Hemocyte diversity of the American bollwormHelicoverpa armigera

The hemocytes of the American bollwormHelicoverpa armigera (Hübner) were studied in the last instar larvae by phase contrast microscopy to investigate the differences among 14 populations, collected from ten locations, spread over a distance of approximately 3000 km in six different states of India. The cluster analysis of differential hemocytes showed as many as 11 clusters of populations at 5% and six clusters at 10% homogeneity level. The cluster analysis of hemocytes of seven populations from cotton crops showed five and three clusters at 5% and 10% homogeneity levels, respectively. Diversity of hemocytes of four populations from chickpea was wider than that from cotton. The differences in hemocytes of various populations may be due to space, time, host plant, insecticide use, other agroecological conditions, and insect genetic variabilityper se. The field populations ofH. armigera heavily treated with insecticides appeared to contain more spherulocytes at the expense of plasmatocytes and granulocytes. The treatment of 6-day-old larvae ofH. armigera with cypermethrin decreased plasmatocytes and granulocytes, and increased prohemocytes and spherulocytes in the hemolymph of last instar larvae. Thus, differential hemocyte counts may serve as an indicator of insecticide exposure and the diversity of insect populations. http://www.phytoparasitica.org posting Dec. 20, 2004.     

Angioinvasive lymphoma (lymphomatoid granulomatosis) in a cat,with cutaneous and ocular metastasis

Lymphomatoid granulomatosis (LYG) is a rare variant of an angioinvasive T-cell lymphoproliferative disorder that primarily affects the lungs, with common sites of metastasis including the skin and subcutis. In humans, it is a B-cell lymphoproliferative disorder associated with Epstein-Barr virus infection. Our case is a 7-y-old, spayed female, domestic longhair cat that decompensated and was euthanized following an initial diagnosis of angioinvasive lymphoma from a skin biopsy. Autopsy revealed nodules in the lungs and subcutis, and corneal thickening and cloudiness. Histologic examination of cutaneous nodules, lungs, and eye showed similar angioinvasive cellular infiltrates and pattern to that of the original skin biopsy, consistent with a diagnosis of LYG. The neoplastic cells displayed CD3-positive immunoreactivity in the skin, eye, and lung, and PCR for antigen receptor rearrangement (PARR) showed T-cell clonality in all tissues tested. This is the third case of LYG to be reported in cats and is the only case in which PARR analysis and immunophenotyping immunohistochemical staining was performed. LYG with ocular involvement has not been reported previously in cats, to our knowledge. Our case demonstrates the necessity for considering LYG when presented with a cat with respiratory signs in conjunction with subcutaneous nodules and ocular lesions.     

Draft Genome Sequencing of <Emphasis Type="Italic">Rhizoctonia solani</Emphasis> Anastomosis Group 3 (AG3- PT) Causing Stem Canker and Black Scurf of Potato

Rhizoctonia solani is a soil-borne basidiomycete fungus with a necrotrophic lifestyle being classified into fourteen reproductively incompatible anastomosis groups (AGs). AG3-PT (a potato subgroup) is associated with quantitative and qualitative yield losses through stem canker and black scurf in potato. Here we present the first draft sequence of the R. solani [AG3-PT] strain RS-20 with a G-C content of 48.3%. It consists of 11,431 total predicted protein coding regions including 181 tRNA and 31 rRNA coding genes. The initial pBLAST revealed more than 97% hits among AG groups where as only 1.7% of genes hit with other organisms. The R. solani genome is found to be dominated with tri mer repeats. The genome-wide evolutionary studies revealed the close association of AG3-PT with AG3. The draft sequence represents a helpful resource not only for understanding the core genes involved in pathogenecity but also evolution and adaptive behaviour within the R. solani species complex.