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1.
Randomly amplified polymorphic DNA (RAPD) fingerprinting approach was applied to assess genetic diversity in different accessions of rejuvenating and intellect-promoting ancient ayurvedic medicinal herb Bacopa monnieri (L.) Pennell collected from four Southern Indian states, along with in vitro micropropagated samples maintained in the laboratory for 5 years. With the 10 analyzed primers, 110 distinct bands, in the size range of 250–870 bp were observed, and among which 14 (12.72%) were polymorphic. Among the random primers used, only OPD 02 generated highest percentage of polymorphism with 30.77. Whereas OPD 08 generated a maximum of 18 amplified bands, but with only 1% polymorphism. Cluster analysis done on the basis of similarity co-efficient generated from RAPD profiles indicated all the accessions were divided into two sub-groups based on genetic distances under one major cluster. Major cluster is only the lone loose group of the Bm.2 collected from Kerala (KER) and in vitro micropropagated plant (IVMP) maintained in the lab. The other sub-group consisted of Bm.1 and Bm.3 collected from Tamil Nadu (TN) and Andhra Pradesh (AP) respectively, which are genetically similar and showed similarity with accessions from Karnataka Bm.4 (KK). These two sub-groups were joined together at 0.66 genetic distance level. Overall, the levels of genetic similarity within the accessions varied from 0.24 to 0.80, the matrix ranged from 0.36 to 0.80, with a mean value of 0.68 indicating genetic similarity at low level.  相似文献   
2.

Purpose

Phosphorus (P) is a limiting nutrient for most US Midwestern aquatic systems and, therefore, increases of P, through point or non-point sources (NPS) of pollution such as agriculture, causes eutrophication. Identifying specific NPS contributions (e.g., upland vs. stream channels) for sediments and P is difficult due to the distributed nature of the pollution. Therefore, studies which link the spatial and temporal aspects of sediment and P transport in these systems can help better characterize the extent of NPS pollution.

Materials and methods

Our study used fingerprinting techniques to determine sources of sediments in an agricultural watershed (the North Fork of the Pheasant Branch watershed; 12.4 km2 area) in Wisconsin, USA, during the spring, summer, and fall seasons of 2009. The primary sources considered were uplands (cultivated fields), stream bank, and streambed. The model used fallout radionuclides, 137Cs, and 210Pbxs, along with total P to determine primary sediment sources. A shorter-lived fallout radioisotope, 7Be, was used to determine the sediment age and percent new sediments in streambed and suspended sediment samples (via the 7Be/210Pbxs ratio).

Results and discussion

Upland areas were the primary source of suspended sediments in the stream channels followed by stream banks. The sediment age and percent new sediment for the streambed and suspended sediments showed that the channel contained and transported newer (or more recently tagged with 7Be) sediments in the spring season (9–131 days sediment age), while relatively old sediments (165–318 days) were moving through the channel system during the fall season.

Conclusions

Upland areas are the major contributors to in-stream suspended sediments in this watershed. Sediment resuspension in stream channels could play an important role during the later part of the year. Best management practices should be targeted in the upland areas to reduce the export of sediments and sediment-bound P from agricultural watersheds.  相似文献   
3.
BACKGROUND: The study reported here was undertaken to assess the presence of antibodies to Sarcocystis neurona in the serum of horses of North American origin that had been relocated for 1 year or more to India (ie, outside of the known endemic areas for S. neurona). HYPOTHESIS: The presence or absence of such antibodies should provide information concerning the persistence of such antibodies, or support the presence of chronic infection, or both. ANIMALS: A total of 228 Thoroughbred horses were sampled in India, of which 86 were of North American origin that had been in India between 1 and 13 years, 124 were Indian-born horses that had never been out of India, 8 were of Irish origin, 8 were of English origin, and 2 were originally from France. METHODS: Sera were tested using established western blot analysis. RESULTS: Of the Indian-born horses, 0.8% were test positive, and of the North American horses, 42% were test positive. All of the English and Irish horses were test negative, and the 2 French horses were test positive. CONCLUSIONS AND CLINICAL IMPORTANCE: These data indicate that antibodies against S. neurona can be detected for many years after horses have been removed from an endemic area and that this may be attributable to long half-life of the antibodies or to chronic infection and ongoing antibody production, or both.  相似文献   
4.

Shrimp farming industries are subjected to severe economic loss due to a disease called white spot syndrome, a viral disease caused by white spot syndrome virus (WSSV) in penaeid shrimp. Numerous active compounds in the market possess anti-viral activity against the white spot syndrome virus, yet the issue remains unsolved. The present study was carried out to determine the anti-viral activity of methyl 1-chloro-7-methyl-2-propyl-1h-benzo[d] imidazole-5-carboxylate (C13H15N2O2Cl) against WSSV. The anti-viral activity of the synthetic compound was determined in freshwater crabs. Crabs were divided into three different experimental groups: healthy control groups (N.C.) received NTE buffer, positive control group (P.C.) crabs received WSSV, and treatment group crabs received WSSV along with synthetic weight compound. Experimental groups were observed for 30 days post-infection. Three different organs (gills, muscles, and head soft tissue (HST)) were dissected from all three groups and analyzed using molecular-based techniques, including polymerase chain reaction (PCR), Western blot, and histopathology. Clinical signs of WSSV were observed in the positive and N.C. groups; however, the treatment group showed a 100% survival rate. Confirmation was done using PCR, Western blot, and histopathology. These results demonstrated that the given synthetic compound has significant anti-viral activity against WSSV.

  相似文献   
5.
In this study, we examined the necrosis phenotype on leaves of two cultivars of soybean (ZheA8901 and Nannong1138-2) that show varying level of resistance to soybean mosaic virus (SMV). The necrotic symptoms seen on inoculated and systemic leaves of soybean cultivar ZheA8901 were reminiscent of programmed cell death (PCD). The cell death phenotypes were evaluated using the TUNEL method, quantification of hydrogen peroxide (H2O2) and salicylic acid, callose production, as well as by monitoring expression of defence genes GmPR-1 and GmNPR1. Our results show that SMV inoculation induced PCD on ZheA8901 is associated with rapid increase in H2O2, increased SA and callose accumulation and higher defence gene expression.  相似文献   
6.
The present study aimed to assess the potentiality of water soluble fungal pigments for dyeing on cotton yarn. Five different shades of pigments were extracted from Monascus purpureus, Isaria farinosa, Emericella nidulans, Fusarium verticillioides, and Penicillium purpurogenum using ethanol. Maximum concentration of pigment was obtained from Monascus purpureus (red, 25.02±1.6 UA) followed by Penicillium purpurogenum (yellow, 23.05±0.3 UA). The optimum dyeing condition was observed at a pigment concentration of 1 gram, pH 5, temperature 80 °C, time duration 90 min, and a liquor ratio of 1:30 was found to be the optimal for dyeing. Maximum uptake of 80 % was achieved with Monascus purpureus red pigment. Moreover, the effect of mordant in dyeing was evaluated by different mordanting methods. A strong variation in shade and color depth could be achieved by using pre-mordanting method with alum and ferrous sulfate giving better wash fastness properties when compared with post-mordanting or without a mordant.  相似文献   
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8.
The intensity of rice false smut disease in selected states of northwest and south India was studied. In northern Indian states as a whole, disease incidence (percentage of false smut-infected tillers) varied from 2% to 75%. In the state of Haryana, maximum infection was recorded on hybrids like PA 6444 and PA 6129 while in Punjab state, 10–20% disease incidence was recorded in popular inbred rice varieties like PR 114, PA 116 and PAU 201. In the southern state of Tamil Nadu, the disease incidence varied from 5% to 85%. A heavy incidence of the disease was noticed in variety BPT 5204 and due to this, the air above the infected field gave a black smoky appearance from a distance as a result of release of spore mass in the atmosphere. In severe cases the number of infected grains reached even more than 100 per panicle. The pathogen Ustilaginoidea virens was isolated in potato dextrose agar medium and was characterized by both pathogenicity test and molecular analysis. Under glasshouse conditions, when a conidial suspension of the pathogen was injected during boot leaf stage of the rice variety TN1, typical smut balls were observed. The identity of the pathogen was further confirmed through polymerase chain reaction (PCR) analysis using U. virens-specific internal transcribed spacer (ITS) primers. The primer pair US 1-5/US3-3 and US2-5/US4-3 amplified 380 bp and 232 bp product, respectively, which are typical for the U. virens fungus.  相似文献   
9.
Sugar beet (Beta vulgaris L. subsp. vulgaris var. altissima) is a biennial, sugar-producing tuber crop grown in different parts of the world. Diseased sugar beets with symptoms of little leaf were observed during 2008 in Tamil Nadu, India. Phytoplasmas were detected in symptomatic leaves of three separate plants using PCR with primer pair fU5/rU3, which amplify an 880-bp fragment of the 16S rRNA region of phytoplasmas. The nucleotide sequence analysis of a 766-bp fragment had 100% identity among the sequence from the three plants (GQ184437) and 96% nucleotide sequence identity with 16S ribosomal RNA gene sequences of eggplant phyllody phytoplasma.  相似文献   
10.
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