נגישות
menu      
חיפוש מתקדם
תחביר
חפש...
הספר "אוצר וולקני"
אודות
תנאי שימוש
ניהול
קהילה:
אסיף מאגר המחקר החקלאי
פותח על ידי קלירמאש פתרונות בע"מ -
Biocontrol of root-knot nematodes by Trichoderma – modes of action
Year:
2009
Source of publication :
IOBC/WPRS Bulletin
Authors :
בר-אייל, מאירה
;
.
שפיגל, יצחק
;
.
שרון, עדנה
;
.
Volume :
42
Co-Authors:

Ilan Chet

Facilitators :
From page:
159
To page:
163
(
Total pages:
5
)
Abstract:

Isolates of Trichoderma asperellum (T 203, T 44, T GH11), T. atroviride IMI206040 and
T. harzianum 248 exhibited biocontrol activity against Meloidogyne javanica in soil experiments.
Parasitic interactions were demonstrated in planta: females and egg masses dissected from tomato
roots grown in T203-treated soil were found to be parasitized by the fungus. Trichoderma that
colonizes the root surface may also interact with penetrating second-stage juveniles (J2s). Conidia
attachment and parasitism of fungi on the nematode were examined in vitro: egg masses, their derived
eggs and second-stage juveniles (J2) were parasitized by T. asperellum 203, 44, and T. atroviride
following conidia attachment. T. asperellum GH11 attached to the nematodes but exhibited reduced
penetration, whereas growth of T. harzianum 248 attached to egg masses was inhibited. Only few
conidia of the different fungi were attached to eggs and J2s without gelatinous matrix; the eggs were
penetrated and parasitized by few hyphae, while J2s were rarely parasitized by the fungi. Coiling and
appressorium-like structures were observed during parasitism. Gelatinous matrix suspension
agglutinated T. asperellum 203 and T. atroviride conidia, a process that was Ca2+ dependent. Conidia
agglutination was reduced by carbohydrates, including fucose, as was conidia attachment to the
nematodes. Fucose-specific antibody and lectin enhanced conidia attachment to the nematodes,
suggesting the involvement of carbohydrate-lectin based interactions, in the attachment process. All
but T. harzianum could grow on the gelatinous matrix, which enhanced conidia germination. A
biomimetic system based on gelatinous-matrix-coated nylon fibers demonstrated the role of the matrix
in parasitism. T. asperellum 203, 44 and T. atroviride produced metabolites that immobilized J2s in
the presence of the matrix. Trichoderma proteolytic and chitinolytic activities were also induced
during nematode parasitism. Indirect interactions potentially involving systemic induced resistance
mechanisms were demonstrated on split root systems with T 203: significant reductions in root
penetration, galling indices, egg production and nematode development inhibition were recorded in the
root halves that were not directly treated with Trichoderma.

Note:
Related Files :
antibody
BioControl
chitinolytic and proteolytic enzymes
Gelatinous matrix
lectin
Meloidogyne javanica
Parasitism
Root-knot nematodes
עוד תגיות
תוכן קשור
More details
DOI :
Article number:
0
Affiliations:
Database:
גוגל סקולר
Publication Type:
מאמר מתוך כינוס
;
.
Language:
אנגלית
Editors' remarks:
ID:
38943
Last updated date:
02/03/2022 17:27
Creation date:
10/01/2019 08:14
Scientific Publication
Biocontrol of root-knot nematodes by Trichoderma – modes of action
42

Ilan Chet

Biocontrol of root-knot nematodes by Trichoderma – modes of action

Isolates of Trichoderma asperellum (T 203, T 44, T GH11), T. atroviride IMI206040 and
T. harzianum 248 exhibited biocontrol activity against Meloidogyne javanica in soil experiments.
Parasitic interactions were demonstrated in planta: females and egg masses dissected from tomato
roots grown in T203-treated soil were found to be parasitized by the fungus. Trichoderma that
colonizes the root surface may also interact with penetrating second-stage juveniles (J2s). Conidia
attachment and parasitism of fungi on the nematode were examined in vitro: egg masses, their derived
eggs and second-stage juveniles (J2) were parasitized by T. asperellum 203, 44, and T. atroviride
following conidia attachment. T. asperellum GH11 attached to the nematodes but exhibited reduced
penetration, whereas growth of T. harzianum 248 attached to egg masses was inhibited. Only few
conidia of the different fungi were attached to eggs and J2s without gelatinous matrix; the eggs were
penetrated and parasitized by few hyphae, while J2s were rarely parasitized by the fungi. Coiling and
appressorium-like structures were observed during parasitism. Gelatinous matrix suspension
agglutinated T. asperellum 203 and T. atroviride conidia, a process that was Ca2+ dependent. Conidia
agglutination was reduced by carbohydrates, including fucose, as was conidia attachment to the
nematodes. Fucose-specific antibody and lectin enhanced conidia attachment to the nematodes,
suggesting the involvement of carbohydrate-lectin based interactions, in the attachment process. All
but T. harzianum could grow on the gelatinous matrix, which enhanced conidia germination. A
biomimetic system based on gelatinous-matrix-coated nylon fibers demonstrated the role of the matrix
in parasitism. T. asperellum 203, 44 and T. atroviride produced metabolites that immobilized J2s in
the presence of the matrix. Trichoderma proteolytic and chitinolytic activities were also induced
during nematode parasitism. Indirect interactions potentially involving systemic induced resistance
mechanisms were demonstrated on split root systems with T 203: significant reductions in root
penetration, galling indices, egg production and nematode development inhibition were recorded in the
root halves that were not directly treated with Trichoderma.

Scientific Publication
You may also be interested in