Screening of chemical attractants for second‐stage juveniles of meloidogyne species on agar plates

2020 ◽  
Author(s):  
Yuji Oka
Keyword(s):  
Second Stage ◽  
Chemical Attractants ◽  
Meloidogyne Species

Nematostatic activity of aqueous extracts of West African Crotalaria species

Nematology ◽  
2004 ◽  
Vol 6 (5) ◽  
pp. 765-771 ◽  
Author(s):  
Philippe Jourand ◽  
Thierry Mateille ◽  
Mireille Fargette ◽  
Sylvie Rapior
Keyword(s):  
Multivariate Analysis ◽  
Meloidogyne Incognita ◽  
Plant Tissue ◽  
Green Manure ◽  
West African ◽  
Aqueous Extracts ◽  
Root Extracts ◽  
Second Stage ◽  
Meloidogyne Species

AbstractThe in vitro paralysis of second-stage juveniles of Meloidogyne incognita, M. javanica and M. mayaguensis by aqueous extracts of 15 West African Crotalaria species was analysed. A multivariate analysis distinguished four groups, based on their nematostatic activity: i) C. glaucoides extracts were not active; ii) the root extracts from C. goreensis, C. lathyroides and C. perrottetii were more active than the shoot extracts; iii) the shoot extracts from C. comosa and C. cylindrocarpa were more active than the root extracts; iv) both shoot and root extracts of C. atrorubens, C. barkae, C. grantiana, C. hyssopifolia, C. pallida, C. podocarpa, C. retusa, C. senegalensis and C. sphaerocarpa have nematostatic effects depending on either the Crotalaria species or plant tissue from which the extracts were derived. However, considering the greater biomass contribution of the leaves and stems compared to the roots when the plants are used as green manure, C. barkae, C. grantiana, C. pallida and C. podocarpa are the most efficient Crotalaria species, whatever the Meloidogyne species targeted.

scholarly journals The Use of Essential Oil and Hydrosol Extracted from Satureja hellenica for the Control of Meloidogyne incognita and M. javanica

Plants ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 856
Author(s):  
Iro Pardavella ◽  
Eleni Nasiou ◽  
Dimitra Daferera ◽  
Panayiotis Trigas ◽  
Ioannis Giannakou
Keyword(s):  
Essential Oil ◽  
Plant Species ◽  
Meloidogyne Incognita ◽  
Major Constituent ◽  
Infested Soil ◽  
Second Stage ◽  
Indigenous Plant ◽  
Meloidogyne Species

Essential oil (EO) and hydrosol (HL) isolated from an indigenous plant species Satureja hellenica were evaluated against Meloidogyne incognita and M. javanica. Particularly, the activity of extracts on a second stage juvenile’s (J2s) motility, the hatching of J2s from eggs, egg differentiation and the effect on J2s in soil were tested. A paralysis of 100% of the J2s of both species was recorded after 96 h of immersion in the essential oil, at a dose of 2000 μL/L. At the same dose, the percentage of paralyzed J2s after 48 h of immersion was more than 80%, for both Meloidogyne species. The use of hydrosol has shown encouraging results only in the dilution of 50%, where for both Meloidogyne species tested, the percentage of paralyzed J2s was more than 70% after 48 h of immersion, while the percentage was increased to 90% after 96 h of immersion. Egg differentiation was ceased after immersion, either in EO or HL. However, this decrease in egg differentiation was evident only at higher concentrations of EO and at the highest HL dilution (0.5 v/v). The hatching of M. incognita J2s was decreasing as the dose was increasing. The lowest numbers of hatched J2s were recorded at the doses of 2000 and 4000 μL/L. A clear reduction in M. javanica J2s hatching was observed as the dose was increased to 250 μL/L, a fact constantly observed as the dose was increasing up to 4000 μL/L. Lower numbers of nematodes were recorded in roots grown in infested soil after the application of EO or HL at the highest doses. The EO of S. hellenica is characterized by the presence of p-cymene (27.46%) and carvacrol (23.25%), and in a lesser extent of other constituents, such as borneol (6.79%), carvacrol methylether (6.77%), γ-terpinene (4.63%) and 4-terpineol (3.65%). Carvacrol was the major constituent found in the HL (50.12%), followed by borneol and 4-terpineol (20.42 and 6.72%, respectively).

Additional notes on the morphology of Meloidogyne spartinae (Nematoda: Meloidogynidae)

Nematology ◽  
2001 ◽  
Vol 3 (4) ◽  
pp. 303-312 ◽  
Author(s):  
Hedwig Hirschmann ◽  
Jonathan Eisenback
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
The Other ◽  
Ancestral Form ◽  
Second Stage ◽  
Meloidogyne Species ◽  
Scanning Electron

AbstractFemales, males and second-stage juveniles of Meloidogyne spartinae were examined by light and scanning electron microscopy. The morphology of M. spartinae is very typical of the genus for most characters in general. However, as expected, some minor differences occur, particularly in the shape of the head, stylet and tail, and morphometrics of several characters. It is not clear at present how the karyotype of seven chromosomes in M. spartinae is related to the 13-18 chromosomes of other apparently related Meloidogyne species. The M. spartinae karyotype may represent an ancestral form from which the other species have evolved, possibly as polyploid-aneuploids. More studies are needed to clarify this point. However, M. spartinae is remarkably similar in morphology to other species and is justly placed within the genus Meloidogyne.

The Use of Second-Stage Juvenile Tails as an Aid in the Identification of Meloidogyne Species

Nematologica ◽  
1983 ◽  
Vol 29 (1) ◽  
pp. 11-28 ◽  
Author(s):  
Susan B. Jepson
Keyword(s):  
Second Stage ◽  
Stage Juvenile ◽  
Meloidogyne Species

scholarly journals The Use of Essential Oil and Hydrosol Extracted from Cuminum cyminum Seeds for the Control of Meloidogyne incognita and Meloidogyne javanica

Plants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 46
Author(s):  
Iro Pardavella ◽  
Demetra Daferera ◽  
Theodoros Tselios ◽  
Panagiota Skiada ◽  
Ioannis Giannakou
Keyword(s):  
Essential Oil ◽  
Meloidogyne Incognita ◽  
Meloidogyne Javanica ◽  
Root Knot Nematode ◽  
Root Knot Nematodes ◽  
Cuminum Cyminum ◽  
Clear Effect ◽  
Second Stage ◽  
Low Concentrations ◽  
Meloidogyne Species

The essential oil (EO) and hydrosol (HL) isolated from Cuminum cyminum (cumin) seeds were evaluated against the root-knot nematodes Meloidogyne incognita and M. javanica. The efficacy of extracts on the motility, hatching, and survival in soil of second-stage juveniles (J2s), and the activity on egg differentiation were tested. All J2s were paralyzed after immersion in the EO at 62.5 μL/L concentration for 96 h. Encouraging results were recorded using HL equal to or higher than 10% concentration for both Meloidogyne species tested. More than 70% paralyzed J2s were recorded after immersion for 48 h, while the percentage was increased to higher than 90% after 96 h of immersion. A clear effect on egg differentiation was observed after immersion in EO or HL. A significant decrease in egg differentiation was revealed at even low concentrations of EO while an evident decrease in egg differentiation was recorded after immersion of eggs in 50% HL dilution. Decreased hatching of M. incognita and M. javanica J2s was observed with the increase in concentration. The lowest numbers of hatched J2s were recorded when EO was used at 1000 and 2000 μL/L concentrations. A constant reduction in root-knot nematode J2 hatching was observed upon increasing the concentration of HL from 5% to 50%. The EO of C. cyminum is characterized by the presence of γ-terpinene-7-al (34.95%), cumin aldehydes (26.48), and α-terpinene-7-al (12.77%). The above constituents were observed in HL following the same order as that observed in EO. The components γ-terpinene (11.09%) and ο-cymene (6.56%) were also recorded in EO while they were absent in HL.

Altered Fine Structure of B Lymphocytes Correlated with Defective Terminal Differentiation

1973 ◽  
Vol 31 ◽  
pp. 386-387
Author(s):  
Dale E. Bockman ◽  
L. Y. Frank Wu ◽  
Alexander R. Lawton ◽  
Max D. Cooper
Keyword(s):  
Immune Deficiency ◽  
B Lymphocytes ◽  
Plasma Cells ◽  
Present Report ◽  
Specific Antigen ◽  
Terminal Differentiation ◽  
Second Stage ◽  
Two Stages ◽  
Deficiency Diseases ◽  
Cell Line Generation

B-lymphocytes normally synthesize small amounts of immunoglobulin, some of which is incorporated into the cell membrane where it serves as receptor of antigen. These cells, on contact with specific antigen, proliferate and differentiate to plasma cells which synthesize and secrete large quantities of immunoglobulin. The two stages of differentiation of this cell line (generation of B-lymphocytes and antigen-driven maturation to plasma cells) are clearly separable during ontogeny and in some immune deficiency diseases. The present report describes morphologic aberrations of B-lymphocytes in two diseases in which second stage differentiation is defective.

Cryomicroscopy of multiphase latices

1991 ◽  
Vol 49 ◽  
pp. 1060-1061
Author(s):  
O. L. Shaffer ◽  
M.S. El-Aasser ◽  
C. L. Zhao ◽  
M. A. Winnik ◽  
R. R. Shivers
Keyword(s):  
Electron Microscopy ◽  
Radiation Damage ◽  
Freeze Fracture ◽  
Particle Morphology ◽  
Second Stage ◽  
Transmission Electron ◽  
Important Approach ◽  
Carbon Coated ◽  
Preparation Techniques

Transmission electron microscopy is an important approach to the characterization of the morphology of multiphase latices. Various sample preparation techniques have been applied to multiphase latices such as OsO4, RuO4 and CsOH stains to distinguish the polymer phases or domains. Radiation damage by an electron beam of latices imbedded in ice has also been used as a technique to study particle morphology. Further studies have been developed in the use of freeze-fracture and the effect of differential radiation damage at liquid nitrogen temperatures of the latex particles embedded in ice and not embedded.Two different series of two-stage latices were prepared with (1) a poly(methyl methacrylate) (PMMA) seed and poly(styrene) (PS) second stage; (2) a PS seed and PMMA second stage. Both series have varying amounts of second-stage monomer which was added to the seed latex semicontinuously. A drop of diluted latex was placed on a 200-mesh Formvar-carbon coated copper grid.

Observations on the growth of barium bismuth oxide thin films

1992 ◽  
Vol 50 (1) ◽  
pp. 76-77
Author(s):  
M G. Norton ◽  
E.S. Hellman ◽  
E.H. Hartford ◽  
C.B. Carter
Keyword(s):  
Substrate Temperature ◽  
Deposition Process ◽  
Nucleation Layer ◽  
Second Stage ◽  
Device Applications ◽  
High Transition ◽  
Substrate Temperatures ◽  
Oriented Material ◽  
Barium Bismuth ◽  
Superconductor Device

The bismuthates (for example, Ba1-xKxBiO3) represent a class of high transition temperature superconductors. The lack of anisotropy and the long coherence length of the bismuthates makes them technologically interesting for superconductor device applications. To obtain (100) oriented Ba1-xKxBiO3 films on (100) oriented MgO, a two-stage deposition process is utilized. In the first stage the films are nucleated at higher substrate temperatures, without the potassium. This process appears to facilitate the formation of the perovskite (100) orientation on (100) MgO. This nucleation layer is typically between 10 and 50 nm thick. In the second stage, the substrate temperature is reduced and the Ba1-xKxBiO3 is grown. Continued growth of (100) oriented material is possible at the lower substrate temperature.

Second stage of labor in the age of epidural anesthesia

1998 ◽  
Vol 5 (1) ◽  
pp. 171A-171A
Author(s):  
E XENAKIS ◽  
J PIPER ◽  
M MCFARLAND ◽  
C SUITER ◽  
O LANGER
Keyword(s):  
Epidural Anesthesia ◽  
Second Stage Of Labor ◽  
Second Stage
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