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The article reports that Glomerella miyabeana was the causal agent of two new diseases that have been observed attacking willows in New Zealand. One and two year-old willows growing in the Aokautere Research Nursery infected with Glomerella miyabeana exhibited stem lesions and leaf spots. Willows in the willow collection kept at the Aokautere Research Nursery were examined closely throughout the growing season for stern lesions, leaf spotting and defoliation. study showed that black stem cankers and leaf spotting and defoliation of willows in New Zealand were caused by the same fungus, Glomerella miyabeana.

An ultrastructural study of basidial and basidiospore development of Chondrostereum purpureum was conducted. Also, sporophore rehydration and basidiospore release in the field were studied. New basidia arose sympodially and expanded by enteroblastic extension. Basidia were always delimited by a primary septum with a septal pore apparatus which was sealed by overgrowth on breakdown of the basidium following basidiospore discharge. Basidia were initially binucleate and following karyogamy and meiosis four daughter nuclei formed, each entering a basidiospore initial. Basidial walls were inconspicuously bilayered and sterigmata arose by extension of the innermost wall layer. Basidiospore initials developed on the top of sterigmata and contained numerous cytoplasmic vesicles in their apices. Basidiospore initials were delimited from sterigmata by formation of an electron-lucent zone, often leaving a portion of the sterigmal wall attached to the base of the basidiospore. Sporophores and basidia survived air drying to a water content of 22 % by vacuolation and condensation of cytoplasm. Sporophores absorbed moisture rapidly and were fully hydrated (80 % water content) less than 10 minutes following soaking. Within two hours of hydration most vacuoles had disappeared from the cytoplasm of basidia. There was a delay of several hours following hydration until significant numbers of basidiospores were formed and released. Field studies confirmed this delay and showed that rainfall was essential for basidiospore release. Basidiospore release was sustained by high (>75 %) levels of relative humidity. [ABSTRACT FROM AUTHOR]

Microconidia of M. brunnea were induced in the laboratory on 15% V8 juice agar and poplar leaf discs. Apothecia of Drepanopeziza tremulae and stromata containing conidia were formed on naturally infected leaves and leaf-discs. The influence of temperature on apothecial development was investigated. The morphology of apothecia and stromata is described. [ABSTRACT FROM AUTHOR]

Studies on the pathogenesis of Marssonina brunnea, M. castagnei and M. populito susceptible poplars showed that germtubes penetrated poplar leaves directly by enzymatic activity and indirectly through stomata. Six days following inoculation, hyphae had ramified throughout palisade and mesophyll tissues causing penetrated cells to become moribund. Acervuli were formed within seven days of inoculation and conidia were released by rupture of the cuticle and upper epidermal wall. [ABSTRACT FROM AUTHOR]

Roots of red clover seedlings grown on plates of water agar, or water agar containing benomyl or prochloraz, were inoculated with conidia of Trichocladium basicola and examined by light and transmission electron microscopy. Penetration of host epidermal cells occurred from about 16 h after inoculation of untreated or fungicide-treated seedlings. Intracellular hyphae were constricted at septa and had a beaded appearance. They invaginated the host plasmalenima, but had no obvious deleterious effect on the cytoplasm until they had grown to fill much of the lumen, when host cells degenerated and died. As colonization of the cortex progressed, straight, unconstricted hyphae were formed and from these reproductive hyphae developed, which produced endoconidiophores and chlamydospores on the root surface. Penetration of host cell walls appeared to involve localized action of fungal enzymes. Papillae were often found at sites of penetration, but these rarely obstructed fungal development. Seedlings treated with prochloraz had fewer sites of fungal penetration, and fewer cells in the beaded hyphae than untreated seedlings or those treated with benomyl. Both fungicides caused abnormalities in fungal ultrastructure. Hyphae treated with benomyl were often found to contain lomasomes, while those treated with prochloraz had thickened, fragmented walls, and disorganized cell contents. [ABSTRACT FROM AUTHOR]

Aim: To describe the histopathology of a previously unrecorded canine disease and deduce the cause of the lesions., Methods: Formalin-fixed tissues were processed into paraffin wax and epoxy resin for light and electron microscopy of variously stained sections of liver, brain, heart muscle and kidney., Results: Periodic acid Schiff (PAS) -positive bodies in liver and myocardium were typical of a polyglucosan body disease. Neurons contained coarse granular material that stained similarly to the polyglucosan bodies., Conclusion: The nature, distribution and histochemistry of lesions observed are consistent with a putative diagnosis of Glycogen storage disease type IV, an inherited metabolic defect associated with a deficiency of glycogen-branching enzyme not previously reported in dogs.

In two of eight Hofmannophila pseudospretella specimens studied by microscopy, the larval midgut contained an unidentified micro-organism. Although not seen microscopically in midgut sections, bacteria were isolated from dissected midgut. Microscopy, carbohydrate utilization and ribosomal sequence data all separated the isolates into the same three classes. These were identified as Lactococcus lactis, Carnobacterium piscicola and, tentatively, Bacillus subtilis, the first two being facultative anaerobes and the latter, an aerobe. The bacteria were therefore not specifically adapted to the reducing conditions of the midgut.

Abstract The specialised histology and anatomy of the central nervous system (CNS) is reflected in its pathology. This is particularly so for the perivenular/periarterial spaces in which inflammatory cells accumulate in inflammation. These spaces, although structurally not lymphatics, act as lymphatics draining fluid from brain to subarachnoid space and to lymphatics draining to deep cervical lymph nodes. Inflammatory cells may enter or leave the CNS by this route. In immune-based inflammation, they are colonised by subsets of immune cells allowing the processing of antigen, synthesis of antibody and development of cell mediated immune reactions.

A severe anaemia was diagnosed in a 7-month-old female cat. Most erythrocytes contained unusually large Heinz bodies and showed marked distortion. Six weeks later, the cat had recovered from the anaemia, but the erythrocytes still contained smaller inclusions. By light microscopy, these inclusions did not stain as typical Heinz bodies, but, by electron microscopy, Heinz bodies and autophagocytic vacuoles were identified. It is suggested that this cat had a pre-existing defect in its haemoglobin which made it more susceptible to damage by an unknown oxidizing agent.

"Ball and socket"-like membrane processes interlock fiber cells in the sheep lens cortex, but appear reduced deeper in the lens. Wheat germ agglutinin (WGA) binds preferentially to these ball and socket structures, and more weakly to other membrane regions. On protein blots, 125I WGA binds to glycoproteins with 140,000 and 32,000 apparent molecular weight, the smaller protein also binding 125I fibronectin. In two animal cataract models, the intense WGA labeling of globular bodies replaces the spotty WGA staining pattern associated with the ball and sockets in the normal lens.