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171.
Neutrophils employ both oxidative and non oxidative mechanisms to destroy pathogens. Function of neutrophils coming in milk during mammary invasion is not clearly understood in dairy animals. Therefore, the present study was designed in 36 Sahiwal cows to see the changes occurring in the neutrophil activity of cows suffering from subclinical (SCM) and clinical mastitis (CM). Cows were divided into three groups as healthy (n?=?12), SCM (n?=?12) and CM (n?=?12) groups on the basis of CMT scoring, gross morphological changes in milk, bacteriological examination of milk and by counting milk SCC. Significantly (P?P?P?Toll like receptors 2 and 4 in blood and milk neutrophils were found to be significantly (P?P?TLR4 with the formation of NETs and change in surface architecture. Formation of NET like structures seemed to be an effective mode of defense employed by neutrophils of cows suffering from clinical mastitis.  相似文献   
172.
Theeffect of pig dung, as pond manure [at 18 and 36 tha–1 yr–1] and as fish feed ingredient[replacing traditional diet composed of solvent extracted rice bran and mustardcake (1:1) at 25, 50, 75 and 100% levels], was observed on water quality, pondproductivity and survival and growth of carp in polyculture system during winter(12–18 °C) and summer (18–36 °C)months. The studies on water quality parameters viz pH, dissolved oxygen andalkalinity revealed that pig dung even at higher levels (both as manure and /oras feed ingredient) did not deteriorate the quality of water, as all the waterparameters remained within the optimum ranges required for carps. The nutrient(phosphates and nitrates) status of water was significantly better in pondsreceiving pig dung as pond manure at 36 tha–1 yr–1. Pond productivity in terms ofplankton production (phyto and zooplankton) was also significantly higher innutrient rich water (36 tha–1 yr–1) both during winter andsummer. Further, in all the ponds (including control) phytoplankton levels weresignificantly higher during winter and zooplankton was higher during summer. Thestudies revealed 100% survival of all the fish species in all the treatments.During winter, the growth of carp was higher in treatments where pig dung wasused as feed ingredient (at 25% level), whereas during summer growth was higherwhere pig dung was used either as pond manure and/or as feed ingredient (athigher levels). Further, among carps, the growth of Indian major carps vizCatla catla, Labeo rohita and Cirrhinamrigala was higher during summer and that of exotic carps vizCyprinus carpio and Ctenophayrengodonidella was higher during winter.  相似文献   
173.
Mikania micrantha, a creeper and climber, has invaded forests and agricultural areas in the Western Ghats. A quantification of the effect of Mikania on species richness and factors that contribute to its success would help to understand the invasion success of Mikania in the Western Ghats of India. This study investigated its impact on species richness and factors that contribute to its invasion success. Impact of Mikania on species richness was studied in areas invaded by Mikania and not yet invaded by Mikania by quadrat (1 × 1 m2) method. Growth experiments were carried out with Mikania rhizosphere soil and soil treated with Mikania leaf leachate. Chemical characteristics such as electrical conductivity, organic matter, extractable P, total organic N and water-soluble phenolics, and microbial respiration of soil invaded by Mikania and not yet invaded by Mikania were measured. We observed lower species richness in areas invaded by Mikania compared to areas not yet invaded by Mikania. Seedling growth was suppressed in Mikania rhizosphere soil or soil treated with higher levels of Mikania leaf leachate. Higher levels of organic matter, total organic N and water-soluble phenolics, and lower microbial activity were observed in Mikania rhizosphere soil. Soil treated with Mikania leaf leachate has higher amounts of water-soluble phenolics. Mikania invasion appears to reduce plant species richness in the Western Ghats, and discourage seedling growth of certain plant species. Factors that are likely to contribute to Mikania success are its ability to pre-empt light and alter soil chemistry and biochemistry in ways that benefit the species.  相似文献   
174.
Wild melon diversity in India (Punjab State)   总被引:1,自引:1,他引:0  
We present here the first comprehensive genetic characterization of wild melon accessions from northern India. The genetic diversity among 43 wild melon accessions collected from the six agro-ecological regions of the Punjab State of India was assessed by measuring variation at 16 Simple Sequence Repeat (SSR) loci, morphological traits of plant habit and fruit morphological traits, two yield-associated traits, root nematode resistance and biochemical composition (ascorbic acid, carotenoids, titrable acidity). Variation among accessions was observed in plant habit and fruit traits and wild melon germplasm with high acidity and elevated carotenoid content and possessing resistance to Meloidogyne incognita was identified in the collection. A high level of genetic variability in wild melon germplasm was suggested by SSR analysis. Comparative analysis using SSRs of the genetic variability between wild melons from the north and other melons from the south and east regions of India and also reference accessions of cultivated melon from Spain, Japan, Korea, Maldives, Iraq and Israel, showed regional differentiation among Indian melon accessions and that Indian germplasm was not closely related to melon accessions from other parts of the world. A highly drought tolerant accession belonging to var. agrestis Naud. was also identified.  相似文献   
175.
Rhizoctonia solani causing rice sheath blight is responsible for significant crop yield losses. Trichoderma spp., biological control agents, have been reported to antagonize R. solani through coordinated action of several cell wall-degrading enzymes including endochitinase and β-1,3-glucanase. In this study two antifungal genes, encoding endochitinase and β-1,3-glucanase, isolated from Trichoderma sp. antagonistic to R. solani, were cloned individually in His-tagged expression vectors and mobilized in Escherichia coli for protein expression. The purified proteins assayed in vitro with R. solani impeded pathogen growth independently by causing hyphal distortions revealed through scanning electron microscopy. The combined use of endochitinase and β-1,3-glucanase did not enhance the inhibition. The distortions caused by endochitinase were due to catalytic activity of Glu172 and Asp241 residues on glycosidic linkages in chitin polymers, whereas Glu628, Tyr631, and Asp569 in β-1,3-glucanase targeted glucan polymers. The distinctions of this study from earlier reports are (a) chitin polymers in the R. solani cell wall are exposed and not embedded within the β-glucan matrix; (b) chitin and β-1,3-glucan are vital polymers in the R. solani cell wall, rather than chitin as the only main polymer; and (c) hyphal tips of R. solani remain unaffected after an antifungal assay with endochitinase and β-1,3-glucanase, instead of exhibiting distortion.  相似文献   
176.

Stem rot, incited by Sclerotinia trifoliorum Eriksson is one of the most devastating soil borne fungal pathogens of berseem (Trifolium alexandrinum L.) inflicting significant fodder and seed yield losses. Eleven plant extracts, six organic inputs, one elicitor and five organic and inorganic salts were assayed for their effectiveness against S. trifoliorum under in vitro conditions. Extracts of Aegle marmelos and Cymbopogan citrates showed complete mycelial inhibition of S. trifoliorum at 5% concentration. Among organic inputs, panchgavya and fermented cow urine recorded 100% inhibition to mycelial growth of stem rot pathogen at 10% concentration. Elicitor (chitosan) and salts namely copper sulphate and potassium carbonate provided complete mycelial inhibition of test pathogen under in vitro conditions at 0.1, 2.0 and 5.0% concentrations, respectively. The plant extracts, organic inputs and salts that exhibited highest mycelial inhibition to S. trifoliorum under in vitro conditions were evaluated for their antifungal efficacy under greenhouse and field experiments during rabi 2017–18 and 2018–19. The extracts of chitosan (78.58; 77.15%), panchgavya (75.99; 67.14%), copper sulphate 71.38; 61.18%) and A. marmelos (71.75; 56.24%) have recorded highest percent disease control as compared to untreated control in greenhouse and field trials in rabi 2017–18 and 2018–19, respectively. Significant increase in green fodder yield of berseem from 9.87 to 33.38% was also recorded after treatment with plant extracts, organic inputs and some salts. The current study showed that plant extracts, organic inputs and salts have potential for the management of stem rot of berseem.

  相似文献   
177.
Pathogenic and putatively nonpathogenic isolates of Fusarium oxysporum are ubiquitously present in soils. Pathogenic isolates designated as formae speciales are very host specific. The genes that determine host-specific pathogenicity may be expected to be similar between strains within a forma specialis. Three different pathways were used for mining putative effectors from 85 assembled genome sequences representing isolates from the agricultural and natural ecosystems. A total of 436 putative effectors were identified, of which 115 were present in all the isolates. The presence–absence phylogeny showed some clustering of isolates based on the ecosystems, while some clustered with isolates from different ecosystems. Isolates from the agricultural and natural ecosystems shared 358 putative effectors. Agricultural isolates had 78 unique putative effectors, while isolates from the natural ecosystems had no unique effectors. Isolates from the natural ecosystems had effectors that have previously been confirmed with virulence functions in other filamentous fungi, suggesting that the natural ecosystems may be acting as a reservoir for pathogenic isolates awaiting compatible hosts. They also possessed putative effectors with domains involved in polysaccharide degradation. The putative effectors in the natural ecosystem isolates may be important for both parasitic and ecological fitness. Further analysis of the three characterized ff. sp.—lycopersici, niveum, and pisi—revealed high conservation in the pathogenicity mechanism in F. oxysporum. However, each strain had unique putative effectors, which may be responsible for host specificity.  相似文献   
178.
The inherent properties of rayon fibre have been changed with additional properties through graft copolymerization of acrylamide, AAm, by chemical method using ceric ammonium nitrate/nitric acid, (CAN/HNO3), as a redox initiator and γ-radiation induced mutual method. Reaction conditions such as monomer and initiator concentration, liquor ratio, temperature and time of reaction, amount of radiation dose have been optimized with respect to percentage of grafting. Maximum percentage of grafting (Pg), (40 %) using CAN/HNO3 was obtained at [CAN]=31.92×10?3 moles/l, [HNO3]=79.36×10?2 moles/l, [AAm]=14.07×102 moles/l in 20 ml of H2O at 45 °C within 120 min while in case of radiation induced method, maximum Pg (30 %) was obtained at higher monomer concentration (28.14×10?2 moles/l) and time (180 min) in 10 ml of H2O at room temperature with total dose exposure of 11.178 kGy. The graft copolymers were characterized by FTIR, thermogravimetric and scanning electron micrographic analysis. Swelling behaviour in water, methanol, ethanol, acetone and DMF and dyeing and flame retarding properties of rayon fibre and grafted rayon fibre were investigated. Percent dye uptake (71.8 %) was found to be higher than that observed for the pristine fibre (57.4 %) and the grafted fibre after post phosphorylation reaction showed excellent flame retarding properties.  相似文献   
179.
Yellow mosaic disease (YMD) is one of the major diseases affecting mungbean (Vigna radiata (L.) Wilczek). In this study, we report the mapping of the quantitative trait locus (QTL) for mungbean yellow mosaic India virus (MYMIV) resistance in mungbean. An F8 recombinant inbred line (RIL) mapping population was generated in Thailand from a cross between NM10-12-1 (MYMIV resistance) and KPS2 (MYMIV susceptible). One hundred and twenty-two RILs and their parents were evaluated for MYMIV resistance in infested fields in India and Pakistan. A genetic linkage map was developed for the RIL population using simple sequence repeat (SSR) markers. Composite interval mapping identified five QTLs for MYMIV resistance: three QTLs for India (qYMIV1, qYMIV2 and qYMIV3) and two QTLs for Pakistan (qYMIV4 and qYMIV5). qYMIV1, qYMIV2, qYMIV3, qYMIV4 and qYMIV5 explained 9.33%, 10.61%, 12.55%, 21.93% and 6.24% of variation in disease responses, respectively. qYMIV1 and qYMIV4 appeared to be the same locus and were common to a major QTL for MYMIV resistance in India identified previously using a different resistant mungbean.  相似文献   
180.
(1) Total and free gossypol contents were 6.2 and 0.8, 5.4 and 0.5, and 6.1 and 0.7 g/kg in meals processed (solvent extracted) from Bollgard (BG) II, non-BG II or commercial cottonseeds, respectively. (2) Broiler chicks were given one of 7 dietary treatments (iso-nitrogenous, 220 and 195 g crude protein/ kg diet at 0 to 21 and 21 to 42 d, respectively, at a metabolisable energy concentration of 12.15 MJ/kg). The treatments were: D1 (control, soybean meal [SBM] based), D2 and D3 (commercial CSM at 100 g/kg of diet with and without additional iron), D4 and D5 (BG II CSM with and without additional iron), and D6 and D7 (non-BG II parental CSM with or without additional iron). (3) Body weight gain, feed intake, feed conversion efficiency, nutrient utilisation, certain blood constituents and carcase traits were not significantly affected by dietary treatments. (4) Weights of bursa and thymus were significantly higher in groups given diets containing BG II or non-BG diets containing added iron. (5) The results suggest that low free gossypol content cottonseed meals, for example, BG II, non-BG II and commercial solvent-extracted CSM could be included at 100 g/kg in broiler diets, safely replacing soybean meal without additional iron.  相似文献   
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