Jeyaraman and Robert BMC Plant Biology (2018) 18:222
https://doi.org/10.1186/s12870-018-1445-8
RESEARCH ARTICLE
Open Access
Bio efficacy of indigenous biological agents
and selected fungicides against branch
canker disease of (Macrophoma theicola)
tea under field level
Mareeswaran Jeyaraman* and Premkumar Samuel Asir Robert
Abstract
Background: Branch canker caused by Macrophoma theicola is a major stem disease of tea plants (Camellia spp.).
In tea plantations, this disease causes crop loss and it is one of the major limiting factor for yield stagnation. In very
few instances it causes considerable damage in new clearings (about 3 or 4 years old) and large number of bushes
have been killed. As there is no control measures for branch canker disease in south Indian tea plantation, this field
study was conducted in naturally infected pruned tea field at UPASI Tea Research Institute (Good Agricultural
Practice), Valparai, Tamil Nadu, India.
Methods: The chemical fungicides, biological agents and bio products were evaluated under naturally infected
field of seedling plants for two consecutive disease seasons (2014–2015) and there was 11 treatments with three
applications. All the treatments were carried out in the time of February–March and October–November (2014–
2015). The two set of application was conducted per year. Each set contains eight rounds during the month of
February–March as well as October–November (2014–2015). The chemical fungicides, biological agents and
commercial bio products were measured as per UPASI- TRF, recommendation viz., COC (50 g/ha and 0.2 g/plot),
Companion (20 g/ha and 0.08 g/plot), biological agent of Bacillus amyloliquefaciens, Tichoderma harzianum,
Gliocladium virens and Beauveria bassiana (5 kg/ha and 20.8 g/plot) and bio product of Tari (1 L/ha and 4.2 ml/plot)
and Tricure (1 L/ha and 4.2 ml/plot).
Results: The present investigation revealed the integrated application of Companion/Bacillus amyloliquefaciens
showed superior control of branch canker disease followed by the treatment with Companion alone under field
condition. Copper oxychloride/Bacillus amyloliquefaciens was moderately effective followed by Copper oxychloride.
The significantly reduced canker size was recorded with treatment of Bacillus amyloliquefaciens followed by
commercial organic fungicides of Tari (Organic Tea Special) and Tricure (0.03% Azadirachtin). The least canker size
was observed with Gliocladium virens followed by Beauveria bassiana. Branch canker disease incidence was
increased in untreated control plants when compared to treated plants.
(Continued on next page)
* Correspondence: mareeswaran92@yahoo.com
Plant Pathology Department, UPASI Tea Research Institute, Coimbatore
District, Valparai, Tamil Nadu 642127, India
© The Author(s). 2018 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
Jeyaraman and Robert BMC Plant Biology (2018) 18:222
Page 2 of 6
(Continued from previous page)
Conclusion: Among these 11 treatments, the integrated treatment of companion at rate of 0.08 g and Bacillus
amyloliquefaciens (20.8 g) showed the most significantly decreased canker size (DPL, 5.76) followed by another
treatment with companion (0.08 g) (DPL, 4.11). The moderate reduction of canker size was observed by the
treatment with Copper oxychloride (0.2 g)/Bacillus amyloliquefaciens (20.8 g) (DPL, 3.05) followed by the treatment
of copper oxychloride alone (DPL, 1.74). Therefore, the integrated application of Companion/Bacillus
amyloliquefaciens proved significantly effective in the management of branch canker disease under the field
conditions.
Keywords: Biocontrol, Canker size, Chemicals, Field evaluation
Background
Tea is the most standard and widely accepted nonalcoholic beverage consumed mainly for its refreshing,
mild stimulant effect, medicinal and cosmetic purpose.
In commonly cultivated crop shoot contains three leaves
and a bud which is used to manufacture different types
of tea viz., green tea (non-fermented), black tea (fermented) and oolong tea (semi-fermented) consumed by various group of people according to their tastes. India
produces about 1191.1 million kgs of tea from 5,
79,353 ha and in south India around 1, 19,740 ha is
grown in Western ghats. In 2015–16 it is estimated that
Out of the world’s total production of 5200.3 million kg
of tea, 42.9% was produced from China followed by
India (22.9%), Kenya (7.7%), Sri Lanka (6.3%), Vietnam
(3.2%), Turkey (4.4%), Indonesia (2.5%), Argentina
(1.6%), Japan (1.6%), Bangladesh (1.3%), Uganda (1.0%),
Malawi (0.7%), Tanzania (0.6%) and Zimbabwe (0.2%).
Although tea production in India was more than 1000
million kg, due to high demand of domestic consumption, it is only 13.0% was exported.[1] The first three tea
exporting countries are Kenya (25.2%), Sri Lanka (17.2%)
and China (18.5%).[1] Crop loss due to canker diseases
depends upon severity of pathogen affected infection
and the geographical area [2]. Branch canker disease is
one of the most serious stem pathogen affected during
dry conditions and cause the death of tea bushes more
than 40% [3]. All parts of the tea bush viz., foliage, stem
and roots are susceptible to diseases and crop loss due
to pests and various diseases is around 10–15% [4]. Tea
is grown in a wide range of soil types that are acidic in
nature and tea soils are latosols in south India [5]. Tea is
a monoculture crop and their diseases are classified as
leaf, stem and root diseases. The stem diseases are categorized namely collar canker, branch canker, wood rot
and thorny stem blight. The branch canker disease is
caused by Macrophoma theicola which is the major stem
disease in south Indian tea plantation. Depends upon
the disease severity it causes crop loss and yield stagnations. Previous studies from Taiwan and south-east
Asia states that branch canker disease pathogen
caused by Macrophoma theicola as twig die-back of
tea plants and around 40% of tea plants were killed
by this disease [4, 6, 7].
The stem diseases such as collar canker (Phomopsis
theae) and branch canker (Macrophoma theicola) creates
low yield which are reported from Central Africa [8]. In
nursery level conditions, the different tea cultivars are infected by branch canker pathogen Macrophoma theicola
[9]. Under in vitro conditions, the data available for branch
canker disease is very less. Therefore, the initial findings analyzed the branch canker disease characteristic feature, influence of biotic factors viz., pH, temperature and light on
pathogen and mycotoxin compounds for disease development in tea plants [10].
The changes in the biochemicals characteristics such
as total carbohydrate, reducing sugar and nutrient status
of N, P and K were affected by branch canker disease in
different tea cultivars under glass house conditions [11].
The entomopathogens Beauveria bassiana and Paecilomyces sp. used as biocontrol agents as well as biological
control of Bacillus spp. and Trichoderma sp. showed
good results against the branch canker disease [12, 13].
The different plant aqueous extracts, chemical fungicide
of companion, commercial bio product of Tari and Tricure have been reported as control measures for branch
canker pathogen under in vitro conditions [14, 15]. In
current situation, there is lack of protection mechanism
available for branch canker disease under field level for
consecutive disease seasons and it’s very difficult to control this canker during pruning season. The novelty relies in the integrated application of reduced usage of
chemical in tea soil as well as by improving the soil
health and minimizing the canker incidence level in tea
plantation. As far as, in south Indian tea plantation there
is no recommendation for branch canker disease. Therefore, the present investigation has been attempted to
control branch canker disease with an integrated application of various fungicides and biological control under
field level by limiting the usage of chemicals.
Results
The canker size was reduced significantly after explore of
treatments under field condition. Generally, an integrated
Jeyaraman and Robert BMC Plant Biology (2018) 18:222
Page 3 of 6
applications method showed more effectively than straight
applications of fungicides. Among the various treatments,
the present study revealed that highest reduction of canker size was measured with an integrated treatment of
Companion/B.amyloliquefaciens followed by straight application of Companion (Table 1). The moderate reduction of canker size was recorded with an integrated
spraying of Copper oxychloride/B.amyloliquefaciens
followed by separate application of Copper oxychloride
(Table 1). Furthermore, bacterial strain of B.amyloliquefaciens was considerably reduced the canker size followed by
the treatment of organic fungicides Tari (Organic Tea Special) and Tricure (0.03% Azadiractin). The least canker size
was noted with fungal biocontrol agent of Gliocladium
virens, Beauveria bassiana and Trichoderma harzianum.
The untreated control plants clearly indicated that canker
size was increased than the treated plants (Table 1).
Discussion
Generally, there are several integrated disease management reports are available with the combinations of fungicides and biological agents which reduce the disease
severity as well as improve the plant health. Earlier findings also reported that combination of bacterial bio
agent Pseudomonas fluorescens with reduced dose of
fungicide to control the pencillium rot in pear and combinations of fungicides with yeast have been reported as
better integrated application for control the pathogen
Botrytis cinerea in geranium seedlings [16, 17].
The present study showed that integrated application
of Companion/B.amyloliquefaciens (DPL, 5.76) was
found to provide good results against branch canker disease followed by unaccompanied treatment of Companion (DPL, 4.11) (Table 1). This result was in agreement
with the integrated treatment of Trichoderma harzianum, Rhizobium and carbendazim proved significantly
effective in the management of Sclerotium root rot of
groundnut [18]. Previous report supported that combination fungicide of Companion (Mancozeb 63% + Carbendazim 12%) showed better results against the root rot
disease of chilli which is caused by Sclerotium rolfsii as
well as the superior effect of Companion are proved
against botrytis gray mold disease caused by Botrytis
cinerea in paprika plant [19, 20].
The present result revealed that Copper oxychloride/
B.amyloliquefaciens (DPL, 3.05) was noticed adequately
in reduction of canker size followed by separate treatment of Copper oxychloride (DPL, 1.74) (Table 1). Previous study supported that the moderate reduction of
canker size by the combine application of Copper
oxychloride + Bacillus sp. (Disease protection score,
3.03 cm) [21]. The treatment with contact fungicide
Copper oxychloride suggested against the late blight
(Phytophthora infestans) and early blight diseases (Alternaria solani) in potato plant [22].
The present investigation showed that significant reduction of canker size by the treatment with Bacillus
amyloliquefaciens (DPL, 1.60) followed by the treatment
of Tari (Organic Tea Special) and Tricure (0.03% Azadiractin) (Table 1). Our study was in concordance with the
previous report that bacterial strain Bacillus amyloliquefaciens inhibited the growth and Sclerotia production of
Table 1 Evaluation of biological control and fungicides against branch canker disease in tea
S.No Treatment details
Canker Size (cm)
Disease Protection Level (DPL)
Pre-Assessment
Post-Assessment
Wound Healing (WH)
Length in cm (L1) Width in cm (W1) Length in cm (L2) Width in cm (W2) WH = (L1 - L2) + (W1- W2) in cm
1
Copper oxychloride
7.97
2.53
6.73
2.03
1.74
2
Companion
13.60
4.73
11.19
3.03
4.11
3
Bacillus amyloliquefaciens
6.63
3.50
5.56
2.97
1.60
4
Companion/B.amyloliquefaciens 14.43
4.10
10.95
1.82
5.76
5
COC/ B.amyloliquefaciens
12.97
3.37
10.88
2.41
3.05
6
Trichoderma harzianum
13.10
3.00
12.61
2.67
0.82
7
Gliocladium virens
9.43
2.70
8.43
2.41
1.29
8
Beauveria bassiana
7.50
2.70
6.97
2.29
0.94
9
Tari (Organic Tea Special)
6.23
2.33
5.19
1.96
1.41
10
Tricure (0.03%)
7.87
2.90
7.08
2.33
1.36
11
Control
14.50
3.63
17.49
5.74
−5.10
CV %
6.32
1.77
6.74
1.76
–
CD @ 5%
12.31
1.07
11.84
0.89
–
*Mean of three replications
Canker size (cm) was measured before treatment (pre-assessment length and width in cm) and after two years canker size was measured (post-assessment length
and width in cm) and their values are given
Jeyaraman and Robert BMC Plant Biology (2018) 18:222
Sclerotinia sclerotiorum at 3rd (4 ml culture filtrate
shows 55% inhibition) and 7th (4 ml culture filtrate
shows 55% inhibition) days of incubation [23].
The results of bio products obviously indicated that
Tari (Organic Tea Special) (DPL, 1.41) and Tricure
(0.03% Azadiractin) (DPL, 1.36) reduced the minimal
level of canker size (Table 1). The similar observations
were noticed with the use of Tari (Organic Tea Special)
(69.77 ± 2.83) and Tricure (0.03% Azadiractin) (100.0 ±
0.0) shows higher growth inhibition against branch canker pathogen Macrophoma theicola under in vitro conditions at 8% concentration [15].
Our study proved the fungal biocontrol Gliocladium
virens (DPL, 1.29) showed least level of canker size
(Table 1). The result was in negatively correlated with
the treatment of Gliocladium virens showed better control in reducing collar canker size in tea plants [24].
Whereas, In vitro antagonistic potential of Trichoderma
sp. and Gliocladium virens gave the best control against
root pathogens of tea plants [25]. Earlier report supported that integrated disease management to control
the basal stem rot of coconut by soil application of T.
viride [26].
Present study revealed that entomopathogen Beauveria bassiana (DPL, 0.94) was recorded least level of
canker size followed by Trichoderma harzianum (DPL,
0.82) (Table 1). Previous report recommended that Beauveria bassiana (64.22) showed higher antagonistic potential against branch canker pathogen Macrophoma spp. in
tea under in vitro [12]. Most of the reports suggested that
entomopathogens of Beauveria bassiana and Lecanicillium spp. have been identified as biocontrol for the plant
disease and soil plant pathogen such as Rhizoctonia sp.
Fusarium sp. and Pythium sp. [27–29]. Furthermore, the
previous report suggested that Trichoderma harzianum
and Trichoderma viride showed higher inhibitory effect
Page 4 of 6
against the pathogen Poria hypobrunnea causing stem
canker in tea plantation [30]. The observations were made
to control thorny stem blight using tea wood pellets colonized by T. harzianum and T. viride [31]. Finally, the
whole results are in source with integrated management
of branch canker disease in tea and the branch canker disease has been controlled by chemicals, biological control
and bio fungicides in tea plantation [32, 33].
Conclusion
From the above results, it might be concluded that branch
canker disease has been successfully recovered from infected field by using integrated application of chemicals and
biological control methods. The biological control of the
branch canker disease would considerably reduce the fungicide usage in the tea fields and harmful effects of the chemical residues. Our results proved that integrated application
of Companion/Bacillus amyloliquefaciens controls the
branch canker disease well under field conditions. The outcome of this study resulted in evolving an integrated approach to control the branch canker by minimal use of
chemical fungicides. As a final point, an integrated application of Companion/Bacillus amyloliquefaciens has been
identified as superior control of branch canker disease
under field condition. In future it could be studied by conducting multi-location field trails.
Methods
Field experiment of an integrated management of
branch canker disease was conducted at UPASI Tea Research Foundation, Tea Research Institute, Valparai located at 10° 23’ North and 77° 0′ East and about 1050 m
above MSL. Susceptible of seedling planted in 1961 area
at style of planting (1.2 × 1.2 m) and bush population
(6800 plants/ha) was conducted. An experiment was carried out in naturally infected pruned tea fields and there
Table 2 Treatment details and application dosage of chemicals and biological agents
Treatment details
Dose/ha
Dose/plot
Spraying interval
Copper oxychloride COC (50% WP)
50 g in 10 l of water
0.2 g/729 ml water volume
5 days
Companion
(Carbendazim 12% + Mancozeb 63% WP)
20 g/10 L
0.08 g/729 ml water volume
5 days
Bacillus amyloliquefaciens
5 kg/ha
20.8 g/729 ml water volume
5 days
Companion /
Bacillus amyloliquefaciens
20 g/10 L + 5 kg/ha
0.08 g/20.8 g/729 ml water volume
5 days
COC/Bacillus amyloliquefaciens
50 g in 10 L of water + 5 kg/ha
0.2 g/20.8 g/729 ml water volume
5 days
Trichoderma harzianum
5 kg/ha
20.8 g/729 ml water volume
5 days
Gliocladium virens
5 kg/ha
20.8 g/729 ml water volume
5 days
Beauveria bassiana
5 kg/ha
20.8 g/729 ml water volume
5 days
TARI (Organic Tea Special)
1000 ml/ha
4.2 ml/729 ml water volume
5 days
Tricure (0.03% Azadirachtin)
1000 ml/ha
4.2 ml/729 ml water volume
5 days
Control
–
Water
5 days
Jeyaraman and Robert BMC Plant Biology (2018) 18:222
was 11 treatments with three replications. Each replication consider as 25 bushes. All the treatments were laid
out in randomized block design. The incidence of
branch canker disease was assessed at before and after
treatment imposed. Treatments and their application details are given in Table 2. The two times of applications
per year during February–March and October–November (2014–2015) was studied to the trail plots. The
complete applications dosage was measured as per the
recommendation schedule of UPASI Tea Research Institute, Valparai, Tamil Nadu, India. The selected fungicides
of Copper oxychloride (Fytolan 50% WP) [Bayer Crop
Science Ltd.] at 0.2 g and Companion (Carbendazim
12% + Mancozeb 63% WP) [Bayer Crop Science Ltd.] at
0.08 g were explored at 729 ml water volume/25 bush
dosage. An indigenous biological control such as Trichoderma harzianum, Gliocladium virens, Beauveria bassiana and Bacillus amyloliquefaciens were obtained from
repository of Division Plant Pathology, UPASI Tea Research Institute, Valparai, Tamil Nadu, India. Biological
control agent was mixed with sterilized talc powder at
concentration level of 250 ml culture broth per kg of talc
and kept for 2 days of incubation at 25 ± 2 °C. Tricure
(0.03% Azadirachtin) at 4.2 ml, Tari (Organic Tea Special) at 4.2 ml and biological agents at 20.8 g were evaluated against the branch canker disease (Table 2).
Standard cultural practices spray was done by using a
Knapsack low volume sprayer at 5 days interval. The
commercial botanical fungicide Tricure (0.03% Azadirachtin) was procured from Margo Biocontrol Pvt., Ltd.,
Nashik, Maharashtra and Tari (Organic Tea Special) was
obtained from TARI BIO TECH, Tanjavur. Branch canker disease protection level was calculated by using following formula. Wound Healing (WH) = (L1-L2)
+ (W1-W2). Where L1- (Pre-assessment) canker size
length in cm, L2- (Post-assessment) canker size length in
cm, W1- (Pre-assessment) canker size in width (cm),
W2- (Post-assessment) canker size in width (cm).
Abbreviations
COC: Copper oxychloride.; DPL: Disease Protection Level.; GAP: Good
Agricultural Practice; L1: Pre-assessment of canker size in length (cm);
L2: Post-assessment of canker size in length (cm).; W1: Pre-assessment of
canker size in width (cm); W2: Post-assessment of canker size in width (cm).;
WH: Wound Healing
Acknowledgements
The authors are thankful to Dr. B. Radhakrishnan, Director, UPASI Tea
Research Institute, Valparai-642127, Tamil Nadu, India for the facilities and encouragement provided during the study.
Authors’ details
Dr. R. Premkumar Samuel Asir (Retd), Deputy Director, Head and Plant
Pathologist, Plant Pathology and Microbiology Division, UPASI Tea Research
Foundation, Tea Research Institute, Valparai-642,127, Coimbatore-Dt, Tamil
Nadu, India and J. Mareeswaran, Research Scholar, Plant Pathology and
Microbiology Division, UPASI Tea Research Foundation, Tea Research Institute, Valparai-642,127, Coimbatore-Dt, Tamil Nadu, India.
Page 5 of 6
Funding
At present we do not have any financial support from any funding agency
for this work. But, the BMC (waivers) Plant Biology Journal considered for
review process without processing charge.
Availability of data and materials
The raw data worked in the excel file are included in the supplementary
section.
Authors’ contributions
The experimental design and data was analyzed by PR. The manuscript has
been written by MJ. All authors read and approved the final manuscript.
Ethics approval and consent to participate
Cultivated tea plant was used in the study. The field study was complied
with institutional and national guidelines. No specific permits were needed.
Consent for publication
Not applicable.
Competing interests
The authors declare that they have no competing interests.
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations.
Received: 20 January 2018 Accepted: 27 September 2018
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