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221.
The possibility for the combined control of Ophiostoma novo-ulmi and Scolytus multistriatus was tested in Italy. Two elm clones [U. pumila × U. minor (clone B) and U. glabra var. pendula grafted onto U. pumila × U. minor pollards (clone A)] were treated by stem injection of different blend or concentrations of fungicides and insecticides. Then, adults of S. multistriatus, either loaded with spores of two isolates of O. novo-ulmi (H328 and 182) or provided of their natural load of conidia, were forced to feed in twig crotches of the treated trees. After 48 hours all insects were checked (dead or alive). One month later, the same twigs were cut off and brought to the laboratory. From each twig, three discs almost 1mm thick were then taken (0, 3 and 6cm over the point where the insect fed). The wood discs were inoculated in selective substrate and stored until the development of O.novo-ulmi colonies. All thesis containing insecticides give good results against S. multistriatus. Similarly, all thesis containing fungicides show a good fungus control independently from the fungal isolated. The percentage of fungal transmission obtained from insects carrying the natural load of conidia was lower than percentages obtained from beetles artificially loaded. Both beetle sex and position on the foliage never influence insect mortality or O. novo-ulmi infection. The best results were obtained injecting the Carbendazim+Acephate blend in the clone A. High chemical concentrations did not improve the general results.  相似文献   
222.
ABSTRACT Tomato hybrids obtained from homozygous progeny of line 30-4, engineered for Tomato spotted wilt virus (TSWV) resistance, were tested under field conditions in two locations with their corresponding nontransgenic hybrids. No transgenic hybrid became infected, but 33 to 50% of plants of each nontransgenic hybrid became infected with a severe reduction of marketable fruit production. The transgenic hybrids conformed to the standard agronomic characteristics of the corresponding nontransgenic ones. Fruit were collected from the nontransgenic plots included in the experimental field and from border rows, and seed were used to estimate the flow of the transgene via pollen. No transgene flow was detected in the protected crops; however, in the open field experiment, 0.32% of tomato seedlings were found to contain the genetic modification. Immunity to TSWV infection in 30-4 hybrids was confirmed in laboratory conditions using mechanical inoculation and grafting. Thrips inoculation in leaf discs of line 30-4 demonstrated that TSWV replication was inhibited at the primary infection site but not in leaf discs of a commercial hybrid containing the naturally occurring resistance gene Sw-5. Due to the high economic value of tomato crops worldwide and the importance of TSWV, the engineered resistance described here is of practical value for breeding into cultivars of commercial interest, because it could be combined with naturally occurring resistance, thus greatly reducing the ability of the virus to develop resistance-breaking strains.  相似文献   
223.
Histologic and morphometric alterations in the parotid salivary gland of 14 male Gyr Zebu were carried out coupled with a histochemical study of the mucosubstance of this gland. Animals ranging in age from 1–2 months to 17–21 months were utilized. The gland was found to represent a compound tubular gland which is entirely serous in older animals, but with mucous endpieces in younger animals. The morphologic and morphometric data indicate that this gland reaches anatomic maturity at about 13 months of age, an age which correlates with the onset of spermatogenesis in this species. The histochemical nature of secretions is discussed for various components of the gland.  相似文献   
224.
This report describes an unusual computed tomographic (CT) hepatic pattern, characterized by negative attenuation values (from –19.59 to –28.85 Hounsfield Units, HU) in a canine patient with severe Cushing's syndrome. Attenuation values of the splenic parenchyma (63.26 HU) and abdominal fat (–118.34 HU) were within normal limits. The negative hepatic attenuation values allowed a CT diagnosis of severe hepatic fatty infiltration that was subsequently confirmed by tissue‐core biopsy and histopathological examination.  相似文献   
225.
Haemangiopericytoma is a soft tissue sarcoma believed to originate from pericytes. These tumours are commonly located on the skin and subcutaneous tissue of dogs and are most commonly found on the limbs. To the authors' knowledge, primary lung haemangiopericytomas have not been previously described in dogs. This case report describes the diagnostic evaluation and treatment of a primary haemangiopericytoma of the lung in a 10-year-old male, neutered, Siberian husky dog. Staging of the tumour was performed using a computed tomography scan of the thorax and a computed tomography-guided fine-needle aspiration biopsy of the lesion. Treatment was a right caudal lobectomy from a right lateral approach. No regional lymph node changes were noted on computed tomography or intraoperative assessments. Histopathology confirmed a spindle cell tumour that stained positive for vimentin and negative for desmin and S-100.  相似文献   
226.
In dogs, surgical removal of plant awns causing a foreign body granuloma or abscess may be challenging. The inability to localize the foreign body during surgical removal often leads to abscess recurrence. In this report, we describe ultrasound-guided retrieval as an alternative to standard surgical retrieval in animals where the plant awn can be identified sonographically. This procedure was used in six dogs with a superficial abscess due to a plant awn, and in all dogs the foreign body was successfully retrieved with Hartmann forceps. No complication was observed and no abscess recurred. Minimally invasive ultrasound-guided plant awn retrieval appears to be a safe effective method of retrieving superficially located plant awns in the dog.  相似文献   
227.
Bovine viral diarrhea virus 2 (BVDV-2) strains demonstrated in cattle, sheep, and adventitious contaminants of biological products have been evaluated by the palindromic nucleotide substitutions (PNS) method at the three variable loci (V1, V2 and V3) in the 5' untranslated region (UTR), to determine their taxonomical status. Variation in conserved genomic sequences was used as parameter for epidemiological evaluation of the species in relation with geographical distribution, animal host and virulence. Four genotypes, BVDV-2a, BVDV-2b, BVDV-2c, and BVDV-2d have been identified within the species. Taxonomical segregation corresponded to geographical distribution of genotype variants. Genotype 2a was present worldwide, and was the only circulating also in sheep, in addition to cattle. Genotypes 2b, 2c and 2d were restricted to South America. Contamination of biological products was related to genotypes 2a and 2d. Genetic variation could be related with chronological diffusion of the BVDV-2 species variants in different geographic areas. Chronologically, the species emerged in North America in 1978, spreading in UK and Japan, continental Europe, South America and New Zealand. Correlation between clinical features related with isolation of BVDV-2 strains and genetic variation indicated that subgenotype 1, variant 4 of genotype 2a was related with hemorrhagic syndrome. These observations suggest that evaluation of genomic secondary structure, by identifying markers for expression of virus biological activities and species evolutionary history, may be applied as useful tool for epidemiological evaluation of the BVDV-2 species, and possibly for other species of the genus Pestivirus.  相似文献   
228.
The aim of our work was to study the feasibility of using dual-energy X-ray absorptiometry to obtain reference bone density values in relation to body weight, gender, and metabolic bone disease in the green iguana. The study was performed on 28 animals. The weight, age, and gender of each iguana were recorded. Each lizard was carefully examined and radiographed to detect signs of metabolic bone disease. Blood samples were collected from each animal to evaluate Ca/P and total protein. All animals, both affected (group B; n = 11) and unaffected (group A; n = 17) by metabolic bone disease, were individually scanned using an X-ray densitometer. The regions of interest were the head, lumbar spine, right, and left femur. Statistical analysis was performed separately for each region of interest. Body weight had the strongest relationship with bone density (P < 0.01). Within regions of interest, for iguanas of average weight (710 g), statistically significant differences between healthy and sick animals were found: head (0.140 vs. 0.090 g/cm2; P < 0.01); lumbar spine (0.164 vs. 0.107 g/cm2; P < 0.01); right femur (0.103 vs. 0.076 g/cm2; P < 0.01); left femur (0.103 vs. 0.078 g/cm2; P < 0.01). Regression equations to obtain reference values of bone density as a function of body weight for animals affected and not affected by metabolic bone disease are provided. Our data indicate that X-ray bone densitometry is an additional tool for studying bone pathophysiology in reptiles.  相似文献   
229.

BACKGROUND

Chemical products against fungi and oomycetes pose serious environmental issues. In the last decade, the use of less impacting active ingredients was encouraged to reduce chemical inputs in viticulture. In this study, the effect of different antifungal compounds on grapevine agronomic, physiological, and molecular responses in the vineyard was evaluated in addition to protection against powdery and downy mildews.

RESULTS

In 2 years and in two Vitis vinifera cultivars (Nebbiolo and Arneis), a conventional crop protection approach, based on traditional fungicides (sulfur and copper), was compared to combined strategies. A well-known resistance inducer (potassium phosphonate), Bacillus pumilus strain QST 2808 and calcium oxide, both active ingredients whose biological interaction with grapevine is poorly characterized, were applied in the combined strategies in association with chemical fungicides. Despite a genotype effect occurred, all treatments optimally controlled powdery and downy mildews, with minimal variations in physiological and molecular responses. Gas exchange, chlorophyll content and photosystem II efficiency increased in treated plants at the end of season, along with a slight improvement in the agronomic performances, and an activation of molecular defense processes linked to stilbene and jasmonate pathways.

CONCLUSION

The disease control strategies based on potassium phosphonate, Bacillus pumilus strain QST 2808 or calcium oxide combined with traditional chemical compounds did not cause severe limitations in plant ecophysiology, grape quality, and productive yields. The combination of potassium phosphonate and calcium oxide with traditional fungicides can represent a valuable strategy for reducing copper and sulfur inputs in the vineyards, including those organically managed. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
230.
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