In Vitro Evaluation of Plant Extracts against seed borne bacteria and fungi of Hybrid Rice

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1 Applied Science Reports E-ISSN: / P-ISSN: DOI: /PSCP.ASR App. Sci. Report. 8 (2), 2014: PSCI Publications In Vitro Evaluation of Plant Extracts against seed borne bacteria and fungi of Hybrid Rice A.N. Faruq*, M. A. Rahman, F. M. Aminuzzaman, Md. Mamun-ur-Rashid and Sanzida Hoque Department of Plant Pathology, Sher-e-Bangla Agricultural University, Dhaka-1207, Bangladesh *Corresponding author nomanfarok@yahoo.com Paper Information Received: 8 September, 2014 Accepted: 8 November, 2014 Published: 20 November, 2014 Key words: Plant extracts, seed treatment, hybrid rice A B S T R A C T An investigation was carried out to evaluate the efficacy of some selected plant extract for seed treatment of hybrid rice in the seed health laboratory of department of Plant Pathology of Sher-e-Bangla Agricultural University during the period from January 2012 to June The experiment was carried out according to the rules of International Seed Testing Association (ISTA) and following Completely Randomized Design with four replications. Nine plants extracts viz. onion bulb, kalijira seed, allamonda leaf, garlic clove, neem leaf, datura leaf, turmeric rhizome, biskatali leaf and shimul leaf extract were evaluated against seed borne pathogens of hybrid rice. All of the botanical were used as per 1:1 (w/b) ratio. Two strains of a single bacterium and seven seed borne fungi were detected where Xanthomonas oryzae pv. oryzae (two strains), Rhizopus stolonifer, spp., Fusarium moniliforme were predominant. It was observed that, all of the varieties are highly susceptible to the bacterium Xanthomonas oryzae pv. oryzae. Hera 2, BRRI hybrid dhan2 and SL 8 are more susceptible to the strain 1 then strain 2. Among the plant extracts, datura leaf extract, turmeric rhizome extract; allamonda leaf extract and garlic clove extract showed best performance against the seed borne pathogens. Kalijira seed extract, bishkatali and shimul leaf extract also showed promising effect against seed borne fungi only. Datura leaf extract and turmeric rhizome extract have the highest bactericidal and anti fungal efficacy among the plant extracts used in this experiment. Considering the overall performance of plant extracts, datura leaf extract (1:1 w/b) and turmeric rhizome extract (1:1 w/b) could be used for seed treatment of hybrid rice as an eco friendly approach PSCI Publisher All rights reserved. Introduction Rice (Oryza sativa) is the staple food of Bangladesh and it constituted about 90% of the total food grain production (Huda, 2001). It covers about 75% of the total cultivable land in Bangladesh (BBS, 2008). The average world yield of rice is 3.84 tons/ha but the average yield of rice in Bangladesh is 2.52 ton/ha (BBS, 2007; FAO, 2002). In Bangladesh, hybrid rice has taken up significant land coverage due to active government attention, promotion of private seed companies and publication of mass media. Now the Government of Bangladesh heavily promoted hybrid seed cultivation to ensure the food security. Different seed companies have imported around 11,000 tones hybrid rice seed from China, India or Philippines in First it was considered as an alternative technology for breaking the present yield ceiling of modern varieties. However, the yield of these varieties is hampered by different factors. Major constrains in hybrid rice adoption were identified; these were high cost of seed, requirement of more crop care and management time, less yield gains, high pest and disease attack, low profits and lack of suitability for home consumption (AAS, 1999). The extremely seed borne pathogen of rice are Drechslera oryzae (Brown spot), Pyricularia oryzae (Blast), Fusarium moniliforme (Foot rot), Garlecia oryzae (Leaf scald) and Sarocladium oryzae (Narrow brown Leaf spot) (Ashrafuzzaman, 1991). Fakir (1988) reported 37 seed borne pathogens of rice in Bangladesh. Out of them 32 are fungi, 3 are bacteria, each of one are virus and nematode. Brown spot (Bipolaris oryzae), Bakanae (Fusarium moniliforme), Blast (Pyricularia oryzae), Sheath blight (Rizoctonia solani), Sheath rot (Sarocladium oryzae), Stem rot (Sclerotium oryzae), Bacterial leaf blight (Xanthomonas campestris pv. oryzae), Bacterial leaf strek (Xanthomonas campestris pv. oryzicola) and Tungro (Rice Tungro virus) are the most important seed borne diseases of rice in Bangladesh.

2 App. Sci. Report. 8 (2), 2014: The acceptable method for controlling of these diseases is sowing of pathogen free seeds. Treatment of seed with seed-dressing fungicides was found to improve germination and decrease infection of seed borne pathogens. Use of chemical to control a disease is the most favorable mean to our farmers. However, use of precise dose of the chemical for its application to the field is a difficult job for them. Indiscriminate and long time use of chemical affect the soil health and develop pathogen resistance. Use of alternate methods instead of seed treating chemicals is of great concern to save our environment. Therefore, it is judicious to explore less expensive, less risky non-chemical components to treat seeds for freedom from the seed-borne pathogens. Seed treatment with different plant extracts has been shown effective in controlling seed borne fungal pathogen. Islam (2006) reported that seed treatment with garlic clove extract and bishkatali extract was found effective in reducing the incidence of Bipolaris sorokiniana. Rahman (2007) also reported that seed treatment with garlic clove extract and turmeric rhizome extract resulted remarkable reduction of leaf blight severity of wheat. Ahmed (2000) reported that Biskatali, Garlic and Neem were effective against B. oryzae at 1:1 dilution. High quality seed is not only important for increased crop production, but also for proper establishment of sound seed industry in the country. Of the major characteristics of a quality seed, health is immensely important. Therefore, it is important to know whether a seed lot is free from seed-borne infection or not. This has great value to the growers. In fact, under favorable conditions such infected seeds can create disease epidemic in the field resulting partial to total crop failure. Now the land of our country is decreasing gradually but population is increasing. To fulfill the demand of increasing population, the cultivation of hybrid rice is increasing day by day. Almost all of hybrid rice varieties are imported from abroad. Rice seed play an important role to carry pathogen in quarantine aspect. Farmer s usually used different hybrid rice varieties and face the difficulties of many diseases. Last few years, Blast, BLB and BLS diseases appear seriously in the hybrid rice. Objection was made from some corner that those diseases extremely appear in the hybrid rice seeds. Considering the above facts, the present investigation was undertaken with the following objectives: To evaluate the seed health status of selected hybrid rice varieties; To evaluate the potentiality of plant extracts as seed treating agent against seed-borne pathogens of hybrid rice, and To screening selected botanicals against seed borne Xanthomonas bacterium of hybrid rice. Materials and Methods The experiment was carried out in the Seed Pathology Laboratory (SPL) and Plant Disease Diagnostic Laboratory (PDDL) of the Department of Plant Pathology of Sher-e-Bangla Agricultural University (SAU), Dhaka. Altogether nine seed samples of three hybrid rice variety viz. Hira-2, BRRI hybrid dhan2 and SL-8 were collected. Three seed samples were collected for each variety. BRRI hybrid dhan2 collected from Bangladesh Rice Research Institute, SL 8 collected from Bangladesh Agricultural Development Corporation (BADC) and Hira 2 variety collected from Supreme Seed Co. Ltd. Botanicals were collected from the local market. Nine seed treatments viz. T 2 = onion bulb extract, T 3 = kalijira seed extract, T 4 = allamonda leaf extract, T 5 = garlic clove extract, T 6 = neem leaf extract, T 7 = datura leaf extract, T 8 = turmeric rhizome extract, T 9 = biskatali leaf extract, T 10 = shimul leaf extract including untreated T 1 = control were assessed in the experiment. Table 1. The particulars of botanicals used in this study Common name English name Scientific name Plant parts used Dilution Neem Margosa tree Azadirachta indica Leaf 1:1 w/b Allamanda Allamanda Allamanda cathartica Leaf 1:1 w/b Garlic Garlic Allium sativum Clove 1:1 w/b Onion Onion Allium cepa Bulb 1:1 w/b Turmeric Turmeric Curcuma longa Rhizome 1:1 w/b Kalijira Cumin black Nigella sativa Seed 1:1 w/b Bishkatali Smart weed Polygonum hydropiper Leaf 1:1 w/b Datura Datura Datura metel Leaf 1:1 w/b Shimul Silk Cotton Tree Salmalia malabarica Leaf 1:1 w/b Seed health study by blotter method Seed samples treated with different seed treating agent will be subjected to seed health analysis for collecting data on suppressing seed borne pathogen. Blotter method will be done following the International Rules for Seed Health Testing (ISTA, 1996). In this method 9 cm diameter pyrex glass petridish and Whatman no.1 filter paper will be used. Two hundred seeds from each sample will be taken randomly and placed on the moist filter paper in eight replicate petridishes. The petridishes with treated seeds will then be incubated at C for seven days in the laboratory under the alternate cycle of 12 hours NUV light and under 12 hours fluorescent day light for 7 days. After incubation the seeds will be examined under stereomicroscope and the pathogens will be identified following the key of Mathur and Kongsdal (2003). Appropriate keys (Booth, 1971; Chidambaram and Mathur, 1975; Misra et al., 1994 and Malone and Muskette, 1964.) were consulted for identification of the fungi and bacteria. The results were presented as percent incidence for individual pathogen. 62

3 App. Sci. Report. 8 (2), 2014: Preparation of plant extract The extracts were prepared by using the method of Ashrafuzzaman and Hossain, For preparation of extracts, collected leaves were weighted in an electric balance and then washed in the water. After washing the big leaves were cut into small pieces. For getting extract, weighted plant parts were blended in an electric blender and then distilled water was added into the jug of the blender. The pulverized mass was squeezed through 3 folds of fine cotton cloth. For getting 1:1 (w/v) ratio 100 ml of distilled water was added with 100 g plant parts. Isolation and identification of Xanthomonas oryzae Bacterial strains were cultured in NA media following strik plate method. After incubation at 30±1 of 48 hrs, individual colony was formed. Thus pure cultures of strains were prepared. Pathogenicity test was done for conformation of the bacterium. Sub cultured strains of bacteria were taken. Five ml sterile water was poured on the bacterial colonies grown in each plate. The suspension was poured in 250 ml Erlenmeyer flask. Bacterial suspensions of 2 strains were taken in test tube. Inoculation was done after 30 days after transplanting of rice seedlings. Plants from each pot was inoculated by cutting leaf tip with a pair of scissors dipped in two test tubes accordingly containing Xanthomonas oryzae pv. oryzae following the method of Kauffman et al. (1973). For control water was used for leaf cutting. After inoculation, reaction was assessed by the following standard evaluation system. According to the Publications, IRRI pathogenicity test is the most reliable to identify Xanthomonas bacteria. The symptom developed in pathogenicity test was characteristic to the symptom of Xanthomonas oryzae pv. oryzae, that s why bacterium was identified as Xanthomonas. In vitro screening of botanicals against Xanthomonas sp. Plant extracts were prepared as previously mentioned method. Millipore filter was used for sterilization. A supply of cotton swabs on wooden applicator sticks was prepared following the method described by Vandepitte et al. (1991). The inhibition zone by two selected botanicals viz. Turmeric rhizom extract and Detura leaf extract against the bacterium was done by well diffusion method (Anon, 1996). Four wells of 5 mm in diameter were made in the same NA plate maintaining equal distance. The broth culture of Xanthomonas sp. was speared uniformly on it with sterile cotton swabs. Plant extracts at definite concentration added into the well each at three replications. In case of control, only sterile water was used instead of plant extracts. The plates were incubated at 30±1ºC. Zone of inhibition around the wells were measured and recorded after every 24 hours for 5 days. Treatments of four different concentrations of turmeric rhizome and datura leaf extract were used. These are T 1 = Control, T 2 = 1:1 (w/b), T 3 =1:2 (w/b) and T 4 =1:4 (w/b). Experimental design and analysis The experiment was conducted following Completely Randomized Design (CRD) with four replications according to ISTA rule (Mathur and Kongsdal, 2003). Data will be analyzed by MSTAT-C computer package program and treatment means will be compared by DMRT. Results and Discussion Pathological properties of two bacterial strains of Xanthomonas oryzae pv. oryzae The both strains showed pathogenic reaction in pathogeniciy test. Leaf area diseased (% LAD) was recorded at 5, 10, 15, 20 and 30 days after inoculation on the variety of Hira-2, BRRI hybrid dhan-2 and SL-8 (Table 2). The maximum leaf area diseased (more than 50%) was observed in SL 8 (Strain 2) and BRRI hybrid dhan 2 (Strain 1) at 30 days after inoculation. The both strains showed positive reaction in all of the varieties of hybrid rice. (Hossain and Azad, 1992) Table 2. Effect of two strains of Xanthomonas oryzae pv. oryzae on the development of BLB disease symptoms in hybrid rice seedlings Variety Strains BLB Severity (%) 5 DAI 10 DAI 15 DAI 20 DAI 30 DAI SL-8 Strain 1 (Whitish) Strain 2 (Yellowish) BRRI hybrid Strain 1 (Whitish) dhan2 Strain 2 (Yellowish) Hira-2 Strain 1 (Whitish) Strain 2 (Yellowish) Indication: - = No symptom, + = Less than 5% leaf area damaged, ++= 5-10% leaf area damaged, +++ = 11-25% leaf area damaged, ++++ = 26-50% leaf area damaged, = More than 50% leaf area damaged, BLB= Bacterial leaf blight and DAI = Days after inoculation Seed health study of hybrid rice by blotter method Findings regarding the incidence of different pathogens in hybrid rice seed are presented in Table 3. The identified pathogens were Xanthomonas oryzae pv. oryzae (two strains), Rhizopus stolonifer, flavus, niger, Fusarium moniliforme, Bipolaris oryzae, Curvularia lunata, Chaetomium globosum and one unknown fungus. It was 63

4 Unknown fungus Curvularia lunata Bipolaris oryzae Chaetomium Globosum Fusarium moniliforme Rhizopus stolonifer Niger flavus Xanthomonas oryzae pv. oryzae (strain 2) Xanthomonas oryzae pv. oryzae (strain 1) App. Sci. Report. 8 (2), 2014: observed that, incidence of Xanthomonas oryzae pv. oryzae strain 1 and strain 2 ranged from 7.35 to 9.54% and 2.5 to 4.55%, respectively. The highest incidence of Aspergilllus flavus and Aspergilllus niger were observed on BRRI hybrid dhan2. The incidence of Rhizophus stolonifer ranged from 1.94 to 4.26% where the highest incidence was recorded on SL 8. The incidence of Fusarium moniliforme ranged from 4.16 to 5.56%. The highest incidence was observed on Hira 2 and lowest on SL 8. The incidence of Chaetomium globosum ranged from 1.46 to 0.71%. The highest Bipolaris oryzae infection was observed on Hira 2 (0.95%) and the lowest was observed on SL 8 and BRRI hybrid dhan2 (0.71%). The incidence of Curvularia lunata recorded from 1.97 to 1.06%. One unknown fungi was also found in all tested verities. Evaluation of different plant extracts against seed borne pathogens of hybrid rice The effect of different plant extracts on pathogen incidence of hybrid rice (Hira 2) is shown in Table 4. The incidence of seed borne pathogens at different treatments was significantly differing from one to another. The highest incidence of Xanthomonas oryzae pv. oryzae strain 1 and 2 were recorded in T 1 and the lowest was recorded in T 7 and T 8. The highest incidence of flavus and niger were recorded in T 1. The highest incidence of Fusarium moniliforme was recorded in T 1 (5.56%) followed by T 2 (4.05%) and the lowest incidence was 0.71% recorded in T 8, T 9 and T 5. The highest incidence of Bipolaris oryzae and Carvularia lunata were observed in T 1 which are 0.95 and 1.79%, respectively. The effect of different plant extracts on pathogen incidence of hybrid rice (SL 8) is shown in Table 5. The incidence of seed borne pathogens at different treatments was significantly differing from one to another. The lowest incidence of Xanthomonas oryzae pv. oryzae was recorded in T 8 and T 10. The lowest incidence of flavus and A. niger were recorded in T 8 and T 7. The highest incidence of Fusarium moniliforme was recorded in T 1 (4.16%) followed by T 6 (2.41%) and the lowest incidence was recorded in T 3, T 4, T 9 and T 10. Carvularia lunata was observed maximum in T 1 (1.06%). The effect of different plant extracts on pathogen incidence of BRRI hybrid dhan 2 is shown in Table 6. The incidence of seed borne pathogens at different treatments was significantly differing from one to another. The highest incidence of Xanthomonas oryzae pv. oryzae strain 1 was recorded in T 1 (9.54%) followed by T 4 (8.42%), T 3 (6.85%) and the lowest incidence was recorded in T 8 (3.29%) followed by T 7 (3.78%). The highest incidence of Xanthomonas oryzae pv. oryzae strain 2 was recorded in T 6 (2.59%) followed by T 1 (2.58%) and the lowest incidence was recorded in T 4 (0.53%) followed by T 10 (0.88%). The highest incidence of Fusarium moniliforme was recorded in T 1 (4.26%) and the lowest incidence was 0.71% recorded in T 8, T 3 followed by T 5. The highest incidence of Chaetomium globosum and Carvularia lunata were observed in T 1 (1.32 and 1.54%, respectively) and 0.71% incidence was recorded in rest of the treatments. Nine plant extracts were evaluated against seed borne pathogens of hybrid rice. All of the botanical were used as per 1:1 (w/b) ratio. From the findings of this experiment, it was reveal that all of the plant extracts significantly control seed borne fungi. Among the plant extracts, four plants extract named, datura leaf extract, turmeric rhizome extract; allamonda leaf extract and garlic clove extract showed best performance against seed borne pathogens of hybrid rice. Kalijira seed extract, bishkatali and shimul leaf extract also showed promising effect against seed borne fungi only. Onion bulb extract did not show efficiency against Fusarium moniliforme and Curvularia lunata. Neem leaf extract did not show significant effect against Fusarium moniliforme and flavus also. Hybrid Rice Varieties Table 3. Percent incidence of different seed borne pathogens on hybrid rice varieties by blotter method % Pathogen incidence Hira b b a a 2.525b a 0.710a a 1.79 ab a SL a a a a a b a a b a BRRI hybrid dhan a b a a 1.947b b a a a a LSD CV% Data were transformed by square root method. 64

5 Unknown fungus Curvularia lunata Bipolaris oryzae Fusarium moniliforme Rhizopus stolonifer Niger flavus Xanthomonas oryzae pv. oryzae (strain 2) Xanthomonas oryzae pv. oryzae (strain 1) Unknown fungus Curvularia lunata Chaetomium globosum Fusarium moniliforme Rhizopus stolonifer Niger flavus Xanthomonas oryzae pv. oryzae (strain 2) Xanthomonas oryzae pv. oryzae (strain 1) Treatments App. Sci. Report. 8 (2), 2014: Table 4. Evaluation of selected plant extract against seed borne pathogen of hybrid rice (Hira 2) Treatments % Pathogen incidence T 1 (Control) a a a a a a a a a T 2 (Onion) a b d b b b b b c T 3 (Kalijira) b b d b b c b b c T 4 (Allamonda) c b d b b c b b c T 5 (Garlic) def b cd ab b c b b c T 6 (Neem) ef b bc ab b c b b b T 7 (Datura) f b cd ab b c b b c T 8 (Turmeric) f b d ab b c b b c T 9 (Bishkatali) cd b b ab b c b b b T 10 (Shimul) cde b bc ab b c b b c LSD CV (%) Data were transformed by square root method. Table 5. Evaluation of selected plant extract against seed borne pathogen of hybrid rice (SL 8) % Pathogen incidence T 1 (Control) a a a b a a a a a T 2 (Onion) bc cd c b b c b b d T 3 (Kalijira) e b c b b d b b b T 4 (Allamonda) b cd c b b d b b cd T 5 (Garlic) cd bcd c b b cd b b cd T 6 (Neem) d bcd b a b b b b bc T 7 (Datura) f bc c b b cd b b cd T 8 (Turmeric) f bcd c b b d b b cd T 9 (Bishkatali) f bcd bc b b d a b bcd T 10 (Shimul) e d c b b d b b cd LSD CV(%) Data are transformed by square root method. 65

6 Unknown fungus Curvularia lunata Chaetomium globosum Fusarium moniliforme Rhizopus stolonifer Niger flavus Xanthomonas oryzae pv. oryzae (strain 2) Xanthomonas oryzae pv. oryzae (strain 1) Treatments App. Sci. Report. 8 (2), 2014: Table 6. Evaluation of selected plant extract against seed borne pathogen of hybrid rice (BRRI hybrid dhan2) % Pathogen incidence T 1 (Control) a a a a a a a a a T 2 (Onion) c abc b b b b b b b T 3 (Kalijira) c bc c b b c b b b T 4 (Allamonda) b c c b b c b b b T 5 (Garlic) d abc c b b c b b b T 6 (Neem) de a c b b b b b b T 7 (Datura) f abc c b b c b b b T 8 (Turmeric) f bc c b b c b b b T 9 (Bishkatali) e ab b b b c b b b T 10 (Shimul) de bc c b b c b b b LSD CV(%) Data are transformed by square root method. Bioassay of Turmeric and Datura extracts against Xanthomonas oryzae pv. oryzae The effect of different concentrations of turmeric rhizome extract were tested against Xanthomonas oryzae pv. oryzae and only T 2 showed inhibition zone in both strain (Table 7). In T 2 after 24 hour no inhibition zone was observed. After 48 hour it was mm, followed by mm after 72 hours, mm after 96 hours and mm after 120 hours. Rest of the treatments showed no inhibition zone. The effect of different concentrations of datura leaf extract were tested against Xanthomonas oryzae pv. oryzae and only T 2 showed inhibition zone in both strain of bacterium (Table 8). In T 2 after 74 hour no inhibition zone was observed. After 96 hour it was mm, followed by mm after 120 hours. Rest of the treatments showed no inhibition zone. Table 7. Comparative efficacy of Turmeric against Xanthomonas oryzae pv. oryzae Inhibition zone Strain 1 Strain 2 Treatment 24hr 48hr 72hr 96hr 120hr 24hr 48hr 72hr 96hr 120hr T 1= Control 0 0 b 0 b 0 b 0 b 0 0 b 0 b 0 b 0 b T 2= 1:1(w/b) a a a a a a a a T 3=1:2 (w/b 0 0 b 0 b 0 b 0 b 0 0 b 0 b 0 b 0 b T 4=1:4 (w/b) 0 0 b 0 b 0 b 0 b 0 0 b 0 b 0 b 0 b LSD CV% Table 8. Comparative efficacy of Datura against Xanthomonas oryzae pv. oryzae Inhibition zone Strain 1 Strain 2 Treatment 24hr 48hr 72hr 96hr 120hr 24hr 48hr 72hr 96hr 120hr T 1= Control b 0 b b 0 b T 2= 1:1(w/b) a 8.333a a 8.333a T 3=1:2 (w/b b 0 b b 0 b T 4=1:4 (w/b) b 0 b b 0 b LSD CV% The present findings were supported previous research reports (Ou, 1972; Fakir and Ahmed, 1974; Hossain and Fakir, 1974; Sharma et al., 1987; Bhutta and Ahmed, 1994). Sharma et al. (1987) detected 10 fungal species of fungi from the rice seeds where Fusarium moniliforme (Gibberella fujikuroi), Curvularia lunata (Cochliobolus lunata), flavus and 66

7 App. Sci. Report. 8 (2), 2014: Rhizopus stolonifer were the most common. Bhutta and Ahmed (1994) reported that maximum seed infection due to Xanthomonas oryzae pv. oryzae was 11% and 12% in variety IRRI-6 at Lahore and Hydrabad, respectively. Mian and Fakir (1989) reported that the most predominant fungi in order of prevalence were Helminthosporium oryzae, Curvularia lunata, Cladosporium cladosporioides, spp. and Trichoconis padwickii. Chowdhury (2005) observed that highly infected/ contaminated seed samples with seed borne fungi of rice, wheat, cosmos, zinnia, sunflower and radish were subjected to seed treatment with 1:0,1:1, 1:5,1:10 and 1:20 dilution of crude/ nascent extract of garlic, datura and turmeric reduced the occurrence of mycoflora on the seed significantly and thereby increased seed germination. Mohanty et al. (1995) reported that garlic bulb extract (1:1) and allamanda leaf extract sprays in the field reduced phomopsis blight and fruit rot by 66% and 75% respectively. Howlader (2003) observed that seed treatment with Allamanda leaf extract (1:1) effectively increased germination of egg plant seeds and tremendously decreased nursery diseases. Ahmed and Sultana (1984) observed that the bulb extract of garlic was most effective against major seed borne pathogens of jute. Seed borne pathogens cause heavy losses to most agricultural crops and difficult to control. Seed treatment with chemical is not eco friendly, expensive and sometime not easily available in local market. Seed treatment with different plant extracts has been shown effective to obtain apparently healthy seed in controlling seed borne fungal pathogen. Rice seed play an important role to carry pathogen. Many pathogen of rice are seed-borne and frequently transmitted through seeds. Thus, one of the efficient means of control of these diseases would be use of pathogen free seed by seed treating agent or seeds with the presence of maximum acceptable limit of the pathogen. Conclusions Among all of the tested botanicals, datura leaf extract and turmeric rhizome extract gave best result against seed borne bacteria and fungi of hybrid rice. Datura leaf extract and turmeric rhizome extract have the highest bactericidal and anti fungal efficacy among the plant extracts used in the experiment. Considering the overall performance, datura leaf extract (1:1 w/b) and turmeric rhizome extract (1:1 w/b) could be used for seed treatment of hybrid rice as an eco friendly approach. However, further intensive study need to be carried out to evaluate the performance of plant extracts at different dilution with different types of organic solvent viz. acetone, ethanol, mineral oil and benzene. 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