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31.
We investigated an Armillaria root disease centre in a 60‐year‐old, naturally regenerated Pinus sylvestris stand located at 1250 m altitude in Sinop province in northern Turkey. Based on sequence analysis of the internal transcribed spacer region of the rDNA, the mycelial fans sampled from the infected trees were Armillaria ostoyae. Multilocus genotyping indicated that the fans belonged to a single genet, at least 0.2 ha in size. Drought as a predisposing factor is discussed. The study area received 50–70 and 25–50% of the normal precipitation in May, June and August in 2009 and in August and September in 2010, respectively. Moreover, earlier excavation work to prepare a forest road had probably disrupted the water table in the affected stand. 相似文献
32.
Mélodie Schmitz Sébastien Baekelandt Lam Khoa Tran Thi Syaghalirwa N. M. Mandiki Jessica Douxfils Thinh Quoc Nguyen Huong Do Thi Thanh Patrick Kestemont 《Fish physiology and biochemistry》2017,43(1):39-49
In Vietnam, the production of striped catfish Pangasianodon hypophthalmus S. reached more than 1.2 millions of tons in 2014 and is mainly gathered in the Mekong Delta (South Vietnam). A survey was carried out during the dry season 2013 (March–April) and rainy season 2014 (July–August) in 12 fish farms of the lower (Tra Vinh Province) and higher (Can Tho Province) Mekong River Delta. This study allowed drawing up current key osmoregulatory and innate immune parameters of striped catfish in aquaculture depending on the geographical location, particularly the proximity to the River Mekong Estuary and the seasonal surface runoff. In the dry season, plasma osmolality was positively correlated with salinity. Gill Na+K+ ATPase dropped in the rainy season, while kidney Na+K+ ATPase remained stable. Abundance of immune blood cells, especially thrombocytes and monocytes, tended to increase in farms located in tidal area. Production of reactive oxygen species in the spleen, kidney lysozyme activity and plasma complement activity did not vary whatever the season or the proximity to the estuary. Plasma lysozyme activity was 50-fold higher than in kidney and increased in the rainy season as well as in tidal sites. Kidney complement activity decreased in the dry season, especially in tidal sites. In conclusion, regarding key osmoregulatory and immune factors, striped catfish farms located in the Mekong Delta may be affected by seasonal and regional salinity and runoff fluctuations. 相似文献
33.
A. Lehtijärvi F. Oskay H. T. Doğmuş Lehtijärvi A. G. Aday Kaya F. Pecori A. Santini S. Woodward 《Forest Pathology》2018,48(1)
Ceratocystis platani was detected at several locations in the European side of Istanbul, causing severe dieback and mortality, mainly on Platanus × acerifolia imported from Italy approximately 160 years ago, but also on Platanus orientalis. In the work reported here, the causal agent of the dieback and mortality was identified based on morphological characteristics in culture and internal transcribed spacer (ITS) sequencing, confirming the presence of C. platani in Turkey. All analysed C. platani isolates from Istanbul shared the same ITS sequence with European C. platani strains available in the NCBI, but differed from other species previously ascribed to the Ceratocystis fimbriata species complex. Pathogenicity of C. platani was proven by inoculation onto 25‐cm‐long and 4–9 mm diam. P. orientalis twigs and the causal agent reisolated from symptomatic tissues. In a survey of 976 Platanus in streets and parks of Istanbul, 26.5% of trees showed symptoms of C. platani infections, whilst 5.6% were dead. The proportion of symptomatic trees was higher where management interventions, such as topping or pruning and felling infected trees had been carried out. 相似文献
34.
A 16-wk growth trial was conducted to examine the effects of dietary replacement of fish meal by defatted soybean meal (SBM) and fermented soybean meal (FSBM) with taurine supplementation on growth performance, nutrient apparent digestibility coefficient (ADC) and biological parameters of pompano fish. The FSBM was produced by fermenting SBM with Lactobacillus spp. Seven isonitrogenous and isoenergetic diets were formulated to replace 35% or 50% of fish meal by SBM or FSBM with taurine supplementation. The diets are denoted as follows: FM, SBM35, SBM35T, FSBM35T, SBM50, SBM50T, and FSBM50T. The FM (the basal diet) contained fish meal as a main source of dietary protein. Taurine was supplemented to SBM35T, FSBM35T, SBM50T, and FSBM50T at the level of 15 g/kg diet. Pompano juveniles with an initial body weight (BW) of 80 g reared in floating net cages were fed the experimental diets twice daily for 16 wk. Results showed that the final BW, weight gain, and feed conversion ratio of fish fed SBM35 and SBM50 were significantly lower than those of fish fed FM (P < 0.05), indicating that the replacement of fish meal by SBM at the rate of 35% in the diet is excessive for pompano. Supplementation of taurine to the SBM-included diets significantly increased growth performance and feed utilization (P < 0.05); however, these diets did not restore the performance back to a level equivalent to that of fish offered the basal diet. Meanwhile, fish fed FSBM35T had comparable growth and feed performances to those fed FM. Hematocrit values, total biliary bile acid levels, whole body lipid contents, and tissue taurine concentrations of fish fed SBM35 and SBM50 were the lowest among the treatments, but these parameters were improved by taurine supplementation and FSBM inclusion in the diet. Taurine supplementation increased lipid ADC, and SBM fermentation slightly enhanced both lipid and protein ADCs of the fish. These findings suggest that the combination of FSBM and taurine supplementation is an effective way to improve growth performance, nutrient digestibility, and biological parameters, and that FSBM with taurine supplementation can replace 35% of fish meal in pompano diets without any negative effects on growth and feed performances in a long-term feeding period. 相似文献
35.
36.
Eun Ju Cho Do Jin Lee Chi Do Wee Hong Lim Kim Yong Hwa Cheong Ju Sik Cho Bo Kyoon Sohn 《Scientia Horticulturae》2009,122(4):633-637
We aimed to investigate the effects of inoculating Panax ginseng C.A. Meyer seedlings with arbuscular mycorrhizal fungi (AMF) by examining the root colonization, plant nutrition uptake, growth characteristics, and soil aggregation of P. ginseng seedlings inoculated at the time of transplantation. At 16 weeks, the AMF spore density per 30 g of fresh mycorrhizosphere in seedlings inoculated with AMF (AMF+ seedlings) was 256.8 and that in seedlings not inoculated with AMF (AMF− seedlings) was 186.3, respectively. The colonization rate of AMF in the lateral roots of AMF+ seedlings was approximately 19% higher than that in the lateral roots of AMF− seedlings. The patterns of AMF colonization in ginseng roots were similar to those of the Paris-type mycorrhizal association. Plant growth characteristics, such as plant height, root length, leaf area, number of lateral roots, fresh weight of shoots and roots, and chlorophyll content, were significantly enhanced in AMF+ seedlings compared to AMF− seedlings. The macronutrient content (P, K, and Ca) and micronutrient content (Cu, Fe, and Zn) of both shoots and roots were also significantly higher in AMF+ seedlings compared to AMF− seedlings. Furthermore, glomalin content and soil aggregation were significantly enhanced in AMF inoculated areas. Our results indicate that AMF inoculation may enhance the growth of ginseng seedlings by improving the uptake of mineral nutrients and the soil structure in mycorrhizosphere. 相似文献
37.
Da-Hee Jeong Sun-Hee Do Il-Hwa Hong Hai-Jie Yang Dong-Wei Yuan Dong-Hag Choi Kyu-Shik Jeong 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(4):401-403
A male, 5-year-old Jindo dog underwent enterectomy and enteroanastomosis due to ileus of the intestine at a local veterinary hospital. Grossly, the excised intestine showed markedly thickened multinodular masses in the serosal layer of the upper part, and soft-to-firm, cream-colored neoplastic masses that displayed extensive nodular mucosal protuberances into the lumen. The neoplastic masses were filled with large round cells that were ovoid in shape and they had pale and/or hyperchromatic nuclei. The neoplastic cells had mainly infiltrated into the mucosal and submucosal layers, and they had diffusely invaded the muscular and serosal layers. Therefore, the diagnosis of canine multiple intestinal malignant lymphomatous polyposis was made based on the gross and histopathological findings. The origin of these tumor cells was determined to be B-cells since they were positive for anti-CD20. 相似文献
38.
耐冷菌在低温下能通过诱导作用形成重金属的碳酸盐沉淀,在寒区重金属污染土壤修复方面具有重要的应用潜力,但目前缺乏对多种重金属污染土壤的修复及其稳定性的研究.试验研究了1株耐冷碳酸盐矿化菌(谷氨酸棒菌DC1)在低温条件下对土壤中4种重金属的固定作用及其稳定性.结果 表明:菌株DC1的发酵液可通过诱导作用将土壤中的可交换态C... 相似文献
39.
Tran Van Do Phung Dinh Trung Mamoru Yamamoto Osamu Kozan Nguyen Toan Thang Dang Van Thuyet 《Journal of Sustainable Forestry》2018,37(1):1-14
Forest ecosystems can modify the atmospheric CO2 through biomass accumulation mostly in tree stems with diameter at breast height (DBH) ≥ 10 cm. Aboveground biomass increment (ΔAGB), and changes in stand AGB, no. stems and basal area (BA) were calculated from mortality, recruitment, and growth data of tree stems in tropical evergreen broadleaved forest, Central Highland Vietnam. Data were derived from ten 1-ha permanent plots established in 2004, where all stems with DBH ≥ 10 cm were tagged, identified to species, and measured for DBH in 2004 and 2012. In an 8-year duration, the increment was 53 ± 10 stems ha–1, 7.8 ± 0.3 m2 ha–1 for BA and 86.0 ± 4.6 Mg ha–1 for AGB. The stem mortality rate was 0.9% year–1 and the stem recruitment rate was 2.2% year–1. Annual ΔAGB was 10.8 Mg ha–1 year–1, equaling to 5.4 Mg C ha–1 year–1. Of which, tree stems of 35–80 cm DBH classes accounted for 65%. The results indicated that the forest is in stage of carbon sequestration. Any disturbances causing death of 35–80 cm DBH tree stems will much reduce carbon sequestration capacity and it will take a long time for AGB to return to pre-disturbance stage. 相似文献
40.
Pil Birkefeldt Møller Pedersen Kasper Hansen Do Thi Thanh Houng Mark Bayley Tobias Wang 《Aquaculture Research》2014,45(3):427-438
The Asian swamp eel Monopterus albus is normally considered a freshwater species, but can also occasionally be found in brackish water. It is an obligate air‐breather with highly reduced gills, making its osmoregulation physiology interesting because the gills normally represent the primary site of osmoregulation in teleosts. Being a popular fish for human consumption, the swamp eel is cultured extensively in freshwater ponds in the Mekong Delta of Vietnam. However, very little is known about its salinity tolerance, which is becoming topical due to the increasing salt‐water intrusions into tropical deltas. We therefore studied how increased salinity affects survival, growth, blood pressure, heart rate, blood osmolality and plasma ions. All eels survived prolonged exposure to 5 and 10 g L?1, although plasma osmolality increased significantly at 10 g L?1. Further elevation to 15 and 20 g L?1 was associated with significantly elevated mortality, with a corresponding increase in plasma osmolality and ion con‐centrations. Our results show that swamp eels thrive in 0–10 g L?1 with an optimum growth between 0 and 9 g L?1, indicating that utilization of low saline brackish waters for aquaculture is possible. 相似文献