New sources of resistance toMeloidogyne incognitarace 3 in wild cotton accessions and histological characterization of the defence mechanisms

Soybean cyst nematode (SCN; Heterodera glycines) continues to be the greatest threat to soybean production in the United States. Since host resistance is the primary strategy used to control SCN, knowledge of SCN virulence phenotypes (HG types) is necessary for choosing sources of resistance for SCN management. To characterize SCN virulence phenotypes in North Dakota (ND), a total of 419 soybean fields across 22 counties were sampled during 2015, 2016, and 2017. SCN was detected in 42% of the fields sampled and population densities in these samples ranged from 30 to 92,800 eggs and juveniles per 100 cm3 of soil. The SCN populations from some of the infested fields were virulence phenotyped with seven soybean indicator lines and a susceptible check (Barnes) using the HG type tests. Overall, 73 SCN field populations were successfully virulence phenotyped. The HG types detected in ND were HG type 0 (frequency rate: 36%), 7 (27%), 2.5.7 (19%), 5.7 (11%), 1.2.5.7 (4%), and 2.7 (2%). However, prior to this study only HG type 0 was detected in ND. The designation of each of the HG types detected was then validated in this study by repeating the HG type tests for thirty-three arbitrarily selected samples. This research for the first time reports several new HG types detected in ND and confirms that the virulence of SCN populations is shifting and overcoming resistance, highlighting the necessity of utilization of different resistance sources, rotation of resistance sources, and identification of novel resistance sources for SCN management in ND.

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Characterization of Colletotrichum lindemuthianum Races in Zambia and Evaluation of the CIAT Phaseolus Core Collection for Resistance to Anthracnose

Plant Disease ◽

10.1094/pdis-02-21-0363-re ◽

2021 ◽

Author(s):

Kelvin Kamfwa ◽

Paul Gepts ◽

Swivia Hamabwe ◽

Zombe Kapata Nalupya ◽

Chikoti Mukuma ◽

...

Keyword(s):

Phaseolus Vulgaris ◽

Common Bean ◽

Core Collection ◽

Durable Resistance ◽

Colletotrichum Lindemuthianum ◽

Sources Of Resistance ◽

Runner Bean ◽

Causal Pathogen ◽

Scarlet Runner Bean

Colletotrichum lindemuthianum, the causal pathogen of common bean (Phaseolus vulgaris) anthracnose, is highly variable. Therefore, understanding its race structure and identification of new sources of resistance is necessary for the development of varieties with durable resistance. The objectives of this study were (i) to characterize isolates of C. lindemuthianum collected from three major bean-growing regions in Zambia, and (ii) evaluate the CIAT Phaseolus core collection for resistance to C. lindemuthianum races 37, 73, and 566, and a blend of 20 races. Isolates collected from three major bean-growing districts in Zambia, namely Mporokoso, Mpika, and Mbala, were characterized as race 37, 73, and 566, respectively. A subset of the CIAT core collection comprised of 885 accessions of common bean, 13 accessions of scarlet runner bean (P. coccineus), and 11 accessions of year bean (P. dumosus) were evaluated for resistance to races 37, 73 and 566, and a blend of 20 races in a greenhouse at University of Zambia, Lusaka, Zambia. A total of 72%, 66%, 48% and 9% of P. vulgaris accessions evaluated were highly resistant to races 37, 73, 566 and a blend of 20 races, respectively. Also, accessions of P. coccineus and P. dumosus, highly resistant to races 37, 73 and 566, were identified. Only eight of the 331 P. vulgaris accessions were highly resistant to all three individual races (37, 73, and 566) and to a blend of 20 races. These eight accessions constitute a valuable breeding resource for developing varieties with durable resistance to C. lindemuthianum.

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Identification and characterization of sources of resistance in Avena sativa, A. byzantina and A. strigosa germplasm against a pathotype of Puccinia coronata f.sp. avenae with virulence against the Pc94 resistance gene

Plant Pathology ◽

10.1111/j.1365-3059.2011.02514.x ◽

2011 ◽

Vol 61 (2) ◽

pp. 315-322 ◽

Cited By ~ 18

Author(s):

J. Sánchez-Martín ◽

D. Rubiales ◽

J. C. Sillero ◽

E. Prats

Keyword(s):

Resistance Gene ◽

Avena Sativa ◽

Puccinia Coronata ◽

Sources Of Resistance ◽

Identification And Characterization

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Isolation and characterization of Bacillus endophytic strains producers for non ribosomal lipopeptides NRLPs from tomato

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v9i1.1209 ◽

2018 ◽

Vol 9 (1) ◽

pp. 128

Author(s):

Walaa Hussein ◽

Ramadan WA ◽

Sameh Fahim

Keyword(s):

High Performance ◽

Plant Defence ◽

Plant Diseases ◽

Bacillus Species ◽

Vegetable Crops ◽

Defence Mechanisms ◽

Isolation And Characterization ◽

Genes Encoding ◽

Plant Defence Mechanisms

Tomato (Solanum lycopersicum) are considered one of the most important vegetable crops and infected by numbers of different diseases. Studying the use of biological alternatives, instead of chemical substances against plant diseases became necessary for the treatment by beneficial microorganisms endophytes, which can excrete natural products benefits to plant in reducing disease severity, promoting growth and inducing plant defence mechanisms. In this work, three endophytes strains were isolated from tomato stems and their 16srDNA have been found to belong to Bacillus species. The first strain was named BMG100, the second BMG101 and the third BMG102. Two Bacillus strains BMG100 and BMG101 have been found to harbour synthetases genes from three lipopeptides families; surfactin, plipastatin, and iturin (mycosubtilin) which can be detected by degenerated primers designed to detect the presence of synthetases genes encoding lipopeptides. The lipopeptides production was proved by their quantification using High Performance Liquid Chromatography (HPLC), whereas BMG100 produced 105, 178 and 293 mg/L of plipastatin, mycosubtilin and surfactin, respectively, BMG101 produced 385 mg/L of surfactin and 236 mg/L of mycosubtilin, while BMG102 showed no lipopeptides production. Keywords: Tomato; Endophytic bacteria; Lipopeptides; Bacillus species

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DdlN from Vancomycin-Producing Amycolatopsis orientalis C329.2 Is a VanA Homologue withd-Alanyl-d-Lactate Ligase Activity

Journal of Bacteriology ◽

10.1128/jb.180.21.5792-5795.1998 ◽

1998 ◽

Vol 180 (21) ◽

pp. 5792-5795 ◽

Cited By ~ 16

Author(s):

C. Gary Marshall ◽

Gerard D. Wright

Keyword(s):

Glycopeptide Antibiotics ◽

Sources Of Resistance ◽

Amycolatopsis Orientalis ◽

Close Relationship ◽

Key Enzyme ◽

Vancomycin Resistant ◽

High Level ◽

Evaluation Of Kinetic Parameters ◽

Level Resistance

ABSTRACT Vancomycin-resistant enterococci acquire high-level resistance to glycopeptide antibiotics through the synthesis of peptidoglycan terminating in d-alanyl-d-lactate. A key enzyme in this process is a d-alanyl-d-alanine ligase homologue, VanA or VanB, which preferentially catalyzes the synthesis of the depsipeptide d-alanyl-d-lactate. We report the overexpression, purification, and enzymatic characterization of DdlN, a VanA and VanB homologue encoded by a gene of the vancomycin-producing organism Amycolatopsis orientalisC329.2. Evaluation of kinetic parameters for the synthesis of peptides and depsipeptides revealed a close relationship between VanA and DdlN in that depsipeptide formation was kinetically preferred at physiologic pH; however, the DdlN enzyme demonstrated a narrower substrate specificity and commensurately increased affinity ford-lactate in the C-terminal position over VanA. The results of these functional experiments also reinforce the results of previous studies that demonstrated that glycopeptide resistance enzymes from glycopeptide-producing bacteria are potential sources of resistance enzymes in clinically relevant bacteria.

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Characterization of sources of resistance to fusarium wilt in chickpea

Indian Phytopathology ◽

10.1007/s42360-020-00242-x ◽

2020 ◽

Vol 73 (4) ◽

pp. 701-705

Author(s):

Archana Shinde ◽

Pawan Kulwal ◽

Ramchandra Perne ◽

Ashok Jadhav

Keyword(s):

Fusarium Wilt ◽

Sources Of Resistance

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Structural and biochemical characterization of the novel serpin Iripin-5 from Ixodes ricinus

Acta Crystallographica Section D Structural Biology ◽

10.1107/s2059798321007920 ◽

2021 ◽

Vol 77 (9) ◽

pp. 1183-1196 ◽

Cited By ~ 2

Author(s):

Barbora Kascakova ◽

Jan Kotal ◽

Larissa Almeida Martins ◽

Zuzana Berankova ◽

Helena Langhansova ◽

...

Keyword(s):

Ixodes Ricinus ◽

Biochemical Characterization ◽

Neutrophil Migration ◽

Stable State ◽

Host Immunity ◽

The Novel ◽

Defence Mechanisms ◽

Reactive Centre Loop ◽

Main Substrate

Iripin-5 is the main Ixodes ricinus salivary serpin, which acts as a modulator of host defence mechanisms by impairing neutrophil migration, suppressing nitric oxide production by macrophages and altering complement functions. Iripin-5 influences host immunity and shows high expression in the salivary glands. Here, the crystal structure of Iripin-5 in the most thermodynamically stable state of serpins is described. In the reactive-centre loop, the main substrate-recognition site of Iripin-5 is likely to be represented by Arg342, which implies the targeting of trypsin-like proteases. Furthermore, a computational structural analysis of selected Iripin-5–protease complexes together with interface analysis revealed the most probable residues of Iripin-5 involved in complex formation.

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Development and characterization of novel wheat-rye 1RS•1BL translocation lines with high resistance to Puccinia striiformis f. sp. tritici

Phytopathology ◽

10.1094/phyto-07-21-0313-r ◽

2022 ◽

Author(s):

Tianheng Ren ◽

Qing Jiang ◽

Zixin Sun ◽

Zhenglong Ren ◽

Feiquan Tan ◽

...

Keyword(s):

Stripe Rust ◽

High Resistance ◽

Puccinia Striiformis ◽

Stripe Rust Resistance ◽

Sources Of Resistance ◽

Chinese Landrace ◽

New Gene ◽

Improvement Programs ◽

Translocation Lines

Wheat-rye 1RS•1BL translocations from Petkus rye have contributed substantially to wheat production worldwide with their great disease resistance and yield traits. However, the resistance genes on the 1RS chromosomes have completely lost their resistance to newly emerged pathogens. Rye could widen the variation of 1RS as a naturally cross-pollinated related species of wheat. In this study, we developed three new 1RS•1BL translocation lines by crossing rye inbred line BL1, selected from Chinese landrace rye Baili, with wheat cultivar Mianyang11. These three new translocation lines exhibited high resistance to the most virulent and frequently occurring stripe rust pathotypes and showed high resistance in the field where stripe rust outbreaks have been most severe in China. One new gene for stripe rust resistance, located on 1RS of the new translocation lines, is tentatively named YrRt1054. YrRt1054 confers resistance to Puccinia striiformis f. sp. tritici pathotypes that are virulent toward Yr9 and YrCn17. This new resistance gene, YrRt1054, is available for wheat improvement programs. The present study indicated that rye cultivars may carry additional untapped variation as potential sources of resistance.

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Characterization of Capsicum chinense Cultigens for Resistance to Meloidogyne arenaria, M. hapla, and M. javanica

Plant Disease ◽

10.1094/pdis.2001.85.3.267 ◽

2001 ◽

Vol 85 (3) ◽

pp. 267-270 ◽

Cited By ~ 4

Author(s):

Judy A. Thies ◽

Richard L. Fery

Keyword(s):

High Resistance ◽

Meloidogyne Incognita ◽

Capsicum Chinense ◽

Sources Of Resistance ◽

Alternative Source ◽

Highly Pathogenic ◽

Habanero Pepper ◽

Race 1 ◽

Race 2

Four Capsicum chinense cultigens with known reactions to Meloidogyne incognita were characterized for resistance to M. arenaria races 1 and 2, M. hapla, and M. javanica, in greenhouse and growth-chamber tests. The M. incognita-resistant cultigens PA-353, PA-398, and PA-426 exhibited high resistance to M. arenaria race 1; the M. incognita-susceptible PA-350 was susceptible to M. arenaria race 1. M. arenaria race 2 and M. javanica were not highly pathogenic to any of the C. chinense cultigens. PA-353, PA-398, and PA-426, however, supported an average of 98.1 and 94.8% fewer (P < 0.05) M. arenaria race 2 and M. javanica eggs per gram fresh root, respectively, than PA-350. M. hapla was pathogenic to all four C. chinense cultigens. PA-353, PA-398, and PA-426 will be useful sources of resistance to M. arenaria races 1 and 2, M. javanica, and M. incognita, for developing resistant habanero pepper cultivars; however, an alternative source of resistance must be identified for M. hapla.

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