar diseases on main cultivars (mean % area leaf 2)
 
 
 
Fungicide Use
Strobilurin and DMI fungicides continue to be the most popular. The proportion of crops which received a morpholine fungicide treatment fell slighly since 2002, while the proportion receiving a pyrimidine rose slightly.
Per cent of treated crops receiving foliar applications from the major fungicide groups post emergence
Fig. 6   Per cent of treated crops receiving foliar applications from the major fungicide groups post emergence.
 
 
For the second successive survey the Strobilurin group of fungicides have been the most popular group with 7% more applications than the DMI group. Only one crop was reported to have been sprayed more than twice with a Strobilurin. The majority (55%) of Strobilurin treated crops received two applications. Compared with 2002 the percentage of crops receiving a single fungicide application increased from 29% in 2002 to 35% this year. Eighty two per cent of crops received a spray aimed at GS 31 with 66% of these crops receiving a subsequent application at GS 37 onwards.
Fungicide applications during the growing season
Fig. 7    Fungicide applications during the growing season.
 
 
Sowing dates
The majority of crops were sown before 1 October. The highest proportion of crops were sown before 24 September with the majority of these sown between 12-20 September. Once again Rhynchosporium appeared to be more severe in the crops sown before October and eyespot less damaging in the later sown crops.
Sowing dates of survey crops (%)
Fig. 8   Sowing dates of survey crops (%)
 
 

 
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This website was last updated on: 07/08/2008     © Crown Copyright Central Science Laboratory 2007
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