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American cotton [Gossypium hirsutum (L.)] grown in India belongs to the race Latifolium. It is prone to bollworms [Helicoverpa armigera (Hubner), Erias vitella (Fabricius), Pectinophora gossypiella (Saunders)] infestation which causes considerable crop loss. Two breeding lines ‘Bikaneri (BN)‐arboreum (ARB)‐16’ and ‘BN‐tomentosum (TOM)‐277’ are cytoplasmic diverse genetic stocks. They were developed by crossing experimental lines ‘Delta Branch Experiment Station (DES)‐ARB16’ and ‘DES‐TOM277’ (non‐recurrent parents) with G. hirsutum‘BN’ (recurrent parent). Compared with BN these stocks possessed higher amount of gossypol, flavonol and phenol contents in leaves, stem and square. Plants were tolerant to bollworms and inherited comparable agronomic properties (yield, boll weight, plant height, number of monopods and sympods and fibre quality). Cotton breeders can use these lines for breeding cotton resistant to bollworm.  相似文献   
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Anthracnose is a serious disease affecting dry bean production especially in the cool highland areas worldwide. The objective of this research was to study the inheritance of anthracnose resistance in market-class dry beans. A complete diallel set of crosses was generated from nine diverse parents comprising six resistant and three susceptible to anthracnose. The F1 and F2 crosses and parents were artificially inoculated with Colletotriclum lindenumthianum Race-767 in a growth room. There was significant variation for anthracnose resistance among genotypes. General combining ability (GCA) and specific combining ability effects were significant for resistance, indicating importance of both additive and non-additive effects, respectively. Preponderance of GCA effects (66%) suggested that additive effects were more important than non-additive effects (24%), which were also reflected by high heritability estimates (70%), and suggested that simple selection or backcrossing would be useful for improving the resistance in market class varieties. The study was not conclusive on whether epistatic gene action played a major role, but if available it might have biased the dominance gene effects. Reciprocal effects (10%) were not significant (P > 0.05), suggesting that cytoplasmic genes did not play a major role in modifying anthracnose resistance. Parental lines G2333, AB136, NAT002, and NAT003 showed highly negative GCA effects qualifying them as suitable parents for transferring resistance genes to their progenies. A few major genes, 1–3, displaying partial dominance conditioned anthracnose resistance, suggesting a possibility of using marker-assisted selection to improve anthracnose resistance in market-class dry beans.  相似文献   
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Outer membrane proteins (OMP) of P. multocida (serotype B:2) field isolates (n = 6) and a vaccine strain (P-52) were extracted by a sarkosyl method and characterized using SDS-PAGE and immunoblotting. About 20 polypeptide bands were observed in the profile of the vaccine strain with MW ranging from 16 to 90 kDa and, based on band thickness and intensity of staining, three polypeptides of MW 31, 33 and 37 kDa were considered to be the major OMPs. The profiles of the field isolates showed minor differences when compared with that of the vaccine strain. The OMP of 33 kDa was only expressed by the vaccine strain. Four field isolates expressed an OMP of 39 kDa, which did not appear in the profiles of the remaining two field isolates and the P-52 strain. Similarly, an OMP of 25 kDa was exclusively seen in the profile of a single isolate. By immunoblotting studies, using anti-P. multocida (P-52) whole-cell hyperimmune serum raised in rabbits as well as buffalo immune sera, it became evident that the polypeptide of 37 kDa was the most antigenic OMP in the profiles of all the isolates, including the P-52 strain. Other polypeptides were either weakly antigenic or visible in the profile of only a few of the isolates. The study thus identified the major OMP of P. multocida (B:2) and suggested that this highly antigenic 37 kDa OMP has potential for further protective and immunodiagnostic studies.  相似文献   
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We report the spontaneous formation of uniformly distributed arrays of "tips" (tall conical hillocks) upon oxidation of palladium (Pd) thin films. The formation of the palladium oxide tips depended on the thickness and granularity of the Pd film and on annealing and oxidation conditions. As the Pd film thickness increased from 40 to 200 nanometers, the average height of the tips increased from 0.5 to 1.2 micrometers, their height distribution became broader, and their density decreased from 55 x 10(6) to 12 x 10(6) per square centimeter. Enhanced photoelectron emission from locations corresponding to the tips suggests their possible use in field emission applications.  相似文献   
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Incidence of sucking pests was studied in a transgenic (Bt) and non-transgenic cotton (non-Bt) agro ecosystem in 2008 and 2009. Simultaneously, the influence of different pesticides applied in two different methods on sucking pests and generalist predators was investigated on transgenic cotton. In stem application, the insecticides solutions prepared were painted directly on the middle portion of the plant stem but in foliar application the recommended dosages of the insecticides were sprayed on the cotton plant. The transgenic and non-transgenic cotton did not differ significantly in the population of sucking pests. The different pesticides when applied by foliar sprays reduced significantly more sucking pests than stem application. Among the different insecticides used, imidacloprid caused the maximum reduction of the leaf hopper population, acetamiprid caused the maximum whitefly reduction, and clothianidin caused the maximum thrips reduction under foliar application. Via stem application, acetamiprid and thiomethoxam were found better in suppression of the sucking pests?? population, but the population of predators was significantly less disrupted by the stem application method. The foliar application was in general more effective; stem application may be more applicable early in the season when its efficacy was higher and when foliar sprays were particularly destructive to beneficial pests. In foliar application, all the systemic neonicotinoids like imidacloprid, clothianidin, admire, thiamethoxam and acetamiprid were found highly toxic to natural enemies in comparison with spirotetramat, buprofezin and fipronil.  相似文献   
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Retention of fetal membranes (RFM) is the major post-partum disorder in dairy cattle. Cyp19 gene encodes the aromatase enzyme responsible for catalyzing the rate limiting step in estrogen biosynthesis, an important hormone for placental maturation and expulsion. The present study was aimed for comparative analysis of Cyp19 gene expression and its epigenetic regulation in placental cotyledons of animals with and without RFM. Significantly lower expression of Cyp19 gene was found in placental samples of RFM affected animals in comparison to normal animals. Methylation analysis of 5 CpG dinucleotides of placenta specific Cyp19 gene promoter I.1 and proximal promoter, PII showed hypo-methylation of both PI.1 and PII in term placenta of normal and diseased animals. In conclusion, a mechanism other than promoter methylation is responsible for decreased aromatase expression in placental cotyledons of animals suffering from RFM.  相似文献   
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