RESUMO

Cucumber mosaic virus (CMV) is a tremendous threat to vegetables across the globe, including in Pakistan. The present work was conducted to investigate the genetic variability of CMV isolates infecting pea and spinach vegetables in the Pothwar region of Pakistan. Serological-based surveys during 2016-2017 revealed 31.70% overall CMV disease incidence from pea and spinach crops. Triple-antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) revealed that all the positive isolates belong to CMV subgroup II. Two selected cDNA from ELISA-positive samples representing each pea and spinach crops were PCR-amplified (ca.1100 bp) and sequenced corresponding to the CMV CP gene which shared 93.7% nucleotide identity with each other. Both the sequences of CMV pea (AAHAP) and spinach (AARS) isolates from Pakistan were submitted to GenBank as accession nos. MH119071 and MH119073, respectively. BLAST analysis revealed 93.4% sequence identity of AAHAP isolate with SpK (KC763473) from Iran while AARS isolate shared maximum identity (94.5%) with the strain 241 (AJ585519) from Australia and clustered with some reference isolates of CMV subgroup II from UK (Z12818) and USA (AF127976) in a Neighbour joining phylogenetic reconstruction. A total of 59 polymorphic (segregating) sites (S) with nucleotide diversity (π) of 0.06218 was evident while no INDEL event was observed in Pakistani isolates. The evolutionary distance of Pakistani CMV isolates was recorded as 0.0657 with each other and 0.0574-0.2964 with other CMV isolates reported elsewhere in the world. A frequent gene flow (Fst = 0.30478 <0.33) was observed between Pakistani and earlier reported CMV isolates. In genetic differentiation analysis, the value of three permutation-based statistical tests viz; Z (84.3011), Snn (0.82456), and Ks* (4.04042) were non-significant. The statistical analysis revealed the [...].(AU)

Cucumber mosaic cucumovirus (CMV) é uma tremenda ameaça aos vegetais em todo o mundo, inclusive no Paquistão. O presente trabalho foi conduzido para investigar a variabilidade genética de isolados de CMV infectando vegetais de ervilha e espinafre na região de Pothwar, Paquistão. Pesquisas com base em sorologia durante 2016-2017 revelaram 31,70% da incidência geral da doença por CMV em safras de ervilha e espinafre. O ensaio de imunoabsorção enzimática em sanduíche de anticorpo triplo (TAS-ELISA) revelou que todos os isolados positivos pertencem ao subgrupo II do CMV. Dois cDNA selecionados de amostras positivas para ELISA representando cada safra de ervilha e espinafre foram amplificados por PCR (ca.1100 pb) e sequenciados correspondendo ao gene CMV CP que compartilhou 93,7% de identidade de nucleotídeo um com o outro. Ambas as sequências de isolados de ervilha CMV (AAHAP) e espinafre (AARS) do Paquistão foram submetidas ao GenBank como nos de acesso. MH119071 e MH119073, respectivamente. A análise BLAST revelou 93,4% de identidade de sequência do isolado AAHAP com SpK (KC763473) do Irã, enquanto o isolado AARS compartilhou a identidade máxima (94,5%) com a cepa 241 (AJ585519) da Austrália e agrupada com alguns isolados de referência do subgrupo II de CMV do Reino Unido (Z12818) e EUA (AF127976) em uma reconstrução filogenética vizinha. Um total de 59 sítios polimórficos (segregantes) (S) com diversidade de nucleotídeos (π) de 0,06218 foi evidente, enquanto nenhum evento INDEL foi observado em isolados do Paquistão. A distância evolutiva de isolados de CMV do Paquistão foi registrada como 0,0657 entre si e 0,0574-0,2964 com outros isolados de CMV relatados em outras partes do mundo. Um fluxo gênico frequente (Fst = 0,30478 < 0,33) foi observado entre os isolados de CMV do Paquistão e relatados anteriormente. Na análise de diferenciação genética, os valores de três testes estatísticos baseados em [...].(AU)

Assuntos

RESUMO

Abstract Cucumber mosaic virus (CMV) is a tremendous threat to vegetables across the globe, including in Pakistan. The present work was conducted to investigate the genetic variability of CMV isolates infecting pea and spinach vegetables in the Pothwar region of Pakistan. Serological-based surveys during 2016-2017 revealed 31.70% overall CMV disease incidence from pea and spinach crops. Triple-antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) revealed that all the positive isolates belong to CMV subgroup II. Two selected cDNA from ELISA-positive samples representing each pea and spinach crops were PCR-amplified (ca.1100 bp) and sequenced corresponding to the CMV CP gene which shared 93.7% nucleotide identity with each other. Both the sequences of CMV pea (AAHAP) and spinach (AARS) isolates from Pakistan were submitted to GenBank as accession nos. MH119071 and MH119073, respectively. BLAST analysis revealed 93.4% sequence identity of AAHAP isolate with SpK (KC763473) from Iran while AARS isolate shared maximum identity (94.5%) with the strain 241 (AJ585519) from Australia and clustered with some reference isolates of CMV subgroup II from UK (Z12818) and USA (AF127976) in a Neighbour-joining phylogenetic reconstruction. A total of 59 polymorphic (segregating) sites (S) with nucleotide diversity (π) of 0.06218 was evident while no INDEL event was observed in Pakistani isolates. The evolutionary distance of Pakistani CMV isolates was recorded as 0.0657 with each other and 0.0574-0.2964 with other CMV isolates reported elsewhere in the world. A frequent gene flow (Fst = 0.30478 <0.33) was observed between Pakistani and earlier reported CMV isolates. In genetic differentiation analysis, the value of three permutation-based statistical tests viz; Z (84.3011), Snn (0.82456), and Ks* (4.04042) were non-significant. The statistical analysis revealed the values 2.02535, 0.01468, and 0.71862 of Tajima's D, Fu, & Li's F* and D* respectively, demonstrating that the CMV population is under balancing selection.

Resumo Cucumber mosaic cucumovirus (CMV) é uma tremenda ameaça aos vegetais em todo o mundo, inclusive no Paquistão. O presente trabalho foi conduzido para investigar a variabilidade genética de isolados de CMV infectando vegetais de ervilha e espinafre na região de Pothwar, Paquistão. Pesquisas com base em sorologia durante 2016-2017 revelaram 31,70% da incidência geral da doença por CMV em safras de ervilha e espinafre. O ensaio de imunoabsorção enzimática em sanduíche de anticorpo triplo (TAS-ELISA) revelou que todos os isolados positivos pertencem ao subgrupo II do CMV. Dois cDNA selecionados de amostras positivas para ELISA representando cada safra de ervilha e espinafre foram amplificados por PCR (ca.1100 pb) e sequenciados correspondendo ao gene CMV CP que compartilhou 93,7% de identidade de nucleotídeo um com o outro. Ambas as sequências de isolados de ervilha CMV (AAHAP) e espinafre (AARS) do Paquistão foram submetidas ao GenBank como nos de acesso. MH119071 e MH119073, respectivamente. A análise BLAST revelou 93,4% de identidade de sequência do isolado AAHAP com SpK (KC763473) do Irã, enquanto o isolado AARS compartilhou a identidade máxima (94,5%) com a cepa 241 (AJ585519) da Austrália e agrupada com alguns isolados de referência do subgrupo II de CMV do Reino Unido (Z12818) e EUA (AF127976) em uma reconstrução filogenética vizinha. Um total de 59 sítios polimórficos (segregantes) (S) com diversidade de nucleotídeos (π) de 0,06218 foi evidente, enquanto nenhum evento INDEL foi observado em isolados do Paquistão. A distância evolutiva de isolados de CMV do Paquistão foi registrada como 0,0657 entre si e 0,0574-0,2964 com outros isolados de CMV relatados em outras partes do mundo. Um fluxo gênico frequente (Fst = 0,30478 < 0,33) foi observado entre os isolados de CMV do Paquistão e relatados anteriormente. Na análise de diferenciação genética, os valores de três testes estatísticos baseados em permutação viz, Z (84,3011), Snn (0,82456) e Ks * (4,04042) não foram significativos. A análise estatística revelou os valores 2,02535, 0,01468 e 0,71862 de Tajima's D, Fu, & Li's F * e D * respectivamente, demonstrando que a população de CMV está sob seleção de balanceamento.

Assuntos

RESUMO

Cucumber mosaic virus (CMV) is a tremendous threat to vegetables across the globe, including in Pakistan. The present work was conducted to investigate the genetic variability of CMV isolates infecting pea and spinach vegetables in the Pothwar region of Pakistan. Serological-based surveys during 2016-2017 revealed 31.70% overall CMV disease incidence from pea and spinach crops. Triple-antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) revealed that all the positive isolates belong to CMV subgroup II. Two selected cDNA from ELISA-positive samples representing each pea and spinach crops were PCR-amplified (ca.1100 bp) and sequenced corresponding to the CMV CP gene which shared 93.7% nucleotide identity with each other. Both the sequences of CMV pea (AAHAP) and spinach (AARS) isolates from Pakistan were submitted to GenBank as accession nos. MH119071 and MH119073, respectively. BLAST analysis revealed 93.4% sequence identity of AAHAP isolate with SpK (KC763473) from Iran while AARS isolate shared maximum identity (94.5%) with the strain 241 (AJ585519) from Australia and clustered with some reference isolates of CMV subgroup II from UK (Z12818) and USA (AF127976) in a Neighbour joining phylogenetic reconstruction. A total of 59 polymorphic (segregating) sites (S) with nucleotide diversity (π) of 0.06218 was evident while no INDEL event was observed in Pakistani isolates. The evolutionary distance of Pakistani CMV isolates was recorded as 0.0657 with each other and 0.0574-0.2964 with other CMV isolates reported elsewhere in the world. A frequent gene flow (Fst = 0.30478 <0.33) was observed between Pakistani and earlier reported CMV isolates. In genetic differentiation analysis, the value of three permutation-based statistical tests viz; Z (84.3011), Snn (0.82456), and Ks* (4.04042) were non-significant. The statistical analysis revealed the [...].

Cucumber mosaic cucumovirus (CMV) é uma tremenda ameaça aos vegetais em todo o mundo, inclusive no Paquistão. O presente trabalho foi conduzido para investigar a variabilidade genética de isolados de CMV infectando vegetais de ervilha e espinafre na região de Pothwar, Paquistão. Pesquisas com base em sorologia durante 2016-2017 revelaram 31,70% da incidência geral da doença por CMV em safras de ervilha e espinafre. O ensaio de imunoabsorção enzimática em sanduíche de anticorpo triplo (TAS-ELISA) revelou que todos os isolados positivos pertencem ao subgrupo II do CMV. Dois cDNA selecionados de amostras positivas para ELISA representando cada safra de ervilha e espinafre foram amplificados por PCR (ca.1100 pb) e sequenciados correspondendo ao gene CMV CP que compartilhou 93,7% de identidade de nucleotídeo um com o outro. Ambas as sequências de isolados de ervilha CMV (AAHAP) e espinafre (AARS) do Paquistão foram submetidas ao GenBank como nos de acesso. MH119071 e MH119073, respectivamente. A análise BLAST revelou 93,4% de identidade de sequência do isolado AAHAP com SpK (KC763473) do Irã, enquanto o isolado AARS compartilhou a identidade máxima (94,5%) com a cepa 241 (AJ585519) da Austrália e agrupada com alguns isolados de referência do subgrupo II de CMV do Reino Unido (Z12818) e EUA (AF127976) em uma reconstrução filogenética vizinha. Um total de 59 sítios polimórficos (segregantes) (S) com diversidade de nucleotídeos (π) de 0,06218 foi evidente, enquanto nenhum evento INDEL foi observado em isolados do Paquistão. A distância evolutiva de isolados de CMV do Paquistão foi registrada como 0,0657 entre si e 0,0574-0,2964 com outros isolados de CMV relatados em outras partes do mundo. Um fluxo gênico frequente (Fst = 0,30478 < 0,33) foi observado entre os isolados de CMV do Paquistão e relatados anteriormente. Na análise de diferenciação genética, os valores de três testes estatísticos baseados em [...].

Assuntos

RESUMO

Abstract Cucumber mosaic virus (CMV) is a tremendous threat to vegetables across the globe, including in Pakistan. The present work was conducted to investigate the genetic variability of CMV isolates infecting pea and spinach vegetables in the Pothwar region of Pakistan. Serological-based surveys during 2016-2017 revealed 31.70% overall CMV disease incidence from pea and spinach crops. Triple-antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) revealed that all the positive isolates belong to CMV subgroup II. Two selected cDNA from ELISA-positive samples representing each pea and spinach crops were PCR-amplified (ca.1100 bp) and sequenced corresponding to the CMV CP gene which shared 93.7% nucleotide identity with each other. Both the sequences of CMV pea (AAHAP) and spinach (AARS) isolates from Pakistan were submitted to GenBank as accession nos. MH119071 and MH119073, respectively. BLAST analysis revealed 93.4% sequence identity of AAHAP isolate with SpK (KC763473) from Iran while AARS isolate shared maximum identity (94.5%) with the strain 241 (AJ585519) from Australia and clustered with some reference isolates of CMV subgroup II from UK (Z12818) and USA (AF127976) in a Neighbour-joining phylogenetic reconstruction. A total of 59 polymorphic (segregating) sites (S) with nucleotide diversity () of 0.06218 was evident while no INDEL event was observed in Pakistani isolates. The evolutionary distance of Pakistani CMV isolates was recorded as 0.0657 with each other and 0.0574-0.2964 with other CMV isolates reported elsewhere in the world. A frequent gene flow (Fst = 0.30478 0.33) was observed between Pakistani and earlier reported CMV isolates. In genetic differentiation analysis, the value of three permutation-based statistical tests viz; Z (84.3011), Snn (0.82456), and Ks* (4.04042) were non-significant. The statistical analysis revealed the values 2.02535, 0.01468, and 0.71862 of Tajima's D, Fu, & Lis F* and D* respectively, demonstrating that the CMV population is under balancing selection.

Resumo Cucumber mosaic cucumovirus (CMV) é uma tremenda ameaça aos vegetais em todo o mundo, inclusive no Paquistão. O presente trabalho foi conduzido para investigar a variabilidade genética de isolados de CMV infectando vegetais de ervilha e espinafre na região de Pothwar, Paquistão. Pesquisas com base em sorologia durante 2016-2017 revelaram 31,70% da incidência geral da doença por CMV em safras de ervilha e espinafre. O ensaio de imunoabsorção enzimática em sanduíche de anticorpo triplo (TAS-ELISA) revelou que todos os isolados positivos pertencem ao subgrupo II do CMV. Dois cDNA selecionados de amostras positivas para ELISA representando cada safra de ervilha e espinafre foram amplificados por PCR (ca.1100 pb) e sequenciados correspondendo ao gene CMV CP que compartilhou 93,7% de identidade de nucleotídeo um com o outro. Ambas as sequências de isolados de ervilha CMV (AAHAP) e espinafre (AARS) do Paquistão foram submetidas ao GenBank como nos de acesso. MH119071 e MH119073, respectivamente. A análise BLAST revelou 93,4% de identidade de sequência do isolado AAHAP com SpK (KC763473) do Irã, enquanto o isolado AARS compartilhou a identidade máxima (94,5%) com a cepa 241 (AJ585519) da Austrália e agrupada com alguns isolados de referência do subgrupo II de CMV do Reino Unido (Z12818) e EUA (AF127976) em uma reconstrução filogenética vizinha. Um total de 59 sítios polimórficos (segregantes) (S) com diversidade de nucleotídeos () de 0,06218 foi evidente, enquanto nenhum evento INDEL foi observado em isolados do Paquistão. A distância evolutiva de isolados de CMV do Paquistão foi registrada como 0,0657 entre si e 0,0574-0,2964 com outros isolados de CMV relatados em outras partes do mundo. Um fluxo gênico frequente (Fst = 0,30478 0,33) foi observado entre os isolados de CMV do Paquistão e relatados anteriormente. Na análise de diferenciação genética, os valores de três testes estatísticos baseados em permutação viz, Z (84,3011), Snn (0,82456) e Ks * (4,04042) não foram significativos. A análise estatística revelou os valores 2,02535, 0,01468 e 0,71862 de Tajimas D, Fu, & Lis F * e D * respectivamente, demonstrando que a população de CMV está sob seleção de balanceamento.

RESUMO

Cucumber mosaic virus (CMV) is a tremendous threat to vegetables across the globe, including in Pakistan. The present work was conducted to investigate the genetic variability of CMV isolates infecting pea and spinach vegetables in the Pothwar region of Pakistan. Serological-based surveys during 2016-2017 revealed 31.70% overall CMV disease incidence from pea and spinach crops. Triple-antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) revealed that all the positive isolates belong to CMV subgroup II. Two selected cDNA from ELISA-positive samples representing each pea and spinach crops were PCR-amplified (ca.1100 bp) and sequenced corresponding to the CMV CP gene which shared 93.7% nucleotide identity with each other. Both the sequences of CMV pea (AAHAP) and spinach (AARS) isolates from Pakistan were submitted to GenBank as accession nos. MH119071 and MH119073, respectively. BLAST analysis revealed 93.4% sequence identity of AAHAP isolate with SpK (KC763473) from Iran while AARS isolate shared maximum identity (94.5%) with the strain 241 (AJ585519) from Australia and clustered with some reference isolates of CMV subgroup II from UK (Z12818) and USA (AF127976) in a Neighbour-joining phylogenetic reconstruction. A total of 59 polymorphic (segregating) sites (S) with nucleotide diversity (π) of 0.06218 was evident while no INDEL event was observed in Pakistani isolates. The evolutionary distance of Pakistani CMV isolates was recorded as 0.0657 with each other and 0.0574-0.2964 with other CMV isolates reported elsewhere in the world. A frequent gene flow (Fst = 0.30478 <0.33) was observed between Pakistani and earlier reported CMV isolates. In genetic differentiation analysis, the value of three permutation-based statistical tests viz; Z (84.3011), Snn (0.82456), and Ks* (4.04042) were non-significant. The statistical analysis revealed the values 2.02535, 0.01468, and 0.71862 of Tajima's D, Fu, & Li's F* and D* respectively, demonstrating that the CMV population is under balancing selection.

Assuntos

RESUMO

A set of sixty inbred lines of maize (Zea mays L.) were screened in the greenhouse at the seedling stage under both normal and water-deficit conditions. Six water deficit-tolerant inbred lines were selected based on root to shoot ratios. These selected lines were crossed in a diallel pattern. The parental, F1, and reciprocal cross plants were planted in a field under both normal and water-deficit conditions. Normal irrigation was applied to the control set, while the water-deficit set received 50% of normal irrigation levels. Analyses of variance of various morpho-physiological parameters identified significant differences among the selected lines under both conditions, indicating the presence of significant genetic variability. Variance components for general combining ability (GCA), specific combining ability (SCA), and reciprocal effects for all the parameters were estimated to determine the relative importance of additive and non-additive or dominance type of gene action. Variance components for GCA were larger than for SCA indicating the preponderance of additive types of gene action for all the traits under study. Hybrids developed from inbred lines W-10 and W-64SP proved to have the best grain yield under normal and water-deficit conditions. Under water-deficit conditions, the best performing cross was B-34 x W-10. Hence, these inbred lines and the hybrids might be of value in future breeding programs.

Assuntos

RESUMO

We report observation of the electroweak production of single top quarks in pp[over ] collisions at sqrt[s]=1.96 TeV based on 2.3 fb(-1) of data collected by the D0 detector at the Fermilab Tevatron Collider. Using events containing an isolated electron or muon and missing transverse energy, together with jets originating from the fragmentation of b quarks, we measure a cross section of sigma(pp[over ]--> tb + X, tqb + X) = 3.94 + or - 0.88 pb. The probability to measure a cross section at this value or higher in the absence of signal is 2.5 x 10(-7), corresponding to a 5.0 standard deviation significance for the observation.

RESUMO

We present a search for a narrow resonance in the inclusive diphoton final state using approximately 2.7 fb(-1) of data collected with the D0 detector at the Fermilab Tevatron pp Collider. We observe good agreement between the data and the background prediction, and set the first 95% C.L. upper limits on the production cross section times the branching ratio for decay into a pair of photons for resonance masses between 100 and 150 GeV. This search is also interpreted in the context of several models of electroweak symmetry breaking with a Higgs boson decaying into two photons.

RESUMO

We present a search for direct CP violation in B(+/-)-->J/psiK(+/-)(pi(+/-)) decays. The event sample is selected from 2.8 fb(-1) of pp collisions recorded by D0 experiment in run II of the Fermilab Tevatron Collider. The charge asymmetry A_(CP)(B(+)-->J/psiK(+))= + 0.0075 +/- 0.0061(stat)+/-0.0030(syst) is obtained using a sample of approximately 40, 000 B(+/-)-->J/psiK(+/-) decays. The achieved precision is of the same level as the expected deviation predicted by some extensions of the standard model. We also measured the charge asymmetry A(CP)(B(+)-->J/psipi(+))=-0.09+/-0.08(stat)+/-0.03(syst).

RESUMO

We search for the production of a heavy W' gauge boson that decays to third generation quarks in 0.9 fb-1 of pp collisions at square root(s)=1.96 TeV, collected with the D0 detector at the Fermilab Tevatron collider. We find no significant excess in the final-state invariant mass distribution and set upper limits on the production cross section times branching fraction. For a left-handed W' boson with SM couplings, we set a lower mass limit of 731 GeV. For right-handed W' bosons, we set lower mass limits of 739 GeV if the W' boson decays to both leptons and quarks and 768 GeV if the W' boson decays only to quarks. We also set limits on the coupling of the W' boson to fermions as a function of its mass.

RESUMO

We present a search for associated Higgs boson production in the process pp-->WH-->WWW*-->l;+/-nul'+/-nu'+X in final states containing two like-sign isolated electrons or muons (e+/-e;+/-, e+/-micro+/-, or micro+/-micro+/-). The search is based on D0 run II data samples corresponding to integrated luminosities of 360-380 pb-1. No excess is observed over the predicted standard model background. We set 95% C.L. upper limits on sigma(pp-->WH)xBr(H-->WW*) between 3.2 and 2.8 pb for Higgs boson masses from 115 to 175 GeV.

RESUMO

A search for associated production of charginos and neutralinos is performed using data recorded with the D0 detector at a pp center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider. This analysis considers final states with missing transverse energy and three charged leptons, of which at least two are electrons or muons. No evidence for supersymmetry is found in a data set corresponding to an integrated luminosity of 320 pb-1. Limits on the product of the production cross section and leptonic branching fraction are set. For the minimal supergravity model, a chargino lower mass limit of 117 GeV at the 95% C.L. is derived in regions of parameter space with enhanced leptonic branching fractions.

RESUMO

We have performed a search for neutral Higgs bosons produced in association with bottom quarks in pp collisions, using 260 pb-1 of data collected with the D0 detector in Run II of the Fermilab Tevatron Collider. The cross sections for these processes are enhanced in many extensions of the standard model (SM), such as in its minimal supersymmetric extension at large tanbeta. The results of our analysis agree with expectations from the SM, and we use our measurements to set upper limits on the production of neutral Higgs bosons in the mass range of 90 to 150 GeV.