Control of brown root rot disease in tea (Camellia sinensis (L.) O Kuntze) by using some systemic fungicides

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1 Academia Journal of Scientific Research 4(1): , January 2016 DOI: /ajsr ISSN: Academia Publishing Research Paper Control of brown root rot disease in tea (Camellia sinensis (L.) O Kuntze) by using some systemic fungicides Accepted 18 th January, 2016 ABSTRACT Pranjal Morang 1 *, Biman Kumar Dutta 2, Dileep Kumar B.S. 3 and Dhurva Kumar Jha 1 1 Department of Botany, Gauhati University, Guwhati, Assam, India, Department of Ecology, Assam University, Silchar, Assam, India, Agroforestry and Natural Products Division, NIIST (CSIR), Thiruvananthapuram, Kerala, India. *Corresponding author. pmorangaus.009@gmail.com. Five systemic fungicides (hexaconazole, propiconazole, bavistin, rook and ektino) were screened against the tea root pathogen brown root rot Fomes lamoensis in vitro. From the study, it was found that hexaconazole, propiconazole and bavistin were effective in inhibiting the radial growth of the pathogen at all three concentrations of the chemicals that is, 10, 50 and 100 ppm. at 100 ppm showed maximum 100% inhibition where roko and ektino have no inhibition against the pathogen. In nursery experiment, the effective chemicals (hexaconazole, propiconazole and bavistin) were evaluated at different concentrations. Under these conditions, hexaconazole was most effective and exhibited control of brown root rot disease followed by propiconazole and bavistin. The highest numbers of new leaves, lateral branches, shoot height, root length, fresh and dry weight of shoot and root were observed in tea plant treated with the chemical propiconazole and pathogen infested soil followed by hexaconazole and least was recorded in bavistin. Key words: Brown root rot, growth and biomass, systemic fungicides, tea. INTRODUCTION Tea is considered as one of the most important nonalcoholic cheapest beverages in the world. Tea is grown in more than 50 countries lying between 43 N and 42 S latitudes and situated at 2300 m above mean sea level. Brown root rot disease is caused by Fomes lamoensis (Murr.) Sacc. and Trott. This disease is prevalent in all tea growing areas of Barak valley of Assam, India (Morang, 2013). Infection occurs by infected material coming into contact with healthy plants (Satyanarana and Venkataramanan, 1979). Root diseases are insidious and loss caused by staggering. There are legacies of jungles that spread to tea fields which are planted after clearing the jungle. The diseases are transmitted to young tea plants whenever their roots come in contact with the left over roots of jungle trees harbouring the pathogenic organisms. Once the infection is established, the diseases spread to the neighbouring plants by root contact and aerial dispersal of spores (Chandra, 1999). Due to non availability of suitable fungicides to control primary root disease of tea, some advances have been made and some excellent control of brown root rot disease are achieved by the chemical method, mostly soil fumigation (Vapam, shell D-D, Chlorobromo propane formalin and Nemagon) (Shanmuganathan, 1964). Methyl bromide was reported to be useful in controlling certain primary root diseases (Shanmuganathan and Redlich, 1965; Venkata Ram, 1972b). Certain phytosanitory measures are useful in addition to fumigation of the affected area. Soil fumigation by a chemical, Durofume which is a mixture Methyl bromide and Ethylene dibromide is recommended to control the primary root diseases. Before taking up the fumigation, all dead and dying branches are to be cleared in addition to the dead bushes. Morang (2012) reported that the use of systemic fungicides was found to be effective in controlling brown

2 Academia Journal of Scientific Research; Morang et al. 009 Table 1. Name of the systemic fungicides for the present study S/ No. Common name Chemical name Trade name 1 2-(2,4 dichlorophenyl)-1-(1h 1,2,4-triazole-1-yl)hexan-2-ol Xantho 5% E.C 2 1-[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-ylmethyl]-1-H-1 TILT 25% E.C 3 Carbendazim N-(benzinmidazoly-2) methyl carbamate 50% W/P 4 Thiophenate methyl Dimethy [(1,2-phenylene)bis-(iminocarbonothioyl)] bis [carbamate] (56 Roko 70% W/P 5 Tricychazole 1,2,4-Triazole[-3,4-b]benzothiazole,5-methyl-( ) Ektino 75%W/P root rot in tea in vitro. Excessive use of chemicals has posed serious problems of environmental contamination through interference in the food chain. Thus, there is a continuous need for safer and ecologically tenable pesticides/fungicides. Protectant fungicides are used as prophylactic chemicals, as they act outside the plant prior to infection by the pathogen. It is the treatment intended to prevent or protect the plant against infection. Protectant fungicides which may be applied to seeds, soil or plant surface cannot penetrate into plant tissue in effective amounts. In contrast, systemic fungicides, which are taken up by the plants cure established infection (Dutta, 1980; Crowdy and Pramer, 1955). Keeping the aforementioned in view the present work was carried out to select suitable fungicides at minimum concentration for controlling brown root rot disease of tea. MATERIALS AND METHODS Five systemic fungicides were selected for the experiment (Table 1). In vitro efficacy study of the fungicides Fungicides were tested at three different concentrations of 10, 50 and 100 ppm (100 mg/l) for their efficacy against F. lamoensis using the poison food technique (Dhingra and Sinclair, 1985). Different concentrations of fungicides were prepared by dissolving the requisite quantity of each fungicide in warm PDA before autoclaving. The autoclaved media were poured into petri dishes and allowed to cool. An actively growing 7 days old culture of F. lamoensis was cut into 5 mm diameter discs using cork borer and placed at the centre of the petri dish containing the media plus different concentrations of fungicides in each treatment. Each treatment was maintained in triplicate. Media without fungicide served as control. The plates were incubated at 25 C ± 2 for 7 days. On the 8 th day radial growth of the mycelial colony was recorded and the percentage inhibition of growth calculated using the following formula: I = 100 (C T)/C Where: I= percent inhibition C= Control T= Growth of fungus in treatment. Growth promotion and disease control studies under nursery condition using fungicides Brown root rot pathogen Fomes lamoensis was grown in Potato Dextrose Broth (PDB). This was prepared using a 7 -day-old actively growing mycelium of the culture, homogenized in sterile distilled water using mortar and pestle. One year old tea plants were planted in polythene bags and inoculated with the homogenized fungal suspension at 50 ml per plant. Simultaneously, fungicides hexaconazole, propiconazole and bavistin at the concentration of 100 mg/l (100 ppm) were prepared for application to the collar region at 25 ml each of the tea plants. Each treatment had five replication; each replicates implies 10 plants. Disease assessment was done taking the following parameters such as drying of leaves, leaf shedding and drying of tea plants. Growth promotion study was done with the parameters like number of new leaves, shoot height, root length, dry weight of shoots and dry weight of roots. From the in vitro study, rook and ektino found less percent of inhibition against the pathogen therefore, the nursery experiment was done using the following treatments: i) Fomes lamoensis alone, ii) + Fomes lamoensis, iii) + Fomes lamoensis, iv) + Fomes lamoensis, v), vi) and vii). Statistical analysis All the data obtained were subject to multiple comparisons between the groups subsequently performed by the Least Significant Difference (LSD) at a significant level of RESULTS AND DISCUSSION In vitro management study From the study, it was observed that hexaconazole,

3 Academia Journal of Scientific Research; Morang et al. 010 Table 2. Effect of fungicides at different concentration on the radial growth of Fomes lamoensis in vitro (7 th day after treatment). Treatment Concentration (mg/l) Fungal growth (cm) Growth inhibition (%) ± 0.03 a 0.74 ± 0.74 a ± 0.11 a 5.92 ± 1.48 b ± 0.14 b ± 3.22 c Roko ± 0.05 a 2.22 ± 1.28 d ± 0.05 a 4.44 ± 1.28 e ± 0.00 a 5.18 ± 0.74 f Ektino ± 0.10 a 2.22 ± 2.22 d ± 0.05 a 2.22 ± 1.28 d ± 0.06 a 1.48 ± 1.48 g ± 0.06 ac ±1.28 ah ± 0.05 d ± 1.20 h ± 0.00 e ± 0.00 i ± 0.11 af ± 2.56 j ± 0.05 g ± 1.09 k ± 0.06 h ± 1.48 h Control ± 0.00 a 0.00 ± 0.00 a Values are average from five sets each; values are mean ± SE. The values followed by the same letter(s) do not differ significantly (p<0.05). propiconazole and bavistin showed inhibitory effect at different concentrations (10, 50 and 100 ppm) on radial growth of F. lamoensis corresponding to the day of observation in vitro. The effect of fungicides on the percent inhibition on the radial growth of F. lamoensis is presented in Table 2. Among the systemic fungicides tested, hexaconazole showed 100% inhibition on radial growth of F. lamoensis in vitro, followed by propiconazole (98.51%), (12.58%), Roko (5.18%) and Ektino (1.48%). It was also observed that hexaconazole in all the concentrations (10, 50 and 100 ppm) showed high percent growth inhibition against the pathogen (86.66, and %) respectively in vitro. The antifungal activity of systemic fungicides was reported to be the result of their ability to inhibit ergosterol bio- synthesis in fungi (Anonymous, 1985; Dutta and Debnath, 1990; Dutta, 1994; Agnihothrudu, 1990). It was also reported that hexaconazole and propiconazole were found to be more effective even at low concentration against the pathogenic fungus (Sarkar et al., 2010). It was further reported that the antifungal acitivity of triflumizole was observed (which act as a selective inhibitor of dimethylation) during the egosterol biosynthesis (Mizuno, 1988). Increased percent inhibition of the radial growth of the fungus was observed in both hexaconazole and propiconazole with the increase in concentration; on the other hand, no increase of inhibition was observed in the case of bavistin, roko and ektino treatment with the increase in their concentration. Among the systemic fungicides, hexaconazole was found to be highly effective in inhibiting the growth of the pathogen at the lowest concentration of 10 ppm (86.66%), followed by propiconazole (37.77%). Similar results were also observed with the tea pathogens Hypoxylon serpens (Onsando, 1986), Colletotrichum gloeosporoides (Ali et al., 1993), Pestalotia theae (Dutta and Begum, 1989) and Phomopsis theae (Ponmurugan et al., 2006). A systemic fungicide such as bitertanol was reported to be effective in controlling grey blight of tea in Korea (Shin, 2000). Growth promotion and disease suppression study under nursery condition using fungicides Initial symptoms of the disease occurred 30 days onward and became prominent up to 90 days. The leaves started drying followed by shedding and finally, whole plants and roots died. Here, in the pathogen (F. lamoensis) alone treated plants drying of leaf followed by shredding occurred from the 28 th day to 30 th day and finally, drying of the entire plants occurred on 90 th days onwards. Whereas, in pathogen treated with hexaconazole, propiconazole and bavistin initially leaf drying occurred on the 49 th, 47 th and 39 th day respectively but did not show any drying symptoms of the plants till the 90 th day of observation (Table 3). Evaluation of the number of triazole fungicides in recent years revealed that the formulation containing cyproconazole, hexaconazole, propiconazole and tebuconazole have been excellent in controlling blister blight of tea (Premkumar et al., 1998; Nithyameenakshi et al., 2010). The efficacy was improved when triazole was used in combination with copper oxychloride (Chandra

4 Academia Journal of Scientific Research; Morang et al. 011 Table 3. Effect of fungicidal treatment on the disease symptoms development in the F. lamoensis infected tea plants. Treatment (at 100 ppm) 1 leaf Leaf drying 2 leaves More than 2 leaves Leaf shedding 1 leaf 2 leaves More than 2 leaves Drying of tea plants Control (F. lamoensis alone) 28 th day 31 st day 36 th day 30 th day 39 th day 48 th day 90 th day + F. lamoensis 49 th day 56 th day - 54 th day 65 th day F. lamoensis 47 th day 58 th day - 52 nd day F. lamoensis 39 th day 47 th day 64 th day 44 th day 57 th day 66 th day Table 4. Development of new leaves and lateral branches in the F. lamoensis infected tea plants treated with fungicides (120 DAT). Treatment Concentration (ppm) Number of lateral branches Number of new leaves Control (F. lamoensis alone ) (203.03) 2.66 (60.24) + F. lamoensis (303) 2.00 (20.48) (404.54) 3.00 (80.73) + F. lamoensis + F. lamoensis (151.51) 1.66 (0.00) (303) 2.66 (60.24) (303) 3.00 (80.72) (101.52) 1.66 (0.00) (203.02) 1.66 (0.00) (203.02) 2.00 (20.48) (253.03) 2.33 (40.36) (303) 3.00 (80.72) (354.45) 5.00 (201.2) (101.51) 2 (20.48) (253.03) 3.33 (10.06) (354) 4.00 (140.96) (0.00) 1.60 (0.0) (51.54) 3.00 (80.72) (203.02) 2.60 (60.24) LSD at 5% level Values are Mean ± SE, Data within parentheses denotes percent increase over control. and Agnihuthrudu, 1989). Strobilurin fungicides were reported to be effective at very low concentration (12 to 20 ppm) (Wong and Wilcox, 2002; Miller and Gubler, 2004). Effects of different fungicides on control of brown root rot disease and growth promotion All the chemical treatments had significant effects in the percent increase of shoot height, root length, number of leaves and lateral branches over the control under nursery condition. When fungicides were applied as soil drenched to the rhizosphere of tea plants in polythene bags, significant growth promotion was observed. It was observed that in one year old tea plants number of lateral branches were highest in treatment hexaconazole + F. lamoensis in 100 ppm concentration (404.54%) followed by propiconazole + F. lamoensis (303%) and bavistin+ F. Lamoensis (203.02%). It was also observed that in fungicides alone treated in tea plants hexaconazole (354.45%) showed increase in the number of lateral branches as compared to propiconazole (354%) and bavistin (203.02%) (Table 4).

5 Academia Journal of Scientific Research; Morang et al. 012 Table 5. Effect of some fungicides on the shoot and root length of the F. lamoensis infected tea plants (120 DAT). Treatment Concentration (ppm) Shoot height (cm) Root length (cm) Control (F. lamoensis alone ) ± ± ± 1.05 (23.51) ± 1.46 (17.99) + F. lamoensis ± 2.66 (36.45) ± 1.71 (52.98) ± 1.12 (55.13) ± 2.46 (48.47) + F. lamoensis ± 2.11 (22.99) ± 1.62 (42.02) ± 1.10 (63.76) ± 2.51 (53.57) ± 2.29 (64.10) ± 1.38 (59.78) + F. lamoensis ± 0.12 (0.04) ± 0.32 (0.02) ± 0.3 (0.03) ± 0.17 (0.05) ± 0.14 (0.06) ± 0.34 (0.02) ± 0.89 (28.99) ± 1.29 (27.96) ± 1.24 (40.94) ± 1.41 (32.64) ± 1.90 (23.38) ± 1.80 (38.92) ± 2.06 (35.72) ± 1.47 (35.75) ± 3.13 (36.45) ± 0.52 (38.68) ± 1.00 (54.57) ± 1.18 (36.16) ± 0.77 (-0.01) ± 0.70 (0.03) ± 0.64 (0.02) ± 1.30 (-0.03) ± 0.73 (0.06) ± 0.86 (0.05) LSD at 5% level Values are Mean ± SE Data within parentheses denotes percent increase over control. It was observed that among the number of new leaves in the treated tea plants, hexaconazole was found to have the highest effect (201.20%) on to the increase in new leaves on tea plants as compared to propiconazole (140.96%) and bavistin (60.24%) (Table 4). On the other hand, highest percent increase over control in shoot height (64.10%) and root length (59.78%) were recorded in propiconazole + F. lamoensis followed by hexaconazole + F. lamoensis (55.13 and 48.47%) respectively, propiconazole (54.57%, 36.16) and hexaconazole (23.38 and 38.92%). Least percent increase in both shoot and root height were observed in treatment bavistin + F. lamoensis (0.06, 0.02%) and bavistin (0.06, 0.05%). Pathogen infested tea plants showed decrease in shoot height and root length (Table 5). Effect of different fungicide on the biomass of shoot Percent increase over control in fresh and dry weight of shoot was found in treatment with hexaconazole (100 ppm) (29.89 and 52.38%) followed by propiconazole (0.08 and 52.39%). Lowest fresh and dry weight of shoot was recorded in pathogen treated tea plants (Table 3). In treatment where fungicides as well as, pathogen were applied, highest percent increase over control was recorded in hexaconazole + F. lamoensis followed by propiconazole + F. lamoensis and bavistin + F. lamoensis. Highest increment in fresh and dry weight of shoot over respective pathogen treated tea plants (control) (36.95 and 69.04%) was observed in hexaconazole + F. lamoensis whereas; the lowest was recorded in bavistin + F. lamoensis (10.86 and 35.71%) (Table 6). Effect of different fungicide on the biomass of root It was observed that percent increase over control in fresh weight of root was recorded highest in hexaconazole (238.26%) followed by propiconazole (226.95%). It was also found that the highest percent increase over control in dry weight was noted in hexaconazole (174.46%) followed by propiconazole (161.70%). Lowest percent increase over control in both fresh and dry weight of root was recorded in bavistin ( and %). Highest increase in fresh

6 Academia Journal of Scientific Research; Morang et al. 013 Table 6. Effect of some fungicides on the fresh and dry weight of shoot of the F. lamoensis infected tea plants (120 DAT). Treatment Concentration (ppm) Fresh weight shoot (g) Dry weight shoot (g) Control (F. lamoensis alone ) ± ± ± 0.04 (0.09) 0.68 ± 0.03 (61.90) + F. lamoensis ± 0.04 (25.54) 0.76 ± 0.04 (80.95) ± 0.03 (36.95) 0.71 ± 0.08 (69.04) + F. lamoensis + F. lamoensis ± 0.12 (11.95) 0.62 ± 0.02 (47.61) ± 0.14 (20.64) 0.75 ± 0.03 (78.57) ± 0.06 (31.52) 0.81 ± 0.02 (92.85) ± 0.06 (-0.13) 0.45 ± 0.03 (0.07) ± 0.07 (11.95) 0.54 ± 0.02 (28.57) ± 0.04 (10.86) 0.57 ± 0.04 (35.71) ± 0.29 (0.05) 0.50 ± 0.12 (19.04) ± 0.32 (0.07) 0.60 ± 0.08 (42.85) ± 0.20 (29.89) 0.64 ± 0.04 (52.38) ± 0.13 (-0.00) 0.49 ± 0.05 (16.67) ± 0.25 (0.07) 0.56 ± 0.07 (33.33) ± 0.05 (0.08) 0.64 ± 0.03 (52.39) ± 0.03 (-0.15) 0.32 ± 0.02 (-0.23) ± 0.03 (-0.02) 0.52 ± 0.01 (23.80) ± 0.06 (0.00) 0.56 ± 0.03 (33.34) LSD at 5% level Values are Mean ± SE, Data within parentheses denotes percent increase over control. Table 7. Effect of some fungicides on the fresh weight and dry weight of root of the F. lamoensis infected tea plants (120 DAT). Treatment Concentration (ppm) Fresh weight of root (g) Dry weight of root (g) Control (F. lamoensis alone ) ± ± F. lamoensis ± 0.06 (226.95) 1.39 ± 0.05 (195.74) ± 0.15 (256.52) 1.58 ± 0.08 (236.17) ± 0.28 (259.13) 1.72 ± 0.12 (265.95) + F. lamoensis ± 0.20 (184.32) 1.15 ± 0.09 (144.68) ± 0.21 (207.82) 1.38 ± 0.13 (193.61) ± 0.17 (274.78) 1.62 ± 0.12 (244.68) + F. lamoensis ± 0.30 (149.56) 1.10 ± 0.05 (134.04) ± 0.52 (140.00) 1.01 ± 0.20 (114.89) ± 0.18 (173.98) 1.22 ± 0.05 (157.57) ± 0.27 (216.52) 1.27 ± 0.02 (170.21) ± 0.24 (213.00) 1.27 ± 0.05 (170.22) ± 0.10 (238.26) 1.29 ± 0.04 (174.46) ± 0.12 (166.08) 1.20 ± 0.10 (155.31) ± 0.10 (185.21) 1.25 ± 0.08 (165.95) ± 0.33 (226.95) 1.23 ± 0.13 (161.70)

7 Academia Journal of Scientific Research; Morang et al. 014 Table 7 contd. Effect of some fungicides on the fresh weight and dry weight of root of the F. lamoensis infected tea plants (120 DAT) Treatment Concentration (ppm) Fresh weight of root (g) Dry weight of root (g) ± 0.10 (151.30) 0.93 ± 0.04 (97.89) ± 0.21 (184.34) 1.20 ± 0.11 (155.31) ± 0.64 (185.21) 1.41 ± 0.17 (142.57) LSD at 5% level Values are Mean ± SE, Data within parentheses denotes percent increase over control. (274.78%) and dry weight (244.68%) of tea plants treated with the fungicides as well as, the pathogen, was recorded in treatments with propiconazole + F. lamoensis followed by hexaconazole + F. lamoensis ( and %) and bavistin + F. lamoensis ( and %). In all the aforementioned treatments fungicides were found having the effect in both fresh and dry weight of root (Table 7). In fungicides treated plants, shoot height and root length measurement in the Hexaconaxole,, and treatment increased with increase in the concentration of the fungicides used (10, 50 and 100 ppm). The fresh and dry weights of shoot and root were also found to be highest in fungicide treated tea plants as compared to the control (F. lamoensis inoculated). The results obtained in the present work are similar to those of Dimond (1967), who reported that the chemotherapeutic compounds helps to get rid of the host of an established infection. Use of fungicides increases the plant height as well as, the yield of tomato and Zea mays L. (Dutta, 1980; Siddiqui and Zaman, 2004). According to Dutta (1994), the production of higher yield in fungicides treated plants is due to the change in metabolism of the fungicides treated plants. Conclusion In the present study, fungicides hexaconazole and propiconazole at low concentrations (100 ppm) controlled the brown root rot disease of tea both in vitro and in nursery conditions. Besides controlling of root disease, it was also found that the tea plants treated with chemicals showed positive response in growth of the tea plants. It is concluded that there is the need for large field experiment for the benefit of the tea industry. ACKNOWLEDGEMENT The author Pranjal Morang is grateful to the University Grant Commission, New Delhi for Financial support. REFERENCES Agnihothrudu V, Chandra M (1990). Blister blight of tea and its control. The planters chronicle, Pp Ali MA, Ali M, Huq M, Ahmed M (1993). In vitro studies on fungicides against Colletorichum gloeosporoides (Penz). Sac. The die back of tea. S.L.J. Tea Sci. 62: Anonymous (1985). ANVIL Fungicide Technical Bulletin. Imperical Chemical Industries PLC, Plant Protection Division, Fernhurst, Haslemere, Survey, England, Pp Chandra Mouli B (1999). Global status of Tea Disease Management Strategies in N.K. Jain (eds). Global Advances in Tea Sciences, Aravelli Books Int. Ltd., New Delhi. Pp Chandramouli B, Agnihothrudo V (1989). Disease management in tea, blister blight control. UPASI Tea Sci. Dept. Bull. 43: Crowdy BH, Pramer (1955). Movement of antibiotic in higher plants. Chem. Inc. 7: Dhingra OD, Sinclair JB (1985). Basic plant pathology methods: CRC Press, Inc.: Boca Raton, FL. Dimond AE (1967). In Plant Pathology: Problems and Progress The golden Jubilee volume of the American Phyotopathological Society. Pp Dutta BK, Debnath S (1990). Disease forecasting as an aid to control blister blight disease of tea caused by Exobasidium vexans in Darjeeling District. International conference on Tea R and D, Pp Dutta BK (1980). Studies on wilt disease caused by Verticillium alboatrum R. and B. in relation to some systemic fungicides. J. Indian Bot. Soc. 59: Dutta BK (1994). Potential of systemic fungicides in the management of tea diseases. 32nd Tocklai conference, TRA, Jorhat, Assam, Pp Dutta P, Begum R (1989). In vitro studies on the efficacy of fungicides against Pestalotia theae the gray blight of tea. Two and a Bud. 34: Miller TC, Gubler WD (2004). Sensitivity of Caliform isolates of Uncinula necator to Trifloxystrobin and Spiroxamine, and update on Triadimefon sensitivity. Am. Phytopathol. Soc. 88: Mizuno M (1988). Triflumizole (Trifmine ). A new broad spectrum fungicides. Jap. pest. inf. 52: Morang P, Dutta BK, Dileep Kumar BS (2012). Efficacy of systemic fungicides against brown root rot (Fomes lamoensis) disease of tea (Camellia sinensis) in vitro and in nursery condition. World J. Agric. Sci. 8(3): Morang P (2013). Integrated management of brown root rot disease of tea (Camellia sinensis (L.) O Kuntze.) under the agroclimatic condition of Barak Valley of Assam. Ph.D. Thesis, Assam University, Silchar. Nithyameenakshi S, Jeyaramraja PR, Manian S (2010). Evaluation of azoxystrobin and difenoconazole against certain crop diseases. Int. J. Agric. Res. 5(10): Ponmurugan P, Baby UI, Gopi C (2006). Efficacy of certain fungicides against Phomopsis theae under in vitro conditions. Afri. J. Biotech. 5(5): Premkumar R, Baby UI, Chandramouli B (1998). Systemic activity and field performance of Triazole fungicides against blister blight pathogen of tea. In: Mathew, N.M., Kuruvilla Jacob (eds.), Development in

8 Academia Journal of Scientific Research; Morang et al. 015 plantation crops research. Alled Publishers Limited, New Delhi. pp Sarkar S, Narayanan P, Divakaran A, Balamurugan A, Premkumar R (2010). The in vitro effect of certain fungicides, insecticides and biopesticides on mycelial growth in the biocontrol fungus Trichoderma harzianum. Turk. J. Biol. 34: Satyanarana G, Venkataramanan M N (1979): Mycorrhiza from tea and associated with in Assam. In: Placrosym Ootacamund. Pp Shanmuganathan N (1964). Recent developments in control of Poria root disease. Tea Quart. 35: Shanmuganathan N, Redlich WW (1965). Control of poria root disease with methyl bromide. Tea Quart. 36: Siddiqui ZS, Zaman AU (2004). Effect of benlate systemic fungicide on seed germination, seedling growth, biomass and phenolic contents in two cultivars of Zea mays L. Pak. J. Bot. 56(3): Shin GH, Hur JS, Koh YJ (2000). Chemical control of gray blight of tea in Korea. Plant Pathol. J. 16(3): Venkata Ram CS, Chandramouli B (1976). Systemic fungicides for integrated blister blight control. UPASI Tea sci. Dep. Bull. 33: Venkta Ram CS (1972b). Control of red and brown root rot diseases in tea. Planters Chronicle 67: Wong EP, Wilcox WE (2002). Sensitivity of azoxystrobin among isolates of Uncinula necator, Baseline distribution and relationship to myclobutanil sensitivity. Plant Dis. 86: Cite this article as: Morang P, Dutta BK, Kumar BSD, Jha DK (2016). Control of brown root rot disease in tea (Camellia sinensis (L.) O Kuntze) by using some systemic fungicides. Acad. J. Sci. Res. 4(1): Submit your manuscript at