scholarly journals IN VITRO SCREENING FOR ANTHURIUM TOLERANCE TO BURROWING NEMATODE, RADOPHOLUS SIMILIS

HortScience ◽  
1996 ◽  
Vol 31 (3) ◽  
pp. 322d-322
Author(s):  
K.H. Wang ◽  
A.R. Kuehnle ◽  
B. Sipes
Keyword(s):  
Weight Loss ◽  
Genetic Resistance ◽  
Field Evaluation ◽  
Plant Responses ◽  
Radopholus Similis ◽  
Symptom Index ◽  
Plant Weight ◽  
Flower Yield ◽  
Burrowing Nematode

Burrowing nematode, Radopholus similis, reduces flower-yield-infected anthurium fields. Genetic resistance is one alternative to chemical control of the disease in anthurium. Seventeen commercial anthurium varieties, established in vitro on anthurium nutrient medium, were inoculated with burrowing nematodes to screen for tolerance. Three months after inoculation, plant responses were compared by number of nematodes recovered and by symptom index and plant weight loss with respect to non-inoculated plants. Results show that `Mauna Kea' and `Flamingo' anthuriums are among the most tolerant, while `Ozaki' is one of the most susceptible. These results are consistent with grower field evaluation. Nematode count is positively correlated with symptom index and weight loss. The mechanism of tolerance or resistance of anthurium toward burrowing nematode is unclear. However, due to the fact that burrowing nematode is a migratory endoparasite, a preinfectional resistance or tolerance mechanism is more likely to take place.

Host plant response of Eumusa and Australimusa bananas (Musa spp.) to migratory endoparasitic and root-knot nematodes

Nematology ◽  
2000 ◽  
Vol 2 (8) ◽  
pp. 907-916 ◽  
Author(s):  
Ngo Thi Xuyen ◽  
Raf Verlinden ◽  
Ruth Stoffelen ◽  
Dirk De Waele ◽  
Rony Swennen
Keyword(s):  
Host Plant ◽  
Papua New Guinea ◽  
Loamy Sand ◽  
Plant Responses ◽  
Radopholus Similis ◽  
Root Knot Nematodes ◽  
Musa Spp ◽  
Pratylenchus Coffeae ◽  
Meloidogyne Spp

AbstractTwenty-five banana varieties of section Eumusa (AA-group) and seven of the section Australimusa (Fe'i-group) from Papua New Guinea were evaluated for resistance to Radopholus similis, Pratylenchus coffeae and Meloidogyne spp. The host plant responses were compared with the susceptible reference cvs Grande Naine and Cavendish 901. In vitro propagated plants were transferred to the glasshouse in loamy sand and inoculated with approximately 1000 migratory endoparasitic nematodes at 4 weeks after planting. Reproduction of R. similis and P.coffeae in the roots was determined at 8 or 10 weeks, respectively, after inoculation. Reproduction of Meloidogyne spp. was determined 8 weeks after inoculation with 3300 to 5000 eggs. No resistance to R. similis was found in the diploid varieties. The Fe'i variety Rimina and possibly Menei were resistant to R. similis. All varieties tested were susceptible to P.coffeae and Meloidogyne spp. Tests de résistance de bananiers Eumusa et Australimusa (Musa spp.) envers les nématodes endoparasites migrateurs et galligènes - Vingt-cinq variétés de bananier de la section Eumusa (groupe AA) et sept de la section Australimusa (group Fe'i) provenant de Papouasie-Nouvelle Guinée ont été testées pour leur résistance envers Radopholus similis, Pratylenchus coffeae et Meloidogyne spp. Les résponses de ces variétés ont été comparées à celles des cultivars sensibles de référence Grande Naine et Cavendish 901. Des vitroplants ont été mis en place en serre sur un sol argilo-sableux et inoculés 4 semaines après plantation avec environ 1000 R. similis ou P.coffeae dont la reproduction a été déterminée 8 et 10 semaines, respectivement, après inoculation. La reproduction de Meloidogyne spp. l'a été 8 semaines après inoculation avec 3300 à 5000 oeufs. Aucune résistance à R. similis n'a été observée chez les variétés diploïdes. Les variétés du groupe Fe'i Rimina et Menei se sont montrées résistantes à R. similis, avec un certain doute dans le cas de la dernière. Toutes les variétés testées sont sensibles à P.coffeae et Meloidogyne spp.

Attraction and penetration of Musa by the burrowing nematode, Radopholus similis, in an autotrophic bipartite culture system

Nematology ◽  
2021 ◽  
pp. 1-14
Author(s):  
Suganthagunthalam Dhakshinamoorthy ◽  
Erwin J. Galon ◽  
Annemie Elsen ◽  
Dirk De Waele
Keyword(s):  
Culture System ◽  
Model System ◽  
Radopholus Similis ◽  
Susceptible Plant ◽  
Compartment System ◽  
Female Migration ◽  
Equal Distance ◽  
Burrowing Nematode ◽  
Nematode Chemotaxis

Summary Our objective was to discover the stages (pre- or post-infection) in which the resistance to burrowing nematode (Radopholus similis) occurs in two resistant banana (Musa spp.) cultivars. An autotrophic in vitro culture system was used to compare R. similis migration towards, and penetration into, the banana roots. A new two-compartment autotrophic in vitro model system was developed using agar-based medium to examine the migration of R. similis to either the susceptible ‘Grande Naine’ or the resistant ‘Yangambi km5’ (‘Ykm5’), when both the Musa genotypes were present at equal distance. The autotrophic in vitro model system was advantageous, because it supported continuous root growth due to the actively photosynthesising shoots growing in the open air, while the in vitro root conditions make it possible to observe and assess the nematode chemotaxis in the transparent medium. Significantly fewer nematodes migrated towards the resistant ‘Ykm5’ plants when compared to both the susceptible ‘Grande Naine’, and another resistant cultivar, ‘Saba’, at 1 h after infection. This signals a possibility of a lower concentration or different composition of nematode attractants in ‘Ykm5’ root exudates. No significant differences were observed in the percentage of R. similis that migrated towards the roots of the susceptible and resistant banana plants at 3, 4 and 6 h after inoculation. No significant differences were observed in the percentages of female penetration in the resistant and susceptible plant roots at 1 and 2 days after inoculation. The results of the two-compartment system confirmed that when a choice is given to migrate towards the resistant and susceptible genotypes, no differences were observed in the percentage of female migration towards both the genotypes.

Assessment of resistance and tolerance of in vitro-propagated banana plants to burrowing nematode, Radopholus similis

1999 ◽  
Vol 39 (7) ◽  
pp. 891 ◽  
Author(s):  
J. M. Stanton
Keyword(s):  
Life Cycle ◽  
Resistance Mechanism ◽  
Radopholus Similis ◽  
Severe Damage ◽  
Different Ages ◽  
Burrowing Nematode

Summary. In vitro-propagated banana plants cv. Goldfinger were not resistant to Radopholus similis unless they were at least 28 weeks old at inoculation. By contrast, a Pisang jari buaya clone and SH-3142 expressed resistance when inoculated from 12 and 8 weeks of age respectively. Fewer nematodes were recovered from older plants of Goldfinger than from Cavendish 3 weeks after inoculation (i.e. before a life cycle could be completed). This suggests that the resistance mechanism of Goldfinger involves reduction in both penetration and reproduction by nematodes. Comparison of recovery of nematodes following inoculation of plants at different ages showed that resistance assays should use plants which are at least 28 weeks old. Also, plants should be at least 28 weeks old when establishing a plantation to reduce the chance of severe damage by high nematode densities. Goldfinger was more tolerant to R. similis than was Cavendish when supporting the same number of nematodes.

In vitro antagonism of endophytic Fusarium oxysporum isolates against the burrowing nematode Radopholus similis

Nematology ◽  
2006 ◽  
Vol 8 (4) ◽  
pp. 627-636 ◽  
Author(s):  
Bjoern Niere ◽  
Shahasi Athman ◽  
Altus Viljoen ◽  
Clifford Gold ◽  
Thomas Dubois ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Mortality Rates ◽  
Antagonistic Activity ◽  
Radopholus Similis ◽  
Biological Control Agents ◽  
Inhibitory Effects ◽  
Culture Filtrates ◽  
Burrowing Nematode ◽  
Nematode Mortality

AbstractRadopholus similis is one of the key pests of banana worldwide. In this study, nine endophytic Fusarium oxysporum isolates were screened for the production of secondary metabolites antagonistic to R. similis in culture. Undiluted and diluted culture filtrates were tested against motile stages and eggs of R. similis. All isolates tested demonstrated in vitro antagonistic activity, causing paralysis of R. similis motile stages. The percentage of paralysed nematodes increased with increase in the length of exposure time to culture filtrates. After 24 h exposure in culture filtrates up to 100% of the treated nematodes were paralysed compared to 26.5% in the control treatments. Nematode mortality rates after 24 h exposure in culture filtrates ranged from 76.4% to 100%. Paralysis was reversible at lower filtrate concentrations. Radopholus similis males were more sensitive to culture filtrates than females. Culture filtrates of all isolates demonstrated inhibitory effects on hatching of R. similis eggs. The results demonstrate the potential for using endophytic F. oxysporum as biological control agents against R. similis and for toxic derivatives from their secondary metabolism to be used as potential nematicides.

The Potentially Modifiable Risk Factor in Idiopathic Intracranial Hypertension: Body Weight

2021 ◽  
pp. 10.1212/CPJ.0000000000001063
Author(s):  
Susan P Mollan ◽  
Abd A Tahrani ◽  
Alexandra J Sinclair
Keyword(s):  
Weight Loss ◽  
Body Weight ◽  
Risk Factor ◽  
Intracranial Pressure ◽  
Intracranial Hypertension ◽  
Treatment Strategy ◽  
Idiopathic Intracranial Hypertension ◽  
Potential Treatment ◽  
Distal Small Intestine

AbstractPurpose of review:Idiopathic intracranial hypertension (IIH) prevalence increased in conjunction with rising obesity rates. Here, we highlight the importance of weigh management in IIH, and introduce glucagon-like peptide 1 (GLP-1) receptor agonists (RA) as potential treatment strategy for IIH.Recent findings:Weight gain is a risk factor for IIH; and weight loss (via any treatment strategy) plays a key role in IIH management. GLP-1 is an incretin secreted by the distal small intestine in response to a meal. GLP-1 RA have been shown to improve glycaemic control (no. hypoglycaemia) and lower body weight in patients with and without type 2 diabetes. The choroid plexus has been found to express GLP-1 receptors and treatment with a GLP-1 RA significantly reduces cerebrospinal fluid secretion in vitro and intracranial pressure in rodents.Summary:New research evaluating the pathophysiology of IIH supports GLP-1 RA as a potential treatment for IIH via weight loss dependant and independent mechanism to directly reduce intracranial pressure.

scholarly journals The Salt-Stress Response of the Transgenic Plum Line J8-1 and Its Interaction with the Salicylic Acid Biosynthetic Pathway from Mandelonitrile

2018 ◽  
Vol 19 (11) ◽  
pp. 3519 ◽  
Author(s):  
Agustina Bernal-Vicente ◽  
Daniel Cantabella ◽  
Cesar Petri ◽  
José Hernández ◽  
Pedro Diaz-Vivancos
Keyword(s):  
Salicylic Acid ◽  
Salt Stress ◽  
Biosynthetic Pathway ◽  
In Vitro Assays ◽  
Photochemical Quenching ◽  
Plant Responses ◽  
Enzymatic Antioxidants ◽  
Chlorophyll Content And Fluorescence ◽  
Salt Stress Response

Salinity is considered as one of the most important abiotic challenges that affect crop productivity. Plant hormones, including salicylic acid (SA), are key factors in the defence signalling output triggered during plant responses against environmental stresses. We have previously reported in peach a new SA biosynthetic pathway from mandelonitrile (MD), the molecule at the hub of the cyanogenic glucoside turnover in Prunus sp. In this work, we have studied whether this new SA biosynthetic pathway is also present in plum and the possible role this pathway plays in plant plasticity under salinity, focusing on the transgenic plum line J8-1, which displays stress tolerance via an enhanced antioxidant capacity. The SA biosynthesis from MD in non-transgenic and J8-1 micropropagated plum shoots was studied by metabolomics. Then the response of J8-1 to salt stress in presence of MD or Phe (MD precursor) was assayed by measuring: chlorophyll content and fluorescence parameters, stress related hormones, levels of non-enzymatic antioxidants, the expression of two genes coding redox-related proteins, and the content of soluble nutrients. The results from in vitro assays suggest that the SA synthesis from the MD pathway demonstrated in peach is not clearly present in plum, at least under the tested conditions. Nevertheless, in J8-1 NaCl-stressed seedlings, an increase in SA was recorded as a result of the MD treatment, suggesting that MD could be involved in the SA biosynthesis under NaCl stress conditions in plum plants. We have also shown that the plum line J8-1 was tolerant to NaCl under greenhouse conditions, and this response was quite similar in MD-treated plants. Nevertheless, the MD treatment produced an increase in SA, jasmonic acid (JA) and reduced ascorbate (ASC) contents, as well as in the coefficient of non-photochemical quenching (qN) and the gene expression of Non-Expressor of Pathogenesis-Related 1 (NPR1) and thioredoxin H (TrxH) under salinity conditions. This response suggested a crosstalk between different signalling pathways (NPR1/Trx and SA/JA) leading to salinity tolerance in the transgenic plum line J8-1.

scholarly journals Survival of Botrytis cinerea as mycelium in rose crop debris and as sclerotia in soil

2005 ◽  
Vol 30 (5) ◽  
pp. 516-521 ◽  
Author(s):  
Alderi E Araújo ◽  
Luiz A Maffia ◽  
Eduardo S. G Mizubuti ◽  
Acelino C Alfenas ◽  
Guy de Capdeville ◽  
...  
Keyword(s):  
Weight Loss ◽  
Botrytis Cinerea ◽  
Rosa Hybrida ◽  
Inoculum Sources ◽  
Disease Epidemiology ◽  
Plant Parts ◽  
Polyethylene Bags ◽  
Stems And Leaves ◽  
Important Disease

Botrytis blight caused by Botrytis cinerea is an important disease of rose (Rosa hybrida) grown in greenhouses in Brazil. As little is known regarding the disease epidemiology under greenhouse conditions, pathogen survival in crop debris and as sclerotia was evaluated. Polyethylene bags with petals, leaves, or stem sections artificially infected with B. cinerea were mixed with crop debris in rose beds, in a commercial plastic greenhouse. High percentage of plant parts with sporulation was detected until 60 days, then sporulation decreased on petals after 120 days, and sharply decreased on stems or leaves after 90 days. Sporulation on petals continued for 360 days, but was not observed on stems after 150 days or leaves after 240 days. Although the fungus survived longer on petals, stems and leaves are also important inoculum sources because high amounts of both are deposited on beds during cultivation. Survival of sclerotia produced on PDA was also quantified. Sclerotia germination was greater than 75% in the initial 210 days and 50% until 360 days. Sclerotia weight gradually declined but they remained viable for 360 days. Sclerotia were produced on the buried petals, mainly after 90 days of burial, but not on leaves or stems. Germination of these sclerotia gradually decreased after 120 days, but lasted until 360 days. Higher weight loss and lower viability were observed on sclerotia produced on petals than on sclerotia produced in vitro

scholarly journals Decreased TLR3 in Hyperplastic Adipose Tissue, Blood and Inflamed Adipocytes is Related to Metabolic Inflammation

2018 ◽  
Vol 51 (3) ◽  
pp. 1051-1068 ◽  
Author(s):  
Jèssica Latorre ◽  
José M. Moreno-Navarrete ◽  
Mónica Sabater ◽  
Maria Buxo ◽  
José I. Rodriguez-Hermosa ◽  
...  
Keyword(s):  
Weight Loss ◽  
Adipose Tissue ◽  
Low Grade ◽  
Metabolic Inflammation ◽  
Fat Depots ◽  
Acute Surgery ◽  
Obese Subjects ◽  
Anti Inflammatory ◽  
The Impact

Background/Aims: Obesity is characterized by the immune activation that eventually dampens insulin sensitivity and changes metabolism. This study explores the impact of different inflammatory/ anti-inflammatory paradigms on the expression of toll-like receptors (TLR) found in adipocyte cultures, adipose tissue, and blood. Methods: We evaluated by real time PCR the impact of acute surgery stress in vivo (adipose tissue) and macrophages (MCM) in vitro (adipocytes). Weight loss was chosen as an anti-inflammatory model, so TLR were analyzed in fat samples collected before and after bariatric surgery-induced weight loss. Associations with inflammatory and metabolic parameters were analyzed in non-obese and obese subjects, in parallel with gene expression measures taken in blood and isolated adipocytes/ stromal-vascular cells (SVC). Treatments with an agonist of TLR3 were conducted in human adipocyte cultures under normal conditions and upon conditions that simulated the chronic low-grade inflammatory state of obesity. Results: Surgery stress raised TLR1 and TLR8 in subcutaneous (SAT), and TLR2 in SAT and visceral (VAT) adipose tissue, while decreasing VAT TLR3 and TLR4. MCM led to increased TLR2 and diminished TLR3, TLR4, and TLR5 expressions in human adipocytes. The anti-inflammatory impact of weight loss was concomitant with decreased TLR1, TLR3, and TLR8 in SAT. Cross-sectional associations confirmed increased V/ SAT TLR1 and TLR8, and decreased TLR3 in obese patients, as compared with non-obese subjects. As expected, TLR were predominant in SVC and adipocyte precursor cells, even though expression of all of them but TLR8 (very low levels) was also found in ex vivo isolated and in vitro differentiated adipocytes. Among SVC, CD14+ macrophages showed increased TLR1, TLR2, and TLR7, but decreased TLR3 mRNA. The opposite patterns shown for TLR2 and TLR3 in V/ SAT, SVC, and inflamed adipocytes were observed in blood as well, being TLR3 more likely linked to lymphocyte instead of neutrophil counts. On the other hand, decreased TLR3 in adipocytes challenged with MCM dampened lipogenesis and the inflammatory response to Poly(I:C). Conclusion: Functional variations in the expression of TLR found in blood and hypertrophied fat depots, namely decreased TLR3 in lymphocytes and inflamed adipocytes, are linked to metabolic inflammation.

scholarly journals Gamma Interferon Production, but Not Perforin-Mediated Cytolytic Activity, of T Cells Is Required for Prevention of Toxoplasmic Encephalitis in BALB/c Mice Genetically Resistant to the Disease

2004 ◽  
Vol 72 (8) ◽  
pp. 4432-4438 ◽  
Author(s):  
Xisheng Wang ◽  
Hoil Kang ◽  
Takane Kikuchi ◽  
Yasuhiro Suzuki
Keyword(s):  
T Cells ◽  
T Cell ◽  
Nude Mice ◽  
Genetic Resistance ◽  
Cytolytic Activity ◽  
Gamma Interferon ◽  
Toxoplasmic Encephalitis ◽  
Wild Type ◽  
Ifn Γ

ABSTRACT We previously showed the requirement of both T cells and gamma interferon (IFN-γ)-producing non-T cells for the genetic resistance of BALB/c mice to the development of toxoplasmic encephalitis (TE). In order to define the role of IFN-γ production and the perforin-mediated cytotoxicity of T cells in this resistance, we obtained immune T cells from spleens of infected IFN-γ knockout (IFN-γ−/−), perforin knockout (PO), and wild-type BALB/c mice and transferred them into infected and sulfadiazine-treated athymic nude mice, which lack T cells but have IFN-γ-producing non-T cells. Control nude mice that had not received any T cells developed severe TE and died after discontinuation of sulfadiazine treatment due to the reactivation of infection. Animals that had received immune T cells from either wild-type or PO mice did not develop TE and survived. In contrast, nude mice that had received immune T cells from IFN-γ−/− mice developed severe TE and died as early as control nude mice. T cells obtained from the spleens of animals that had received either PO or wild-type T cells produced large amounts of IFN-γ after stimulation with Toxoplasma gondii antigens in vitro. In addition, the amounts of IFN-γ mRNA expressed in the brains of PO T-cell recipients did not differ from those in wild-type T-cell recipients. Furthermore, PO mice did not develop TE after infection, and their IFN-γ production was equivalent to or higher than that of wild-type animals. These results indicate that IFN-γ production, but not perforin-mediated cytotoxic activity, by T cells is required for the prevention of TE in genetically resistant BALB/c mice.

Reproduction of the burrowing nematode (Radopholus similis) on Ri T-DNA transformed carrot roots

Nematology ◽  
2000 ◽  
Vol 2 (2) ◽  
pp. 247-249 ◽  
Author(s):  
Annemie Elsen ◽  
Stéphane Declerck ◽  
Dirk De Waele
Keyword(s):  
Radopholus Similis ◽  
Burrowing Nematode ◽  
Transformed Carrot Roots
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