Effect of fungal pathogens on digestibility and chemical composition of Italian ryegrass (Lolium multiflorum) and tall fescue (Festuca arundinacea)

Slight infection by Drechslera siccans or Rhynchosporium spp. significantly reduced in vitro dry matter digestibility, water-soluble carbohydrate and the total amino acid content of Italian ryegrass (Lolium multiflorum) foliage. The concentration of all 15 amino acids detected was reduced, with arginine reduced significantly more than the others. Total nitrogen was either increased or not changed, and the amino acid composition was not altered. Limited work with Drechslera festucae on tall fescue (Festuca arundinacea) gave similar results. Small samples of healthy and diseased grass leaves at three different physiological stages were used to detect these changes.
Limited leaf spotting by D. siccans caused metabolic changes of the same magnitude as extensive leaf blotching by Rhynchosporium. Impaired photosynthesis and growth of the fungi within the leaf tissues are possible causes of these changes. Decreased digestibility and increased dry matter content of diseased grass foliage could be of great practical importance.     

IMAGING DIAGNOSIS—METASTATIC ADRENAL PHEOCHROMOCYTOMA IN A DOG

A 10‐year‐old Akita mix became acutely paraplegic. Upon magnetic resonance imaging, multiple, slightly T2‐hyperintense, T1‐isointense extradural masses, relative to spinal cord were found in the vertebral canal. The retroperitoneal masses had mixed T2‐signal intensity. The contrast enhancement pattern for the spinal masses was both homogenous and heterogenous. The diagnosis was metastatic pheochromocytoma. Signal intensity of the tumors in this dog was similar to reports of pheochromocytoma in human beings.     

A survey of ryegrass swards for the presence of fungal pathogens in relation to management

Surveys of perennial and Italian ryegrass swards (Lolium perenne L. and L. multiflorum Lam.) at regular intervals in 1977 and 1978 in Berkshire, Wales and Devon confirmed that leaf infection by Drechslera spp. was the most frequently occurring foliar fungal disease. Rhynchosporium spp. and Puccinia coronata Corda were also recorded but in contrast to Drechslera spp., which caused damage throughout the year, attacks by these two fungi were only sporadic.
The incidence of Drechslera was greater in 1977 than in 1978 and was greater in Berkshire where most fields were infected in both years than in Wales and Devon. Both perennial and Italian ryegrasses were infected. The number of leaves damaged increased with leaf age. Damage was greater on fields managed for conservation than those which were grazed. Infection increased from February onwards and was greatest in autumn. It is concluded that Drechslera might be controlled by removing infected herbage in autumn by cutting.
Rhynchosporium spp. were prevalent only in Berkshire and more Italian ryegrass fields ( ca , 50%) were infected than perennial ryegrass fields ( ca , 10%). Infection was confined to the period March to May. This pathogen caused more leaf area damage than Drechslera .
Puccinia coronata occurred only once in Devon and Wales. In Berkshire incidence was confined to 1978 and was common from September to November, when 60–70% of both Italian and perennial ryegrass fields were infected. Some difference between perennial ryegrass cultivars was observed.     

大豆新品种陇黄2号选育报告

陇黄2号是由甘肃省农业科学院旱地农业研究所和农业生物技术国家重点实验室(香港中文大学)于2008年从山西省农业科学院经济作物研究所引进的以晋豆23为母本、鲁豆4号为父本常规杂交的F3代群体中,采用系谱法选育而成的大豆新品种。2013 — 2014年参加甘肃省大豆品种(系)区域试验,2 a 10点(次)平均折合产量为2 572.28 kg/hm2,比对照品种陇豆2号平均增产9.17%。2015 年参加甘肃省大豆品种(系)生产试验,平均折合产量2 501.70 kg/hm2,比对照品种陇豆2号增产6.09%。陇黄2号田间表现高抗花叶病毒病和大豆黑斑病。籽粒含粗蛋白(干基)385.3 g/kg、粗脂肪(干基)204.2 g/kg,品质优良。陇黄2号适用于机械化作业的间套作带状复合种植。该品种适宜在甘肃省河西灌区、中部沿黄灌区、陇东旱塬区及生态条件相近地区种植。     

Radar detection of the nucleus and coma of comet hyakutake

Radar observations of comet Hyakutake (C/1996 B2) made at the Goldstone Deep Space Communications Complex in California have detected echoes from the nucleus and from large grains in the inner coma. The nucleus of this bright comet was estimated to be only 2 to 3 kilometers in diameter. Models of the coma echo indicate backscatter from porous, centimeter-size grains ejected anisotropically at velocities of tens of meters per second. The radar observations suggest that a comet's activity may be a poor indicator of its size and provide evidence that large grains constitute an important component of the mass loss from a typical active comet.     

Effects of nitrogen and potassium fertilizer application on Drechslera spp. and Puccinia coronata on perennial ryegrass (Lolium perenne) foliage

In a field experiment nitrogen (N) fertilizer was applied to small plots of perennial ryegrass ( Lolium perenne ) at rates equivalent to 0, 200, 400 and 600 kg N/ha/yr at each of two levels of potassium (K) 0 and 200 kg K/ha/yr. Plots were cut at 6-week intervals during 1977–79 and dry matter yield was determined. Water-soluble carbohydrate and N content of the foliage were measured at three harvests in 1977. The incidence and severity of Drechslera spp. were assessed at and between harvests; attack by Puccinia coronata was assessed each autumn. Most foliar damage was caused by Drechslera spp. This was increased by N application which also altered the relative proportions of the Drechslera spp. present. K application had no apparent effect on disease incidence. Puccinia coronata was more prevalent on older leaves and on one occasion its incidence was increased by N application.     

RADIOGRAPHIC AND COMPUTED TOMOGRAPHY FINDINGS IN BELGIAN SHEPHERD DOGS WITH MILD ELBOW DYSPLASIA

We compared computed tomography (CT) and radiographic findings of Belgian shepherds with grade 1 or borderline elbow dysplasia to determine whether the radiopaque area dorsal to the anconeal process and seen in mediolateral 45° flexed radiographs is formed by osteophytes, or whether it is an anatomic variation. Eighteen dogs with screening results 0/1, 1/0, or one or both elbows graded as borderline were studied. The radiographs were evaluated according to International Elbow Working Group guidelines and compared with CT images. A fragmented medial coronoid process was seen in five joints, and remaining 31 joints were considered free of dysplasia based on CT images. In radiographs, height of the radiopaque area on the anconeal process was 0–2.7 mm in dysplastic and 0–3.0 mm in other joints. Sensitivity of this sign as dysplasia indicator was 40% and specificity 29%. All dysplastic joints and three of the other joints had blurring of the cranial edge of the medial coronoid process. Subtrochlear sclerosis was seen in four dysplastic joints and in three other joints. Both changes were significant indicators of dysplasia ( P <0.001). Sensitivity and specificity of these phenomena as dysplasia indicators were 80% and 90%, respectively. We conclude that the radiopaque area on the anconeal process might not always be osteophyte formation in Belgian shepherds and should not be used as the sole criterion for dysplasia. Blurring of the medial coronoid process cranial edge and ulnar trochlear notch sclerosis are reliable signs of elbow dysplasia and may be beneficial in screening protocols.     

MAJOR PATHWAYS FOR NITROGEN REMOVAL IN WASTE WATER STABILIZATION PONDS

A study on the factors influencing nitrogen removal in waste water stabilization ponds was undertaken in an eight-pond series in Werribee, Australia. Nitrogen species including Kjeldahl nitrogen, total ammonia nitrogen, nitrite and nitrate were monitored monthly from March 1993 to January 1994. At the same time, pH, temperature, chlorophylla content and dissolved oxygen were also recorded. Highest nitrogen removal occurred during the period with highest levels of chlorophylla content and dissolved oxygen, but the rate of nitrogen removal was not related to temperature and pH. Enhanced photosynthetic activities resulting from an increased phytoplankton abundance due to prolonged detention time caused an increase in dissolved oxygen, and created an optimum condition for nitrification to occur. In this process, ammonia was oxidized to nitrite and nitrate which were subsequently reduced to elemental nitrogen. Apart from nitrification-denitrification which was the major nitrogen removal pathway in the study system, algal uptake of ammonium, nitrate and nitrite as nutrient sources also contributed to the nitrogen removal. The role of phytoplankton and zooplankton in the treatment process in waste stabilization ponds was discussed.     

MAGNETIC RESONANCE IMAGING FEATURES OF INTRACRANIAL ASTROCYTOMAS AND OLIGODENDROGLIOMAS IN DOGS

Astrocytomas and oligodendrogliomas represent one third of histologically confirmed canine brain tumors. Our purpose was to describe the magnetic resonance (MR) imaging features of histologically confirmed canine intracranial astrocytomas and oligodendrogliomas and to examine for MR features that differentiate these tumor types. Thirty animals with confirmed astrocytoma (14) or oligodendroglioma (16) were studied. All oligodendrogliomas and 12 astrocytomas were located in the cerebrum or thalamus, with the remainder of astrocytomas in the cerebellum or caudal brainstem. Most (27/30) tumors were associated with both gray and white matter. The signal characteristics of both tumor types were hypointense on T1‐weighted images (12 each) and hyperintense on T2‐weighted images (11/14 astrocytomas, 12/16 oligodendrogliomas). For astrocytomas and oligodendrogliomas, respectively, common findings were contrast enhancement (10/13, 11/15), ring‐like contrast enhancement (6/10, 9/11), cystic regions within the mass (7/14, 12/16), and hemorrhage (4/14, 6/16). Oligodendrogliomas were significantly more likely to contact the brain surface (meninges) than astrocytomas (14/16, 7/14, respectively, P=0.046). Contact with the lateral ventricle was the most common finding, occurring in 13/14 astrocytomas and 14/16 oligodendrogliomas. No MR features were identified that reliably distinguished between these two tumor types. Contrast enhancement was more common in high‐grade tumors (III or IV) than low‐grade tumors (II, P=0.008).