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11.
In the present study efficacy of single intradermal Johnin test, acid fast staining of faecal smear and IS 900 faecal polymerase chain reaction tests was evaluated in 200 goats for detection of Mycobacterium avium subsp paratuberculosis. Two hundred goats comprising 150 goats from an organised farm in Trichur district and 50 goats reared under field condition at farmers premise from Malappuram district of Kerala state formed the study population. Faecal smear from all the 200 goats was stained by Ziehl–Neelsen acid fast stain and faecal polymerase chain reaction (PCR) specific for M. avium subsp paratuberculosis (MAP); IS 900 was performed on all samples. All the animals were subjected to single intradermal Johnin test. Out of 200 goats screened for paratuberculosis, six goats (3%), 11 goats (5.5%) and 42 goats (21%) were found positive by Ziehl–Neelsen acid fast staining of faecal smear, single intradermal Johnin test and IS 900 PCR respectively. Results of the present study indicate that amplification of IS 900 insertion element was the most specific and sensitive diagnostic detection method. Single intradermal Johnin test and Ziehl–Neelsen acid fast staining did not show any significant difference.  相似文献   
12.
ABSTRACT

Sucker production of important clones belonging to different ploidy levels and genomic groups were assessed in three different planting seasons at Kerala Agricultural University, Thrissur, India. The study revealed that morphological characters such as plant height, collar girth, and total number of leaves recorded very strong, significant, and positive correlation with sucker production characters but negative correlation was observed with average leaf production interval and bunch weight. The number of dead suckers was found to be positively correlated with plant height, collar girth, “D” leaf area, bunch weight, and average leaf production interval. In a cluster analysis, six banana varieties that were planted in different three seasons (18 entries) and their pooled data (6 entries) were grouped into four distinct clusters each. In factor/principle component analysis, the first three major factors/principle components amounted to a total of 85.9% of the variability. The communality values of the factor analysis revealed that collar girth was the major relative contributory trait for deciding the sucker yield and production in banana.

Abbreviations: EVS: Early vegetative stage; AVS: Active vegetative stage; FBI: Flower bud initiation; FBD: Flower bud differentiation; PCA: Principle component analysis; FA: Factor analysis  相似文献   
13.
14.
Betanodaviruses are the causative agents of the disease known as viral nervous necrosis (VNN) or viral encephalopathy and retinopathy (VER) in a variety of marine and freshwater fish species. The aim of this study was to demonstrate experimental infection of an isolate of betanodavirus (RGNNV genotype) in freshwater fish, Gambusia affinis, for elucidation of transmission mechanism and potential use as a laboratory model. Morbidity and mortality rate was significantly higher by injection route of infection as compared to immersion by bath and resembled the natural infection of juvenile marine fish. The fish in disease affected group showed severe neurological disorders accompanied by extensive vacuolar degeneration and mild to moderate neuronal necrosis of the brain in comparison to control. Amplification of ~?427 bp product in the variable region of the coat protein gene of betanodavirus was achieved by RT-PCR with 100% sequence homology to RGNNV genotype.  相似文献   
15.
Crop domestication has lead to the selection of a wide range of traits that distinguish domesticated crops from their wild ancestors. Over the past four decades, concerted efforts by archaeologists and geneticists have provided novel insights into the domestication of crops. However, minor crops are rarely a subject for intensive domestication studies and very less is known on the domestication of guar [Cyamopsis tetragonoloba (L.) Taub.] except the trans-domestication hypothesis. The hypothesis proposes that the domestication of guar took place in recent times in the dry areas of the northwestern region of Indo-Pakistan subcontinent and the African wild species, C. senegalensis Guill. et Perr., as its ancestor. However, the process by which the wild species was domesticated is not fully understood. The present paper describes the exploration, collection and in situ characterization of the primitive weedy forms of guar that could be the missing link between the wild and cultivated species. Adak guar is found to grow along with cultivated guar as a weed and is characterized by several primitive characters, prominent among which are spreading habit, small inedible pods which shatter at maturity, hard seed coat and seed dormancy. A total of 66 germplasm collections of these primitive weedy forms of guar have been made from naturally occurring populations in the arid regions of northwestern India. Systematic studies involving these primitive weedy forms can help in understanding the domestication bottlenecks and in utilizing the genetic variation lost during the process of domestication for the improvement of cultivated guar.  相似文献   
16.
Plant growth-promoting bacteria (PGPB) Pseudomonas lurida-NPRp15 and Pseudomonas putida-PGRs4 possessing multiple plant growth-promoting traits were isolated from rhizoplane of pea and rhizosphere of garlic, respectively. The effects of individuals and combinations of Pseudomonas spp. with effective root nodulating symbiotic nitrogen fixing Rhizobium leguminosarum-FB1 on plant growth, nutrient uptake and yield of the rajmash plant were studied under greenhouse conditions. Bacterial inoculation resulted in significantly higher values for plant dry biomass, N, P, K, Zn and Fe contents as compared to the uninoculated control. Furthermore, dual inoculation of P. lurida-NPRp15 with R. leguminosarum-FB1 significantly increased root and shoot dry weight, nodulation, nutrient uptake, pod yield, and nutrient content of pods of rajmash VL63 compared to controls, single and triple inoculation. The results of the study indicate the potential of harnessing the benefit of plant growth-promoting and nitrogen-fixing microorganisms to improve the growth and yield of rajmash.  相似文献   
17.
Genetic Resources and Crop Evolution - The correct article title is provided here, Vulnerability of coffee (Coffea spp.) genetic resources in the United States.  相似文献   
18.
Mice experiencing repeated aggression develop a long-lasting aversion to social contact, which can be normalized by chronic, but not acute, administration of antidepressant. Using viral-mediated, mesolimbic dopamine pathway-specific knockdown of brain-derived neurotrophic factor (BDNF), we showed that BDNF is required for the development of this experience-dependent social aversion. Gene profiling in the nucleus accumbens indicates that local knockdown of BDNF obliterates most of the effects of repeated aggression on gene expression within this circuit, with similar effects being produced by chronic treatment with antidepressant. These results establish an essential role for BDNF in mediating long-term neural and behavioral plasticity in response to aversive social experiences.  相似文献   
19.
Because of the large number of cultivars that require examination in the development of spring wheat (Triticum aestivum L.) cultivars, breeding programs use predictive methods to test end use quality. The Mixograph is a widely used predictive test with which end use quality of many genotypes can be assessed in a short time. By comparison, the Mixolab is a relatively new device with additional capability that might be used for the same purpose. Our objective was to document variability of, and relationships among, 20 parameters obtained from Mixolab, Mixograph, and bake tests. Tests were performed on flour from 18 genotypes grown in 20 environments. Both genotype and environment had significant effects on quality parameter values. Several Mixograph and Mixolab parameters were highly significantly correlated, particularly when genotype mean values over environments were considered. Correlations between loaf volume and Mixolab parameters within environments were inconsistent and suggest that average genotype values over environments will be most useful. For example, the correlation between Mixolab stability and loaf volume (r = 0.25, P < 0.001) was much higher when genotype averages (r = 0.70, P < 0.001) were considered. Our results show that selection for Mixolab stability and water absorption should help delineate and improve the selection of genotypes with greater loaf volume.  相似文献   
20.
Among the 52 species reported in Cucumis, cucumber and muskmelon are the most important species, extensively cultivated by the human for consumption. Diversity has been reported in the wild species of Cucumis from India. Considering the status of genetic erosion of the variability in the various species of Cucumis, a total of 121 germplasm accessions of five different Cucumis species were collected through three explorations in the parts of Aravalli ranges of northwestern India. The paper presents the distribution, collection, extent of variability, associated indigenous traditional knowledge, conservation status of these Cucumis species and prospects of their utilization in crop improvement.  相似文献   
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