Species abundance and influence of nematodes in urban turfgrass ecosystems in East Baton Rouge Parish, Louisiana

In 2011 and 2012, 100 residential lawns in the Baton Rouge, LA area were sampled to document the incidence of plant-parasitic nematodes, in addition four full-season microplot experiments and four 71-day duration greenhouse experiments were conducted to evaluate their pathogenicity on St. Augustine and centipede turfgrasses. Nematode genera associated with both turfgrasses included Criconemella, Helicotylenchus, Meloidogyne, Pratylenchus, Tylenchorynchus and Tylenchus spp. In microplot trials in 2012, nematodes did not cause significant damage to either turfgrass, but soil exhibited an effect on plant growth parameters. In 2013, when there was significant nematode related injury to both turfgrasses, there were no significant effects of soil on plant growth parameters. Greenhouse based pathogenicity trials were conducted separately with Meloidogyne incognita and Pratylenchus zeae. Across two levels of nematode infestation, reductions below controls for St. Augustine and centipede averaged 24% and 28% for M. incognita and 37.0% and 39.3% for P. zeae; indicating that overall, P. zeae was more damaging than M. incognita to both turfgrasses

Influence of plant-parasitic nematodes on growth of St. Augustine and centipede turfgrasses

During the spring, summer and fall (May-November) of 2011 and 2012, 100 residential lawns in East Baton Rouge Parish, LA, were sampled to document the incidence and abundance of plant-parasitic nematode communities. Genera of nematodes associated with St. Augustine and centipede turfgrasses included Criconemella, Helicotylenchus, Meloidogyne, Pratylenchus, Tylenchorhynchus, and Tylenchus. Damage potentials of Meloidogyne incognita and Pratylenchus zeae individually were evaluated in subsequent greenhouse trials. Across nematode infestation levels of 200 and 2,000 individuals, reductions in final plant weight below controls for St. Augustine and centipede averaged 24% and 28%, respectively, for M. incognita and 37.0% and 39.3% for P. zeae; indicating that overall, P. zeae was more damaging to both turfgrasses than M. incognita

Evaluation of damage potential of urban turf-associated nematode communities under microplot conditions and influence of soil type on nematode reproduction

Two full-season microplot experiments were conducted to evaluate the damage potential of a plant-parasitic nematode community on St. Augustine and centipede turfgrasses grown in three soil types and to assess the influence of soil type on reproduction of the nematode populations comprising the community. Genera of nematodes associated with both turfgrasses included Criconemella, Helicotylenchus, Meloidogyne, Pratylenchus, Tylenchorynchus, and Tylenchus spp. In 2012, nematodes did not cause significant damage to either turfgrass, but soil type affected plant growth parameters. In 2013, there was significant nematode-related injury to both turfgrasses, but there were no significant effects of soil type on plant growth parameters

Morphological and Molecular Characterization of Pratylenchus dakotaensis n. sp. (Nematoda: Pratylenchidae), a New Root-Lesion Nematode Species on Soybean in North Dakota, USA

Root-lesion nematodes (Pratylenchus spp.) of the genus Pratylenchus Filipjev, 1936, are among the most important nematode pests on soybean (Glycine max (L.) Merr.), along with soybean cyst and root-knot nematodes. In May 2015 and 2016, a total of six soil samples were collected from a soybean field in Walcott, Richland County, ND and submitted to the Mycology and Nematology Genetic Diversity and Biology Laboratory (MNGDBL), USDA, ARS, MD for analysis. Later, in 2019, additional nematodes recovered from a greenhouse culture on soybean originally from the same field were submitted for further analysis. Males, females, and juveniles of Pratylenchus sp. were recovered from soil and root samples and were examined morphologically and molecularly. DNA from single nematodes were extracted, and the nucleotides feature of three genomic regions targeting on the D2–D3 region of 28S rDNA and ITS rDNA and mitochondrial cytochrome oxidase subunit I (COX1) gene were characterized. Phylogeny trees were constructed to ascertain the relationships with other Pratylenchus spp., and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed to provide a rapid and reliable differentiation from other common Pratylenchus spp. Molecular features indicated that it is a new, unnamed Pratylenchus sp. that is different from morphologically closely related Pratylenchus spp., including P. convallariae, P. pratensis, P. fallax, and P. flakkensis. In conclusion, both morphological and molecular observations indicate that the North Dakota isolate on soybean represents a new root-lesion nematode species which is named and described herein as Pratylenchus dakotaensis n. sp

Morphological and Molecular Characterization of <i>Pratylenchus dakotaensis</i> n. sp. (Nematoda: Pratylenchidae), a New Root-Lesion Nematode Species on Soybean in North Dakota, USA

Root-lesion nematodes (Pratylenchus spp.) of the genus Pratylenchus Filipjev, 1936, are among the most important nematode pests on soybean (Glycine max (L.) Merr.), along with soybean cyst and root-knot nematodes. In May 2015 and 2016, a total of six soil samples were collected from a soybean field in Walcott, Richland County, ND and submitted to the Mycology and Nematology Genetic Diversity and Biology Laboratory (MNGDBL), USDA, ARS, MD for analysis. Later, in 2019, additional nematodes recovered from a greenhouse culture on soybean originally from the same field were submitted for further analysis. Males, females, and juveniles of Pratylenchus sp. were recovered from soil and root samples and were examined morphologically and molecularly. DNA from single nematodes were extracted, and the nucleotides feature of three genomic regions targeting on the D2–D3 region of 28S rDNA and ITS rDNA and mitochondrial cytochrome oxidase subunit I (COX1) gene were characterized. Phylogeny trees were constructed to ascertain the relationships with other Pratylenchus spp., and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed to provide a rapid and reliable differentiation from other common Pratylenchus spp. Molecular features indicated that it is a new, unnamed Pratylenchus sp. that is different from morphologically closely related Pratylenchus spp., including P. convallariae, P. pratensis, P. fallax, and P. flakkensis. In conclusion, both morphological and molecular observations indicate that the North Dakota isolate on soybean represents a new root-lesion nematode species which is named and described herein as Pratylenchus dakotaensis n. sp

Intracellular nicotinamide adenine dinucleotide promotes TNF-induced necroptosis in a sirtuin-dependent manner.

Cellular necrosis has long been regarded as an incidental and uncontrolled form of cell death. However, a regulated form of cell death termed necroptosis has been identified recently. Necroptosis can be induced by extracellular cytokines, pathogens and several pharmacological compounds, which share the property of triggering the formation of a RIPK3-containing molecular complex supporting cell death. Of interest, most ligands known to induce necroptosis (including notably TNF and FASL) can also promote apoptosis, and the mechanisms regulating the decision of cells to commit to one form of cell death or the other are still poorly defined. We demonstrate herein that intracellular nicotinamide adenine dinucleotide (NAD(+)) has an important role in supporting cell progression to necroptosis. Using a panel of pharmacological and genetic approaches, we show that intracellular NAD(+) promotes necroptosis of the L929 cell line in response to TNF. Use of a pan-sirtuin inhibitor and shRNA-mediated protein knockdown led us to uncover a role for the NAD(+)-dependent family of sirtuins, and in particular for SIRT2 and SIRT5, in the regulation of the necroptotic cell death program. Thus, and in contrast to a generally held view, intracellular NAD(+) does not represent a universal pro-survival factor, but rather acts as a key metabolite regulating the choice of cell demise in response to both intrinsic and extrinsic factors.Cell Death and Differentiation advance online publication, 22 May 2015; doi:10.1038/cdd.2015.60.SCOPUS: ar.jinfo:eu-repo/semantics/publishe