scholarly journals Responses of Tomato Genotypes to Avirulent and Mi-Virulent Meloidogyne javanica Isolates Occurring in Israel

2014 ◽  
Vol 104 (5) ◽  
pp. 484-496 ◽  
Author(s):  
Ionit Iberkleid ◽  
Rachel Ozalvo ◽  
Lidia Feldman ◽  
Moshe Elbaz ◽  
Bucki Patricia ◽  
...  
Keyword(s):  
Meloidogyne Javanica ◽  
Giant Cells ◽  
Resistant Line ◽  
Tomato Cultivars ◽  
Polymerase Chain ◽  
Mi Gene ◽  
Successive Generations ◽  
Ja Signaling ◽  
First Time ◽  
Avirulent Isolate

The behavior of naturally virulent Meloidogyne isolates toward the tomato resistance gene Mi in major tomato-growing areas in Israel was studied for the first time. Virulence of seven selected isolates was confirmed over three successive generations on resistant (Mi-carrying) and susceptible (non-Mi-carrying) tomato cultivars. Diagnostic markers verified the predominance of Meloidogyne javanica among virulent isolates selected on resistant tomato cultivars or rootstocks. To better understand the determinants of nematode selection on Mi-carrying plants, reproduction of Mi-avirulent and virulent isolates Mjav1 and Mjv2, respectively, measured as eggs per gram of root, on non-Mi-carrying, heterozygous (Mi/mi) and homozygous (Mi/Mi) genotypes was evaluated. Although no reproduction of Mjav1 was observed on Mi/Mi genotypes, some reproduction was consistently observed on Mi/mi plants; reproduction of Mjv2 on the homozygous and heterozygous genotypes was similar to that on susceptible cultivars, suggesting a limited quantitative effect of the Mi gene. Histological examination of giant cells induced by Mi-virulent versus avirulent isolates confirmed the high virulence of Mjv2 on Mi/mi and Mi/Mi genotypes, allowing the formation of well-developed giant-cell systems despite the Mi gene. Analysis of the plant defense response in tomato Mi/Mi, Mi/mi, and mi/mi genotypes to both avirulent and virulent isolates was investigated by quantitative real-time polymerase chain reaction. Although the jasmonate (JA)-signaling pathway was clearly upregulated by avirulent and virulent isolates on the susceptible (not carrying Mi) and heterozygous (Mi/mi) plants, no change in signaling was observed in the homozygous (Mi/Mi) resistant line following incompatible interaction with the avirulent isolate. Thus, similar to infection promoted by the avirulent isolate on the susceptible genotype, the Mi-virulent isolate induced the JA-dependent pathway, which might promote tomato susceptibility during the compatible interaction with the homozygous (Mi/Mi) resistant line. These results have important consequences for the management of Mi resistance genes for ensuring sustainable tomato farming.

scholarly journals A Population of Meloidogyne javanica in Spain Virulent to the Mi Resistance Gene in Tomato

Plant Disease ◽  
2001 ◽  
Vol 85 (3) ◽  
pp. 271-276 ◽  
Author(s):  
C. Ornat ◽  
S. Verdejo-Lucas ◽  
F. J. Sorribas
Keyword(s):  
Population Density ◽  
Negative Correlation ◽  
Meloidogyne Javanica ◽  
Initial Population ◽  
Initial Population Density ◽  
Tomato Yield ◽  
Final Population ◽  
Tomato Cultivars ◽  
Mi Gene ◽  
Susceptible Tomato

A population of Meloidogyne javanica virulent to Mi-gene in tomato was identified in Spain. It reproduced similarly on resistant and susceptible tomato cultivars in the greenhouse, microplots, and in the field. In monoxenic cultures, reproduction of the virulent M. javanica was higher than that of an avirulent population on resistant but not on susceptible tomatoes. The virulent population suppressed tomato yield of both resistant and susceptible tomatoes by 29% in microplots. Initial population density (Pi) was inversely correlated with Pf (final population density)/Pi on both resistant and susceptible tomatoes in the field. A negative correlation was found between Pi and tomato yield for the susceptible but not for the resistant cultivar.

scholarly journals Rickettsia typhi IN RODENTS AND R. felis IN FLEAS IN YUCATÁN AS A POSSIBLE CAUSAL AGENT OF UNDEFINED FEBRILE CASES

2015 ◽  
Vol 57 (2) ◽  
pp. 129-132 ◽  
Author(s):  
Gaspar PENICHE-LARA ◽  
Karla DZUL-ROSADO ◽  
Carlos PÉREZ-OSORIO ◽  
Jorge ZAVALA-CASTRO
Keyword(s):  
Rattus Rattus ◽  
Conventional Polymerase Chain Reaction ◽  
Causal Agent ◽  
Wild Rodents ◽  
Murine Typhus ◽  
Rickettsia Typhi ◽  
Rickettsia Felis ◽  
Vector Borne ◽  
Polymerase Chain ◽  
First Time

Rickettsia typhi is the causal agent of murine typhus; a worldwide zoonotic and vector-borne infectious disease, commonly associated with the presence of domestic and wild rodents. Human cases of murine typhus in the state of Yucatán are frequent. However, there is no evidence of the presence of Rickettsia typhi in mammals or vectors in Yucatán. The presence of Rickettsia in rodents and their ectoparasites was evaluated in a small municipality of Yucatán using the conventional polymerase chain reaction technique and sequencing. The study only identified the presence of Rickettsia typhi in blood samples obtained from Rattus rattus and it reported, for the first time, the presence of R. felis in the flea Polygenis odiosus collected from Ototylomys phyllotis rodent. Additionally, Rickettsia felis was detected in the ectoparasite Ctenocephalides felis fleas parasitizing the wild rodent Peromyscus yucatanicus. This study’s results contributed to a better knowledge of Rickettsia epidemiology in Yucatán.

scholarly journals Jasmonate and Melatonin Act Synergistically to Potentiate Cold Tolerance in Tomato Plants

2022 ◽  
Vol 12 ◽  
Author(s):  
Fei Ding ◽  
Liming Ren ◽  
Fang Xie ◽  
Meiling Wang ◽  
Shuoxin Zhang
Keyword(s):  
Cold Stress ◽  
Cold Tolerance ◽  
Feedback Loop ◽  
Pcr Analysis ◽  
Tomato Plants ◽  
Qrt Pcr ◽  
Cold Condition ◽  
Tomato Cultivars ◽  
Cold Responses ◽  
Ja Signaling

Both jasmonic acid (JA) and melatonin (MT) have been demonstrated to play positive roles in cold tolerance, however, whether and how they crosstalk in the cold responses in plants remain elusive. Here, we report that JA and MT act synergistically in the cold tolerance in tomato plants (Solanum lycopersicum). It was found that JA and MT were both substantially accumulated in response to cold stress and foliar applications of methyl jasmonate (MeJA) and MT promoted cold tolerance as evidenced by increased Fv/Fm, decreased relative electrolyte leakage (EL) and declined H2O2 accumulation in tomato plants. Inhibition of MT biosynthesis attenuated MeJA-induced cold tolerance, while inhibition of JA biosynthesis reduced MT accumulation in tomato plants under cold conditions. Furthermore, qRT-PCR analysis showed that the expressions of two MT biosynthetic genes, SlSNAT and SlAMST, were strongly induced by MeJA, whereas suppression of SlMYC2, a master JA signaling regulator, abated the expressions of SlSNAT and SlAMST under cold stress. Additionally, suppression of SlMYC2 reduced MT accumulation, decreased Fv/Fm and increased EL in cold-stressed tomato plants. Interestingly, exogenous MT promoted JA accumulation, while inhibition of MT biosynthesis significantly reduced JA accumulation in tomato plants under the cold condition. Taken together, these results suggest that JA and MT act cooperatively in cold tolerance and form a positive feedback loop, amplifying the cold responses of tomato plants. Our findings might be translated into the development of cold-resistant tomato cultivars by genetically manipulating JA and MT pathways.

scholarly journals Detection of Toxoplasma gondii in a free-ranging giant anteater

2017 ◽  
Vol 47 (8) ◽  
Author(s):  
Thais Oliveira Morgado ◽  
Francielle Cristina Kagueyama ◽  
Janaina Marcela Assunção Rosa ◽  
Melissa Debesa Belizário ◽  
Richard de Campos Pacheco ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Agglutination Test ◽  
Zoonotic Infection ◽  
Chronic Infections ◽  
Chain Reaction ◽  
Positive Serology ◽  
Modified Agglutination Test ◽  
Polymerase Chain ◽  
Free Ranging ◽  
First Time

ABSTRACT: Toxoplasmosis is caused by Toxoplasma gondii, an obligatory intracellular protozoan, which establishes acute and chronic infections in birds and mammals, including humans. This note reports, for the first time, the detection and sequencing of DNA from T. gondii in the peripheral blood of a young free range giant anteater (Myrmecophaga tridactyla). For the diagnosis, the following methods were used: polymerase chain reaction (PCR) and positive serology (1:800) by means of the modified agglutination test (MAT). Since this species may be consumed by humans and predated by wild felids, its importance is emphasized as a probable source of zoonotic infection, in addition to its possible participation in the infection enzootic cycle. Although, parasitemia has been confirmed in this specimen, it presented no clinical sign of infection.

Agrobacterium-mediated insertional mutagenesis of the ochratoxigenic fungus Aspergillus westerdijkiae

2007 ◽  
Vol 53 (1) ◽  
pp. 148-151 ◽  
Author(s):  
Marcia M Mata ◽  
Marta H Taniwaki ◽  
Beatriz T Iamanaka ◽  
Daniele Sartori ◽  
André L.M Oliveira ◽  
...  
Keyword(s):  
Ochratoxin A ◽  
Insertional Mutagenesis ◽  
Aspergillus Ochraceus ◽  
Agrobacterium Mediated Transformation ◽  
Morphological Variations ◽  
Carcinogenic Potential ◽  
Coffee Beans ◽  
Aspergillus Westerdijkiae ◽  
Polymerase Chain ◽  
First Time

Aspergillus westerdijkiae is a potent ochratoxin A (OTA) producer that has been found in coffee beans. OTA is known to have nephrotoxic effects and carcinogenic potential in animal species. Here we report for the first time the Agrobacterium-mediated transformation for Aspergillus westerdijkiae and the generation of ochratoxin-defective mutants. Conidia were transformed to hygromycin B resistance using strain AGL-1 of Agrobacterium tumefaciens. The obtained transformation frequency was up to 47 transformants per 106 target conidia. Among 600 transformants, approximately 5% showed morphological variations. Eight transformants with consistently reduced OTA production were obtained. Two of these transformants did not produce OTA (detection limit: 0.1 µg/kg); the other six mutants produced lower amounts of OTA (1%–32%) compared with the wild-type strain. By using thermal asymmetric interlaced polymerase chain reaction, we successfully identified a putative flavin adenine dinucleotide monooxygenase gene.Key words: Aspergillus ochraceus, Aspergillus westerdijkiae, Agrobacterium-mediated transformation, Agrobacterium-mediated insertional mutagenesis, ochratoxin A.

Detection of a few DNA copies by real-time electrochemical polymerase chain reaction

The Analyst ◽  
2017 ◽  
Vol 142 (18) ◽  
pp. 3432-3440 ◽  
Author(s):  
M. Moreau ◽  
S. Delile ◽  
A. Sharma ◽  
C. Fave ◽  
A. Perrier ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Real Time ◽  
Current Work ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
First Time ◽  
Accurate Quantification

In the current work, accurate quantification over 10 to 108 DNA copies has been successfully achieved for the first time by real-time electrochemical PCR.

scholarly journals Phylogenetic analysis of Black Bengal and Jamunapari goats in Bangladesh based on partial sequence of cytochrome b gene

2019 ◽  
Vol 17 (1) ◽  
pp. 23-35
Author(s):  
SMZH Chowdhury ◽  
MS Mahmud ◽  
MR Islam ◽  
KHMNH Nazir
Keyword(s):  
Cytochrome B ◽  
Gene Sequence ◽  
Yangtze River Delta ◽  
Climatic Conditions ◽  
Capra Hircus ◽  
Genetic Lineage ◽  
Phylogenetic Status ◽  
Polymerase Chain ◽  
First Time ◽  
Black Bengal Goat

Goats, among the livestock species, are considered the most prolific ruminant especially under callous climatic conditions. The aim of the present study was to depict the current phylogenetic status and genetic diversities of Black Bengal (BBG) and Jamunapari goat of Bangladesh and the world. Cytochrome b (cytb) gene (1140 bp) of mitochondrial DNA of Black Bengal goats (Capra hircus) was amplified by Polymerase Chain Reaction (PCR) for the first time in Bangladesh. The sequence from BBG had no nucleotide (nt) difference and 100% homology with the BBG (C. hircus) of India and also the goats (C. hircus) from China (Yangtze River Delta White Goat), Thailand (Wild Cervidae), Japan (Bezoar goat) and South Africa (Domestic goat). The sequence had 1-5 nt differences and 99% homology with the goats (C. hircus) from China, Thailand and Japan (other goats), and also with the goats (C. hircus) from Malaysia, South Korea, France, Italy, Pakistan, Slovenia, Switzerland and USA. Phylogenetic tree constructed with Black Bengal Goat (BBG-K-2) and Jamunapari goats (SG-1) of Bangladesh with cytochrome b nucleotide sequences were closely related to China-HM7. China-YP xj46, Pakistan-Lineage C1, Pakistan-Lineage C2, Slovenia- ChSo1, Switzerland-ChTo2992 and shared 98.8% to 99% and 98.3% to 98.6% similarity, respectively and 1-1.2% and 1.4 to 1.7% genetic distance, respectively. Based on Ctb gene Sequence collected from Bangladeshi Black Bengal Goats (BBG-K-2) and Jamunapari goats (SG- 1) that were closely related and shared with the same genetic lineage of China HM18 and India-BBG-DQ073048, respectively, suggesting a common origin. SAARC J. Agri., 17(1): 23-35 (2019)

Variation in lipid reserves of second-stage juveniles of Meloidogyne exigua in a coffee field and its relationship with infectivity

Nematology ◽  
2010 ◽  
Vol 12 (3) ◽  
pp. 365-371 ◽  
Author(s):  
Fernando da Silva Rocha ◽  
Jorge Teodoro de Souza ◽  
Vicente Paulo Campos
Keyword(s):  
Image Analysis ◽  
Resistance Gene ◽  
Lipid Content ◽  
Neutral Lipids ◽  
Resistance Level ◽  
Annual Variations ◽  
Second Stage ◽  
Tomato Cultivars ◽  
First Time

AbstractIn this study we assessed the variations in lipid content of second-stage juveniles (J2) of Meloidogyne exigua, recovered from a coffee field, by staining and quantifying the neutral lipids using image analysis. Our results showed that annual variations in J2 stained lipid area correlate with temperature, rainfall and total number of J2 per 100 cm3 of soil. Laboratory and glasshouse experiments showed that decreases in the lipid stained area of J2 of M. exigua led to decreased infectivity and reproduction on tomato. The susceptibility of tomato cvs Kada and Nemadoro to M. exigua varied according to the stained lipid area of the J2 inoculated on roots. Only J2 containing an average of 80% stained lipid area were able to infect cv. Nemadoro, which contains the Mi resistance gene, whereas J2 containing 20% stained lipid area were still able to infect cv. Kada, considered to be highly susceptible. In this study we show for the first time the dynamics of lipid variation in J2 of M. exigua in a coffee field and the dependence of infectivity and parasitism on the resistance level of tomato cultivars and the lipid stained area in J2.

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