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11.
Pratap Chandra Das Joykrushna Jena Bibhudatta Mishra Bikash Kumar Pati 《Journal of the World Aquaculture Society》2012,43(1):128-134
Impact of aeration on growth of silver barb, Puntius gonionotus during fingerling rearing was studied through a 100‐d rearing experiment conducted in 18 concrete tanks of 50 m2 (10 × 5 × 1.2 m) size. Fry (0.74 ± 0.27 g, 35 ± 6 mm) were stocked in the experimental tanks at three stocking densities (25, 50, and 75 fry/m2) and were evaluated with and without provision of 6 h (2400–0600 h) of night time aeration. Aeration resulted in higher pH and dissolved oxygen regime and increased fingerling length and weight. The results suggest a rearing density of 75/m2 to be ideal for rearing fry to fingerling of this species when aeration is provided, whereas, under non‐aerated condition, rearing the fry to fingerling stage at 50/m2 was found advantageous over those at 25 and 75/m2. 相似文献
12.
R. Ramesh Kumar L. Prasanna Anjaneya ReddyJ. Vinay Kumar K. KomaraiahS. Purnanand K.P. Sastry 《Industrial Crops and Products》2012,35(1):199-202
Ashwagandha (Withania somnifera) is an important medicinal plant and its dried roots are used in traditional systems of medicine. The market price of roots is determined by physical (textural) quality. Brittle roots with high starch and low fiber are considered to be superior because of ease in grinding. Genetic diversity studies based on root textural parameters have not been done so far. So the present study was designed to assess genetic diversity for morphometric traits and root textural quality parameters among two morphologically distinct groups: Poshita and Nagore. The PCA separated the morphometric and root texture variables distinctly into two different principal components: PC-1 and PC-2 respectively, indicating that both are negatively associated. All the morphotypes in Poshita group showed high positive loadings in PC-1 indicating that component genotypes are high root yielding. Nagore morphotypes were low yielding but the root texture was good. Clustering of morphotypes grouped Poshita and Nagore separately with high inter-cluster distances indicating that both groups are highly divergent from each other, suggesting that there is sufficient scope for varietal improvement through hybridization. 相似文献
13.
Rao GS Ramesh S Ahmad AH Tripathi HC Sharma LD Malik JK 《Veterinary research communications》2001,25(3):197-204
The pharmacokinetics of enrofloxacin and its active metabolite ciprofloxacin were investigated in goats after a single intramuscular administration of enrofloxacin at 2.5 mg/kg body weight. The plasma concentrations of enrofloxacin and ciprofloxacin were determined simultaneously by a HPLC method. The peak concentrations (C
max) of enrofloxacin (1.13 g/ml) and ciprofloxacin (0.24 g/ml) were observed at 0.8 and 1.2 h, respectively. The elimination half-life (t
1/2), volume of distribution (V
d(area)), total body clearance (ClB) and mean residence time (MRT) of enrofloxacin were 0.74 h, 1.42 L/kg, 1329 ml/h per kg and 1.54 h, respectively. The t
1/2, area under the plasma concentration–time curve (AUC) and the MRT of ciprofloxacin were 1.38 h, 0.74 g h/ml and 2.73 h, respectively. The metabolic conversion of enrofloxacin to ciprofloxacin was appreciable (36%) and the sum of the plasma concentrations of enrofloxacin and ciprofloxacin was maintained at or above 0.1 g/ml for up to 4 h. Enrofloxacin appears to be useful for the treatment of goat diseases associated with pathogens sensitive to this drug. 相似文献
14.
A leaf curl and mottle disease was observed naturally affecting plants of Trigonella corniculata. A geminivirus was detected in infected plants by PCR using degenerate geminivirus primers and by Southern hybridization with a probe specific to tomato leaf curl begomovirus. This is the first report of a member of the Geminiviridae naturally occurring in T. corniculata. 相似文献
15.
Weeds PL Chakraborty S Fernandes CD d'A Charchar MJ Ramesh CR Kexian Y Kelemu S 《Phytopathology》2003,93(2):176-185
ABSTRACT Using molecular markers, this work compares the genetic diversity in Colletotrichum gloeosporioides infecting species of the tropical forage legume Stylosanthes at the center of origin in Brazil and Colombia with that of Australia, China, and India, where Stylosanthes spp. have been introduced for commercial use. There was extensive diversity in the pathogen population from Brazil, Colombia, China, and India. The Australian pathogen population was least diverse probably due to its geographical isolation and effective quarantine. The extensive diversity in China and India means that threats from exotic pathogen races to Stylosanthes pastures can potentially come from countries outside the South American center of origin. In Brazil and India, both with native Stylosanthes populations, a high level of genetic differentiation in the pathogen population was associated with sites where native or naturalized host population was widely distributed. There was limited genetic diversity at germplasm evaluation sites, with a large proportion of isolates having identical haplotypes. This contrasts recent pathogenicity results for 78 of the Brazilian isolates that show hot spots of complex races are more common around research stations where host germplasm are tested, but few are found at sites containing wild host populations. For a pathogen in which the same races arise convergently from different genetic backgrounds, this study highlights the importance of using both virulence and selectively neutral markers to understand pathogen population structure. 相似文献
16.
Pasnik DJ Vemulapalli R Smith SA Schurig GG 《Veterinary immunology and immunopathology》2003,95(1-2):43-52
A recombinant vaccine was constructed for piscine mycobacteriosis utilizing a Brucella abortus strain RB51 vector expressing a mammalian Mycobacterium sp. 85A antigen. Juvenile striped bass were inoculated with the resulting construct at doses equivalent to 10(6), 10(7), 10(8), 10(9), and 10(10) colony-forming units/fish. Blood and tissue samples from these fish demonstrated significant specific humoral and cell-mediated immune responses towards the 85A antigen in a dose-dependent manner. However, survival studies determined that inoculated fish failed to demonstrate cross-protective responses after live Mycobacterium marinum challenge 70 days post-inoculation. 相似文献
17.
A detailed study has been conducted to evaluate the residues of endosulfan and its principal metabolite (alpha-endosulfan, beta-endosulfan and endosulfan sulfate) which may have accumulated in environmental samples due to regular aerial spray application of endosulfan on cashew leaf plantation for a period of 20 years. Three months after the last spray of endosulfan 350 g litre-1 EC at 300 ml acre-1 (equivalent to 105 g AI acre-1 = 42.5 g ha-1), a total of 93 samples of cow milk, fish, water, soil and dried cashew leaf were collected from a village in Kasargode District, Kerala, India, where endosulfan contamination was likely to have occurred. All the samples were analyzed for total residues of endosulfan (comprising alpha- and beta-endosulfan), endosulfan sulfate and also the potential hydrolysis product endosulfan diol, using gas chromatography with electron capture detection. The minimum detection limits of total endosulfan was 0.001 microgram g-1. Analysis of soil samples showed the deposition of total endosulfan residues in the range < 0.001-0.010 microgram g-1, and dried leaf samples showed residues of endosulfan in the range < 0.001-3.43 micrograms g-1 dry weight. In cow milk, fish and water, endosulfan residues could not be detected above the minimum detection limit. Endosulfan diol was not observed in any sample. The data obtained was confirmed by GC-MS-EI using selective ion monitoring (SIM) mode. 相似文献
18.
Chanda Kushwaha Ramesh Chand Chandra Prakash Srivastava 《European journal of plant pathology / European Foundation for Plant Pathology》2006,115(3):323-330
Aeciospores in Uromyces fabae were found to be repeating spores and play an important role in pea rust outbreaks in the North Eastern Plain Zone (NEPZ) of India. Experiments conducted on pea rust from 2001 to 2004 revealed the dominance of aeciospores at all growth stages of pea in this region. Urediospore production was erratic and was only observed in a few samples of stems and tendrils (5–10%). Inoculation of pea plants either by aeciospores or urediospores resulted in the production of aeciospores. Production of aeciospores was observed at a temperature range of 10–25 °C, with a maximum at 25 ± 2 °C. Among the different growth stages of pea, the pod formation stage was highly susceptible and produced the maximum number (744) of aecidia/leaf at 20–25 °C. Significant effects of growth stages and temperature were also noticed for pustule number. Urediospore production mainly coincided with the senescence of the pea plants. Maximum germination (2%) of aeciospores was observed at 25 °C, whereas maximum urediospore germination (3.5%) was at 15 °C. Temperatures > 15 °C decreased urediospore germination. A relative humidity (RH) of 100% was favourable for aeciospore germination while 98% RH favoured urediospore germination. Typical histo-pathological behaviour of the aeciospores was observed. 相似文献
19.
R. Chandra Babu V. Muralidharan M. Seetha Rani M. Nagarajan S. R. Sree Rangasamy R. K. Pallikonda Perumal 《Journal of Agronomy and Crop Science》1990,164(3):213-216
The effect of seed size on germination and seedling growth was assessed using cultivars of greengram and blackgram. Significant positive correlation was noticed between seed size and germination, seedling height, root length, primary leaf size and seedling weight. The possible advantages of choosing cultivars with heavier seeds for attaining better crop stand especially under rainfed situation are discussed. 相似文献
20.
K. Premkumar A. Pachiappan Suresh K. Abraham S. T. Santhiya P. M. Gopinath A. Ramesh 《Fitoterapia》2001,72(8):398-911
Spirulina fusiformis was tested for its possible in vivo protective effects against cyclophosphamide (CP) and mitomycin-C (MMC) induced genotoxicity and oxidative stress in mice. Pre-treatment with S. fusiformis (250, 500 and 1000 mg kg(-1), p.o., daily for 5 days) significantly reduced the chromosomal damage and lipid peroxidation with concomitant changes in antioxidants and detoxification systems. All the three tested doses were effective in exerting a protective effect against CP and MMC. 相似文献