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991.
A. A. Khan R. Sharma B. Afreen Q. A. Naqvi S. Kumar S. K. Snehi S. K. Raj 《Phytoparasitica》2011,39(2):199-203
Natural occurrence of mosaic disease was observed on basil (Ocimum sanctum L.) in Aligarh, U. P., India, during 2008. The disease could be transmitted by sap inoculations from naturally infected O. sanctum to O. sanctum and some test plant species. Cucumber mosaic virus (CMV) was detected by RT-PCR using coat protein gene specific primers of CMV (Acc. AM180922 & AM180923), which resulted in
the expected size ~650 bp amplicon in infected samples. The amplicon was cloned, sequenced and data were deposited in GenBank
Acc. EU600216. The sequence data analysis revealed 97–99% identities at both nucleotide and amino acid levels with the CMV
strains of subgroup II reported worldwide. Based on the high sequence identities and close phylogenetic relationships with
CMV subgroup II strains, the virus under study has been identified as a new isolate of CMV subgroup II and designated as CMV-Basil. 相似文献
992.
A new genus, Ritacestus, is proposed to accommodate Ritacestus ritaii (Verma, 1926) comb. n. (syn. Proteocephalus ritaii), a parasite of the catfish Rita rita (Hamilton) in India. The new genus, which is placed in the Gangesiinae, is characterized by (i) a small, subspherical scolex formed by four large lobes separated from one another by longitudinal grooves, with a large, widely oval to pyriform rostellum-like apical organ, larger than suckers and possessing an apical hemispherical depression; (ii) paramuscular and cortical position of some vitelline follicles (most follicles are situated medullary); (iii) ventral and dorsal bands of vitelline follicles usually uninterrupted ventral to terminal genitalia and reaching to the posterior margin of proglottides; (iv) the vagina always anterior to the cirrus-sac; (v) a large size of the body (length up to 51 cm); and (vi) development of the uterus of type 2. In its morphology, especially shape of the scolex and apical organ, and paramuscular and cortical position of some vitelline follicles, Ritacestus resembles Postgangesia Akhmerov, 1969, but differs in the presence of a genital atrium (both genital pores of Postgangesia are separate), the anterior position of the vagina (almost always posterior in the latter genus), position of vitelline follicles in cross sections (dorsal and ventral bands in Ritacestus versus only a lateral band in the latter genus), and dorsal excretory canals indistinguishable in mature and gravid proglottides of R. ritaii (well developed in Postgangesia spp.). The type and only species of the genus, R. ritaii, is redescribed on the basis of new material from the type host from the Ganges River basin in India and its neotype is designated. 相似文献
993.
BACKGROUND: The cotton bollworm, Helicoverpa armigera (Hübner), is one of the most serious insect pests of cotton. It has developed resistance to almost all groups of chemical insecticides because of their intensive use. The failure of insecticides to control H. armigera has been a strong incentive for the adoption of transgenic cotton (Bt cotton). However, the value of Bt could be diminished by widespread resistance development to Bt toxins in insect populations. Therefore, understanding the genetic basis of resistance is essential for developing and implementing strategies to delay and monitor resistance. RESULTS: A resistant strain designated as BM‐R was obtained from the cross of adults from Bathinda () and Muktsar (), Punjab, India, which showed the highest survival (60.68%) and LC50 value (1.396 µg mL?1 diet). Similarly, a laboratory‐maintained strain from Hoshiarpur, Punjab, showed maximum susceptibility to Cry1Ac toxin with the lowest LC50 value (0.087 µg mL?1), and was designated as HP‐S. The genetic purity of both strains was confirmed by RAPD profile analysis at each generation, and genetic similarity reached more than 90% after the third generation. Continuous maintenance of the resistant BM‐R strain on Cry1Ac resulted in an increase in LC50 from 0.531 µg mL?1 in F0 to 4.28 µg mL?1 in F14 and 7.493 µg mL?1 in F19, while the LC50 values for HP‐S larvae on diet without Cry1Ac increased to 0.106 and 0.104 µg mL?1, which lay within the fiducial limits of the baseline LC50 value. The mode of inheritance of resistance was elucidated through bioassay response of resistant, susceptible heterozygotes and backcross progeny to Cry1Ac incorporated in semi‐synthetic diet. CONCLUSION: Based on dominance, degree of dominance and backcross values, resistance was inferred to be polygenic, autosomal and inherited as a recessive trait. Copyright © 2011 Society of Chemical Industry 相似文献
994.
995.
Ramirez-Coronel MA Marnet N Kolli VS Roussos S Guyot S Augur C 《Journal of agricultural and food chemistry》2004,52(5):1344-1349
Fresh and 3-day-old coffee pulp of the Arabica variety were analyzed for polyphenol composition followed by characterization by two different methods. The first method consisted in subjecting coffee pulp powder to direct thiolysis. For the second method, coffee pulp was subjected to successive solvent extractions, followed by thiolysis. Quantification of phenolic compounds was then achieved by high-performance liquid chromatography (HPLC) analysis of thiolysis products. Four major classes of polyphenols were identified: flavan-3-ols (monomers and procyanidins), hydroxycinnamic acids, flavonols, and anthocyanidins. Differences in concentration of procyanidins were observed between fresh and 3-day-old coffee pulp. Constitutive units were mainly epicatechin, representing more than 90% of the proanthocyanidin units, with average degrees of polymerization in the range of 3.8-9.1. Monomer to hexamer units of flavan-3-ols from fresh coffee pulp were separated by normal-phase HPLC. Molecular size of oligomeric proanthocyanidins was obtained by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Results obtained confirm the presence of oligomers of the flavan-3-ol (-)-epicatechin. 相似文献
996.
A 5-m-wide soil pit at the base of a forested hillslope in coastal British Columbia was instrumented for studying subsurface flow processes during rainstorms. Three typical, low-intensity autumn rainfall events with different antecedent moisture conditions are assessed. Outflow from the organic horizon was captured and measured by a single trough, and outflow from the mineral horizon (above compact glacial till and bedrock) was measured separately for three adjacent sections of the soil pit. For two storms that were preceded by dry conditions, lateral outflow from the organic horizon occurred, although the water table did not rise up to the organic horizon. However, the calculated effective contributing area was small (<0.7 m2) and the effective contributing slope length was short (<0.15 m). Furthermore, volumes of outflow from the organic horizon during these storms were more than 400 times less than during a later storm with wet antecedent conditions. During this later storm, a portion of the outflow from the organic horizon may have been generated as saturated overland flow due to the rising water table. The calculated effective contributing area (>170 m2) and the effective contributing slope length (>36 m) were substantially greater for the “wet” antecedent storm compared to the “dry” storm events. Shallow lateral flow over unsaturated soil is therefore unlikely to be a significant contributor to storm runoff at such forested sites. Flow at the organic horizon–mineral soil interface may contribute to interconnected preferential flow pathways during wetter antecedent conditions. 相似文献
997.
Solvent-free lipase-catalyzed preparation of diacylglycerols 总被引:6,自引:0,他引:6
Various methods have been applied for the enzymatic preparation of diacylglycerols that are used as dietary oils for weight reduction in obesity and related disorders. Interesterification of rapeseed oil triacylglycerols with commercial preparations of monoacylglycerols, such as Monomuls 90-O18, Mulgaprime 90, and Nutrisoft 55, catalyzed by immobilized lipase from Rhizomucor miehei (Lipozyme RM IM) in vacuo at 60 degrees C led to extensive (from 60 to 75%) formation of diacylglycerols. Esterification of rapeseed oil fatty acids with Nutrisoft, catalyzed by Lipozyme RM in vacuo at 60 degrees C, also led to extensive (from 60 to 70%) formation of diacylglycerols. Esterification of rapeseed oil fatty acids with glycerol in vacuo at 60 degrees C, catalyzed by Lipozyme RM and lipases from Thermomyces lanuginosus (Lipozyme TL IM) and Candida antarctica (lipase B, Novozym 435), also provided diacylglycerols, however, to a lower extent (40-45%). Glycerolysis of rapeseed oil triacylglycerols with glycerol in vacuo at 60 degrees C, catalyzed by Lipozyme TL and Novozym 435, led to diacylglycerols to the extent of =50%. Repeated use of Lipozyme RM in the esterification of rapeseed oil fatty acids with Monomuls resulted in minor reduction of its activity. The products of esterification of rapeseed oil fatty acids with Monomuls and glycerol yielded upon short-path vacuum distillation residues (diacylglycerol oils) containing 66-70% diacylglycerols. 相似文献
998.
QTL analysis for grain weight in common wheat 总被引:6,自引:0,他引:6
Neeraj Kumar Pawan L. Kulwal Anupama Gaur Akhilesh K. Tyagi Jitendra P. Khurana Paramjit Khurana Harindra S. Balyan Pushpendra K. Gupta 《Euphytica》2006,151(2):135-144
Quantitative trait loci (QTL) analysis for grain weight (GW = 1000 grain weight) in common wheat was conducted using a set of 100 recombinant inbred lines (RILs) derived from a cross ‘Rye Selection 111 (high GW) × Chinese Spring (low GW)’. The RILs and their two parental genotypes were evaluated for GW in six different environments (three locations × two years). Genotyping of RILs was carried out using 449 (30 SSRs, 299 AFLP and 120 SAMPL) polymorphic markers. Using the genotyping data of RILs, framework linkage maps were prepared for three chromosomes (1A, 2B, 7A), which were earlier identified by us to carry important/major genes for GW following monosomic analysis. QTL analysis for GW was conducted following genome-wide single marker regression analysis (SMA) and composite interval mapping (CIM) using molecular maps for the three chromosomes. Following SMA, 12 markers showed associations with GW, individual markers explaining 6.57% to 10.76% PV (phenotypic variation) for GW in individual environments. The high grain weight parent, Rye Selection111, which is an agronomically superior genotype, contributed favourable alleles for GW at six of the 12 marker loci identified through SMA. The CIM identified two stable and definitive QTLs, one each on chromosome arms 2BS and 7AS, which were also identified through SMA, and a third suggestive QTL on 1AS. These QTLs explained 9.06% to 19.85% PV for GW in different environments. The QTL for GW on 7AS is co-located with a QTL for heading date suggesting the occurrence of a QTL having a positive pleiotropic effect on the two traits. Some of the markers identified during the present study may prove useful for marker-assisted selection, while breeding for high GW in common wheat. 相似文献
999.
With a long‐term plan to develop transgenic pigeonpea with resistance to fungal disease, the transfer of a rice chitinase gene to pigeonpea [Cajanus cajan (L.) Millsp.] is reported here. The rice chitinase gene harboured in the plasmid pCAMBIA 1302:RChit was delivered via the Agrobacterium‐mediated method to the cotyledonary node explants followed by subsequent regeneration of complete plants on selection media containing hygromycin. Putative transformed pigeonpea plants were recovered with stringent selection pressure and confirmed using molecular techniques. Stable integration and expression of the chitinase gene has been confirmed in the T0 and T1 transgenics through molecular analysis. 相似文献
1000.
Simple sequence repeat markers for botanical varieties of cultivated peanut (Arachis hypogaea L.) 总被引:1,自引:0,他引:1
Guohao He Ronghua Meng Hui Gao Baozhu Guo Guoqing Gao Melanie Newman Roy N Pittman C. S. Prakash 《Euphytica》2005,142(1-2):131-136
Cultivated peanut (Arachis hypogaea L.) consists of six botanical varieties. Identification of DNA markers associated with botanical varieties would be useful in plant genotyping, germplasm management, and evolutionary studies. We have developed 130 simple sequence repeat (SSR) markers in peanut, 38 of which were used in this study because of their ability in detecting genetic polymorphism among 24 peanut accessions. Eight SSR markers were found useful to classify botanical varieties. Among them, six SSR markers were specific to botanical varieties fastigiata and vulgaris, one to botanical varieties hypogaea and hirsuta, and one to botanical varieties peruviana, and aequatoriana. Also, three of them derived from peanut expressed sequence tags (ESTs) were associated with putative genes. As botanical varieties have different morphological traits and belong to different subspecies in A. hypogaea, these markers might be associated with genes involved in the expression of morphological traits. The results also suggested that SSRs (also called microsatellites) might play a role in shaping evolution of cultivated peanut. Multiplex PCR of botanical variety-specific markers could be applied to facilitate efficient genotyping of the peanut lines. 相似文献