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91.
M.S.Rama Mohan Rao V.Ranga Rao M Ramachandram R.C Agnihotri 《Agricultural Water Management》1977,1(4):333-342
The intake rate of the local Vertisol is very low (0.08 cm/h). Vertical mulch was used from 1971 to 1976 in order to improve infiltration. Higher moisture contents were recorded near the mulch. The favourable effects of mulch extended to 1.5 m on either side of the mulch row. Vertical mulching exerted a greater influence on crop yields under dry conditions than in normal and above normal seasons. Compared with low yields in control plots (grain: 0.2 q/ha (20 kg/ha); straw: 9.5 q/ha (950 kg/ha)) mulches spaced at 2, 4 and 8 m produced 3.9 q/ha of grain and 19.0 q/ha of straw under the extremely dry conditions of 1972–1973. However, the increase in grain and straw yields under wet conditions in 1973–1974 was only 47.2 and 15.0%, respectively. Averaged over dry and wet years, vertical mulching resulted in 45.1 and 37.9% higher grain and straw yields. The favourable effects of vertical mulching were found to last for 4 years. Considering dry and wet years, a spacing of 4 m was found to be ideal. Placing sorghum stubble as a vertical mulch to the top of the salt zone (30 cm) was found to be as good as placing it to a depth of 90 cm. 相似文献
92.
Serum samples from 163 slaughter-age ostriches (Struthio camelus) in Ohio and Indiana were tested for antibodies to avian influenza virus (AIV), Newcastle disease virus (NDV), paramyxovirus (PMV) 2, PMV3, PMV7, infectious bursal disease virus (IBDV), Bordetella avium, Mycoplasma synoviae, Mycoplasma gallisepticum, Ornithobacterium rhinotracheale, Salmonella pullorum, Salmonella gallinarum, and Salmonella typhimurium. One ostrich had antibodies to AIV H5N9, 57% of the ostriches had antibodies to NDV, four ostriches had antibodies to both NDV and PMV2, and one ostrich had antibodies to NDV, PMV2, PMV3, and PMV7. None of the ostriches had antibodies to IBDV, B. avium, M. synoviae, M. gallisepticum, O. rhinotracheale, S. pullorum, S. gallinarum, and S. typhimurium. This is the first report of antibodies to avian influenza and PMV7 in ostriches in the United States. 相似文献
93.
94.
Castro-Tirado AJ Zapatero-Osorio MR Caon N Cairos LM Hjorth J Pedersen H Andersen MI Gorosabel J Bartolini C Guarnieri A Piccioni A Frontera F Masetti N Palazzi E Pian E Greiner J Hudec R Sagar R Pandey AK Mohan V Yadav RK Nilakshi Bjornsson G Jakobsson P Burud I et al 《Science (New York, N.Y.)》1999,283(5410):2069-2073
Broad-band (ultraviolet to near-infrared) observations of the intense gamma ray burst GRB 990123 started approximately 8.5 hours after the event and continued until 18 February 1999. When combined with other data, in particular from the Robotic Telescope and Transient Source Experiment (ROTSE) and the Hubble Space Telescope (HST), evidence emerges for a smoothly declining light curve, suggesting some color dependence that could be related to a cooling break passing the ultraviolet-optical band at about 1 day after the high-energy event. The steeper decline rate seen after 1.5 to 2 days may be evidence for a collimated jet pointing toward the observer. 相似文献
95.
Improved HPLC method for the determination of curcumin,demethoxycurcumin, and bisdemethoxycurcumin 总被引:5,自引:0,他引:5
Jayaprakasha GK Jagan Mohan Rao L Sakariah KK 《Journal of agricultural and food chemistry》2002,50(13):3668-3672
Commercially available curcumin, a bright orange-yellow color pigment of turmeric, consists of a mixture of three curcuminoids, namely, curcumin, demethoxycurcumin, and bisdemethoxycurcumin. These were isolated by column chromatography and identified by spectroscopic studies. The purity of the curcuminoids was analyzed by an improved HPLC method. HPLC separation was performed on a C(18) column using three solvents, methanol, 2% AcOH, and acetonitrile, with detection at 425 nm. Four different commercially available varieties of turmeric, namely, Salem, Erode, Balasore, and local market samples, were analyzed to detect the percentage of these three curcuminoids. The percentages of curcumin, demethoxycurcumin, and bisdemethoxycurcumin as estimated using their calibration curves were found to be 1.06 +/- 0.061 to 5.65 +/- 0.040, 0.83 +/- 0.047 to 3.36 +/- 0.040, and 0.42 +/- 0.036 to 2.16 +/- 0.06, respectively, in four different samples. The total percentages of curcuminoids are 2.34 +/- 0.171 to 9.18 +/- 0.232%. 相似文献
96.
Sanjay Kumar R. Datta S. Sinha T. Kojima S. Katoh M. Mohan 《Water, air, and soil pollution》2001,130(1-4):1127-1132
Recent advances in desert afforestation underlines its viability and importance in combating global warming and acidification. In this paper, the inter-relation between afforestation, global warming and acid rain has been analyzed. Numerical simulations indicate that afforestation of deserts has distinct advantage as carbon sink and as an important factor for changing microclimate of the region rather than a source of energy. Acidic deposition may well be utilised as fertiliser in nutrient deficit soil of tropical arid areas. However, past trends and projections of acidic deposition in arid areas adjacent to Thar deserts indicate an early efforts are required to cap the opportunity. Delays may contribute towards more incidences of failures. 相似文献
97.
Summary Genetic transformation is vital to the transfer of novel genes into crop plants as well as to the emerging area of functional genomics. However, the successful genetic transformation of wheat still remains time consuming and genotype dependent. This paper updates the progress made in last 3 years towards developing a robust genetic transformation system for wheat. Agrobacterium-mediated wheat transformation offers advantages such as single-copy gene insertion, minimal rearrangement of DNA, low cost and comparatively high efficiency. The reported recent developments in wheat transformation will lead to increased efficiency of wheat breeding programs. The most promising recent progress is in the development of drought-tolerant wheat, since water stress continues to be a major limiting factor hindering world wheat productivity under adverse hot and dry weather conditions. 相似文献
98.
Rajesh J. B. Rajkhowa S. Dimri U. Prasad H. Mohan N. H. Hmar L. Sarma K. Chethan G. E. Behera P. Jaganmohanarao G. Behera S. Zosangpuii 《Tropical animal health and production》2020,52(5):2243-2250
Tropical Animal Health and Production - Porcine circovirus2 (PCV2) infection in pigs is one of the major causes of economic loss to the farmers in terms of low production, slow growth and increase... 相似文献
99.
本文是Mohan,C.V.发表于Aquaculture Asia Magazine的2009 January-March期39-42页的"National strategies for aquatic ani mal health management"一文的译文。通过对水产动物健康管理的国家战略的重要组成部分进行分析说明,作者得出如下结论:为加强对水生动物疫病的预防与控制,提高水产品在国际市场的信誉和产品竞争力,必须在全国范围内将水生动物健康管理工作进一步落实到位,逐步建立起有效的水生动物防疫监管机制,控制水生动物疫病的传播和流行,达到控制、减少、预防、以至消灭的目的,推动水产养殖业健康发展。 相似文献
100.
The occurrence of Asian grey weevil Myllocerus undatus (Curculionidae: Coleoptera) damaging coconut (Cocos nucifera L.) seedlings is reported for the first time from Kerala, India. A mild to moderate level of infestation damaging 5–10% leaf
lamina of un-split leaves with a typical notching-like symptom along the leaf margins is noticed on the majority of the coconut
seedlings belonging to different coconut varieties, viz., ‘Chowghat Orange Dwarf’, ‘Chowghat Green Dwarf’, ‘Malayan Green
Dwarf’, ‘West Coast Tall’ and Dwarf x Tall hybrids. M. undatus has not been reported as a destructive pest on any of the crops from India and is considered to be a pest of quarantine significance.
Adult weevils have a characteristic tri-spined hind femur and elytra strongly angled broader than the prothorax. 相似文献