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1.
Tomato is the most economically important fruit/vegetable crop grown worldwide. However, viral diseases remain an important factor limiting its productivity, with estimated quantitative and qualitative yield losses in tomato crops often reaching up to 100%. Many viruses infecting tomato have been reported, while new viral diseases have also emerged. The climatic changes the world is experiencing can be a contributing factor to the successful spread of newly emerging viruses, as well as the establishment of disease in areas that were previously either unfavourable or where the disease was absent. Because antiviral products are not available, strategies to mitigate viral diseases rely on genetic resistance/tolerance to infection, control of vectors, improvement in crop hygiene, roguing of infected plants and seed certification. Tomato brown rugose fruit virus (ToBRFV) is an emerging viral threat to tomato productivity and is currently spreading into new areas, which is of great concern to the growing global production in the absence of mitigation measures. This review presents the current knowledge about ToBRFV and future prospects for an improved understanding of the virus, which will be needed to support effective control and mitigation of the impact it is likely to cause. 相似文献
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de Melo Rafaela Leitão Correia Dutra Júnior Wilson Moreira Palhares Liliane Olímpio de Moura Ferreira Débora Nathália de Aquino Rafael Santos Cordeiro Manso Helena Emília Cavalcanti 《Tropical animal health and production》2019,51(5):1057-1063
Tropical Animal Health and Production - The objective of this study was to evaluate the biochemical, behavioral, and physiological parameters in pregnant sows of native and improved crossbreeds... 相似文献
4.
本研究以饲料玉米(Zea mays)为原料,采用绿叶汁发酵液1.0%、1.5%、2.0%作青贮添加剂,并与传统青贮工艺添加1%、3% NaCl做比较,在实验室条件下贮藏60 d。测定其青贮品质(包括微生物群落结构、pH值、粗蛋白、干物质、纤维素含量、有机酸含量)及体外消化率,并与传统青贮工艺做比较。结果显示,添加绿叶汁发酵液可以明显改善青贮品质,pH值显著降低,干物质、粗蛋白及有机酸含量均有显著性增加(P<0.05)。经体外消化试验可知,与对照相比,添加绿叶汁发酵液可显著提高青贮饲料消化率。 相似文献
5.
Lasmar Chaim J. Queiroz Antônio C. M. Rosa Clarissa Carvalho Nathália S. Schmidt Fernando A. Solar Ricardo R. C. Paolucci Lucas N. Cuissi Rafael G. Ribas Carla R. 《Landscape Ecology》2021,36(9):2583-2597
Landscape Ecology - Harmful effects of habitat loss and fragmentation can be detected across multiple spatial scales, yet most studies that aim to characterize these effects take place at a single... 相似文献
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Ether and methanol extracts of Ixora coccinea dry leaves were tested for their antimicrobial activity. Ether fraction was found to be more active than the methanol fraction. 相似文献
7.
Antimicrobial activity of Memecylon malabaricum leaves 总被引:4,自引:0,他引:4
The petroleum ether, chloroform and methanol extracts of Memecylon malabaricum leaves were tested for antimicrobial activity. Only methanol extract has shown activity against bacteria both Gram (+) and Gram (-), and fungi. 相似文献
8.
A. K. Sarkar Ekta Rai Syed Naseer Shah Sulochna Bouddha Y. K. Bansal S. A. Ansari 《New Forests》2010,40(3):323-334
Changes in nitrate reductase, i.e. NR (E.C. 1.7.1.1) activity, peroxidase (E.C. 1.11.1.14) activity, soluble sugars and phenols were monitored at various time intervals from day 0 to 60 during in vitro adventitious shoot regeneration from leaflet explants of Albizia procera (Roxb.) Benth. The explants were incubated on semi-solid Murashige and Skoog medium supplemented with 2.6 g l?1 Phytagel®, 2.5% sucrose, 10 μM BAP, 1 μM NAA and 15 μM AgNO3. NR activity, soluble sugars and phenols exhibited initial sharp rise on around day 20 followed by steep decline on day 25, whereas peroxidase activity peaked on day 50, highlighting significance of early input of nitrogen and energy and late emergence of lignification process for cellular differentiation and organization into adventitious shoot primordia. Morpho-anatomical changes in leaflets at various stages of in vitro adventitious shoot formation also followed the endogenous biochemical pattern. 相似文献
9.
Atiqur Rahman Barbhuiya Ayyanadar Arunachalam Prabhat Chandra Nath Mohammed Latif Khan Kusum Arunachalam 《Journal of Forest Research》2008,13(1):25-34
Rates of weight loss and nutrient (N and P) release patterns were studied in the leaf litter of the dominant tree species
(Ailanthus grandis, Altingia excelsa, Castanopsis indica, Duabanga sonneriatioides, Dysoxylum binectariferum, Mesua ferrea,
Shorea assamica, Taluma hodgsonii, Terminalia myriocarpa and Vatica lancefolia) of a tropical wet evergreen forest of northeast India. Nitrogen and phosphorus mineralization rate and decay pattern varied
significantly from species to species. In general, the decay pattern, characterized by using a composite polynomial regression
equation, exhibited three distinct phases of decay during litter decomposition—an initial slow decay phase (0.063% weight
loss day−1), followed by a rapid decay phase (0.494% weight loss day−1) and a final slow decay phase (0.136% weight loss day−1). The initial chemical composition of the litter affected decomposition rates and patterns. Species like D. sonneriatoides, D. binectariferum, and T. hodgsonii with higher N and P content, lower carbon and lignin content, and lower C:N ratio and lignin:N ratio exhibited relatively
faster decomposition rates than the other species, for example M. ferrea, C. indica and A. grandis. A slow decay rate was recorded for species such as M. ferrea, C. indica, and A. grandis. The initial N and P content of litter showed significant positive correlations with decay rates. Carbon and lignin content,
lignin:N, and C:N showed significant negative correlations with decay rates. Soil total N and P, and rainfall, soil temperature,
and soil moisture had positive correlations with decay rates. The rapid decomposition rates observed in comparison with other
different forest litter decay rates confirm that tropical wet evergreen forest species are characterized by faster decomposition
rates, indicating a faster rate of organic matter turnover and rapid nutrient cycling. 相似文献
10.
Soil moisture affects various hydrological processes, including evapotranspiration, infiltration, and runoff. Forested areas in the lower western Himalaya in India constitute the headwater catchments for many hill streams and have experienced degradation in forest cover due to grazing, deforestation and other human activities. This change in forest cover is likely to alter the soil moisture regime and, consequently, flow regimes in streams. The effect of change in forest cover on soil moisture regimes of this dry region has not been studied through long term field observations. We monitored soil matric potentials in two small watersheds in the lower western Himalaya of India. The watersheds consisted of homogeneous land covers of moderately dense oak forest and moderately degraded mixed oak forest. Observations were recorded at three sites at three depths in each watershed at fortnightly intervals for a period of three years. The soil moisture contents derived from soil potential measurements were analyzed to understand the spatial, temporal and profile variations under the two structures of forest cover. The analysis revealed large variations in soil moisture storage at different sites and depths and also during different seasons in each watershed. Mean soil moisture storage during monsoon, winter and summer seasons was higher under dense forest than under degraded forest. Highest soil moisture content occurred at shallow soil profiles, decreasing with depth in both watersheds. A high positive correlation was found between tree density and soil moisture content. Mean soil moisture content over the entire study period was higher under dense forest than under degraded forest. This indicated a potential for soil water storage under well managed oak forest. Because soil water storage is vital for sustenance of low flows, attention is needed on the management of oak forests in the Himalayan region. 相似文献