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Functioning Tri13 and Tri7 genes are required for the production of nivalenol and 4-acetyl nivalenol, respectively, in Fusarium species producing type B trichothecenes. Mutations have been identified in isolates which are able to produce deoxynivalenol (DON) but unable to convert this to nivalenol (NIV). In such isolates of Fusarium culmorum, the Tri7 gene is deleted entirely. PCR assays specific for functional and nonfunctional/deleted versions of Tri7 and Tri13 were used to determine the ability of 153 single spore isolates of F. culmorum to produce the 8-ketotrichothecenes deoxynivalenol and nivalenol. The isolates were collected from 76 different locations across England and Wales between 1994 and 2002. Four isolates were also obtained from one field in Scotland. Both DON and NIV chemotypes of F. culmorum were identified, with DON chemotypes predominating overall. In addition, all DON chemotypes were shown to produce 3-acetyl DON using primer sets developed to Tri3. From fields where more than one E culmorum isolate was obtained, isolates were not exclusively of a single chemotype. Differences in the distribution of DON and NIV chemotypes were identified, with a greater proportion of NIV chemotypes present in the south and west of England and Wales, whereas a greater proportion of DON chemotypes were found in the north and east of England. Seasonal differences in the ratio of DON:NIV chemotypes were indicated. However, these were related to seasonal variation in the distribution of F. culmorum. [ABSTRACT FROM AUTHOR]

Cytoplasmic male-sterile winter wheat, grown in the field in England with a limited supply of pollen, set over 80% less seed than fertile wheat. Wheat ears precociously inoculated with ergot (Claviceps purpurea) initiated local natural epidemics of disease at flowering and, within 1.5m of primary foci, scierotial abundance at harvest was correlated inversely with seed set. Scierotial mass in poorly pollinated male-sterile wheat comprised more than 20% of the threshed grain yield, in contrast to only 07% in fertile wheat. [ABSTRACT FROM AUTHOR]

Apotheeia of Tapesia yallundae were collected from a set-aside straw stubble site in Lincolnshire in March 1993. Single ascospore isolates were obtained which produced colonies with morphologies and growth rates characteristic of the R-pathotype of Pseudocercospotella herpotrichoides. Isolates were confirmed to be R-type by the use of randomly amplified polymorphic DNA (RAPD) markers. These observations confirm that T. yalhundae is the teleomorph of the R-type of P. herpotrichoides and represent the first detection of the sexual stage of the R-type in the UK. [ABSTRACT FROM AUTHOR]

In 1976 one breeding colony of the Colorado beetle, Leptinotarsa decemlineata (Say), was found in England. This was the first colony to be found since 1952. In addition 241 single beetles were found in England and Wales, of which 23 were alive. This is the largest annual total for 27 years. Seventy-six single beetles were found in Scotland, of which two were alive. Details of these finds are presented. The outstanding features were the large numbers associated with wheat (240) from Holland and France and with rye seed (49) from Holland. [ABSTRACT FROM AUTHOR]

In 1973, 103-108 adults of the Colorado beetle, Leptinotarsa decemlineata (Say), were found, of which 51 were alive. This is the largest annual total for 20 years. Details of these finds are presented. The outstanding feature is the large number (74-79) associated with French wheat. [ABSTRACT FROM AUTHOR]

Drechslera tritici-repentis anamorph of Pyrenophora tritici-repentis was found in diamond-shaped. dark-brown lesions on leaves of several winter wheat crops in England and Wales. Lesions were darker than the otherwise similar lesions caused by Septoria nodorum. [ABSTRACT FROM AUTHOR]