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41.
Milk vetch dwarf virus (MDV) is an important member of the genus Nanovirus and is transmitted by the aphid Aphis craccivora. MDV has multiple single-stranded DNA genome components, each approximately 1 kb, and two or three alpha-satellite molecules. It mainly infects plants of the legume family Fabaceae. Recently, papaya (Carica papaya) collected in Yesan, South Korea, displaying symptoms of leaf yellowing and dwarfism, was identified as a new host for MDV. To examine the geographical distribution of MDV, papaya samples with symptoms were harvested in South Korea, Vietnam, and Taiwan in August 2018, along with tomato and pepper samples grown in adjacent fields in Vietnam. The results revealed the presence of MDV not only in papaya but also in pepper and tomato. This MDV infection in members of the Solanaceae family was confirmed by Southern blot hybridization performed using a PCR product of segment S as a probe. Based on sequence analysis of three MDV components (M, S, and C3), we verified the presence of three different isolates of MDV in these three countries and homology between sequences of isolates from papaya and from members of the Solanaceae from Vietnam. Taken together, our results clearly demonstrate MDV infection in Vietnam and Taiwan for the first time and confirm that MDV can infect economically important pepper and tomato.  相似文献   
42.
Thymoma is a rare condition in horses. This case of a 24-year-old Warmblood gelding that was presented with oedema and signs of vascular congestion of the left forelimb caused by a thoracic mass is described. The diagnostic work-up included blood chemistry, cytology of pleural effusion, ultrasonography, radiography and the visualisation and collection of a tissue sample by thoracoscopy. Finally, post-mortem findings and histopathology revealed thymic epithelial neoplasia with histomorphologic features previously unreported in horses. The unique mixture of spindle-shaped and epithelioid tumour cells in combination with clear features of malignancy suggested the application of the Moran and Suster histological classification system for thymomas in humans (Moran and Suster, 2008, Curr. Treat. Options Oncol., 9, 288), which has not been reported in an equine case before and fits well to the present case.  相似文献   
43.
优质、高产转基因抗虫棉杂交种苏杂668的选育与栽培技术   总被引:1,自引:1,他引:0  
本文概述了苏杂668的选育过程,阐明了苏杂668的特征特性、产量水平、纤维品质和抗性表现,并提出其高产栽培技术措施。  相似文献   
44.
Synchytrium endobioticum is one of the most important pathogens of potato and is known for its persistent propagation structures. Under favourable conditions, infection of highly susceptible potato cultivars leads to clearly visible cauliflower‐like tissue warts, the typical symptom of potato wart disease. However, unfavourable infection conditions or low infection pressure may result in symptoms being overlooked. Thus, the introduction of pathogen structures into stages of the processing industry cannot be ruled out. As the amounts of processed potato products continue to rise, phytosanitary risks from processing discarded potatoes and potato waste in biogas plants have to be considered. Hence, the resilience of resting spores against mesophilic anaerobic digestion was analysed in stirred tank reactors. Laboratory‐scale results show that S. endobioticum not only withstands mesophilic anaerobic digestion but also subsequent storage of the digestate for at least 4 weeks. Large numbers of viable resting spores were detectable by microscopic assessment in all samples. Viability was proved and verified additionally by bioassay. Consequently, potatoes, potato waste and processing water from potato processing industries used in biogas plants pose a phytosanitary risk if the accruing digestates are returned as fertilizer to arable land.  相似文献   
45.
Plants have developed different mechanisms to absorb and solubilize phosphorus (P) in the soil, especially in environments with low P availability. This study evaluated the effects of different winter cover crops on soil P availability in a clayey subtropical (Hapludox) soil receiving soluble P fertilizer and a rock phosphate applied to the summer crop, under no‐tillage. The experiment was carried out over 3 yrs (2009–2011) with five different cover crop species: common vetch, fodder radish, ryegrass, black oat, white clover and fallow as control. The soil was sampled after the third year of cover crop cultivation and analysed for inorganic and organic P forms according to the well‐established Hedley fractionation procedure. Phosphate fertilizers promoted accumulation of both labile and nonlabile P pools in soil in the near surface layer, especially under rock phosphate. Fertilizer applications were not able to change P fractions in deeper layers, emphasizing that the Brazilian clayey soils are a sink of P from fertilizer and its mobility is almost nil. Although the cover crops recycled a great amount of P in tissue, in a short‐term evaluation (3 yrs) they only changed the content of moderately labile P in soil, indicating that long‐term studies are needed for more conclusive results.  相似文献   
46.
In the past five decades, constant research has been directed towards yield improvement in pigeonpea resulting in the deployment of several commercially acceptable cultivars in India. Though, the genesis of hybrid technology, the biggest breakthrough, enigma of stagnant productivity still remains unsolved. To sort this productivity disparity, genomic research along with conventional breeding was successfully initiated at ICRISAT. It endowed ample genomic resource providing insight in the pigeonpea genome combating production constraints in a precise and speedy manner. The availability of the draft genome sequence with a large‐scale marker resource, oriented the research towards trait mapping for flowering time, determinacy, fertility restoration, yield attributing traits and photo‐insensitivity. Defined core and mini‐core collection, still eased the pigeonpea breeding being accessible for existing genetic diversity and developing stress resistance. Modern genomic tools like next‐generation sequencing, genome‐wide selection helping in the appraisal of selection efficiency is leading towards next‐generation breeding, an awaited milestone in pigeonpea genetic enhancement. This paper emphasizes the ongoing genetic improvement in pigeonpea with an amalgam of conventional breeding as well as genomic research.  相似文献   
47.
Fish were fed a single‐strain yeast fraction (SsYF; 2 g/kg) or a multistrain yeast fraction (MsYF; 0.8 g/kg) for 10 weeks. The results demonstrated significant (p ≤ 0.03) elevations in weight gain, specific growth rate, protein efficiency ratio, and feed conversion ratio in fish fed the yeast fraction‐supplemented diets. In the distal intestine, a significant elevation in microvilli density was observed after 5 and 10 weeks of dietary supplementation with MsYF and SsYF, respectively, compared to control fed fish (p < 0.001). A significant elevation (p = 0.02) in the perimeter ratio was observed in fish fed diets supplemented with the yeast fractions. After 10 weeks of feeding on the experimental diets, Rt‐qPCR demonstrated a significant downregulation (p < 0.05) in the stress response genes, heat‐shock protein 70 (hsp70) and proliferating cell nuclear antigen (pcna), in fish fed diets supplemented with the yeast fractions. Significant (p < 0.05) elevations in interleukin 1‐beta (il1β) and interleukin‐10 (il10) gene expression were observed in fish fed diets supplemented with the MsYF compared to the other dietary groups. These findings suggest that feeding an MsYF specifically at a lower incorporation rate < 1 g/kg, compared to a commercial SsYF at 2 g/kg, is effective in improving the intestinal health status and growth performance of European seabass.  相似文献   
48.
ABSTRACT

This study deals with the influence of electron beam irradiation (EBI) on the wettability of Norway spruce surface samples. To evaluate this possible effect in detail, the changes in chemistry and wood structure were analysed using the methods of IR spectroscopy and Scanning Electron Microscopy (SEM). The surface wettability was determined by the contact angle measurement method. The results of infrared spectra show decreased relative numbers of available hydrophilic groups (e.g. hydroxyl and carbonyl groups) in the wood surfaces due to the electron beam irradiation. This behaviour is consistent with the values from the surface wettability measurements. Structural differences of the wood surfaces after electron beam irradiation were not detectable. Based on these findings pre-treatment of wood surfaces for industrial usages can be a potential field of application of this technology.  相似文献   
49.
PHD(Plant Homeodomain Finger)基因家族编码一类锌指转录因子,广泛参与植物的生长发育和逆境应答过程。通过全基因组鉴定获得了95个大豆PHD家族蛋白。通过共线性分析、进化树构建、基因结构和功能结构域鉴定、GO注释分析、不同组织间和非生物胁迫下表达分析等,获得了大豆PHD家族基因复制、家族进化、保守结构域及基因表达等信息。结果表明,大豆PHD基因在家族进化、基因结构和保守结构域上存在较大变异,可能参与Zn 2+结合、DNA结合及表观遗传调控等分子过程,参与调控植物生长发育和逆境应答。这些结果为进一步研究大豆PHD家族在生长发育和逆境应答中的生物学功能提供重要线索。  相似文献   
50.
Sepsis of the calcaneal bursae (CB) presents significant treatment challenges with limited clinical data available in the literature. The objective of this retrospective cohort study was to assess the clinical outcomes associated with CB lavage using either a through-and-through needle or bursoscopic technique. Clinical records of 29 horses treated for septic calcaneal bursitis using either technique between 2005 and 2019 were reviewed. Fisher’s exact test was used to assess statistical significance between first surgical technique and success at first surgery (i.e. not requiring >1 lavage), survival to discharge and return to work (RTW). Bursoscopy was performed in 13/29 (44.8%) cases, and needle lavage in 16/29 (55.2%). In the needle group, 12 (75%) horses were discharged following the first surgery. Four had repeat interventions; two (12.5%) had needle lavage and two (12.5%) had bursoscopy. Of the two horses to have repeat needle lavage, one was subjected to euthanasia and one discharged, and of the two that underwent bursoscopy, one was discharged and one received a third bursoscopy prior to discharge. In the bursoscopy group, seven (53.8%) were discharged and three (23.1%) were subjected to euthanasia following the first surgery. Three (23.1%) received a second bursoscopic lavage with one discharged, one subjected to euthanasia and one having a third bursoscopic lavage prior to discharge. Overall, 18/24 (75%) followed up cases RTW, 10 (55.5%) from the needle group, eight (44.4%) the bursoscopy group. No statistically significant differences between first surgical technique used and success at first surgery (no subsequent lavage(s) required), survival to discharge or return to work were detected. The main limitations of this study are that it is a retrospective study, has a small population with limited statistical power and potential selection bias. No statistically significant differences existed between the outcomes of the two techniques, contrary to the belief that bursoscopic lavage is superior. Larger, multicentred studies, with greater statistical power are required to further assess this relationship.  相似文献   
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