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Bemisia tabaci Phylogenetic Groups in India and the Relative Transmission Efficacy of Tomato leaf curl Bangalore virus by an Indigenous and an Exotic Population 被引量:8
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作者 R V Chowda-Reddy M Kirankumar +4 位作者 Susan E Seal V Muniyappa Girish B Valand M R govindappa John Colvin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第2期235-248,共14页
Bemisia tabaci adults from various host-plant species were collected from 31 regions across India.266 B.tabaci samples were first screened by RAPD-PCR to examine molecular variability and to select individuals with di... Bemisia tabaci adults from various host-plant species were collected from 31 regions across India.266 B.tabaci samples were first screened by RAPD-PCR to examine molecular variability and to select individuals with different fingerprints.Host-plant and region of collection were then used to select 25 individuals for PCR amplification and sequencing of their partial mitochondrial cytochrome oxidase subunit one(mtCOI)genes.Pairwise comparisons with mtCOI consensus sequences showed that the majority of these samples had 〈3.5% sequence divergence from groups currently termed Asia I,Asia II-5,Asia II-7,and Asia II-8.The biotype-B B.tabaci from India clustered into the Middle East-Asia Minor 1 group.A new group of B.tabaci from Coimbatore,collected from pumpkin,was related most closely to the Asia I group(6.2% sequence divergence from the consensus Asia I sequence).To increase our understanding of the epidemiology of tomato leaf curl disease(ToLCD)and the key B.tabaci genetic groups involved in virus spread,the indigenous Asia I and the exotic biotype-B population from South India were used to carry out transmission experiments using Tomato leaf curl Bangalore virus(ToLCBV).The acquisition access periods(AAP),inoculation access periods(IAP),latent periods(LP),and ToLCBV transmission efficiencies of the two populations were compared and the biotype-B had the more efficient transmission characteristics.These results are discussed in relation to recent changes in the epidemiology of tomato leaf curl disease in South India. 展开更多
关键词 BEGOMOVIRUSES mitochondrial cytochrome oxidase WHITEFLY Bemisia tabaci virus-vector relationships epidemiology
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<i>In Vitro</i>Anti-HIV Activity of Partially Purified Coumarin(s) Isolated from Fungal Endophyte, <i>Alternaria</i>Species of <i>Calophyllum inophyllum</i> 被引量:1
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作者 Melappa govindappa Kavya C. Hemmanur +3 位作者 S. Nithin Chandrappa Chinna Poojari Gopalakrishna Bhat K. Channabasava 《Pharmacology & Pharmacy》 2015年第7期321-328,共8页
5 totally different endophytic fungal species were isolated from bark and leaf parts of Calophyllum inophyllum. Leaf part yielded Trichoderma harzianum and Alternaria species, whereas bark showed the presence of Fusar... 5 totally different endophytic fungal species were isolated from bark and leaf parts of Calophyllum inophyllum. Leaf part yielded Trichoderma harzianum and Alternaria species, whereas bark showed the presence of Fusarium species, Aspergillus species and unidentified fungi. Two solvents (hexane and methanol) were used for endophytic fungal extraction and the Alternaria species had shown the presence of coumarin whereas Trichoderma harzianum in methanol extract and Fusarium species in hexane extract had shown the coumarin(s) in all the four methods tested. The total coumarin yield was more in microwave assistance method, the methanol Alternaria species (3.941 ± 0.082) stood first, followed by hexane extract of Alternaria species (3.254 ± 0.082), Fusarium species (2.532 ± 0.082) and Trichoderma harzianum (2.294 ± 0.082), the plant extract showed 4.149 + 0.053. The methanol extract of Alternaria species inhibited the activity of HIV-Reverse Transcriptase (RT) (82.81 ± 1.0), integrase (98%) and protease (78) in maximum level followed by hexane extract of Alternaria species (71.12 ± 0.9, 89, 68), Fusarium species (63.92 ± 1.8, 67, 66) and Trichoderma harzianum (56.69 ± 0.9, 71, 63). The endophytic fungi Alternaria species inhibited all the three viral enzymes at maximum level and it was more than standard drug. However, in order to know possible anti-HIV, it is necessary to isolate active coumarin from the Alternaria species and the mechanism of action will be studied in future studies. 展开更多
关键词 ENDOPHYTES ALTERNARIA SPECIES HIV-RT INTEGRASE Protease Inhibitory Activity
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Functional recovery and muscle atrophy in pre-clinical models of peripheral nerve transection and gap-grafting in mice:effects of 4-aminopyridine
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作者 Jung Il Lee M A Hassan Talukder +8 位作者 Zara Karuman Anagha A.Gurjar Prem Kumar govindappa Jagadeeshaprasad M.Guddadarangaiah Kristen M.Manto Grant D.Wandling John P.Hegarty David L.Waning John C.Elfar 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期439-444,共6页
We recently demonstrated a repurposing beneficial effect of 4-aminopyridine(4-AP),a potassium channel blocker,on functional recove ry and muscle atrophy after sciatic nerve crush injury in rodents.However,this effect ... We recently demonstrated a repurposing beneficial effect of 4-aminopyridine(4-AP),a potassium channel blocker,on functional recove ry and muscle atrophy after sciatic nerve crush injury in rodents.However,this effect of 4-AP is unknown in nerve transection,gap,and grafting models.To evaluate and compare the functional recovery,nerve morphology,and muscle atrophy,we used a novel stepwise nerve transection with gluing(STG),as well as 7-mm irreparable nerve gap(G-7/0)and 7-mm isografting in 5-mm gap(G-5/7)models in the absence and presence of 4-AP treatment.Following surgery,sciatic functional index was determined wee kly to evaluate the direct in vivo global motor functional recovery.After 12 weeks,nerves were processed for whole-mount immunofluorescence imaging,and tibialis anterior muscles were harvested for wet weight and quantitative histomorphological analyses for muscle fiber crosssectional area and minimal Feret's diameter.Average post-injury sciatic functional index values in STG and G-5/7 models were significantly greater than those in the G-7/0 model.4-AP did not affect the sciatic functional index recovery in any model.Compared to STG,nerve imaging revealed more misdirected axons and distorted nerve architecture with isografting.While muscle weight,cross-sectional area,and minimal Feret's diameter were significantly smaller in G-7/0 model compared with STG and G-5/7,4-AP treatment significantly increased right TA muscle mass,cross-sectional area,and minimal Feret's diameter in G-7/0 model.These findings demonstrate that functional recovery and muscle atrophy after peripheral nerve injury are directly related to the intervening nerve gap,and 4-AP exerts diffe rential effects on functional recove ry and muscle atrophy. 展开更多
关键词 4-AMINOPYRIDINE functional recovery muscle atrophy nerve gap nerve grafting nerve imaging nerve transection
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Large Foreign Body in the Nasal Cavity, Maxillary Sinus and Infratemporal Fossa—Atypical Presentation
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作者 Subrat Kumar Behera Niranjan Mishra Sharath govindappa 《International Journal of Otolaryngology and Head & Neck Surgery》 2014年第6期371-375,共5页
A 59-year-old male presented with complaints of trismus and discharge of altered blood from nose for 1 year. Patient had a history of facial trauma one year back. Nasal endoscopy and CT scan revealed a foreign body lo... A 59-year-old male presented with complaints of trismus and discharge of altered blood from nose for 1 year. Patient had a history of facial trauma one year back. Nasal endoscopy and CT scan revealed a foreign body lodged in posterior half of both nasal cavity, left maxillary sinus and left infratemporal fossa penetrating the walls of maxillary sinus and nasal septum. Foreign body was removed by infratemporal fossa approach. This case has a rare location of a forgotten foreign body with atypical presentation. 展开更多
关键词 Foreign Body NOSE and PARANASAL SINUSES Infratemporal Fossa TRISMUS
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Socio-Economic and Scientific Impact Created by Whitefly-Transmitted,Plant-Virus Disease Resistant Tomato Varieties in Southern India
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作者 John Colvin N Nagaraju +7 位作者 Carlos Moreno-Leguizamon R M govindappa T B Manjunatha Reddy S A Padmaja Neena Joshi Peter M Hanson Susan E Seal V Muniyappa 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第2期337-345,共9页
Research carried out to assess the impact of open-pollinated Tomato leaf curl virus(ToLCV)-resistant tomatoes and hybrids on the livelihoods of resource-poor farmers in Southern India is described and discussed.Thre... Research carried out to assess the impact of open-pollinated Tomato leaf curl virus(ToLCV)-resistant tomatoes and hybrids on the livelihoods of resource-poor farmers in Southern India is described and discussed.Three high-yielding ToLCV-resistant tomato varieties were developed initially using conventional breeding and screening techniques involving inoculation by ToLCV-viruliferous whitefly,Bemisia tabaci.In 2003 and 2004,respectively,these varieties were released officially by the Karnataka State Seed Committee and the Indian Ministry of Agriculture through notification in the Gazette of India.From 2003 to 2005,eleven seed companies bought breeder seed of the ToLCV-resistant varieties and used them to begin breeding F1 hybrids from them.Socio-economic studies carried out to assess the benefits obtained from growing the ToLCV-resistant varieties found that farmers could gain up to 10 times the profit by growing the ToLCV-resistant varieties compared to the pre-existing ToLCV-susceptible varieties.Adoption of ToLCV-resistant tomatoes was also associated with reduced pesticide use.Extra income from tomato sales was prioritised by farmers to pay for children's education,better nutrition and medicines.In a joint effort with the commercial seed sector in India,a promotional field day was organised in 2007.As well as the three ToLCV-resistant varieties,62 ToLCV-resistant hybrid tomatoes were exhibited during a farmer-field day by 17 commercial seed companies and several public institutes.Tomatoes with ToLCV-resistance are now grown widely in South India and seeds of the three open-pollinated varieties have been distributed to more than 12 countries.In 2007,a conservative estimate of the financial-benefit to cost of the research ratio was already more than 837:1. 展开更多
关键词 Bemisia tabaci BEGOMOVIRUS international development TOMATO resistance Tomato leaf curl virus
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Shear-Controlled Gold Mineralization of G. R. Halli Area of Chitradurga Schist Belt, Dharwar Craton: Insights from Fluid Inclusion Study
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作者 govindappa Gopalakrishna Mohamed Shareef Poorigali Chowdaiah Nagesh 《Open Journal of Geology》 2018年第7期662-673,共12页
Gold mineralization at G. R. Halli is located along the Central shear zone of Chitradurga schist belt, extending from west of Gonur, through east of G. R. Halli and C. K. Halli to east of Honnemardi, roughly parallel ... Gold mineralization at G. R. Halli is located along the Central shear zone of Chitradurga schist belt, extending from west of Gonur, through east of G. R. Halli and C. K. Halli to east of Honnemardi, roughly parallel to stratigraphic units. The NNW-SSE trending shear zone has a width of 0.5 to 1.5 km shows extensive carbonatization of metabasalts and the associated lithologies confined to NNW-WNW trending arcuate brittle-ductile zone. The sheared and silicified contact zones between carbonaceous argillite and schistose metabasalt form the potential sites for localization of mineralization. The gold is associated with sulphides mainly pyrite, arsenopyrite, galena, sphalerite, minor chalcopyrite. Textural relationship indicates two stage sulphide mineral assemblages co-relatable with two stage fluid ascents having temperature of homogenization between 125&#176;C and 256&#176;C. It is a typical epigenetic lode gold system, which got affected by later deformation. 展开更多
关键词 G. R. Halli Chitradurga SCHIST BELT Dharwar CRATON
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Electrochemical Generation of Cubic Shaped Nano Zn_2SnO_4 Photocatalysts 被引量:5
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作者 Chandrappa K.govindappa Venkatesha T.Venkatarangaiah Sharifah B.Abd Hamid 《Nano-Micro Letters》 SCIE EI CAS 2013年第2期101-110,共10页
In this contribution, an efficient and simple two-step hybrid electrochemical-thermal route was developed for the synthesis of cubic shaped Zn_2SnO_4 (ZTO) nanoparticles using aqueous sodium bicarbonate(NaHCO_3) and s... In this contribution, an efficient and simple two-step hybrid electrochemical-thermal route was developed for the synthesis of cubic shaped Zn_2SnO_4 (ZTO) nanoparticles using aqueous sodium bicarbonate(NaHCO_3) and sodium stannate(Na_2SnO_3) electrolyte. The sacrificial Zn was used as anode and cathode in an undivided cell under galvanostatic mode at room temperature. The bath concentration and current density were respectively varied from 30 to 120 mmol and 0.05 to 1.5 A/dm^2. The electrochemically generated precursor was calcined for an hour at different range of temperature from 60 to 600. The crystallite sizes in the range of 24-53 nm were calculated based on Debye-Scherrer equation. Scanning electron microscope and transmission electron microscopy results reveal that all the particles have cubic morphology with diameter of40-50 nm. The as-prepared ZTO samples showed higher catalytic activity towards the degradation of methylene blue(MB) dye, and 90% degradation was found for the sample calcined at 600, which is greater than that of commercial TiO_2-P25 photocatalysts. The photodegradation efficiency of ZTO samples was found to be a function of exposure time and the dye solution p H value. These results indicate that the ZTO nanoparticles may be employed to remove dyes from wastewater. 展开更多
关键词 ELECTROCHEMISTRY Zn2SnO4 PHOTOCATALYST CUBIC NANOPARTICLE
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Antioxidant Activity and Phytochemical Screening of Crude Endophytes Extracts of <i>Tabebuia argentea</i>Bur. &K. Sch.
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作者 M. govindappa R. Channabasava +1 位作者 K. R. Sunil Kumar K. C. Pushpalatha 《American Journal of Plant Sciences》 2013年第8期1641-1652,共12页
The aim of this study is to investigate in vitro antioxidant activities and the phytochemical screening endophytes. Seven different endophytic fungi were isolated from different parts of the plant and their extracts s... The aim of this study is to investigate in vitro antioxidant activities and the phytochemical screening endophytes. Seven different endophytic fungi were isolated from different parts of the plant and their extracts subjected to know antioxidant properties and phytochemical screening. Phytochemical analysis revealed the presence of tannins, flavonoids, steroids, alkaloids, phenols and proteins from different solvents extracts of different endophytes. The antioxidant activity was evaluated by six separated methods: scavenging of free radical DPPH, FRAP, TBA, superoxide radical, FTC and iron methods. All seven different endophytes yielded almost all phytochemicals in methanol extracts which were tested. The endophytes A. niger, Penicillium sp. and Trichoderma sp. have shown potential in vitro antioxidant activities. Further work is needful to isolate the exact compound which is responsible for antioxidant activity and biophysical characterization will be done in the future. 展开更多
关键词 TABEBUIA argentea ENDOPHYTES Antioxidant Activity PHYTOCHEMICALS
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