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941.
The effect of the monooxygenase inhibitor, 1-aminobenzotriazole (ABT) on isoproturon phytotoxicity and metabolism was studied in resistant (R) and susceptible (S) biotypes of Phalaris minor and in wheat (Triticum aestivum). Addition of ABT (2·5, 5 and 10 mg litre-1) to isoproturon (0·25, 0·5, 1, 2 and 4 mg litre-1) in the nutrient solution significantly enhanced the phytotoxicity of isoproturon against the R biotype. Isoproturon at 0·25 mg litre-1 reduced the dry weight (DW) of the S biotype by 77%, whereas the R biotype required 4·0 mg litre-1 for similar reduction. Addition of 10 mg litre-1 of ABT to the 0·25 mg litre-1 isoproturon caused 71 and 82% reduction in DW of R and S biotypes, respectively. Wheat was more sensitive to the mixture of isoproturon and ABT than the R biotype of P. minor. Reduced concentrations of ABT in the mixture from 10 to 2·5 mg litre-1 increased the DW of the R biotype more than that of the S biotype. The R biotype metabolised [14C]isoproturon at a faster rate than the S biotype. ABT (5 mg litre-1) inhibited the degradation of [14C]isoproturon in both biotypes of P. minor and in wheat. In the presence of ABT, about half of the applied [14C]isoproturon remained as parent herbicide in all the three species after two days. The metabolites were similar in the R and S biotypes and wheat as determined by co-chromatography with reference standards and mass spectroscopy (MS). ABT inhibited the appearance of the hydroxy and monomethyl metabolites and their conjugates in all the test plants. These results suggest that the activity of the enzymes responsible for the degradation of isoproturon is greater in the R than in the S biotype of P. minor, resulting in its rapid detoxification. Incorporation of the monooxygenase inhibitor ABT into the nutrient solution greatly inhibited the degradation of [14C]isoproturon in the R biotype and increased its phytotoxicity. Both hydroxylation and N-dealkylation reactions were found to be sensitive to ABT; inhibition of hydroxylation was greater than that of demethylation. Since ABT could not completely suppress isoproturon degradation, it is possible that more than one monooxygenase is involved. © 1998 SCI 相似文献
942.
Synergism of an oil of Azadirachta indica, a powdered extract of Allium sativum bulbs and an oleoresin of Zingiber officinale rhizomes by piperonyl butoxide and MGK-264 was studied against the snails Lymnaea acuminata and Indoplanorbis exustus. The active components of these plant-derived molluscicides, respectively azadirachtin, allicin and [6]gingerol, were also combined with these synergists. Both piperonyl butoxide and MGK-264 enhanced the toxicity of all of the test compounds. The response of snails to the synergised mixtures was both time- and dose-dependent. © 1998 Society of Chemical Industry 相似文献
943.
Grewal A. S. Singh Avtar Kumar Sanjay Kondal J. K. Kanwar J. R. Kapur J. Sawhney S. M. S. 《Tropical animal health and production》1997,29(4):104S-108S
Tropical Animal Health and Production - Bovine tropical theileriosis is of high incidence in calves below 2 months old in India. TheTheileria cell culture vaccine evolved by the Punjab Agricultural... 相似文献
944.
Paphia malabarica is an important clam species, which has formed vast beds in the Kalbadevi estuary (Shirgaon creek) and Kajali estuary (Bhatye creek), Ratnagiri. They are exploited here commercially throughout the year for local as well as external markets due to the heavy demand. This study was undertaken to assess seasonal variations in the quality of the meat of clams by estimating the condition index and percentage edibility. Higher values were recorded during the monsoon (June–August). A rapid decline was observed in the edibility values from November onwards. Higher condition index and percentage edibility were recorded from June to November, indicating the high quality of clam meat. 相似文献
945.
Rice (Oryza sativa L.) is the most important economic activity on earth as it is second largest single use of the land for food production and also consumed by the half of the world's population. Salinity is the one of the most common abiotic problem in rice growing areas of the world. Millions of hectares in the tropics, arid and semi arid region could be potential rice growing areas but either left idle or cropped with very low yielding varieties due to the lack of suitable salt tolerant high yielding modem varieties. 相似文献
946.
947.
A detailed economic analysis of a 914 tonnes/day (36,000 bu/day) “Quick Germ” ethanol process was performed. The Quick Germ ethanol process is a combination of a dry-grind and a wet-milling ethanol process. The Quick Germ ethanol process increases the coproduct value in the dry-grind ethanol process by recovering germ before fermentation. Germ is recovered using the conventional wet-milling degermination process. Economic assessment of the Quick Germ process proved profitable. The savings achieved by recovering germ as a coproduct and by increasing the fermentor capacity due to removal of nonfermentables from the corn mash will reduce the manufacturing cost of ethanol by 2.69 ¢/L (10.19 ¢/gal or $0.265/bu) when compared to the conventional dry-grind ethanol process. 相似文献
948.
949.
Rishi Tayal MVSc A. P. Singh MVSc PhD I. S. Chandna MVSc PhD S. K. Chawla MVSc 《Veterinary radiology & ultrasound》1984,25(6):260-264
Contrast cystography was performed by four different methods in 24 normal adult goats. Methods included pneumocystography, positive-contrast cystography, and double-and triple-contrast cystography. Sodium iothalamate and air were used as positive- and negative-contrast media. Amputation of urethral process in male goats was necessary for retrograde catheterization and complete evacuation of the bladder. Placement of the catheter tip beyond the neck of the bladder was not possible in male goats. Positive- and negative-contrast cystography were satisfactory for demonstration of the shape, size, and location of the bladder, while double- and triple-contrast cystography were better for visualization of bladder wall. Double-contrast cystography with pneu-moperitoneum was superior to double-contrast cystography alone for evaluation of the mucosal surface of the bladder. Complications were not encountered during or after cystography. Vesi-coureteral reflux was seen in 29% of the goats. 相似文献
950.
Detection of Salmonella dublin mammary gland infection in carrier cows, using an enzyme-linked immunosorbent assay for antibody in milk or serum 总被引:1,自引:0,他引:1
B P Smith D G Oliver P Singh G Dilling P A Martin B P Ram L S Jang N Sharkov J S Orsborn P A Marvin 《American journal of veterinary research》1989,50(8):1352-1360
An ELISA has been developed for measurement of milk and serum IgG concentrations directed against Salmonella dublin. Four groups of cows were studied: group A--7 experimentally challenge-exposed cows (infected, recovered group); group B--6 normal uninfected randomly selected control cows; group C--7 naturally occurring S dublin carrier cows; and group D--6 normal uninfected S dublin negative cows from the same herd as group C. Group-A cows were inoculated orally, or inoculated orally and then IV, but none became a S dublin carrier. As expected, all 7 group-A cows responded with a marked increase in ELISA titer after oral exposure to virulent S dublin, starting with a mean serum titer of 17.7% and reaching a peak mean serum titer of 79.3% approximately 76 days after initial exposure. As determined by necropsy and organ culturing of the remaining cows, none of the group-A cows became carriers. The mean serum ELISA titer for group-B uninfected control cows was 14.1% (SD +/- 12.8%). The mean milk ELISA titer was -1.0% (SD +/- 5.5%). Colostrum and then milk gave false-positive results for up to 2 weeks after onset of lactation. Group-B cows were culture negative for S dublin in feces and milk during lactation, and when tissues were cultured after euthanasia. Milk and serum samples for ELISA, and milk and fecal samples for culturing were taken from all group-A and -B cows twice a week for 6 months. Statistical correlation (P less than 0.05) was found between serum and milk ELISA titers.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献