Determination of Cadmium in Tap,Sea and Waste Water Samples by Vortex-Assisted Dispersive Liquid-Liquid-Solidified Floating Organic Drop Microextraction and Slotted Quartz Tube FAAS After Complexation with a Imidazole Based Ligand

This study presents a combination of dispersive liquid-liquid-solidified floating organic drop microextraction (DLLSFODM) and slotted quartz tube (SQT) with conventional flame atomic absorption spectrometry (FAAS) to improve the sensitivity for cadmium determination. A ligand namely 2-(4-methylphenyl)-1H-imidazo-[4,5-f]-[1,10]-phenanthroline which has not been used in trace analyte determination was used to form a cadmium complex. Stepwise optimization of parameters affecting complex formation (pH, ligand, and buffer solution) and extraction (extraction and dispersive solvents, salt effect and mixing) was done to maximize cadmium absorbance. The slotted quartz tube was fitted onto the flame burner and optimized to increase residence time of atoms in the flame. Instrumental parameters such as sample and fuel flow rate were also optimized to further enhance the absorbance signal for cadmium. Using optimal parameters and values, the limits of detection and quantification were determined to be 0.81 and 2.69 μg L^?1, respectively. Low percent relative standard deviations (<?6.0%) indicated good precision for both extraction and instrumental measurements. Recovery tests were used to determine the accuracy of the method and the recovery results obtained were between 88 and 113%.

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DIFFERENTIAL RESPONSE OF VIGNA RADIATA L. TO VARIED DOSES OF CHLORPYRIFOS

Twenty-day old seedlings were exposed to different concentrations ranging from 0–1.5 mM of chlorpyrifos through foliar spray in the field condition. The seedlings were uprooted for analyses and observed at the preflowering (five days after treatment, DAT), flowering (10 DAT) and post-flowering (20 DAT) stages for various morphological parameters such as plant height, number of branches, leaves per plant, total leaf area, plant biomass and photosynthetic pigments viz. Chlorophyll (Chl) a, Chl b, Total Chl, and Carotenoid (Car) content. Yield attributing characters like number of pods plant^?1, number of seeds pod^?1 and weight of 100 seeds were analyzed from both control and treated plant after harvest stage. All the growth parameters, pigments’ activity and yield parameters increased at 0.3 mM insecticidal treatment, when compared with control. Further increases in insecticide level had a negative impact upon all studied parameters.     

Pathogenicity of four native isolates of entomopathogenic nematodes against Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae)

Journal of Plant Diseases and Protection - The confused flour beetle, Tribolium confusum Jacquelin du Val, 1863 (Coleoptera: Tenebrionidae) is a major pest on stored grains. Chemical pesticides are...     

Accumulative effects of humic acid and multinutrient foliar fertilizers on the vegetative and reproductive attributes of citrus (Citrus reticulata cv. kinnow mandarin)

Abstract

Field trials were performed to investigate the effects of humic acid (HA) and multinutrient foliar fertilizer “Micro Power” (MP) coupled with farmer’s practices ( FP ), addressed in single and/or split dose frames at different plant phenological stages on various vegetative, reproductive, and physiological attributes of citrus trees (Citrus reticulata cv. kinnow mandarin). The results exhibited a profound response of treatments on various growth parameters (32.5% increase in plant height, 22.2% increase in fruit set branch^?1, 5.25% decrease in fruit drop percentage, 89.81% increase in fruit yield (kg), etc.) of citrus trees when compared to the control (FP). Likewise, a significant positive response was observed regarding various plant physiological parameters (leaf nutrients, total chlorophyll content, etc.) and physicochemical characteristics (ascorbic acid, total sugars, etc.) of citrus fruits. This study confirmed the reproducibility of HA and MP applications to improve the yield/quality of citrus and can lead to an organically sustainable citriculture.     

Influence of phosphorus on nitrogen fixation in chickpea cultivars

Phosphorus (P) is a major nutrient factor influencing nitrogen (N) accumulation and partitioning of photosynthates in plants, especially the symbiotic N₂‐fixation in legumes. This study was conducted to investigate how P application (0, 20, 40, and 60 kg P₂O₅/ha) affects symbiotic N₂‐fixation of three cultivars (C 235, Pusa 408, and Pusa 417) of chickpea (Cicer arietinum L.). Application of P in general significantly increased leaf area, shoot dry weight, and the rate of acetylene (C₂H₂) reduction. Phosphorus concentration of shoots and roots, soluble sugar content of nodules, and shoot N accumulation were also significantly increased, especially by P at the 40 kg P₂O₅/ha rate. The P concentration in nodules was, however, not affected by different levels of P. The Pusa 417 cultivar responded better than the others to the P treatments. Phosphorus‐deficient plants accumulated sugar in their leaves. The interaction effect was found significant on leaf area, shoot dry weight, nodule number, and shoot N accumulation. Pusa 417 gave greatest response to 40 kg P₂O₅/ha but Pusa 408 and C 235 interacted best with the 20 kg P₂O₅/ha rate only. The increased nodulation and symbiotic N₂‐fixation on P application seem to be the result of morphologically advanced shoots which are making more photosynthates for transport to nodules and not the direct effect of P on the nodules.     

Immunodetection of coproantigens for the diagnosis of amphistomosis in naturally infected Indian Water Buffalo,Bubalus bubalis

The infection of gastrointestinal helminths in livestock is routinely diagnosed by microscopical examination of faecal samples for the presence of ova/eggs but this approach becomes ineffective for the seasonally egg producing trematodes. Therefore, an alternative approach to detect the coproantigens of liver and rumen amphistomes, Gigantocotyle explanatum and Gastrothylax crumenifer respectively, infecting Indian water buffalo Bubalus bubalis, was undertaken using ELISA, immunodot and countercurrent immunoelectrophoresis (CCIEP). The hyperimmune polyclonal antisera were separately raised in rabbits against excretory/secretory (ES) antigens of both the flukes under study. An overall 70% buffalo faecal samples were tested positive for G. crumenifer and 75% for G. explanatum in Aligarh region. The ELISA results reflected higher infection intensity among individual buffaloes that was also observed at necropsy. Using the respective homologous hyperimmune antiserum, 55% buffaloes tested positive for G. crumenifer and 65% positive for G. explanatum in immunodot assay. Further, the faecal samples with high absorbance values in ELISA and strong immunodot reaction tested positive in CCIEP. The analysis of CCIEP result revealed two and one precipitin bands in G. crumenifer and G. explanatum respectively, indicating prominent antigenic differences in the coproantigens of these two parasites. Taken together, it is suggested that polyclonal antibodies could be conveniently used for the detection of coproantigens by ELISA and immunodot methods, particularly during the non-egg producing phase of the seasonally regulated reproductive cycle of the rumen amphistome G. crumenifer. It is concluded that the coproantigen detection is a good alternative over conventional method for the diagnosis of amphistomosis in livestock; however, further studies are required on a larger sample size of field buffaloes to augment the reproducibility of the present results.     

Dietary histidine requirement of Singhi,Heteropneustes fossilis fry (Bloch)

Amino acids are vital for all living organisms including fish and histidine is an essential amino acid for fish. In view of this, dietary histidine requirement of fry Heteropneustes fossilis was determined by feeding casein–gelatin‐based isonitrogenous (430 g kg^?1 CP) and isocaloric (17.9 MJ kg^?1 GE; 15.5 MJ kg^?1 DE) amino acid test diets (10 to 20 g histidine kg^?1 dry diet) to quadruplicate groups of randomly assigned fish to apparent satiety for 12 weeks. Maximum absolute weight gain (AWG; 44 g fish^?1), protein retention efficiency (PRE; 20%), protein efficiency ratio (PER; 1.04), haemoglobin (Hb; 11.24 g dL^?1), haematocrit (Hct; 35.11%), red blood count (RBCs; 2.98 × 10⁹ mL^?1) and lowest erythrocyte sedimentation rate (ESR; 1.92 mm h^?1) were obtained at 16 g histidine kg^?1 dry diet. The 95% maximum quadratic response of above data exhibited the requirement to be at 15.2, 15.1, 15.6 and 15.5 g histidine kg^?1 diet. As histidine is found in higher concentration in haemoglobin, requirement obtained for Hct% and Hb is 4% greater than that required for maximizing weight gain and protein retention. Based on these results, dietary histidine requirement of H. fossilis fry is recommended between 15.1 and 15.6 g kg^?1, corresponding to 35.1–36.3 g kg^?1 protein.     

Matrix metalloproteinase expression in sheep with listerial meningoencephalitis

Matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of several central nervous system (CNS) diseases. In this study, we investigated the presence of Listeria monocytogenes antigens and detected the expression of MMP-9 and MMP-7 in the brains of 22 sheep with clinical signs and histopathological findings characteristic of listerial meningoencephalitis. Archived sections from the brainstem, cerebrum, and cerebellum were stained for immunohistochemistry. L. monocytogenes antigens were located mainly in the cytoplasm of neutrophils and some macrophages and/or extracellularly within microabscesses of the brainstem. MMP-9 was mainly immunolocalised in the endothelial cells, microglial cells, and neurons especially in inflammatory areas. MMP-7 immunoreactivity was detected in perivascular cuffs, microglial cells, and only a few neurons. Overall, immunohistochemistry in formalin-fixed, paraffin-embedded tissues is a useful tool for the diagnosis of encephalitic listeriosis caused by L. monocytogenes, and MMP-9 and MMP-7 may contribute to the pathogenesis of listerial meningoencephalitis.