Efficacy of different fungicides for management of early blight disease of potato

The early blight of potato may be controlled by using bio-control agents and plant extracts but not effectively and rapidly. But using of chemical fungicides the disease can be controlled easily and losses of yield will be reduced compare to above mentioned both control measures. Keeping this in mind an experiment was conducted to test the efficacy of seven different fungicides (difenoconazole, propiconazole, hexaconazole, propineb 61% + iprov-alicarb 5.25%, propineb, carbendazim and metalaxyl 8% + mancozeb 64%) for controlling early blight of potato un-der in vivo as well as in vitro condition. These antifungal compounds were applied 3 times at 7days interval after first appearance of the disease in the field. Highest percent disease reduction (57.88%) and highest yield of tuber (27.03 t/ha) was recorded in plot sprayed with propiconazole @1 ml/lit followed by propineb and propineb 61% + iprovalicarb 5.25%, with percent disease reduction 55.98%, 51.90% and yield 26.30 t/ha and 24.53 t/ha respectively. Simultaneously in vitro efficacy of these fungicides were also tested against Alternaria solani where propiconazole and propineb exhibited highest percent inhibition(100%) in radial growth and in case of spore germination inhibition in spite of these two fungicides difenoconazole, hexaconazole and propineb 61% + iprovalicarb 5.25% exhibit same result i.e. 100% inhibition compared to control as well as other treatments. Therefore it may be suggested that propiconazole and propineb can be used successfully in controlling of this disease

INFERENCE ON P(X < Y ) FOR EXPONENTIATED FAMILY OF DISTRIBUTIONS

Inference on R = P(X &lt; Y ) has been considered when X and Y belong to independent exponentiated family of distributions. Maximum Likelihood Estimator (MLE), Uniformly Minimum Variance Unbiased Estimator (UMVUE) and Bayes Estimator of R has been derived and compared through simulation study. Exact and approximate confidence intervals and Bayesian credible intervals have also been derived

Management of early blight of potato using bio control agents and plant extracts

The early blight of potato is mainly controlled by using chemical fungicides but chemical fungicides have got some adverse effect on environment as well as human beings. Keeping this in mind an experiment was conducted to test the efficacy of four plant extracts (tea, garlic, onion and neem leaf extract) and four bio-control agents (Trichoderma viride, Pseudomonas fluorescence, Streptomyces graseoviridis and Bacillus substilis) in controlling early blight of potato under field and in in vitro condition. These antifungal compounds were applied 3 times at 7days interval after first appearance of the disease in the field. Among the bio control agents T. viride was found highly effective in per cent disease reduction (52.39%) of disease over control treatment. The tuber yield (25.51 t/ ha.) was also highest in this treatment compared to control treatment (19.53 t/ha). This was followed by treatment T2 i.e. P. fluorescens where per cent incidence and intensity of disease were (65.00%) and (19.10%) respectively with 38.97% reduction of disease over control with tuber yield 23.65 t/ha. It was followed by S. graseoviridis where per cent incidence and intensity of disease were (68.00%) and (22.90%) respectively with 26.30% reduction of disease over control with tuber yield 21.07 t/ha. Among plant extracts, only neem leaf extract exhibited per cent reduction of disease (33.18%) over control treatment in field condition and inhibition of radial growth (59.85%) and spore germination (81.95%) in in vitro condition. Therefore both T. viride and neem can be used for managing the early blight of potato

Nonlocal elasticity based magnetic field affected vibration response of double single-walled carbon nanotube systems

peer-reviewedThe behaviour of carbon nanotubes in a magnetic field has attracted considerable attention in the scientific community. This paper reports the effects of a longitudinal magnetic field on the vibration of a magnetically sensitive double single-walled carbon nanotube system (DSWNTS). The two nanotubes of the DSWNTS are coupled by an elastic medium. The dynamical equations of the DSWNTS are derived using nonlocal elasticity theory. The two nanotubes are defined as an equivalent nonlocal double-Euler-Bernoulli beam system. Governing equations for nonlocal bending-vibration of the DSWNTS under a longitudinal magnetic field are derived considering the Lorentz magnetic force obtained from Maxwell's relation. An analytical method is proposed to obtain nonlocal natural frequencies of the DSWNTS. The influence of (i) nanoscale effects and (ii) strength of longitudinal magnetic field on the synchronous and asynchronous vibration phase of the DSWNTS is examined. Nonlocal effects with and without the effect of magnetic field are illustrated. Results reveal the difference (quantitatively) by which the longitudinal magnetic field affects the nonlocal frequency in the synchronous and asynchronous vibration modes of a DSWNTS. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4720084]PUBLISHEDpeer-reviewe

Marked modulation by phosphate of phosphoenolpyruvate carboxylase in leaves of Amaranthus hypochondriacus, a NAD-ME type C<SUB>4</SUB> plant: decrease in malate sensitivity but no change in the phosphorylation status

The effect of Pi on the properties of phosphoenolpyruvate carboxylase (PEPC) from Amaranthus hypochondriacus, a NAD-ME type C4 plant, was studied in leaf extracts as well as with purified protein. Efforts were also made to modulate the Pi status of the leaf by feeding leaves with either Pi or mannose. Inclusion of 30 mM Pi during the assay enhanced the enzyme activity in leaf extracts or of purified protein by &gt;2-fold. The effect of Pi on the enzyme purified from dark-adapted leaves was more pronounced than that from light-adapted ones. The Ki for malate increased &gt;2.3-fold and &gt;1.9-fold by Pi in the enzyme purified from dark-adapted leaves and light-adapted leaves, respectively. Pi also induced an almost 50-60% increase in Km for PEP or Ka for glucose-6-phosphate. Feeding the leaves with Pi also increased the activity of PEPC in leaf extracts, while decreasing the malate sensitivity of the enzyme. On the other hand, Pi sequestering by mannose marginally decreased the activity, while markedly suppressing the light activation, of PEPC. There was no change in phosphorylation of PEPC in leaves of A. hypochondriacus due to the feeding of 30 mM Pi. However, feeding with mannose decreased the light-enhanced phosphorylation of PEPC. The marked decrease in malate sensitivity of PEPC with no change in phosphorylation state indicates that the changes induced by Pi are independent of the phosphorylation of PEPC. It is suggested here that Pi is an important factor in regulating PEPC in vivo and could also be used as a tool to analyse the properties of PEPC

Dramatic difference in the responses of phosphoenolpyruvate carboxylase to temperature in leaves of C<SUB>3</SUB> and C<SUB>4</SUB> plants

Temperature caused phenomenal modulation of phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) in leaf discs of Amaranthus hypochondriacus (NAD-ME type C4 species), compared to the pattern in Pisum sativum (a C3 plant). The optimal incubation temperature for PEPC in A. hypochondriacus (C4) was 45&#176;C compared to 30&#176;C in P. sativum (C3). A. hypochondriacus (C4) lost nearly 70% of PEPC activity on exposure to a low temperature of 15&#176;C, compared to only about a 35% loss in the case of P. sativum (C3). Thus, the C4 enzyme was less sensitive to supra- optimal temperature and more sensitive to sub- optimal temperature than that of the C3 species. As the temperature was raised from 15&#176;C to 50&#176;C, there was a sharp decrease in malate sensitivity of PEPC. The extent of such a decrease in C4 plants (45%) was more than that in C3 species (30%). The maintenance of high enzyme activity at warm temperatures, together with a sharp decrease in the malate sensitivity of PEPC was also noticed in other C4 plants. The temperature-induced changes in PEPC of both A. hypochondriacus (C4) and P. sativum (C3) were reversible to a large extent. There was no difference in the extent of phosphorylation of PEPC in leaves of A. hypochondriacus on exposure to varying temperatures, unlike the marked increase in the phosphorylation of enzyme on illumination of the leaves. These results demonstrate that (i) there are marked differences in the temperature sensitivity of PEPC in C3 and C4 plants, (ii) the temperature induced changes are reversible, and (iii) these changes are not related to the phosphorylation state of the enzyme. The inclusion of PEG-6000, during the assay, dampened the modulation by temperature of malate sensitivity of PEPC in A. hypochondriacus. It is suggested that the variation in temperature may cause significant conformational changes in C4-PEPC

Calcium-stores mediate adaptation in axon terminals of Olfactory Receptor Neurons in Drosophila

<p>Abstract</p> <p>Background</p> <p>In vertebrates and invertebrates, sensory neurons adapt to variable ambient conditions, such as the duration or repetition of a stimulus, a physiological mechanism considered as a simple form of non-associative learning and neuronal plasticity. Although various signaling pathways, as cAMP, cGMP, and the inositol 1,4,5-triphosphate receptor (InsP₃R) play a role in adaptation, their precise mechanisms of action at the cellular level remain incompletely understood. Recently, in <it>Drosophila</it>, we reported that odor-induced Ca²⁺-response in axon terminals of olfactory receptor neurons (ORNs) is related to odor duration. In particular, a relatively long odor stimulus (such as 5 s) triggers the induction of a second component involving intracellular Ca²⁺-stores.</p> <p>Results</p> <p>We used a recently developed <it>in-vivo </it>bioluminescence imaging approach to quantify the odor-induced Ca²⁺-activity in the axon terminals of ORNs. Using either a genetic approach to target specific RNAs, or a pharmacological approach, we show that the second component, relying on the intracellular Ca²⁺-stores, is responsible for the adaptation to repetitive stimuli. In the antennal lobes (a region analogous to the vertebrate olfactory bulb) ORNs make synaptic contacts with second-order neurons, the projection neurons (PNs). These synapses are modulated by GABA, through either GABAergic local interneurons (LNs) and/or some GABAergic PNs. Application of GABAergic receptor antagonists, both GABA_Aor GABA_B, abolishes the adaptation, while RNAi targeting the GABAB_R(a metabotropic receptor) within the ORNs, blocks the Ca²⁺-store dependent component, and consequently disrupts the adaptation. These results indicate that GABA exerts a feedback control. Finally, at the behavioral level, using an olfactory test, genetically impairing the GABA_BR or its signaling pathway specifically in the ORNs disrupts olfactory adapted behavior.</p> <p>Conclusion</p> <p>Taken together, our results indicate that a relatively long lasting form of adaptation occurs within the axon terminals of the ORNs in the antennal lobes, which depends on intracellular Ca²⁺-stores, attributable to a positive feedback through the GABAergic synapses.</p

Effect of varietal performance on growth attributes and yields of lentil varieties under red and lateritic soil of West Bengal

A field experiment was conducted during rabi season of 2013-14 and 2014-15 at Agriculture Farm of Palli Siksha Bhavana (Institute of Agriculture), Visva-Bharati, Sriniketan, West Bengal to find out the varietal performance of different promising entries of lentil on growth attributes and yield. Tendifferent varieties viz. Subrata, Asha, Ranjan, HUL 57, BM 6, BM 7, PL 406, KLS 218, Moitree and PL 6 was studied in a randomized block design (RBD), replicated thrice. Different growth and yield attributes were measured in the experiment to find out the suitable variety of lentil for the red and lateritic soil zone of West Bengal. The lentil variety PL-406 showed maximum growth potentiality among the other varieties just followed by another long duration lentil variety KLS-218. The lentil variety PL406 showed maximum growth potentiality among the other varieties just followed by another long duration variety KLS 218. Highest grain yield was obtained from the variety Ranjan (789 kg ha-1 ) followed by the variety PL 406 (785 kg ha-1 ) and KLS 218 (783 kg ha-1 ) respectively. From the result of the present experiment, it can be concluded that the variety PL 406 gave maximum vegetative growth, whereas the variety Ranjan produce maximum yield and found most potential variety among other lentil varieties under red and lateritic soil of West Benga

Extraction of Scandium (III) from acidic solutions using organo-phosphoric acid reagents: A comparative study

Comparative and synergistic solvent extraction of Sc(III) using two phosphoric acidic reagents such as di-(2-ethyhexyl) phosphoric acid and 2,4,4,tri-methyl,pentyl-phosphinic acid was investigated. Slope analysis method suggests a cation exchange reaction of Sc(III) with both extractants at a molar ratio of extractant: Sc(III) = 2.5:1 at equilibrium pH< 1.5. The plot of log D vs. log [Extractant] yield the slope (n) value as low as 1.2-1.3 and as high as n=7 at low and high extrcatant concentration level, respectively. Extraction isotherm study predicted the need of 2 stages at A: O=1:4 and A: O=1:3 using 0.1 M D2EHPA and 0.1 M Cyanex 272, respectively. Stripping of Sc (III) was carried out at varied NaOH concentration to ascertain the optimum stripping condition for effective enrichment of metal. The predicted stripping condition (2)-stages with A: O=1:3 and 1:4 for D2EHPA and Cyanex 272, respectively) obtained from Mc-Cabe Thiele plot was further validated by 6-cycles CCS study. An actual leach solution of Mg-Sc alloy bearing 1.0 g/L of Sc (III), 2.5 g/L of Mg and 0.2 M HCl was subjected for selective separation of Sc at the optimum condition. The counter current simulation (CCS) study for both extraction and stripping of actual solution resulted quantitative separation of Sc with ∼12 fold enrichment. The organic phase before and after loading of Sc (III) along with the diluents was characterized by FTIR to ascertain the phase transportation of Sc (III)