Ancy Salim M
Bioherbicidal potential of fungal pathogenes of water hyacinth [Eichhornia crassipes (Mart.) Solms] - Vellayani Department of Plant Pathology, College of Agriculture 2003
The study entitled "Bioherbicidal potential of fungal pathogens of
water hyacinth [Eichhornia crassipes (Mart.) Solrns]", was conducted at
College of Agriculture, Vellayani, Thiruvananthapuram during 2001-2003.
Fourteen pathogenic fungi of water hyacinth obtained from the
survey conducted as a part of the DST project on "Biocontro l of water
hyacinth using mycoherbicides" were used for the study. Fungi which were
not identified earlier were characterized and identified based on the cultural
and morphological characters and was confirmed by sending to Agharkar
Research Institute, Pune. These three fungi viz., Bipolaris tetramera,
Drechslera sp. and Pestalotiopsis guepinii, were new records on water
hyacinth.
The fungi varied in the symptom development on water hyacinth
with respect to nature of symptoms, parts affected and the time taken for
the symptom development. The intensity of infection by the fungi varied
from 9.94 to 58.80 per cent. Only five fungi viz., A.eichhorniae,
F. moniliforme, F. oxysporum (isolate 2), F. pallidoroseum (isolate 3) and
I
M. advena gave more than 45 per cent intensity of infection.
Cell free metabolites of the various fungi also varied in the symptom
development. Intensity of damage varied from 8.03 to 89.00 per cent.
Maximum was recorded by M. advena followed by F. pallidoroseum
(49.80 per cent), A. eichhorniae (48.80 per cent) and F. oxysporum (47.20
per cent).
Host range of A. eichhorniae, F. moniliforme and F. oxysporum was
studied in detail. A. eichhorniae infected only three weed plants out of the
37 cultivated and 39 weed plants tested. F. moniliforme infected five
11
cultivated and 11 weed plants. F. oxysporum was found to be pathogenic
to seven cultivated and nine weed plants.
Combined application of A. eichhorniae and F. p allidorose um
recorded higher intensity of infection than when sprayed alone.
A. eichhorniae was found to give effective destruction of the weed at 107
spores per ml concentration. A. eichhorniae at 107 spores per ml and
F. p all idoroseum at lOll spores per ml together recorded more intensity of
infection of 89.84 per cent than when sprayed alone.
Talc based combination product of A. eichhorniae and F. pallidoroseum
when sprayed at 10.00 per cent concentration recorded an intensity of
infection of 93.20 per cent, 10 days after spraying. The formulated product
could retain the viability of spores of the pathogens at room temperature
for 15 days.
632.3 / ANC/BI
Bioherbicidal potential of fungal pathogenes of water hyacinth [Eichhornia crassipes (Mart.) Solms] - Vellayani Department of Plant Pathology, College of Agriculture 2003
The study entitled "Bioherbicidal potential of fungal pathogens of
water hyacinth [Eichhornia crassipes (Mart.) Solrns]", was conducted at
College of Agriculture, Vellayani, Thiruvananthapuram during 2001-2003.
Fourteen pathogenic fungi of water hyacinth obtained from the
survey conducted as a part of the DST project on "Biocontro l of water
hyacinth using mycoherbicides" were used for the study. Fungi which were
not identified earlier were characterized and identified based on the cultural
and morphological characters and was confirmed by sending to Agharkar
Research Institute, Pune. These three fungi viz., Bipolaris tetramera,
Drechslera sp. and Pestalotiopsis guepinii, were new records on water
hyacinth.
The fungi varied in the symptom development on water hyacinth
with respect to nature of symptoms, parts affected and the time taken for
the symptom development. The intensity of infection by the fungi varied
from 9.94 to 58.80 per cent. Only five fungi viz., A.eichhorniae,
F. moniliforme, F. oxysporum (isolate 2), F. pallidoroseum (isolate 3) and
I
M. advena gave more than 45 per cent intensity of infection.
Cell free metabolites of the various fungi also varied in the symptom
development. Intensity of damage varied from 8.03 to 89.00 per cent.
Maximum was recorded by M. advena followed by F. pallidoroseum
(49.80 per cent), A. eichhorniae (48.80 per cent) and F. oxysporum (47.20
per cent).
Host range of A. eichhorniae, F. moniliforme and F. oxysporum was
studied in detail. A. eichhorniae infected only three weed plants out of the
37 cultivated and 39 weed plants tested. F. moniliforme infected five
11
cultivated and 11 weed plants. F. oxysporum was found to be pathogenic
to seven cultivated and nine weed plants.
Combined application of A. eichhorniae and F. p allidorose um
recorded higher intensity of infection than when sprayed alone.
A. eichhorniae was found to give effective destruction of the weed at 107
spores per ml concentration. A. eichhorniae at 107 spores per ml and
F. p all idoroseum at lOll spores per ml together recorded more intensity of
infection of 89.84 per cent than when sprayed alone.
Talc based combination product of A. eichhorniae and F. pallidoroseum
when sprayed at 10.00 per cent concentration recorded an intensity of
infection of 93.20 per cent, 10 days after spraying. The formulated product
could retain the viability of spores of the pathogens at room temperature
for 15 days.
632.3 / ANC/BI