Morphological, ecological and biological variations in the mustard aphid, Lipaphis pseudobrassicae (Kaltenbach) (Hemiptera: Aphididae) from different host plants

B.K. Agarwala,Kalpana Das,Parichita Raychoudhury 한국응용곤충학회 2009 Journal of Asia-Pacific Entomology Vol.12 No.3

Genetic and morphological differentiation of insect populations in relation to the use of different host plants is an important phenomenon that leads to ecological specialization. In this study, we describe variations in morphology, and in ecological and biological parameters of Lipaphis pseudobrassicae (Kaltenbach) clones associated with three host species of Cruciferae, Brassica juncea (L.) var. rai sarson Czern and Cross (brown mustard), Brassica campestris L. var. sarson Prain (yellow mustard), and Rorippa indica (L.) Hiern (wild herb). This study was aimed at obtaining evidence regarding phenotypic differentiation induced by, or associated with, the use of distinct host species. Ten morphological characters, 4 growth parameters and 8 biological functions were investigated in wingless aphids collected from plants of the three host species. Aphids from B. campestris and B. juncea clones were bigger in size, heavier in weight and showed higher growth rates and fecundity than the clones from R. indica. Between the two crop plants, clones from B. juncea showed significantly higher growth rates than the clones from B. campestris. Transfer of L. pseudobrassicae populations from B. campestris to B. juncea and R. indica and vice versa resulted in poor performance. Results indicate that the average phenotype of L. pseudobrassicae individuals inhabiting different host plant species differs as a consequence of the contrasting feeding environments the host species provide. Genetic and morphological differentiation of insect populations in relation to the use of different host plants is an important phenomenon that leads to ecological specialization. In this study, we describe variations in morphology, and in ecological and biological parameters of Lipaphis pseudobrassicae (Kaltenbach) clones associated with three host species of Cruciferae, Brassica juncea (L.) var. rai sarson Czern and Cross (brown mustard), Brassica campestris L. var. sarson Prain (yellow mustard), and Rorippa indica (L.) Hiern (wild herb). This study was aimed at obtaining evidence regarding phenotypic differentiation induced by, or associated with, the use of distinct host species. Ten morphological characters, 4 growth parameters and 8 biological functions were investigated in wingless aphids collected from plants of the three host species. Aphids from B. campestris and B. juncea clones were bigger in size, heavier in weight and showed higher growth rates and fecundity than the clones from R. indica. Between the two crop plants, clones from B. juncea showed significantly higher growth rates than the clones from B. campestris. Transfer of L. pseudobrassicae populations from B. campestris to B. juncea and R. indica and vice versa resulted in poor performance. Results indicate that the average phenotype of L. pseudobrassicae individuals inhabiting different host plant species differs as a consequence of the contrasting feeding environments the host species provide.

Complete characterization of graphs for direct comparing Zagreb indices

Horoldagva, B.,Das, K.Ch.,Selenge, T.A. North Holland ; Elsevier Science Ltd 2016 Discrete Applied Mathematics Vol.215 No.-

<P>The classical first and second Zagreb indices of a graph G are defined as M-1(G) = Sigma(v is an element of V) d(G)(v)(2) and M-2(G) = Sigma(uv is an element of E(G)) d(G)(u) d(G)(V), where d(G)(v) is the degree of the vertex v of graph G. Recently, Furtula et al. (2014) studied the difference between the Zagreb indices and mentioned a problem to characterize the graphs for which M-1(G) > M-2 (G) or M-1(G) < M-2 (G) or M-1(G) = M-2 (G). In this paper we completely solve this problem. (C) 2016 Elsevier B.V. All rights reserved.</P>

Remoteness and distance eigenvalues of a graph

Lin, H.,Das, K.Ch.,Wu, B. North Holland ; Elsevier Science Ltd 2016 Discrete Applied Mathematics Vol.215 No.-

<P>Let G be a connected graph of order n with diameter d. Remoteness rho of G is the maximum average distance from a vertex to all others and partial derivative(1) >= ... >= partial derivative(n) are the distance eigenvalues of G. Aouchiche and Hansen (0000), Aouchiche and Hansen conjectured that rho + partial derivative(3) > 0 when d >= 3 and rho + partial derivative(left perpendicular7d//right perpendicular) > 0. In this paper, we confirm these two conjectures. Furthermore, we give lower bounds on partial derivative(n) + rho and partial derivative(1) - rho when G not congruent to K-n and the extremal graphs are characterized. (C) 2016 Elsevier B.V. All rights reserved.</P>

Seasonal Impact of Microsporidian Infection on the Reproductive Potential of Silkworm, Bombyx mori L. (Lepidoptera: Bombycidae)

Mohanan N. Madana,Krishnan N.,Mitra P.,Das N. K.,Saratchandra B.,Haldar D. P. Korean Society of Sericultural Science 2005 International Journal of Industrial Entomology Vol.11 No.2

Impact of microsporidian infection and season on reproductive potential of Bombyx mori L. was investigated in the laboratory. Microsporidian infection significantly (P<0.01) reduced fecundity and hatching and increased sterility and mortality of eggs. Among the microsporidia, Nosema sp. 2 infected silkworm produced eggs with least fecundity and hatching percent as well as highest dead and sterile eggs followed by Nosema sp. 1 and N. bombycis. Microsporidia, in general, significantly reduced fecundity and hatching percent of eggs and increased number of dead and sterile eggs in all the three seasons except N. bombycis in July - August (S3) and Nosema sp. 2 in January February (S1). Since, seed production is the anchor sheet of mulberry sericulture, coefficient of egg lying is considered as an important aspect and the industry quite often facing shortage of disease free layings. The present study indicates that B. mori is more susceptible to microsporidia during S2 followed by S3 and S1 and Nosema sp2. is most virulent followed by Nosema spl. and N. bombycis.

Highly Efficient Photocatalytic Studies on Bi36 Fe2 O57 Ceramic Synthesized by Chemical Route

Manish Kumar Verma,Vinod Kumar,Upakar Patel,Vishnu Shankar Rai,Anup Kumar,Arup Kumar De,Aditya Kumar Prajapati,Dinesh Prajapati,Kedar Sahoo,Tapas Das,N. B. Singh,K. D. Mandal 한국전기전자재료학회 2023 Transactions on Electrical and Electronic Material Vol.24 No.5

Bi36 Fe2 O57 (BFO) polycrystalline ceramic was synthesized by economical chemical route. The single-phase formation of BFO ceramic was confirmed by powder X-ray diffraction studies. Nanosized formation of BFO ceramics established by XRD and TEM analysis. The bimodal distribution of grain size is observed with size ranging from 50 to 600 nm. It observed that the Bi36 Fe2 O57 photocatalyst exhibited higher catalytic activity for the degradation of Methylene Blue (MB) under visible-light irradiation The oxidation state of elements present in the BFO ceramic, was confirmed by XPS studies. The pseudocapacitive nature of BFO ceramic was observed by cyclic Voltammetry. The dielectric constant of BFO ceramic was found 375 at 1 kHz at 300 K. The dielectric loss was found 0.51 at 100 kHz and 300 K.

Microstructural comparison of Zr_73.5Nb₉Cu₇Ni₁Al_9.5 nanostructure-dendrite composites produced by different casting techniques

Kim, K.B.,Das, J.,Lö,ser, W.,Lee, M.H.,Kim, D.H.,Roy, S.K.,Eckert, J. Elsevier 2007 Materials science & engineering. properties, micro Vol.449 No.-

<P><B>Abstract</B></P><P>Zr<SUB>73.5</SUB>Nb<SUB>9</SUB>Cu<SUB>7</SUB>Ni<SUB>1</SUB>Al<SUB>9.5</SUB> (numbers indicate at.%) nanostructure-dendrite composites were fabricated using three different casting techniques: suction casting, centrifugal casting and arc-melting. The microstructure of the suction casting sample consists of micrometer-scale dendrites in a nanostructured matrix. However, some areas in the matrix contain nano-scale crystals together with an amorphous phase revealing an inhomogeneity of the specimen. On the contrary, the microstructures of the centrifugally-cast and the arc-melted samples are overall homogeneous, consisting of micrometer-scale dendrites that are homogeneously distributed in a nanostructured matrix. The dendrites correspond to a body centered cubic (bcc) β-Zr phase, whereas the nanostructured matrix consists of body centered tetragonal (bct) Zr<SUB>2</SUB>Cu-type and hexagonal close-packed (hcp) MgZn<SUB>2</SUB>-type phases. The comparison of the microstructures of these two alloys reveals that the formation of nano-scale twins and a disordered ω-phase in the β-Zr dendrites only happens in the centrifugally-cast sample. The differences in the phases and the microstructures between the differently prepared samples significantly influence the corresponding mechanical properties of the specimens.</P>

Influence of Level of Dietary Inorganic and Organic Copper and Energy Level on the Performance and Nutrient Utilization of Broiler Chickens

Das, T.K.,Mondal, M.K.,Biswas, P.,Bairagi, B.,Samanta, C.C. Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.1

An experiment was conducted to determine the influence of dietary inorganic (copper sulfate) and organic (copper proteinate) forms of copper and energy level on performance and nutrient utilization of broiler chickens. Two hundred day-old commercial Vencobb broiler chicks were purchased and randomly distributed to 20 cages of 10 birds each. These replicates were randomly assigned to one of five treatments in a (($2{\times}2$)+1) factorial arrangement. These two factors were sources of Cu ($CuSO_{4}$ vs. Cuproteinate) and dose of Cu supplements (200 mg and 400 mg/kg dietary dry matter) and the control (no supplemental Cu). After the starter period (up to 3 weeks), from d 22 onwards another factor i.e. energy at two levels (2,900 vs. 2,920 kcal/kg diet) was introduced with the previous factorial arrangements by subdividing each replicate into two equal parts, for two energy levels, without disturbing the dose and source of Cu supplement. Cu-salt supplementation linearly increased (p<0.01) live weight (LW), live weight gain (LWG) and feed conversion ratio (FCR) at 3 weeks, whereas cumulative feed intake (CFI) was unaffected (p>0.05). LWG and FCR were higher (p<0.01) in Cu-proteinate supplemented birds compared to $CuSO_{4}$ supplementation. A linear dose response (p<0.01) of Cu was found for the performance of broiler chickens. Birds having a higher energy level in the finisher stage increased (p<0.01) LWG and FCR. Cumulative feed intake was similar (p>0.05) across the groups up to the 5th week. Cu-proteinate increased performance of broiler chickens compared to $CuSO_{4}$. Dose of supplemental Cu-salt irrespective of source showed a linear response (p<0.01) for performance. Supplementation of Cu-proteinate increased metabolizability of DM (p<0.01), NFE (p<0.05), total carbohydrate (p<0.01) and OM (p<0.01) at the starter period. Increased dose of Cu-salt linearly increased (p<0.01) metabolizability of DM, CP, CF, NFE and OM. Higher energy level in the diet improved DM (p<0.05), EE (p<0.01), NFE (p = 0.01), total carbohydrate (p<0.01) and OM (p<0.01) metabolizability. Cu-proteinate supplementation showed better nutrient utilization compared to CuSO4. Dose of Cu linearly increased DM, CP, EE, NFE, total carbohydrate and OM metabolizability. CF metabolizability was unaffected (p>0.05) among the treatments. In conclusion, dietary supplementation of Cu-salt more than the requirement may improve performance and nutrient utilization in broiler chickens even with a high energy finisher diet. Cu-proteinate showed better performance and nutrient utilization compared to $CuSO_{4}$.

Edge Browning and Microbial Quality of Fresh-cut Iceberg Lettuce with Different Sanitizers and Contact Times

Das, B.K.,Kim, J.G.,Choi, J.W. AKADEMIIA NA SELSKOSTOPANSKITE NAUKI 2011 Bulgarian journal of agricultural science Vol.17 No.1

ROLE OF DIFFERENT WASHING SOLUTIONS AND CONTACT TIME ON THE MICROBIAL QUALITY AND FOOD SAFETY OF FRESH-CUT PAPRIKA

Das, B.K.,Ji Gang Kim,,Ji Weon Choi, International Society for Horticultural Science (I 2010 Acta Horticulturae Vol.875 No.-

Sum-connectivity index of a graph

Das, K. C.,Das, S.,Zhou, B. John Wiley Sons, Ltd 2016 Frontiers of mathematics in China Vol.11 No.1

<P>Let G be a simple connected graph, and let d (i) be the degree of its i-th vertex. The sum-connectivity index of the graph G is defined as . We discuss the effect on chi(G) of inserting an edge into a graph. Moreover, we obtain the relations between sum-connectivity index and RandiA double dagger index.</P>