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41.
K. M. Makkouk S. G. Kumari L. Bos 《European journal of plant pathology / European Foundation for Plant Pathology》1990,96(5):291-300
A virus affecting faba bean in West Asia and Norht Africa was identified as broad bean wilt virus (BBWV) by host reactions, particle morphology and size, serology and transmission characteristics. An isolate from Syria (SV3-88) and one from Egypt (EV319-86) were found to be serologically identical and of serotype I. In host-range studies, the Syrian isolate infected systemically 59 out of 87 plant species tested. The virus was transmitted non-persistently by four aphid species naturally prevalent in Syria, but most efficiently byMyzus persicae. Inoculation of faba bean with SV3-88 14 weeks (pre-flowering) and 6 weeks after sowing (flowering) led to 25.8 and 1.8% yield loss and seed-transmission rates of 0.6 and 0.4%, respectively. The isolate SV3-88 was purified from systemically infected faba bean and yield 1.5–2 mg of partially purified virus per 100 g of leaves. When samples, with symptoms suggestive of virus infection, were collected during 1985–1989 from a number of countries in West Asia and North Africa and tested by ELISA, the virus was detected in 8 out of 127 samples tested (8/127) from Egypt, 0/44 from Lebanon, 1/23 from Morocco, 38/485 from the Sudan, 38/385 from Syria and 23/138 from Tunisia.Samenvatting Een virus uit veldboon of faba boon (Vicia faba) in West Azië en Noord-Afrika werd als tuinboneverwelkingsvirus (Fabavirus-groep) herkend aan zijn waardplantreacties, deeltjesvorm en grootte, serologie en wijze van overdracht. Een isolaat uit Syrië (SV3-88) en één uit Egypte (EV319-86) bleken serologisch identiek te zijn en te behoren tot serotype I van het virus. Met het Syrische isolaat kon in 59 van de 87 getoetste plantesoorten systemische infectie worden verkregen. Met vier veel in Syrië voorkomende bladluissorten kon het virus worden overgebracht, maar metMyzus persicae naar de meeste plantesoorten. Inoculatie van veldboon met SV3-88 vóór de bloei (14 weken na het zaaien) en tijdens de bloei (16 weken na het zaaien) gaf aanleiding tot respectivelijk 25,8 en 1,8% opbrengstreductie en tot 0,6 en 0,4% zaadoverdracht. Bij zuivering van isolaat SV3-88 uit systemisch geïnfecteerde fababoon was de opbrengst tot 1,5 à 2 mg gedeeltelijk gezuiverd virus per 100 g blad. Bij ELISA-toetsing in 1985–1989 van een groot aantal monsters afkomstig uit een aantal landen in West-Azië en Noord-Afrika werd het virus aangetoond in 8 van de 127 (8/127) monsters uit Egypte, 0/44 uit Libanon, 1/23 uit Marokko, 38/485 uit Soedan, 38/385 uit Syrië en 23/138 uit Tunesië. 相似文献
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Nisha Sharma Raman Narang Neeraj Kashyap Soni Kumari Simarjeet Kaur Poonam Ratwan 《Tropical animal health and production》2018,50(6):1219-1225
The present study was undertaken to estimate effect of various genetic and non-genetic factors on persistency of milk production and to identify the most appropriate persistency method that fits best in our environment. In the present study, effects of different non-genetic factors, viz. year, season, days to attain peak yield, and genetic group based on the level of exotic inheritance on persistency of milk yield in crossbred cattle were studied. Data comprised of 686 first lactation daily milk yield records of crossbred cattle that were maintained at GADVASU dairy farm over a period of 25 years from 1991 to 2015 were utilized to calculate persistency coefficients by four methods, viz., Ludwick and Peterson method (P1), Mahadevan method (P2), ratio method (P3), and Prasad et al. method (P4). Overall least squares means for persistency by Ludwick and Peterson method (P1), Mahadevan method (P2), ratio method (P3), and Prasad et al. method (P4) were 0.896?±?0.096, 1.385?±?0.224, 187.207?±?26.398, and 0.621?±?0.098, respectively. Effect of sires was significant (P?<?0.05) on P2 and P4 methods. Effect of genetic group on all four methods was non-significant. Period of calving had significant (P?<?0.01) effect on persistency of milk yield (P2, P3, and P4 methods). Effect of season of calving on persistency of milk yield was found to be significant in all estimates obtained by the four methods. Summer and autumn calvers were most persistent whereas spring and winter calvers were least persistent for (P2, P3, and P4 methods). Persistency of milk yield was significantly (P?<?0.05) affected by days to attain peak yield in P1 and P2 methods. Maximum persistency was obtained in animals attaining peak at 41–57 days of lactation and minimum in <?41 days for Mahadevan method and ratio method. The highest heritability of persistency and minimum value of standard error was estimated as 0.275?±?0.11 for the Mahadevan method followed by the Prasad method (0.197?±?0.10) by half sib correlation method. The maximum coefficient of variation which indicates available variability was estimated as 20.788% for persistency by the Mahadevan method followed by 18.969% for the Prasad method. The highest correlation was also observed between P1 and P3 methods by Spearman’s and Pearson’s correlation for least squares breeding value of the sires. On the basis of heritability, standard error of heritability, and coefficient of variation, it can be concluded that the Mahadevan method followed by the Prasad method suits best to our environment for animals in first lactation as well as they can be utilized for effective selection for higher persistency in crossbred animals of Punjab. 相似文献
44.
Lokugamage N Kariwa H Lokugamage K Hagiya T Miyamoto H Iwasa MA Araki K Yoshimatsu K Arikawa J Mizutani T Takashima I 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(11):1189-1194
Puumala (PUU) virus and PUU-related viruses are difficult to isolate in cell culture. To determine whether animal inoculation would be a better alternative for virus recovery, the Sotkamo strain of PUU virus was inoculated into several animal species. Newborn Mongolian gerbils (MGs), mice, and rats were infected with the Sotkamo strain by intracerebral (ic), intraperitoneal (ip), and subcutaneous (sc) inoculation. Antibodies to PUU appeared in MGs at 30 days post-infection (dpi), and in mice and rats at 15 dpi. Interestingly, virus appeared at 7 dpi in lung and brain of MGs inoculated via ic and ip routes. Virus was detected in all tested tissues of MGs at 15 dpi, with a peak level of 1.36 x 10 (5) focus forming units (FFU)/g in brain tissue. The virus titer declined with the onset of the antibody response and became undetectable by 75 dpi, when the antibody titer reached the maximum level. The appearance of the virus in mice and rats was delayed as compared to MGs, and the virus titer was apparently lower, at approximately 4 to 8 x 10(3) FFU/g, at 15 dpi. In addition, lung homogenates of antibody-positive Clethrionomys (C.) rufocanus (captured in Tobetsu, Hokkaido, Japan) were inoculated into MGs by the ic route. PUU-related viral RNA was detected at 16 dpi in the brains of MG inoculated with the lung homogenate, and antibodies were detected at 45 dpi. These findings indicate that newborn MG inoculation is an efficient method to recover PUU and PUU-related viruses. 相似文献
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Sarada R Vidhyavathi R Usha D Ravishankar GA 《Journal of agricultural and food chemistry》2006,54(20):7585-7588
Haematococcus pluvialis is one of the potent organisms for production of astaxanthin, a high value ketocarotenoid. Astaxanthin is accumulated in thick-walled cyst cells of Haematococcus. The thick cell wall is made up of sporopollenin-like material, algaenan, which hinders solvent extraction of astaxanthin. In the present study, an improved method for extraction of astaxanthin without homogenization of cells is reported. Extractability of astaxanthin from cyst cells was evaluated by treating cells with various solvents and pretreating the cells with organic and mineral acids at 70 degrees C followed by acetone extraction. Hydrochloric acid treatment facilitated 86-94% extractability of astaxanthin. Treatment time, temperature, and concentration of the acid were found to be critical factors for maximum extractability. The treatment did not affect the astaxanthin ester profile and the treated cells can be preserved until further use. 相似文献
47.
Two varieties of finger millet (Eleusine coracana)-a tannin-containing red variety, CO13, and nontannin white variety, CO9-processed by treatment with enzymes (cellulase and hemicellulase) and fermentation with starters (from previously fermented finger millet batter), achieved the desirable goals of reduced fermentation time (12 h), increased acidity (2.2 to 2.4%), enhanced in vitro protein digestibility (IVPD) (14 to 26%), and mineral availability compared to 48 h uncontrolled natural fermentation (Usha Antony and Chandra, 1998). Fermentation with starters alone increased titratable acidity (1.02 to 1.88%), IVPD (5. 5 to 22%) and mineral availability, and decreased phytate (23 to 26%) and tannin (10.8 to 40.5%) in the millets. Enzymatic treatment (3 h, 50 degrees C) did not significantly alter the pH, phytate, tannins, IVPD, or HCl-mineral extractability but enhanced fermentative changes. Overall, the changes were marked when the 48 h starter was used and the improvements in nutrient availability was greater in the CO13 variety. 相似文献
48.
生防制剂与呋喃丹颗粒剂防治根结线虫幼虫的效果 总被引:2,自引:0,他引:2
印度南方根结线虫广泛地分布于印度南部灌桑园,特别是轻质土壤的桑园,它严重地影响桑叶的产量和质量,人们曾采用农业和化学等防治措施进行桑园线虫的防治,但效果并不理想,为此,考虑用生物防治方法来进行试验研究,本研究采用拟青霉和轮枝孢真菌两种生防制剂及化学杀线虫剂呋喃丹颗粒剂对线虫幼虫进行致死性试验。每种生物制剂滤液设置3个浓度,分别为100%,75%,和50%,结果发现,该两种真菌制剂在滤液浓100%下72h后的杀虫率分别为73.55%和78.45%,两者无显著差异。虽然它们对幼虫的致死效果比化学杀线虫剂呋喃丹效果略微差些,但生物剂对自然环境,人畜安全,因此,生物制肯望成为更经济,更安全的杀线虫剂。 相似文献
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Acharya U Patel S Koundakjian E Nagashima K Han X Acharya JK 《Science (New York, N.Y.)》2003,299(5613):1740-1743
Mutations in proteins of the Drosophila phototransduction cascade, a prototypic guanine nucleotide-binding protein-coupled receptor signaling system, lead to retinal degeneration and have been used as models to understand human degenerative disorders. Here, modulating the sphingolipid biosynthetic pathway rescued retinal degeneration in Drosophila mutants. Targeted expression of Drosophila neutral ceramidase rescued retinal degeneration in arrestin and phospholipase C mutants. Decreasing flux through the de novo sphingolipid biosynthetic pathway also suppressed degeneration in these mutants. Both genetic backgrounds modulated the endocytic machinery because they suppressed defects in a dynamin mutant. Suppression of degeneration in arrestin mutant flies expressing ceramidase correlated with a decrease in ceramide levels. Thus, enzymes of sphingolipid metabolism may be suitable targets in the therapeutic management of retinal degeneration. 相似文献