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91.
Kallamadi Prathap Reddy Sankaraneni Chander Rao Pulugurtha Bharadwaja Kirti Mulpuri Sujatha 《Euphytica》2013,190(3):385-399
Powdery mildew incited by Golovinomyces cichoracearum has become a serious problem on sunflower in India during the past 2–3 years. Genetic resistance in the released cultivars and the parental lines of hybrids is rather limited. Hence, screening of about 420 accessions comprising of wild Helianthus species, interspecific derivatives, core germplasm, inbred lines and few exotic accessions was done under natural field conditions for 2 years and further confirmed by screening under artificial inoculation conditions. PCR analysis using primers specific to powdery mildew causing genera gave a 391 bp band which confirmed the pathogen as G. cichoracearum. Seven different screening methods were tested which induced infection, but dusting of spores on to the healthy leaves proved to be convenient and more effective method of infection. Based on the differential response of the accessions derived from diverse genetic backgrounds, a scale for obtaining reliable estimates of the disease has been devised. Among different cultivar germplasm accessions, the disease severity index (DSI) ranged from 15 to 100 and area under disease progression curve (AUDPC) ranged from 95 to 648. Among the four groups of cultivated sunflower accessions tested, DSI and AUDPC was in the order of exotic lines < interspecific derivatives < inbred lines < core germplasm. Reliable sources of resistance to the pathogen were identified in four annual wild species (H. argophyllus, H. agrestis, H. debilis, H. praecox), six perennials (H. angustifolius, H. atrorubens, H. rigidus, H. salicifolius, H. pauciflorus and H. resinosus), two interspecific derivatives (HIR-1734-2, RES-834-3) and two exotic lines (PI 642072, EC-537925). 相似文献
92.
An efficient, in vitro clonal propagation protocol has been established for Gardenia latifolia Ait. using mature nodal explants on Murashige and Skoog (MS) medium fortified with cytokinins (BA/Kn/2-iP) (1.0–5.0 mg l?1) in combination with auxin IAA (0.5 mg l?1). Maximum bud break (87 %) with shoot number (7.2 ± 0.26) observed on MS medium supplemented with BA (4.0 mg l?1) and IAA (0.5 mg l?1). Maximum number of shoots (30 ± 0.46) with shoot length of (0.9 ± 0.03 cm) observed on MS medium supplemented with BA (2.0 mg l?1), Kn (2.0 mg l?1) and IAA (0.5 mg l?1). Further elongation of shoots (3.5 ± 0.06 cm) was achieved on MS medium supplemented with BA (1.0 mg l?1) and IAA (0.1 mg l?1). About 70 % of root induction occurred in half-strength MS medium supplemented with IBA (4.0 mg l?1) in 4–6 weeks. Further elongation of roots with average length (9.0 cm) was achieved in culture bottles containing vermiculite and ¼ strength MS salts. After their partial hardening in these bottles for 30 days they were transferred to pots containing a mixture of soil and vermicompost (1:1) for acclimatization. The acclimatized plantlets were established in the field successfully with 85 % survival rate. 相似文献
93.
Sangappa B. Lakshmeesha Rao S. Asha S. Ganesh R. Somashekar Timma Reddy 《Fibers and Polymers》2013,14(6):1032-1039
Tassar silk fiber (Antheraea mylitta) was irradiated with the available maximum dose range upto 100 kGy using 8 MeV electron beam at room temperature. Irradiation effect in these fibers is quantified in terms of the changes in microstructural parameters studied using wide-angle X-ray scattering data (WAXS). The crystal imperfection parameters such as crystallite size (〈N〉), lattice strain (g in %), and surface weighted crystallite size (Ds in Å) have been determined by line profile analysis (LPA) using Fourier method of Warren. For this purpose, exponential, lognormal, and Reinhold functions for column length distribution have been used for the determination of these parameters. These parameters were compared with tensile properties of the fibers. The increasing trend of crystallite size values (〈N〉 as well as Ds in Å) and tenacity (gf/den) with increasing dosage of radiation clearly indicates the cross linking polymer network in fiber. Comparison of SEM photographs also confirms the X-ray results. 相似文献
94.
DN Wedlock FE Aldwell D Keen MA Skinner BM Buddle 《New Zealand veterinary journal》2013,61(5):301-306
AIMS: To determine immune responses, and the localisation and persistence of Mycobacterium bovis bacille Calmette-Guérin (BCG) in gut-associated lymphoid tissues (GALT) and other organs in possums vaccinated orally with lipid-formulated BCG vaccine. To determine the duration of excretion and longevity of survival of BCG in the faeces of vaccinated animals. METHODS: Possums (n=28) were vaccinated with lipid-formulated BCG (1 x 10 8 colony forming units (cfu) of formulated BCG) by the oral route. Control possums (n=17) were fed oral bait pellets containing formulation medium only. Possums were sacrificed at 3 days and at 1, 3, 6 and 8 weeks after vaccination or ingestion of bait. Proliferation responses to bovine purified protein derivative (PPD) were measured in lymphocytes from blood and mesenteric lymph nodes (MLN) and samples of lung, spleen, liver, MLN and Peyer's patches (PP) were cultured for the presence of BCG. The number of BCG organisms excreted in faeces and the duration of excretion were determined in eight vaccinated possums and eight control possums over a 3-week period. In a separate experiment, a further six possums were vaccinated with oral BCG vaccine (5–10 x 10 8 cfu BCG/possum) and their faeces collected over 48–72 h, for culture of BCG. The longevity of survival of BCG in these faeces was determined by storing faecal samples (n=12) under three different conditions: in an incubator (22.5°C), and conditions which simulated the forest floor and open pasture. A proportion (1–2 g) of these faecal samples was collected after storage for 1, 3, 5, 8 or 20 weeks, and cultured for BCG. RESULTS: Possums vaccinated orally with BCG vaccine showed strong proliferation responses to bovine PPD in peripheral blood lymphocytes at 6–8 weeks post-vaccination (p.v.). Positive lymphocyte proliferation assay (LPA) responses to bovine PPD were first evident in MLN at 3 weeks p.v. BCG was cultured from MLN and PP in a proportion of animals at 3–8 weeks p.v. BCG was not cultured from sections of spleen, lung or liver at any time p.v. BCG was recovered in low to moderate numbers from the faeces of vaccinated possums for up to 7 days, and maximal numbers were cultured in faeces collected 48–72 h p.v. After storage for 1 week, BCG was cultured from all faecal samples placed in the incubator and from a proportion of faeces exposed to conditions similar to those on the forest floor and pasture. With the exception of one faecal sample stored under forest floor conditions which was culture-positive for BCG at 3 and 5 weeks, BCG was not cultured from any other faecal sample stored for more than 1 week. CONCLUSIONS: Ingestion of oral BCG vaccine by possums was associated with the development of strong cell-mediated immunity in both blood and MLN. Following oral vaccination with BCG, the organisms were localised and persisted in GALT but did not spread to the spleen, liver or lungs. BCG was shed in low to moderate numbers in the faeces for up to 7 days p.v. The viability of BCG excreted in faeces decreased rapidly, particularly when faeces were exposed to an open pasture environment. Oral vaccination of possums with formulated BCG is unlikely to result in undue contamination of the environment with BCG. 相似文献
95.
Summary Semilooper resistant transgenic castor plants were produced through Agrobacterium-mediated genetic transformation method. Two castor cultivars, Jyothi and VP1 were transformed using the super-binary vector
pTOK233 carrying gus A and hpt genes. Putative transformants were regenerated following selection on the hygromycin containing medium. GUS positive primary
transformants, when subjected to Southern analysis, revealed stable integration of gus A into their genomes. In the T1 generation, a monogenic segregation ratio of 3 GUS positive: 1 GUS negative plants was observed. Furthermore, transformation
experiments were carried out with the Agrobacterium pSB111 super-binary vector carrying a synthetic delta endotoxin gene cryIAb and the herbicide resistance gene bar both driven by cauliflower mosaic virus 35S promoter. Putative transformants were regenerated through selection on the phosphinothricin
containing medium and Basta tolerant transformants were subjected to molecular analysis. PCR analysis revealed the presence
of both bar and cryIAb genes in the Basta tolerant primary transformants. Southern analysis of PCR positive plants with cryIAb probe showed a 3 Kb band upon HindIII digestion and a > 6 Kb band with BamHI digestion, thus suggesting stable integration of cryIAb intact expression cassette and independent nature of the transformants. The primary transformants subjected to ELISA disclosed
varied levels of Cry protein. These transgenics expressing cryIAb – when bioassayed against freshly hatched semilooper larvae – induced substantial (> 88%) insect mortality. Southern analysis
of 2T1 plants revealed the presence of cryIAb gene, indicating stable inheritance of the transgene into the next generation. In T1, all the Southern-positive plants for cryIAb invariably exhibited tolerance to Basta, denoting co-segregation of both bar and cryIAb genes. Transgenics, expressing cryIAb exhibited ample resistance against the castor semilooper. 相似文献
96.
Aviram M Volkova N Coleman R Dreher M Reddy MK Ferreira D Rosenblat M 《Journal of agricultural and food chemistry》2008,56(3):1148-1157
We have analyzed in vivo and in vitro the antiatherogenic properties and mechanisms of action of all pomegranate fruit parts: peels (POMxl, POMxp), arils (POMa), seeds (POMo), and flowers (POMf), in comparison to whole fruit juice (PJ). Atherosclerotic E 0 mice consumed POM extracts [200 microg of gallic acid equivalents (GAE)/mouse/day] for 3 months. Blood samples, peritoneal macrophages (MPM), and aortas were then collected. All POM extracts possess antioxidative properties in vitro. After consumption of PJ, POMxl, POMxp, POMa, or POMf by E (0) mice, the atherosclerotic lesion area was significantly decreased by 44, 38, 39, 6, or 70%, respectively, as compared to placebo-treated group, while POMo had no effect. POMf consumption reduced serum lipids, and glucose levels by 18-25%. PJ, POMxl, POMxp, POMf, or POMa consumption resulted in a significant decrement, by 53, 42, 35, 27, or 13%, respectively, in MPM total peroxides content, and increased cellular paraoxonase 2 (PON2) activity, as compared to placebo-treated mice. The uptake rates of oxidized-LDL by E (0)-MPM were significantly reduced by approximately 15% after consumption of PJ, POMxl, or POMxp. Similar results were obtained on using J774A.1 macrophage cell line. Finally, pomegranate phenolics (punicalagin, punicalin, gallic acid, and ellagic acid), as well as pomegranate unique complexed sugars, could mimic the antiatherogenic effects of pomegranate extracts. We conclude that attenuation of atherosclerosis development by some of the POM extracts and, in particular, POMf, could be related to the combined beneficial effects on serum lipids levels and on macrophage atherogenic properties. 相似文献
97.
Bellaloui N Zablotowicz RM Reddy KN Abel CA 《Journal of agricultural and food chemistry》2008,56(8):2765-2772
Previous research has demonstrated that glyphosate can affect nitrogen fixation or nitrogen assimilation in soybean. This 2-year field study investigated the effects of glyphosate application of 1.12 and 3.36 kg of ae ha(-1) on nitrogen metabolism and seed composition in glyphosate-resistant (GR) soybean. There was no effect of glyphosate application on nitrogen fixation as measured by acetylene reduction assay, soybean yield, or seed nitrogen content. However, there were significant effects of glyphosate application on nitrogen assimilation, as measured by in vivo nitrate reductase activity (NRA) in leaves, roots, and nodules, especially at high rate. Transiently lower leaf nitrogen or (15)N natural abundance in high glyphosate application soybean supports the inhibition of NRA. With the higher glyphosate application level protein was significantly higher (10.3%) in treated soybean compared to untreated soybean. Inversely, total oil and linolenic acid were lowest at the high glyphosate application rate, but oleic acid was greatest (22%) in treated soybean. These results suggest that nitrate assimilation in GR soybean was more affected than nitrogen fixation by glyphosate application and that glyphosate application may alter nitrogen and carbon metabolism. 相似文献
98.
Jose Antony Appidi Krishna Reddy Arun Sudhagar Hari Krishna Vungurala Luke A Roy 《Journal of the World Aquaculture Society》2021,52(1):155-170
The suitability of inland saline groundwater as a medium to culture juvenile cobia, Rachycentron canadum, was assessed. In the first experiment, juvenile cobia stocked in raw (unamended) saline groundwater at salinities of 5, 10, and 15 g/L exhibited complete mortality after 108, 176, and 195 hr, respectively. The second experiment evaluated the rearing of juvenile cobia (mean weight ~9.23 ± 0.12 g) in potassium (K+)‐amended saline groundwater (100% K+ fortified) and reconstituted seawater at salinities of 5, 10, and 15 g/L to assess growth and osmoregulation in distinct culture media. Following 60 days of culture, all fish survived the experimental period. Final mean bodyweight of cobia reared in K+‐amended saline groundwater (103.2–115.8 g) and seawater (111.2–113.8 g) of different salinities did not vary significantly (p > .05). No differences (p > .05) were observed in specific growth rate, weight gain (%), and feed conversion ratio between treatment groups. Serum osmolality increased with salinity and was significantly higher (p < .05) for fish in K+‐amended saline groundwater (353–361 mOsmol/Kg) than in reconstituted seawater (319–332 mOsmol/Kg), although differences were not observed between salinities by water type. Cobia stocked in saline groundwater of different salinities were osmoregulating normally, and the higher values observed may be because of variations in ionic composition and other interfering ions in saline groundwater. Trial results suggest that juvenile cobia can achieve optimal growth in K+‐amended saline groundwater of low and intermediate salinities. 相似文献
99.
100.
Kaushal Kishore Upreti Ravindra Mohan Bhatt Periyasamy Panneerselvam Lakki Reddy Varalakshmi 《International Journal of Fruit Science》2016,16(2):191-209
Effects of arbuscular mycorrhizal fungi (AMF) alone or in combination with bacterial consortium (AMF+BC) inoculation prior to induced salinity (NaCl @ 150 or 250 mM) were studied on root growth; plant biomass; leaf area; Na+ and K+ contents; leaf water potential (Ψw); osmotic potential (Ψπ); photosynthesis rate (Pn); and contents of chlorophyll, phytohormones, and polyamines in the grape rootstock ‘Dogridge’, popular among Indian vine growers. AMF inoculation in the NaCl untreated rootstocks plants increased root growth, root and shoot biomass, and leaf area and improved leaf Ψw, Ψπ, Pn, and chlorophyll content, and also countered the stress-induced decline in the NaCl treated plants. The abscisic acid (ABA), cytokinins, and polyamine-spermidine and spermine contents in the leaves of NaCl untreated or treated were significantly increased by the AMF inoculation. Among the treatments, AMF with BC was relatively more effective than AMF alone with respect to changes in above morpho-physiological characters. The results depicted that AMF (AMF alone or AMF+BC) inoculation significantly improved salinity tolerance of grape rootstock and tolerance is induced by improvements in plant water balance, K+:Na+ ratio, and Pn, besides distinct accumulations in ABA and polyamines-spermine and spermidine. The above findings have potential in suggesting the AMF usefulness in improving the efficacy of ‘Dogridge’ rootstock in grape cultivation under salt affected soils. 相似文献