BIOEFFICACY OF HEXACONAZOLE 5 SC AGAINST RICE SHEATH BLIGHT (Rhizoctonia so/ani

200 Pages·2002·5.93 MB·English

BIOEFFICACY OF HEXACONAZOLE 5 SC AGAINST RICE SHEATH
BLIGHT (Rhizoctonia so/ani Kuhn) AND GROUND NUT LATE LEAF
SPOT (Phaeoisariopsis personata (Berk and Curt.) V. Arx), IT'S
PERSISTENCE AND RESIDUES
Thesis submitted in part fulfilment of the requirements for the degree of DOCTOR
OF PHILOSOPHY (AGRICULTURE) in PLANT PATHOLOGY to the
TAMIL NADU AGRICULTURAL UNIVERSITY
Coimbatore 641 003.
by
I. JOHNSON
(I. D. No. 98-812-002)
DEPARTMENT OF PLANT PATHOLOGY
CENTRE FOR PLANT PROTECTION STUDIES
TAMIL NADU AGRICULTURAL UNIVERSITY
COIMBATORE 641 003.
2001
CERTIFICATE
This is to certify that the thesis entitled "BIOEFFICACY OF HEXACONAZOLE
5 SC AGAINST RICE SHEATH BLIGHT (Rhizoctonia solani Kuhn) AND
GROUNDNUT LATE LEAF SPOT (Phaeoisariopsis personata (Berk and Curt.) V.
Arx), I'rS PERSISTENCE AND RESIDUES" submitted in part fulfilment of the
requirements for the award of the degree of DOCTOR OF PHILOSOPHY
(AGRICULTURE) in PLANT PATHOLOGY to the Tamil Nadu Agricultural University,
Coimbatore, is a record of bonafide research work carried out by Mr. I. JOHNSON under
my supervision and guidance and that no part of this thesis has been submitted for the
award of any other degree, diploma, fellowship or other similar titles or prizes and that the
work has not been published in part or full in any scientific or popular jfmal or magaZin.e.
~
Place: Coimbatore-3 . .
Date: 09. 11.2001 (Dr. T. MARIMUT
Chairman
Approved by
~
Chairman:
MARI~
. (Dr. T. UMU~
~
Members:
(Dr. R. SAMIY APPAN)
Acknowledgement
ACKNOWLEDGEMENT
Happiness is the cream of life which I attained through the immaculate guidance
of my chairman Prof. T. Marimuthu, Ph.D, Dean (PGS), TNAU, Coimbatore who's
unstinted and scintillating support throughout the investigation deserves me to outcome
my bountiful thanks.
From the bottom of my heart, with a deep sense of gratitude, lowe my debts of
thanks to the members of advisory committee, Dr. R. Samiyappan, Professor,
Department of Plant Pathology, Dr. T. M. Thiyagarajan, Director (SCMS) and
Dr. S. KuttaJam, Professor, Department of Agricultural Entomology. Their beacon like
help throughout the study can not be acknowledged implicitly.
I have boundless pleasure in expressing my gratefulness and thanks to
Dr. Sabitha Doraiswamy, Director (CPPS), Dr. G. Ramakrishnan, Professor and
Head, Department of Plant Pathology and all other Professors, Associate Professors and
Assistant Professors for their constant encouragement throughout the course of study.
Words are ineffable to pay my heartfelt and inexplicable gratitude to
Dr. D. Packiaraj, Associate Professor and Head, ARS, Aliyar Nagar, Dr. J. Sheela,
Dr. V. Jayalakshmi, and Dr. K. Rajamanickam, Assistant Professors, Rajalakshmi
and Rukkia labours ARS, Aliyar Nagar for their titanic help during field trials and
Dr. S. Chandrasekar, Associate Professor, Department of Agricultural Entomology for
his help during the crucial time of needs in residue analysis.
I am immensely delighted to convey my thanks to Dr. V. Prakasam, Professor,
Dr. A.S. Krishfiamoorthy, Dr. -T. ~ Raguchander, Dr. K. Prabhakar,
Dr. S. Nakkeeran, Dr. K. Angappan, Dr. Karthikeyan, Dr. A. Ramanathan, and
Mr. A. Kamalakannan, Assistant Professors, Department of Plant Pathology,
Mr. Balamuralikrishnan, Scientist, Cannanore, for their incredible and unending
benevolence in bringing this work fruitfully.
It is of paramount importance to thank the innovative minds Dr. S. Babu,
Dr. K. Kumar, Miss. G. Amutha and Mr. M. Loganathan for their ingenious,
constructive criticism and constant encouragement throughout the research programme.
As said, "Dearest is the friend's love" who's volunteered help at the time of need
for achieving my cherished goal pave me to offer my loveable and debted thanks to my
comrades Sible, Kannz, Radjacommare, Kannan, Deborah, Samuthira, Viji, Latha,
Geetha, Senthil, junior and senior colleagues of my department, Senthil, Somu, Gaja,
Anbazhagan, Anandakrishnan, Janaki, Ragu, Rama, Suresh, Shanmuga Sundaram
of other Departments.
My earnest regards are extended to Jaisankar, Mahendren and Kasi who helped
me a lot during my study period.
My classmates Nanda, Mike, Kalps, Mano, Rams, Vasanthi, Dr. Dcvji
Assistant Professor, Tirur and Mr. Thangavelu Scientist, NRCB, Trichy deserve
bountiful love and thanks for their artless attention and care towards me.
On a personal note, lowe my debt of gratitude to my parents, brother Nelson and
my confidant Arul Chezhian who have laid out the foundation for my successful
educational career and the great source of encouragement, sacrifice and the inexhaustible
love without whom I would not have completed this thesis.
I thank Zeneca Agrochemicals Ltd, Chennai for having sponsored Senior
Research Fellowship to undergo my research programme.
Finally, I express my commitment to the Tamil Nadu Agricultural University,
Coimbatore for letting my dreams come true.
Abstract
ABSTRACT
BIOEFFICACY OF HEXACONAZOLE 5 SC AGAINST RICE SHEATH BLIGHT
(Rhizoctol1ia solani KUhn) AND GROUNDNUT LATE LEAF SPOT (Phaeoisariopsis
personata (Berk and Curt.) V. Arx), IT'S PERSISTENCE AND RESIDUES
By
I. JOHNSON
DEGREE : DOCTOR OF PHILOSOPHY (AGRICULTURE)
PLANT PATHOLOGY
CHAIRMAN : PROF. T. MARIMUTHU, Ph.D.
DEAN (POST GRADUATE STUDIES)
TAMIL NADU AGRICULTURAL UNIVERSITY
COIMBATORE 641003
2001
Studies were carried out to evaluate the bioefficacy of hexaconazole 5 SC
against rice sheath blight (Rhizoctonia solani KUhn) and groundnut late leaf spot
" ~/
v.
(Phaeoisariopsis personata (Berk and Cilrt.) Arx) diseases. Persistence of the
fungicide, its compatibility with insecticides and biocontrol agents, safety to
parasitoids and predators, non target effect on phylloplane and rhizosphere microbial
population, role in induced systemic resistance, effect on plant constituents and harvest
time residues in crop and soil were studied.
Hexaconazole at different doses (500, 1000, 1500 and 2000 ml ha-I) was highly
effective against rice sheath blight and groundnut late leaf spot diseases in three field
trials and two green house trials. The efficacy also increased with increase in the
dosage of fungicide. Hexaconazole was compatible with insecticides viz.,
monocrotophos, chlorpyriphos and showed synergistic action against pests and disease
of rice and groundnut. At higher concentration (2000 ml ha-I hexaconazole persisted
)
up to seven days and at lower concentration (500 ml ha-I persisted up to five days after
)
last spraying in both the crops. There was no phytotoxic effect even at higher
concentration of the chemical.
The compatibility studies of hexaconazole with biocontrol agents revealed that
it was highly inhibitory to the fungal antagonists, Trichoderma viride, T. harzianum
and Gliocladium virens even at low concentration (0.5 ppm). However, the growth and
development of bacterial antagonists viz., Pseudomonas fluorescens and Bacillus
subtilis remained unaffected. Hexaconazole was also found to be safe to the beneficial
insects such as the egg parasitoid, Trichogramma chilonis and Chrysoperla carnea.
Spraying of hexaconazole resulted in initial reduction of the phylloplane fungal
and bacterial popul~tion which later increased on fifth day after spraying. Similarly, the
-
rhizosphere microbial population also reduced on first day and started increasing there
after.
Induction of peroxidase activity in groundnut was observed immediately after
spraying of hexaconazole. Apart from the defense enzymes, increase in chlorophyll,
soluble protein, phenol contents and nitrate reductase activity were observed in the
leaves of rice and groundnut. However, there was no change in carbohydrate and
protein contents of rice grains and groundnut kernels.
Hexaconazole was highly inhibitory to other pathogens of rice and groundnut
viz., R. solani, Helminthosporium oryzae, Pyricularia oryzae, Sarocladium oryzae and
Sclerotium rolfsii even at 0.5 ppm. There was no hexaconazole residues detected in
different parts of rice and groundnut after harvest.
CONTENTS
Chapter No. Title Page No.
1
1 INTRODUCTION
6
2 REVIEW OF LITERATURE
37
3 MATERIALS AND METHODS
58
4 EXPERIMENTAL RESULTS
134
5 DISCUSSION
151
6 SUMMARY
155
J
REFERENCES
174
APPENDIX