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11.
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
12.
Suresh Kumar Sharma Anil Kumar Srivastava 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(2):119-122
The pharmacokinetics and dosage regimen of cefotaxime following its single subcutaneous administration (10 mg/kg) were investigated in buffalo calves. Plasma and urine samples were collected over 10 and 24 h post administration, respectively. Cefotaxime in plasma and urine was estimated by microbiological assay technique using E. coli as test organism. The pharmacokinetic profiles fitted one-compartment open model. The peak plasma levels of cefotaxime were 6.48 ± 0.52 µg/ml at 30 min and the drug was detected upto 10 h. The absorption half-life and elimination half-life were 0.173 ± 0.033 h and 1.77 ± 0.02 h, respectively. The apparent volume of distribution and total body clearance were 1.17 ± 0.10 l/kg and 0.45 ± 0.03 l/kg/h, respectively. The urinary excretion of cefotaxime in 24 h, was 5.36 ± 1.19 percent of total administrated dose. A satisfactory subcutaneous dosage regimen for cefotaxime in buffalo calves would be 13 mg/kg repeated at 12 h intervals. 相似文献
13.
Parul Singh Anjil Kumar Srivastava Ashok Kumar Singh 《Pesticide biochemistry and physiology》2007,89(3):216-219
In this study, the comparison of cytogenetic effects of insecticide and fungicide in different phases of cell cycle was investigated in the root tip cells of barley (Hordeum vulgare L.). The seeds of H. vulgare L. Var. Karan 16 were treated with different concentrations (0.05%, 0.1% and 0.5%) of insecticide Profenophos (PF) and fungicide Mancozeb (MZ) for 6 h after presoaking durations of 7, 17 and 27 h.The different presoaking durations were used to bring the cells in various phases of cell cycle. Negative control was run parallel in distilled water. Cytogenetic examinations of root meristems exposed to the PF and MZ showed significant inhibition of mitotic index (MI) as well as significant increase in chromosomal aberrations (CAs). These parameters were dependent on the concentrations of insecticide and fungicide. The present study shows that PF and MZ both caused more damage in S phase of cell cycle which indicates that S phase is more sensitive in comparison to other phases. 相似文献
14.
Asheesh Shanker Aarti BhargavaRicha Bajpai Stuti SinghSucharita Srivastava Vinay Sharma 《Scientia Horticulturae》2007
Characterization of microsatellites is extremely important for the development of molecular markers. Here, we present the detection and abundance of microsatellites or simple sequence repeats (SSRs) in UniGene sequences of Citrus sinensis. A total of 427 SSRs were mined in 8786 UniGene sequences downloaded from National Center for Biotechnology Information (NCBI). Depending on the repeat units, the length of SSRs ranged from 14 to 21 for mono-, 14 to 48 for di-, 18 to 48 for tri-, 24 to 40 for tetra- and 42 bp for hexa-nucleotide repeats. Average density of SSRs (1SSR/12.92 kb of 5518.71 kb sequences mined) suggests that only 4.43% of sequences contained SSRs. Di-nucleotide repeats were most frequent repeat type (49.41%) followed by tri-nucleotide repeats (41.45%). An attempt was made to design primer pairs for 427 identified SSRs but these were found only for 216 sequences. The positions of SSRs with respect to open reading frame (ORF) detected and annotation of sequences containing SSRs were also carried out to assign function to each of the sequences. 相似文献
15.
A. R. Khan A. K. Ghorai R. C. Srivastava S. R. Singh 《Journal of Agronomy and Crop Science》1997,178(2):73-78
Intensive use of chemical herbicides and pesticides has raised serious concern about their effect on non-target organisms, plants, human bodies and the environment. Hence there is a continuous search for benign, harmless, non-hazardous and eco-friendly technology to control the growth of weeds which compete with crops for water, nutrients, light and space; thus reducing crop yield significantly. An attempt was made to control the weeds through smothering. This controls the weeds by cutting off light from the photosynthetic portion of weed plants by using black polyethylene sheets (LPDE film) which inhibit the top growth. Experiments to control the weeds in a lowland rice field through smothering were conducted in the high rainfall coastal region of eastern India wth eight treatments including smothering and conventional methods like hand/mechanical weeding and herbicides, etc. The treatment of smothering for one week + puddling + transplanting proved to be better than other conventional methods and may replace herbicide and hand/mechanical weeding totally with a better rice yield. 相似文献
16.
The isolation and NMR spectra of the triterpenoidal glycoside, 2alpha,3beta,19alpha-trihydroxyolean-12-en-28-oic acid 3-O-beta-D-galactopyranosyl- (1-->3)-beta-D-glucopyranoside (1), from the roots of Terminalia alata are reported. 相似文献
17.
Srivastava A Akoh CC Fischer J Krewer G 《Journal of agricultural and food chemistry》2007,55(8):3180-3185
In recent years, considerable attention has been paid to anthocyanins due to their abilities to inhibit oxidative stress and cell proliferation. The regulations of apoptosis and the phase II enzymes glutathione-S-transferase (GST) and quinone reductase (QR) are other potential mechanisms through which flavonoids such as anthocyanins may prevent cancer. Our study confirmed that anthocyanin fractions from high bush blueberry cultivars increased apoptosis using two different methods: DNA fragmentation and caspase-3 activity. The effect of anthocyanins on the activity of the detoxifying enzymes GST and QR was also determined. Major anthocyanins identified were delphinidin, cyanidin, peonidin, petunidin, and malvidin. In Tifblue and Powderblue cultivars, DNA fragmentation increased at anthocyanin concentrations from 50 to 150 microg/mL, but cells treated with the anthocyanin fraction of Brightblue and Brightwell showed a prominent ladder at 50-100 microg/mL when compared to cells treated with 150 microg/mL. There was a significant difference in the caspase-3 activity (P < 0.05) between the control cells and the cells treated with anthocyanins from all of the cultivars. The response correlated positively with dose. The QR activity was lower in all cells treated with an anthocyanin fraction from Tifblue, Powderblue, Brightblue, and Brightwell cultivars than in control cells (P < 0.05). The activity decreased gradually when treated with increased concentrations of anthocyanin fractions (50-150 microg/mL) in the Tifblue and Powderblue cultivars. The GST activity was lower (P < 0.05) in cells treated with anthocyanin fractions from all of the cultivars and at all concentrations. These results indicated that apoptosis was confirmed in HT-29 cells when treated with anthocyanins from blueberry cultivars at 50-150 microg/mL concentrations, but these same concentrations decrease QR and GST activities rather than induce them. 相似文献
18.
Present study is focused on the preparation of two layers composite wound dressing for drug release. The outer layer is made of hydrogel which contains of drug and the core layer is made of fabric. The two layers structure of composite dressing is formed by grafting of polyacrylamide-co-acrylic acid hydrogel on cotton fabric using ammonium per sulphate (APS) as chemical initiator and polyethylene glycol (PEG) as crosslinker. The major factors affecting graft copolymerization of hydrogel on cotton fabric are optimized by varying concentration of monomers & initiator, reaction temperature and addition time of crosslinker. Maximum grafting of hydrogel is obtained at 5 % (w/v) APS and 15 % acrylamide/acrylic acid (1:1 w/w ratio) concentration. The FTIR spectra of composite dressing shows characteristics peak of acrylic acid and acrylamide. The composite wound dressing material is loaded with model drug bovine serum albumin (BSA) and drug release behaviour is studied at different pH. The dressing shows drug release in different pH with maximum release of drug in acidic medium. 相似文献
19.
Dey S Singh VP Kumar AA Sharma B Srivastava SK Singh N 《Research in veterinary science》2007,83(1):1-4
The phylogenetic relationships of five isolates of Pasteurella multocida serotype B:2 belonging to buffalo, cattle, pig, sheep and goat were investigated by comparative sequence analysis of 16S rRNA gene. The 1468bp fragment of 16S rRNA gene sequence comparison showed that the isolates of cattle (PM75), pig (PM49) and sheep (PM82) shared 99.9% homology with the buffalo isolate (vaccine strain P52) whereas, the goat isolate (PM86) shared 99.8% homology with the vaccine strain. The 16S rRNA gene sequences of these isolates were also found monophyletic with type B reference strain NCTC 10323 of P. multocida subsp. multocida. The present study indicated the close relationships of haemorrhagic septicaemia causing P. multocida serotype B:2 isolates of buffalo and cattle with other uncommon hosts (pig, sheep and goat). 相似文献
20.