Studies on Nodulation, Biochemical Analysis and Protein Profiles of Rhizobium Isolated From Indigofera species

Nodulation characteristics in five species of Indigofera viz., I .trita, I. linnaei, I. astragalina, I. parviflora and I. viscosa was studied at regular intervals on the plants raised in garden soil. Among the species studied, highest average number of nodules per plant of 23 with maximum sized nodules of 8.0 mm diameter was observed in I. astragalina. Biochemical analysis of root nodules of I. astragalina revealed that the leghaemoglobin content of nodules and nitrogen content of root, shoot, leaves and nodules were gradually increased up to 60 DAS, and then decreased with increase in age. Rhizobium isolates of five species of Indigofera were isolated and screened for enzymatic activities and total cellular protein profiles. All the five isolates showed nitrate reductase, citrase, tryptophanase and catalase activity while much variation was observed for enzymes like gelatinase, urease, caseinase, lipase, amylase, lysine decarboxylase and protease activities. Among the isolates studied, only the isolate from I. viscosa has the ability to solubilize the insoluble tricalcium phosphate. All the Rhizobium isolates exhibit similarity in protein content, except the isolate from I. viscosa which showed one additional protein band

Parametric optimization MRR and surface roughness in wire electro discharge machining (WEDM) of D2 steel using Taguchi based utility approach

Abstract: This paper reports the effect of process parameters on material removal rate (MRR) and surface roughness (Ra) in wire electro discharge machining of AISI D2 steel. The experiments were performed by different cutting conditions of pulse on time (Ton), pulse off time (Toff), servo voltage (SV) and wire feed (WF) by keeping workpiece thickness constant. Taguchi L27 orthogonal array of experimental design is employed to conduct the experiments. Multi-objective optimization was performed using Taguchi based utility approach to optimize MRR and Ra. Analysis of means and variance on to signal to noise ratio was performed for determining the optimal parameters. It reveals that the combination of Ton3, Toff1, SV1, WF2 parameter levels is beneficial for maximizing the MRR and minimizing the Ra simultaneously. The results indicated that the pulse on time is the most significant parameter affects the MRR and Ra. The melted droplets, solidified debris around the craters, cracks, and blow holes were observed on the machined surface for a higher pulse on time and lower servo voltage. Recast layer thickness increased from an increase in pulse on time duration. The machined surface hardness of D2 steel is increased due to the repetitive quenching effect and formation oxides on the machined surface

Studies on interaction of nematode, Pratylenchus delattrei and fungal pathogen, Fusarium incarnatum associated with crossandra wilt in Tamil Nadu, India

ABSTRACT Investigations were under taken in pot culture experiment to assess a possible interaction between fungal pathogen of crossandra, Fusarium incarnatum and lesion nematode Pratylenchus delattrei, at various population density combinations, time of inoculation and their effect on plant growth and wilt incidence of crossandra. Among varies pathogen and nematode population densities tested, the inoculation of pathogen load @3% w/v and nematode @ 1/g soil resulted in maximum reduction of plant growth parameters viz., shoot length (49.8%), shoot dry weight (52.6%), root length (47.0%), root dry weight (47.4%), and flower yield (82.6%). More over maximum root lesion index of 3.9/1-5 scale, wilt disease incidence of (50%) and nematode population up to 365 per 200 cc soil, were also recorded. Other experimental results revealed that the treatment involving inoculation of nematode prior to fungal pathogen recorded more disease incidence (58.3%), nematode (381/200cc) and pathogen (12.1×10 3 ), populations and there was significant reduction in root length, root weight, shoot height and shoot weight when compared with inoculation of pathogen and nematode simultaneously or inoculation of pathogen prior to nematode

Temporal variation in the specific growth rate of bacterioplankton in the River Cauvery and its four down stream tributaries in Karnataka State, India

The temporal variation in the Specific Growth Rate (SGR) of natural population of heterotrophic bacterioplankton of the river Cauvery and its four down stream tributaries in Karnataka State was monitored over a period of two years from February 2000 to January 2002. The SGR was calculated by taking into account only the abundance of bacterioplankton at the beginning (0 h) and at the end (48 h) incubation period, at room or river temperature. The mean SGR was less and significantly different in the surface waters of river Kapila, Shimsha, Suvarnavathy and Arkavathy. But it was more and significantly different in river Cauvery when compared to other tributaries. This suggests that the river Cauvery was more favorable habitat for SGR of bacterioplankton than the other four watercourses studied. Investigation of interrelationship between SGR and other bacterial variables showed presence of only one correlation with direct counts of particle bound bacteria in river Arkavathy. Further, the relationship between SGR of bacterioplankton and other environmental variables showed the presence of six correlations in river Shimsha, five in river Suvarnavathy, three in river Cauvery, and two each in river Kapila and river Arkavathy. Negative SGR were recorded on thirteen occasions in river Cauvery followed by eleven in river Shimsha, nine in river Suvarnavathy, seven in river Arkavathy and five in river Kapila, out of fifty SGR determinations. This negative SGR were a result of decrease in the observed bacterial cell counts after 48 h incubation from that of 0 h count. The probable reason for such negative growth rate and dependency of SGR of bacterioplankton and environmental variables has been discussed

Tool Wear Rate and Surface Integrity Studies in Wire Electric Discharge Machining of NiTiNOL Shape Memory Alloy Using Diffusion Annealed Coated Electrode Materials

Electrode material used in wire electric discharge machining (WEDM/wire EDM) plays a vital role in determining the machined component quality. In particular, when machining hard materials like nickel titanium/NiTi (NiTiNOL) shape memory alloy, the quality of electrode material is important as it may have adverse effects on the surface properties of the alloy. Different electrode materials give different performances, as each electrode material is made up of different conductivity, compositions and tensile strength. Therefore, detailed experimental studies have been carried out to understand the effect of diffusion annealed coated wires (X-type and A-type) on NiTiNOL SMA during the wire EDM process. The tool wear rate and surface roughness responses have been studied for both the electrode materials against different wire EDM variables such as pulse time, pause time, wire feed and spark gap set voltage. The impact of these process parameters on the stated output responses has been analyzed and further surface and subsurface analysis of the machined component has been carried out to understand the impact of diffusion annealed electrode materials during the wire EDM process. The investigation reveals that an A-type diffusion annealed coated wire is found to be most suitable in terms of tool wear rate, surface roughness and surface integrity during machining of NiTiNOL shape memory alloy compared to X-type and traditional brass-based electrode materials. Surface topographical properties were studied using confocal microscopic analysis and scanning electron microscope (SEM) with energy-dispersive spectroscopy (EDS) analysis. The subsurface analysis like microhardness and recast layer thickness was also studied for both the wires against different machining conditions

Not Available

Not AvailableThere was no report on an index leaf in oil palm (Elaeis guineensis Jacq.) for biochemical analysis, grown under irrigated condition. In oil palm growing countries, frond (leaf) no. 17 was used as an index leaf for different analysis including biochemical analysis. In India, oil palm is being grown as irrigated crop and hence, it is necessary to select an index leaf/ leaves, which can be sampled for analyzing different biochemical constituents as well as leaf nutrients. Some of the biochemical constituents (chlorophylls, carotenoids, total carbohydrates and soluble protein) and nitrogen content in different leaves of oil palm were analysed for the selection of index leaf. It was observed that chlorophyll-a, chlorophyll-b, total chlorophyll and carotenoids were highest in frond no. 25. Total carbohydrate and soluble protein were highest in frond no 20, where as nitrogen was found highest in frond no. 9. For all these parameters, several other fronds were also on par with the highest value. For the analysis of pigments, mature leaves (beyond frond no. 6) were found suitable. More mature fronds (19th-25th) showed higher protein and carbohydrate content. For the analysis of nitrogen and biochemical parameters (like pigments, soluble protein and total carbohydrate) from single sampling, 9th frond was found to be most suitable, as it showed the value on par with highest values in all the cases. Hence, 9th leaf could be suggested as an index leaf.Not Availabl