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1.
New Forests - Adventitious rooting (AR) is an obligatory step for vegetative propagation of commercial woody species. Paper industries have interest in Eucalyptus globulus Labill and its hybrids...  相似文献   
2.
A mechanistic model called PLASMO was developed earlier to simulate grapevine downy mildew (Plasmopara viticola) and has been applied in several viticultural areas of Italy since 1988 by the collaboration of several research institutions of Firenze. In this study, a new simulation model based on fuzzy logic has been developed for the same structure (biological cycle of P. viticola). This approach allows classical quantitative information to be used together with qualitative information. Vague concepts can also be handled. Agrometeorological data is used, with an hourly time step, starting from budbreak to the end of the growing season. Air temperature, relative humidity, rainfall and leaf wetness are required. The simulated processes are the growth of grapevine leaf area and the main phases of the biological cycle of the pathogen: incubation, sporulation, germination, spore survival and inoculation. The main epidemiological outputs are timing of infection events and disease intensity. The performance of the model is evaluated and the mechanistic and fuzzy logic approaches are compared.  相似文献   
3.

BACKGROUND

Sublethal effects of insecticides may negatively affect several biological and behavioral traits of insects. The lethal effects of pirimiphos-methyl and chlorfenapyr have been previously showed on Trogoderma granarium, but little knowledge is available about their sublethal effects at low concentrations on both sexes. Herein, the sublethal effects of pirimiphos-methyl and chlorfenapyr on the mobility of T. granarium males and females were investigated.

RESULTS

Lethal concentration (LC) values of pirimiphos-methyl and chlorfenapyr were lower for T. granarium females than males. LC values on males were LC10 = 0.000788 and 0.00139 mg active ingredient (a.i.) cm−2, LC30 = 0.00350 and 0.00535 mg a.i. cm−2, and LC50 = 0.00986 and 0.0136 mg a.i. cm−2 for pirimiphos-methyl and chlorfenapyr respectively. LC on females were LC10 = 0.000704 and 0.00110 mg a.i. cm−2, LC30 = 0.00323 and 0.00428 mg a.i. cm−2, and LC50 = 0.00925 and 0.0110 mg a.i. cm−2 for pirimiphos-methyl and chlorfenapyr respectively. The walking duration of beetles exposed to LC30 of pirimiphos-methyl was significantly lower than the individuals exposed to LC10 and LC30 of both insecticides and control ones. Pirimiphos-methyl LC30-exposed males remained more time on their back (101.7 s) than females (46.9 s), while the latter stayed immobile longer than males (381.7 s versus 371.9 s). The highest speed was recorded for control beetles (14.17 mm s−1 females vs. 12.44 mm s−1 males), while the lowest speed was observed in pirimiphos-methyl LC30-treated males (8.36 mm s−1) and females (9.66 mm s−1).

CONCLUSIONS

Overall, males and females exposed to low concentrations of pirimiphos-methyl and chlorfenapyr showed reduced motility. This knowledge can be exploited further to unlock behavioral effects of insecticides for effective pest management programs in warehouses. © 2023 Society of Chemical Industry.  相似文献   
4.
The RAPD fingerprinting procedure was used in combination with pathogenicity assays on differential cultivars to characterize a representative collection of 72 Fusarium spp. isolates of different geographic origin collected from diseased carnation. In F. oxysporum f. sp. dianthi, isolates were grouped according to the physiologic race: group 1 included isolates of race 4; group 2 was formed by isolates of race 2 and single representatives of races 5 and 6; group 3 included isolates of races 1 and 8. No correlation was found between RAPD data and geographic origin of the isolates tested: representatives of race 2 isolated in Italy, Israel and Japan had the same amplification profile. Three isolates which showed a low level of pathogenicity on all carnation cultivars tested shared an identical amplification pattern and are probably saprophytic F. oxysporum. Finally, two F. redolens isolates from Japan and seven non-pathogenic isolates of F. proliferatum collected from diseased carnation in Italy, Israel and The Netherlands were clearly distinguishable according to their RAPD fingerprint. The results are discussed in relation to previous studies on the genetic diversity of F. oxysporum f. sp. dianthi and to the development of forma specialis- and pathotype-specific diagnostic tools.  相似文献   
5.
The pathogenicity of four isolates ofFusarium oxysporum obtained from infected cultivated rocket (Eruca vesicaria) and wild (sand) rocket (Diplotaxis tenuifolia) was tested on the following cruciferous hosts: stock, radish, wild and cultivated rockets, and various species in the cabbage tribe: cabbage (Brassica oleracea var.sabauda), cauliflower (Brassica oleracea var.botrytis), Brussels sprouts (Brassica oleracea var.gemmifera), broccoli (Brassica oleracea var.italica), turnip (Brassica rapa var.rapa). The results indicated that isolates ofF. oxysporum from cultivated and wild rocket belong to theforma specialis raphani. The isolates from rocket were pathogenic on cabbage, Brussels sprouts, broccoli, turnip, radish and stock; isolates ofF. oxysporum conglutinans from cabbage and radish, and the isolate ofF. oxysporum f.sp.raphani from rape obtained from the ATCC collection, were pathogenic on both cultivated and wild rocket.  相似文献   
6.

Background

The authors report the first case of feline gastric actinomycosis associated with infection by Actinomyces hordeovulneris.

Case presentation

A 4-year-old, neutered male, semi-feral European cat, with a 1 year history of chronic vomiting, was referred to the clinic. Abdominal ultrasound examination identified a hypoechoic focal transmural thickening with loss of normal wall layering and hyperechoic speckles at the gastric body. Initial gastroscopic examination showed a tumour-like gastric mass with an ulcerated depression at the level of the greater curvature. Histologic examination of endoscopic biopsy specimens was consistent with a severe lymphoplasmacytic gastritis. After 2 months, due to persistence of abdominal discomfort, surgical exploration and intraoperative sampling of gross abnormalities was recommended. Full thickness gastric wall biopsies, and fine needle aspiration of the gastric thickening and gastric lymph node, were performed. Histopathological examination identified a transmural pyogranulomatous gastritis. Aspirate samples of the gastric wall cultured positive, with colony morphology, biochemical testing and PCR of the 16 s rRNA gene compatible with Actinomyces hordeovulneris. After 4 months of treatment with cefovecin (8 mg/kg subcutaneously every 14 days), the vomiting completely resolved, as well as the ultrasonographic gastric alteration.

Conclusion

This case report of feline gastric actinomycosis, caused by Actinomyces hordeovulneris, suggests that gastric bacterial infection should be considered in cases of focal gastric wall thickening associated with chronic vomiting in the cat, which may otherwise closely resemble neoplastic disease. Once a diagnosis of actinomycosis was obtained, a correct treatment with antibiotic therapy can resolve it.
  相似文献   
7.
In this paper lipoxygenase (LOX) presence was investigated in coffee berries to determine its involvement in lipid degradative metabolism of plants grown in organic and conventional cultivations. An immunochemical analysis has evidenced a ca. 80 kDa protein, cross-reacting with an anti-LOX antibody, only in the pulp fraction of berries obtained from plants of both cultivations. LOX activity in this fraction could be monitored either as conjugated diene formation or reaction products (determined by HPLC) and was mainly associated with a heavy membrane fraction (HMF, enriched in tonoplast, endoplasmic reticulum, plasma membrane, and mitochondria) and a light membrane fraction (LMF, enriched in plasma membrane and endoplasmic reticulum, with low levels of tonoplast and mitochondria). The LOX activity of LMF from berries of both cultivations showed an optimum at pH 8.0. The HMF exhibited a different activity peak in samples from conventional (pH 8.0) and organic (pH 5.5) cultures, suggesting the presence of different isoenzymes. These findings were also confirmed by variation of the ratio of 9- and 13-hydroperoxides in organic (1:1) and conventional cultivations (1:10), indicating that the organic one was subjected to an oxidative stress in the coffee pulp fraction leading to the expression of an acidic LOX. Such de novo synthesized LOX activity could be responsible for the production of secondary metabolites, which may interfere with the organoleptic profile of coffee.  相似文献   
8.
The aim of the present study was to evaluate the effect of trace mineral nutrition on sow performance, mineral content, and intestinal gene expression of neonate piglets when inorganic mineral sources (ITM) were partially replaced by their organic mineral (OTM) counterparts. At 35 d postmating, under commercial conditions, a total of 240 hyperprolific multiparous sows were allocated into three experimental diets: 1) ITM: with Zn, Cu, and Mn at 80, 15, and 60 mg/kg, respectively; 2) partial replacement trace mineral source (Replace): with a 30 % replacement of ITM by OTM, resulting in ITM + OTM supplementation of Zn (56 + 24 mg/kg), Cu (10.5 + 4.5 mg/kg), and Mn (42 + 18 mg/kg); and 3) Reduce and replace mineral source (R&R): reducing a 50% of the ITM source of Zn (40 + 24 mg/kg), Cu (7.5 + 4.5 mg/kg), and Mn (30 + 18 mg/kg). At farrowing, 40 piglets were selected, based on birth weight (light: <800 g, and average: >1,200 g), for sampling. Since the present study aimed to reflect results under commercial conditions, it was difficult to get an equal parity number between the experimental diets. Overall, no differences between experimental diets on sow reproductive performance were observed. Light piglets had a lower mineral content (P < 0.05) and a downregulation of several genes (P < 0.10) involved in physiological functions compared with their average littermates. Neonate piglets born from Replace sows had an upregulation of genes involved in functions like immunity and gut barrier, compared with those born from ITM sows (P < 0.10), particularly in light piglets. In conclusion, the partial replacement of ITM by their OTM counterparts represents an alternative to the totally inorganic supplementation with improvements on neonate piglet gene expression, particularly in the smallest piglets of the litter. The lower trace mineral storage together with the greater downregulation of gut health genes exposed the immaturity and vulnerability of small piglets.  相似文献   
9.
This study reports the immunohistochemical localization and distribution of orexin A and B-like and their receptors-like peptides in the gastroenteric tract of chicken. The immunoreactivity is distributed in endocrine cells, nerve fibers and neurons, both in the stomach and intestine, and shows a discrete conformity with the data till now reported for Mammals. Our study suggests a possible participation of orexin-like peptides in the modulation of chicken gastroenteric activities and the preservation of their main distribution compared to Mammals. Western blot analysis has confirmed the presence of prepro-orexin and both receptors in the examined tissues.  相似文献   
10.
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