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Beginning in 2000 and continuing into 2004, a previously undescribed disease caused significant damage to romaine lettuce (Lactuca sativa) in the coastal Salinas Valley of California. Symptoms were brownish black, sunken cavities on the crown and upper taproot. Cavities were firm, lacked signs of fungal growth, and resulted in cracking and weakening of the crown. Affected plants were stunted, uneven in growth, and unmarketable. Crisphead lettuce also developed these symptoms, although disease incidence was always lower than that for romaine. A fungus was consistently isolated from cavities. Using morphological features and molecular methods, the fungus was identified as Phoma exigua. Pathogenicity of isolates from romaine and crisphead lettuce was demonstrated on both of these lettuce types. Replicated field studies showed that azoxystrobin, boscalid, and cyprodinil + fludioxonil fungicides effectively controlled the disease. This is the first report of a crown disease caused by P. exigua in the United States. A similar disease, Phoma basal rot on greenhouse grown lettuce in the United Kingdom, had been previously observed, but no report has been published.

In 1989 penicillium stem rot affected 12 crops of protected cucumbers in the Lea Valley, Essex and one on the Isle of Wight; all of the affected crops were growing on rockwool slabs. Generally the disease incidence was low, but in one crop the majority of plants were affected and over 50% died. The causal fungus, identified as Penicillium oxalicum, occurred on stubs left after fruit picking and leaf and side-shoot trimming, and developed to cause stem softening and withering. Blue-green sporulation of penicillium on the main stem was usually surrounded by a ring of brown tissue. P. oxalicum failed to infect undamaged fruit, but was an aggressive pathogen of damaged fruit, with rot progressing more rapidly at 20°C and above than at 15°C. Inoculation of damaged cotyledon leaves induced lesions on a range of cultivars, with Cilia and Elka more resistant than others. Young plants of cv. Corona grown at 22–25°C and 90% r.h. and inoculated with mycelial plugs on the stems at fresh leaf scars developed stem lesions with Canadian isolates but not with UK isolates; in the former case wilting and collapse of the plant sometimes followed. No lesions developed following inoculation on plants grown at 70–80% r.h. P. oxalicum was consistently recovered from within the stem of most plants at the leaf axils two leaves above and two leaves below the inoculation site. Growth on potato dextrose agar of isolates of P. oxalicum from cucumber occurred more rapidly at 20°C than al 15°C. Spore germination of most isolates on agar occurred more rapidly at 20 or 25°C than at either 15 or 30°C. Isolates of P. oxalicum grew on agar amended with benomyl at 2 and 20 μg/ml but showed no growth on agar amended with iprodione at the same rates. In a crop with a high incidence of the disease, sprays of iprodione and imazalil appeared to reduce the rate of disease spread; sprays of benomyl and vinclozolin were less effective. Iprodione and vinclozolin were the most effective of five fungicides applied as paints to stem lesions to limit their development. [ABSTRACT FROM AUTHOR]

Fosetyl-Al applied once, as a spray in the autumn after fruit picking, gave very good disease control and significantly increased the number of healthy roots and marketable fruit yield in 2-year-old strawberry plants, cv. Redgauntlet. Fosetyl-Al applied twice, after fruit picking and in spring, further increased the number of healthy roots, but yields were not significantly better than the single treatment. A half-rate spray of fosetyl-Al plus a half-rate drench of captafol applied after picking and in spring gave good disease control and a yield significantly better than all other treatments. In the same crop the following year, both of the twice-yearly treatments gave a significant reduction in red core recorded in September and the two-fungicides treatment gave a significant increase in fruit yield. In a second trial, a half-rate spray of fosetyl-Al plus a half-rate drench of captafol applied after picking and in spring again gave good disease control and significantly increased fruit yield. Timing fungicide application, both after fruit picking and in spring according to root development (5 mm or 15-20 mm), had no effect on the level of red core control and little effect on fruit yield. The half-rate fosetyl-Al plus half-rate captafol treatment was significantly less effective when captafol was applied as a spray rather than as a drench. [ABSTRACT FROM AUTHOR]

The range of symptoms caused by the narcissus smoulder pathogen Botrytis narcissicola is described. Healthy bulbs inoculated with B. narcissicola, or grown in soil containing sclerotia, showed lesions in the shoot on emergence (primary symptoms). In commercial fields, B. narcissicola was commonly isolated from the bulb neck and leaf sheath of plants with primary symptoms. Plants infected by B. narcissicola one season, either with natural primary symptoms or following artificial inoculation, frequently emerged with smoulder symptoms the following season. About 40% of B. narcissicola sclerotia were viable after burial in soil for 9 months. It is suggested that infected bulbs and sclerotia present in soil are the major sources of smoulder outbreaks. Secondary infection by conidia was enhanced by damaging leaves, and open stalk ends left after flower picking were found to provide an important site for infection development. B. narcissicola was isolated from bulb necks when plants with symptoms of secondary infection had died down. A disease cycle is postulated and suggestions for controlling smoulder are discussed with reference to the cycle. [ABSTRACT FROM AUTHOR]

Cultures of Botrytis isolated from narcissus were readily identified from their sclerotial characteristics on potato dextrose agar. B. narcissicola was isolated most frequently from typical smoulder symptoms. Infection of narcissus by isolates of B. narcissicola and B. cinerea was investigated using conidial and mycelial inocula on detached leaves and bulb scales. Only mycelial inocula of B. narcissicola isolates consistently caused spreading lesions. Conidial inocula of both species typically failed to colonise healthy narcissus tissue when inoculated in sterile distilled water but B. narcissicola caused some spreading lesions after tissue damage, in senescent tissue, or following the addition of certain nutrients (including pollen) to inoculum droplets. Cultivars differed in the resistance of their bulb scales. The specificity of Botrytis-narcissus interactions is discussed. [ABSTRACT FROM AUTHOR]

The powdery mildews Erysiphe cynoglossi and E. howeana, causing disease on borage (Borago officinalis and evening primrose (Oenothera biennis), respectively, are reported for the first time in Britain. [ABSTRACT FROM AUTHOR]

The article reports of impatiens downy mildew in Great Britain. Infected leaves appeared paler green than normal, with a white, downy growth developing on lower surfaces. Symptoms were initially inconspicuous but lower leaf surfaces quickly became covered with fungus-like growth and premature leaf fall was common. Detailed examination of a representative sample revealed the sporangiophores were monopodially branched at the base, individual branches did not arise in a distinct pattern, apical branchlets were at right angles to the main axis and there was no apical thickening.

Examines the occurrence of wilt disease in a glasshouse crop of column stocks or Matthiola incana in England. Development white fungal growth; Detection of Fusarium oxysporum; Symptoms of the wilt disease.

Liposuction is a minimally invasive surgical technique, occasionally used to minimize the risk of devastating soft tissue necrosis following extravasation of noxious substances. Anaesthetists and intensive care physicians frequently use agents that may cause serious tissue injury if extravasated. Therefore, knowledge on how to manage this complication is important. We present two cases of percutaneous extravasation of noxious agents in intensive care patients and discuss their subsequent management.

Severe vascular complications of diabetes mellitus include myocardial infarction and when this occurs during pregnancy it is associated with a high risk of maternal mortality. In the absence of myocardial infarction, information is unavailable on pregnancy outcome in diabetic patients with severe coronary artery disease or with prior coronary artery bypass graft. Such a case is presented together with a review of the literature.