The Experts below are selected from a list of 171 Experts worldwide ranked by ideXlab platform
Rodrigo P P Almeida - One of the best experts on this subject based on the ideXlab platform.
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detection characterisation and transmission by Macrosteles leafhoppers of watercress yellows phytoplasma in hawaii
Annals of Applied Biology, 2006Co-Authors: Wayne B Borth, S K Fukuda, Randall T Hamasaki, J S Hu, Rodrigo P P AlmeidaAbstract:A new yellows disease of watercress (Nasturtium officinale) in Hawaii has symptoms of reduced leaf size, leaf yellowing and crinkling, and occasionally witches’ brooms. This disease is found on all watercress farms on Oahu but has not yet been found on other Hawaiian islands. Watercress plants were tested for phytoplasma infection by polymerase chain reaction assays using phytoplasma-specific primers. Amplicons of the expected sizes were produced from all symptomatic plants but not from healthy plants raised from seed. Phylogenetic analysis of the 16S rRNA gene indicated that watercress yellows was caused by a phytoplasma in the aster yellows group, with sequence similarity to onion yellows from Japan. Six weed species collected from the vicinity of affected watercress farms, Amaranth sp., Eclipta prostrata, Emilia sonchifolia, Plantago major, Myriophyllum aquaticum and Sonchus oleraceus, were also determined to be hosts of this phytoplasma. Leafhoppers, identified as Macrosteles sp. (Hemiptera, Cicadellidae), collected from symptomatic watercress transmitted this phytoplasma to watercress, plantain and lettuce (Lactuca sativa) in greenhouse experiments.
Wayne B Borth - One of the best experts on this subject based on the ideXlab platform.
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detection characterisation and transmission by Macrosteles leafhoppers of watercress yellows phytoplasma in hawaii
Annals of Applied Biology, 2006Co-Authors: Wayne B Borth, S K Fukuda, Randall T Hamasaki, J S Hu, Rodrigo P P AlmeidaAbstract:A new yellows disease of watercress (Nasturtium officinale) in Hawaii has symptoms of reduced leaf size, leaf yellowing and crinkling, and occasionally witches’ brooms. This disease is found on all watercress farms on Oahu but has not yet been found on other Hawaiian islands. Watercress plants were tested for phytoplasma infection by polymerase chain reaction assays using phytoplasma-specific primers. Amplicons of the expected sizes were produced from all symptomatic plants but not from healthy plants raised from seed. Phylogenetic analysis of the 16S rRNA gene indicated that watercress yellows was caused by a phytoplasma in the aster yellows group, with sequence similarity to onion yellows from Japan. Six weed species collected from the vicinity of affected watercress farms, Amaranth sp., Eclipta prostrata, Emilia sonchifolia, Plantago major, Myriophyllum aquaticum and Sonchus oleraceus, were also determined to be hosts of this phytoplasma. Leafhoppers, identified as Macrosteles sp. (Hemiptera, Cicadellidae), collected from symptomatic watercress transmitted this phytoplasma to watercress, plantain and lettuce (Lactuca sativa) in greenhouse experiments.
J Le J Roux - One of the best experts on this subject based on the ideXlab platform.
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molecular data reveals california as the potential source of an invasive leafhopper species Macrosteles sp nr severini transmitting the aster yellows phytoplasma in hawaii
Annals of Applied Biology, 2009Co-Authors: J Le J Roux, Daniel RubinoffAbstract:A species of aster leafhopper (Macrosteles sp.) became established in 2001 on Oahu, Hawaii, and through the transmission of the aster yellows phytoplasma, caused devastating losses to the island’s watercress industry. DNA sequence data were analysed from two mitochondrial genes [cytochrome oxidase subunit 1(CO1) and nicotinamide adenine dinucleotide 1 (NADH1)] and one nuclear gene (wingless, Wg) (combined total of 1874 bp) to reconstruct phylogenetic relationships between putative US mainland source populations of aster leafhoppers and those introduced to Hawaii. These data were applied to elucidate the origin(s) and identity of Hawaiian infestations and the amount of genetic diversity within introduced invasive populations. Both phylogenetic search criteria (Bayesian and maximum likelihood models) converged onto similar tree topologies for all three gene regions and suggested that Hawaii infestations represent a single undescribed leafhopper species unrelated to the common aster leafhopper, Macrosteles quadrilineatus. An exact haplotype match was found from a specimen intercepted from watercress shipped to Hawaii from Los Angeles, California, suggesting this region as the potential source for Hawaiian infestations. Two mitochondrial haplotypes were identified in Hawaii suggesting two or perhaps just a single introduction of more than one female.
Marcin Walczak - One of the best experts on this subject based on the ideXlab platform.
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sulcia symbiont of the leafhopper Macrosteles laevis ribaut 1927 insecta hemiptera cicadellidae deltocephalinae harbors arsenophonus bacteria
Protoplasma, 2016Co-Authors: Michal Kobialka, Marcin Walczak, Anna Michalik, łukasz Junkiert, Teresa SzklarzewiczAbstract:The leafhopper Macrosteles laevis, like other plant sap-feeding hemipterans, lives in obligate symbiotic association with microorganisms. The symbionts are harbored in the cytoplasm of large cells termed bacteriocytes, which are integrated into huge organs termed bacteriomes. Morphological and molecular investigations have revealed that in the bacteriomes of M. laevis, two types of bacteriocytes are present which are as follows: bacteriocytes with bacterium Sulcia and bacteriocytes with Nasuia symbiont. We observed that in bacteriocytes with Sulcia, some cells of this bacterium contain numerous cells of the bacterium Arsenophonus. All types of symbionts are transmitted transovarially between generations. In the mature female, the bacteria Nasuia, bacteria Sulcia, and Sulcia with Arsenophonus inside are released from the bacteriocytes and start to assemble around the terminal oocytes. Next, the bacteria enter the cytoplasm of follicular cells surrounding the posterior pole of the oocyte. After passing through the follicular cells, the symbionts enter the space between the oocyte and follicular epithelium, forming a characteristic “symbiont ball.”
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New records of leafhoppers for Poland (Hemiptera: Cicadomorpha)
Polish Journal of Entomology, 2011Co-Authors: Dariusz Świerczewski, Marcin WalczakAbstract:New records of leafhoppers for Poland (Hemiptera: Cicadomorpha) The paper presents data on the distribution and biology of five leafhopper species new to the Polish fauna: Eupteryx lelievrei (Lethierry, 1874), Zyginidia pullula (Boheman, 1845), Zygina schneideri (Günthart, 1974), Macrosteles sardus Ribaut, 1948 and Metalimnus steini (Fieber, 1869).
Daniel Rubinoff - One of the best experts on this subject based on the ideXlab platform.
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molecular data reveals california as the potential source of an invasive leafhopper species Macrosteles sp nr severini transmitting the aster yellows phytoplasma in hawaii
Annals of Applied Biology, 2009Co-Authors: J Le J Roux, Daniel RubinoffAbstract:A species of aster leafhopper (Macrosteles sp.) became established in 2001 on Oahu, Hawaii, and through the transmission of the aster yellows phytoplasma, caused devastating losses to the island’s watercress industry. DNA sequence data were analysed from two mitochondrial genes [cytochrome oxidase subunit 1(CO1) and nicotinamide adenine dinucleotide 1 (NADH1)] and one nuclear gene (wingless, Wg) (combined total of 1874 bp) to reconstruct phylogenetic relationships between putative US mainland source populations of aster leafhoppers and those introduced to Hawaii. These data were applied to elucidate the origin(s) and identity of Hawaiian infestations and the amount of genetic diversity within introduced invasive populations. Both phylogenetic search criteria (Bayesian and maximum likelihood models) converged onto similar tree topologies for all three gene regions and suggested that Hawaii infestations represent a single undescribed leafhopper species unrelated to the common aster leafhopper, Macrosteles quadrilineatus. An exact haplotype match was found from a specimen intercepted from watercress shipped to Hawaii from Los Angeles, California, suggesting this region as the potential source for Hawaiian infestations. Two mitochondrial haplotypes were identified in Hawaii suggesting two or perhaps just a single introduction of more than one female.
