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Open Access
MOLECULAR CHARACTERIZATION OF AROID GERMPLASMS OF NORTH EAST INDIA – ASSESSMENT OF HOST RESISTANCE AND BIOLOGICAL MANAGEMENT OF BACTERIAL BLIGHT DISEASE
(2019) Luikham, Star; Bora, L. C.
Bacterial blight disease of Taro incited byXanthomonasaxonopodispv. dieffenbachia (Xad) is a quarantine importance causing extensive damage and loss to the crop in recent decades. The present study was attempted to collect, conserve and characterize the aroid cultivars/ germplasms of North East (NE) India based on 29 RAPD markers, to find out the resistant cultivars/ germplasms amongst them and also in controlling the disease through microbial based biopesticides. 64 Taro cultivars/ germplasm collected from different regions of NE along with two national released varieties,viz.,‘Muktakeshi’ and ‘SreeKiran’ as check varieties were grouped into two main clusters based on RAPD markers.Colony and morphological studies, biochemical and pathogenicity test, Field emission scanning electron microscope (FESEM)and molecular studies confirmed that the pathogen isolated from infected plant parts of colocasia was Xadwhich was short rod-shaped.Screening of the various cultivars/ germplasms against Xadin actual field condition was performed based on the disease severity and disease rating scaleand revealed that the number of resistant, moderately resistant, moderately susceptible and susceptible cultivars were 4, 21, 26 and 15 respectively, while none of the germplasms were immune and highly susceptible to the disease.Disease severity per cent ranged from 14.17 % (Nepali-2) – 67.50 % (SC-1).In vitro studies of the various bioagent combinations for four bio-formulations (Biofor-pf, Bio-time, Biogreen-5, Biozin-PTB) along with streptocycline@100 ppm as chemical check were evaluated against Xad. Highest per cent inhibition (66.22 %) was observed for the combination of five bio-agents, viz., Trichodermaviride, Beauveriabassiana, Metarhiziumanisopliae, Pseudomonas fluorescensandBacillus thuringiensis. Two moderately susceptible germplasms, i.e. ‘Pijayikochu’ and ‘SC-1’ were selected and the four bio-formulations along with streptocycline@100 ppm were evaluated for their efficacy against Xadunder pot condition, by applying these as corm treatment, soil application and foliar spray. Highest disease reduction for ‘Piyajikochu’ (71.42 %) and ‘SC-1’(72.69 %) as well asyield and yield attributing characters were recorded for the bioformulation Biogreen-5 comprising of the five bio-agents while the highest corm and cormels yield (g/plant) recorded were 1194.47 (Pijayikochu) and 1039.06 (SC-1). The present study seems to be the first report for screening of different Taro cultivars/ germplasm against bacterial blight of colocasia under field condition. Exploration of different microbe based biopesticides also seems to be the first report of investigation for controlling the disease.
Open Access
Evaluation of protective strains for cross-protection against Citrus tristeza virus disease
(2019-07) Baruah, Borsha Rani; Nath, P. D.
For Citrus tristeza virus strains differentiation and identification, leaf samples were collected from Khasi Mandarin (Citrus reticulata) plants expressing differential symptoms from three different locations viz., Tinsukia, Golaghat and Mariani of Upper Brahmaputra Valley Zone of Assam. These were then grouped into three categories, viz. low range, medium range and high range based on ELISA OD405 values. Biological indexing with CTV positive samples from these three serological categories on Mexican lime or Kaghzi lime (Citrus aurantifolia) seedlings resulted in symptom expression within three months post grafting. Visible symptoms of CTV infection were observed in some of the graft successful indicator plants whereas, in some plants, no visible symptom development took place within this period. Based on the results, the plants were grouped into two groups- mild and severe, and were confirmed through Bi-directional PCR with mild and severe strain specific primers. PCR products for both mild and severe isolates were sequenced. Consensus sequences showed a single nucleotide difference at position 371 for mild and severe isolates, thereby confirming the identity. Two mild isolates and two severe isolates were selected for the cross protection experiment on Khasi mandarin seedlings. Cross protection experiment was carried out in seven treatments with five replications. Real time-PCR analysis of the grafted plants was carried out six months post grafting to determine the virus titre values through absolute quantification by developing an external standard curve with the equation ‗y = -3.0543x + 37.018‘ (R2 = 0.9981), using 6 serial dilutions of eluted DNA (10-1 to 10-6). The average estimated gRNA copies were 1.02 x 105 + 8.33 x 103 mol/ng and 9.55 x 104 + 5.89 x 103 mol/ng of total RNA in mild inoculated plants, 3.80 x 105 + 3.05 x 104 mol/ng and 3.94 x 105 + 3.53 x 104 mol/ng in severe inoculated plants and, 2.20 x 104 + 2.14 x 103 mol/ng and 3.44 x 104 + 3.20 x 103 mol/ng in mild inoculated plants, later challenged by severe, with no observed amplification in the un-inoculated control. It was observed that the mild inoculated plants, challenged by severe i.e. cross protected plants exhibited the lowest virus copy numbers. Melting curve analysis revealed that the Tm of the mild CTV isolates (80.37–80.820C) was lower than that of the severe isolates (81.57–81.970C). In the cross protected plants, Tm in the range of 80.73-80.880C was recorded, indicating the presence of mild isolates.
Open Access
PURIFICATION, ANTISERA PRODUCTION AND DEVELOPMENT OF DIAGNOSTIC KIT AGAINST POTATO VIRUS Y
(AAU, Jorhat, 2018-07) Mishra, Ranima; Nath, P. D.
Purified viral protein of Potato virus Y (PVY) was isolated from PVY culture maintained on potato (Solanum tuberosum L.) plants. The average concentration of the purified protein was found to be 153.1 ng/ μl with an average yield of 0.449 mg virus per gram of fresh plant tissue. Presence of flexuous filamentous virus particles with an average length of 590 nm in the purified viral suspension was confirmed by Transmission electron microscopy. PVY purified virus preparation was used for immunizing rabbit for production of polyclonal antisera. Good quality antisera were collected one week post boosters (AS4b, AS5b, AS6b and AS7b). The IgG fractions from these four antisera were tested for the detection of PVY by DAS-ELISA with universal anti- rabbit enzyme conjugate as secondary antibody, resulted high specificity with the known PVY infected samples. The assay was compared with the commercial DAS-ELISA kit (Bio Reba, AG, Switzerland). Among the antisera, AS6b was showing the highest mean absorbance value for all positive samples (2.210) which was at par the value shown by the commercial kit (2.250) and these were followed by AS5b (1.680), AS7b (0.929) and AS4b (0.362), respectively. AS6b was showing the highest mean absorbance values for the leaf extracts of samples which were statistically at par with the values shown by the commercial kit. IgG titres for the four batches were measured using a series of IgG dilutions from 10-3 to 10-6 with conjugate and sample dilutions at 10-3 and 100, respectively. Significant differences were observed in the titres of these four batches of IgG at 10-3 dilution. At that dilution, AS6b showed the highest mean absorbance value (1.272) followed by AS5b (1.009), AS7b (0.806) and AS4b (0.522), respectively. In DAS- ELISA with sap dilutions where IgG and conjugate dilutions were constant at 10-3, no significant differences observed in the mean absorbance values of all IgG batches at each sap dilutions and similar trend was observed, among the antisera batches, in sensitivity of IgG towards diluted samples. The AS6b showing the overall highest mean values followed by AS5b and AS7b, respectively. Finally, IgG batch 6b (AS6b) was selected and tested by a simple and rapid tissue/ dot- print immunoassay against PVY. The AS6b showed a highly specific reaction with dot- prints of PVY infected plants at IgG (AS6b) and IgG conjugate dilutions of 10-3. The test was done with sap dilutions of 1:1, 1:2, 1:4, 1:8, 1:16, 1:32 and 1:64 (V/V). AS6b could detect presence of PVY by showing the desired purple coloured reaction up to 1:8 sample dilution. Molecular characterization of PVY from PVY infected samples of Jorhat district, Assam was also carried out through reverse-transcriptase polymerase chain reaction (RT-PCR) assay resulting in desired 328 bp amplicon. Partial sequencing of RT-PCR product and phylogenetic analysis revealed that the virus is closely related to Potato virus Y worldwide isolates.
Open Access
MOLECULAR CHARACTERIZATION OF AROID GERMPLASMS OF NORTH EAST INDIA – ASSESSMENT OF HOST RESISTANCE AND BIOLOGICAL MANAGEMENT OF BACTERIAL BLIGHT DISEASE
(AAU, Jorhat, 2019) Luikham, Star; Bora, L. C.
Bacterial blight disease of Taro incited by Xanthomonas axonopodis pv. dieffenbachia (Xad) is a quarantine importance causing extensive damage and loss to the crop in recent decades. The present study was attempted to collect, conserve and characterize the aroid cultivars/ germplasms of North East (NE) India based on 29 RAPD markers, to find out the resistant cultivars/ germplasms amongst them and also in controlling the disease through microbial based biopesticides. 64 Taro cultivars/ germplasm collected from different regions of NE along with two national released varieties, viz., ‘Muktakeshi’ and ‘Sree Kiran’ as check varieties were grouped into two main clusters based on RAPD markers. Colony and morphological studies, biochemical and pathogenicity test, Field emission scanning electron microscope (FESEM) and molecular studies confirmed that the pathogen isolated from infected plant parts of colocasia was Xad which was short rod-shaped. Screening of the various cultivars/ germplasms against Xad in actual field condition was performed based on the disease severity and disease rating scale and revealed that the number of resistant, moderately resistant, moderately susceptible and susceptible cultivars were 4, 21, 26 and 15 respectively, while none of the germplasms were immune and highly susceptible to the disease. Disease severity per cent ranged from 14.17 % (Nepali-2) – 67.50 % (SC-1). In vitro studies of the various bioagent combinations for four bio-formulations (Biofor-pf, Bio-time, Biogreen-5, Biozin-PTB) along with streptocycline@100 ppm as chemical check were evaluated against Xad. Highest per cent inhibition (66.22 %) was observed for the combination of five bio-agents, viz., Trichoderma viride, Beauveria bassiana, Metarhizium anisopliae, Pseudomonas fluorescens and Bacillus thuringiensis. Two moderately susceptible germplasms, i.e. ‘Pijayi kochu’ and ‘SC-1’ were selected and the four bio-formulations along with streptocycline @100 ppm were evaluated for their efficacy against Xad under pot condition, by applying these as corm treatment, soil application and foliar spray. Highest disease reduction for ‘Piyaji kochu’ (71.42 %) and ‘SC-1’(72.69 %) as well as yield and yield attributing characters were recorded for the bioformulation Biogreen-5 comprising of the five bio-agents while the highest corm and cormels yield (g/plant) recorded were 1194.47 (Pijayi kochu) and 1039.06 (SC-1). The present study seems to be the first report for screening of different Taro cultivars/ germplasm against bacterial blight of colocasia under field condition. Exploration of different microbe based biopesticides also seems to be the first report of investigation for controlling the disease.
Open Access
BIOINTENSIVE MANAGEMENT OF SHEATH ROT DISEASE OF RICE CAUSED BY Sarocladium oryzae (SAWADA) GAMS AND HAWKSW
(AAU, Jorhat, 2019-07) Bora, Budha; Ali, Sakendar
Sheath rot of rice caused by Sarocladium oryzae (Sawada) Gams and Hawksw has emerged as one of the major diseases of rice. The fungus attacks the boot leaf sheath affecting emergence of panicle resulting discoloured and chaffy grains and inflicts considerable yield loss. The pathogen is seed borne and survives in soil on the leftover stubbles, which acts as the sources of primary inoculums. Many effective pesticides have been recommended against this disease, but not considered as a long term solution because of concerns about pesticide residue risk, health and environmental pollution and health hazards, development of resistance, residue persistence and elimination of natural enemies which necessitates an alternative eco-friendly method for its management and sustainable crop production. The present study was undertaken to evaluate the integrated effect of microbial antagonist, organic amendments and biofertilizer consortia on the suppression of sheath rot pathogen that survives in rice seeds, stubbles and consequential improvement of soil health. Among the different microbial antagonists evaluated, Pseudomonas fluorescens was found to be the most effective inhibiting maximum (82.06%) radial growth of S. oryzae in vitro followed by Bacillus subtilis (7.35%) and B.megatorium (67.38%), respectively. Among the fungal antagonists, Trichoderma harzianum was found to be the most efficient inhibiting maximum (65.21%) radial growth of S. oryzae followed by T. viride (57.76%) and T. asperellum (52.09%), respectively. Talcum powder based formulation of the best microbial antagonist (P. fluorescens) was found to be most effective when applied as seed treatment, seedling root dip treatment and foliar spray at boot leaf stage in reducing maximum disease incidence (68.24%) and percent disease index (57.26%) over control and increased the yield attributing characters such as number of effective tillers per hill, number of healthy grains per panicle, 1000 grain weight and grain yield etc tested under pot condition. Dhaincha (Sesbania aculeata) as organic amendment along with biofertilizer consortia enriched FYM and microbial antagonist (P. fluorescens) was proved to be the most effective method for management of sheath rot disease as evidenced by maximum reduction of disease incidence (69.94%) and percent disease index (60.95%) over control and also found to increased the yield attributing characters under field condition. The S. oryzae could survive only upto 120 days in S. aculeata amended plot followed by 150 days in plots amended with azolla and vermicompost, respectively whereas, it could survive upto180 days in the control plot at different soil depths (0cm, 2 cm and 4 cm) that were evaluated. However, in all the situations, the survival and viability of S. oryzae declined with increase in time. Soil amendment with organic materials along with biofertilizer consortia and microbial antagonist (P. fluorescens) has significantly increased the N, P, K content, organic carbon and microbial biomass carbon. Among all the organic amendments, S.aculeata as in situ green manure crop along with biofertilizer consortia and microbial antagonist(Pf) was found to increase maximum N, P, K (305.4, 17.77, 106.43 kg/ha) content of soil and ranked next to RDF. Moreover, organic amendments have significantly increased the Boron content of soil. Among all the organic amendments, the plot amended with S.aculeata along with biofertilizer consortia and microbial antagonist (Pf) recorded the highest (0.66 mg/kg) B followed by azolla (0.64 mg/kg) and vermicompost (0.63 mg/kg) plot, respectively. Among all the different amendments, S.aculeata as in situ green manure crop along with biofertilizer consortia and microbial antagonist (Pf) recorded the maximum OC and MBC (0.67%, 281.58μg/kg) followed by azolla (0.63%, 273.46 μg/kg) and vermicompost (0.61%, 267.88 μg/kg) plot, respectively. The enhancement of OC and MBC in the dhaincha amended plot over control was recorded to the tune of (23.88%) and (12.86%), respectively and considered as the most effective treatment combination not only in terms of improvement of plant health, soil health and disease suppression ability but also found to enhance the grain yield.
Open Access
MOLECULAR CHARACTERIZATION OF AROID GERMPLASMS OF NORTH EAST INDIA – ASSESSMENT OF HOST RESISTANCE AND BIOLOGICAL MANAGEMENT OF BACTERIAL BLIGHT DISEASE
(AAU, Jorhat, 2019) Luikham, Star; Bora, L. C.
Bacterial blight disease of Taro incited by Xanthomonas axonopodis pv. dieffenbachia (Xad) is a quarantine importance causing extensive damage and loss to the crop in recent decades. The present study was attempted to collect, conserve and characterize the aroid cultivars/ germplasms of North East (NE) India based on 29 RAPD markers, to find out the resistant cultivars/ germplasms amongst them and also in controlling the disease through microbial based biopesticides. 64 Taro cultivars/ germplasm collected from different regions of NE along with two national released varieties, viz., ‘Muktakeshi’ and ‘Sree Kiran’ as check varieties were grouped into two main clusters based on RAPD markers. Colony and morphological studies, biochemical and pathogenicity test, Field emission scanning electron microscope (FESEM) and molecular studies confirmed that the pathogen isolated from infected plant parts of colocasia was Xad which was short rod-shaped. Screening of the various cultivars/ germplasms against Xad in actual field condition was performed based on the disease severity and disease rating scale and revealed that the number of resistant, moderately resistant, moderately susceptible and susceptible cultivars were 4, 21, 26 and 15 respectively, while none of the germplasms were immune and highly susceptible to the disease. Disease severity per cent ranged from 14.17 % (Nepali-2) – 67.50 % (SC-1). In vitro studies of the various bioagent combinations for four bio-formulations (Biofor-pf, Bio-time, Biogreen-5, Biozin-PTB) along with streptocycline@100 ppm as chemical check were evaluated against Xad. Highest per cent inhibition (66.22 %) was observed for the combination of five bio-agents, viz., Trichoderma viride, Beauveria bassiana, Metarhizium anisopliae, Pseudomonas fluorescens and Bacillus thuringiensis. Two moderately susceptible germplasms, i.e. ‘Pijayi kochu’ and ‘SC-1’ were selected and the four bio-formulations along with streptocycline @100 ppm were evaluated for their efficacy against Xad under pot condition, by applying these as corm treatment, soil application and foliar spray. Highest disease reduction for ‘Piyaji kochu’ (71.42 %) and ‘SC-1’(72.69 %) as well as yield and yield attributing characters were recorded for the bioformulation Biogreen-5 comprising of the five bio-agents while the highest corm and cormels yield (g/plant) recorded were 1194.47 (Pijayi kochu) and 1039.06 (SC-1). The present study seems to be the first report for screening of different Taro cultivars/ germplasm against bacterial blight of colocasia under field condition. Exploration of different microbe based biopesticides also seems to be the first report of investigation for controlling the disease.
Open Access
Potentiality of Banana endophytes from Assam against Fusarium oxysporum f.sp. cubense
(AAU, Jorhat, 2019-07) Kumar, Savani. Ajit; Bhattacharyya, Ashok
In the present study an attempt was made to study the potentiality Banana endophytes from Assam against Fusarium oxysporum f.sp. cubense, the causal organism of Fusarium wilt of banana. A total of 300 banana samples from leaf, pseudo-stem and root were collected from different agro-climatic zones considering season, topography and type of cultivars for isolation of endophytes. Present Investigation revealed that highest number of endophytic microflora was recorded during monsoon season (May to September) where as lowest number of endophytic microflora during post monsoon season (October to December).Tissue specificity studies resulted highest number of endophytic microflora in root tissue samples used. Of the 330 endophytes were isolated from 300 samples only three endophytic microbes (2 fungi and 1 bacteria) found to be most antagonistic against Foc. The promising endophytes based on in vitro studies and PGP index, were further studied for their efficacy in reducing the vascular wilt incidence under in vivo (pot culture) and the combination treatment of all the three microbes was most effective in reducing the vascular wilt. A positive correlation of biometrical parameters of banana plant such as height, girth, number of leaves and number of roots was also observed with the treatment of combinations of three microbes In assessing AUDPC and rate of infection (r) plants inoculated with combination treatments were significantly effective in reduction of disease with 99. 9 units2 and with an epidemic rate at 0.02 units d-1.The three most promising endophytic microbes were further considered for cultural, morphological and molecular studies. The 18S rRNA sequencing of ITS1 and ITS4 region of the genome revealed that the first and the second best promising endophytic microbes were Trichoderma reesei, Rigidiporus vinctus while the third best promising endophytic microbe was Sphingobacterium tabacisoli. Study on the different modes of action of the promising endophytes revealed that all endophytes were able to produce volatile and non-volatile compounds, IAA, NH3, siderophore and HCN, though at different levels. However, Sphingobacterium tabacisoli failed to solubulize phosphate on solid medium containing insoluble inorganic phosphorus source. On the other hand, Sphingobacterium tabacisoli failed to produce non-volatile compounds, sidherophore, but the endophytes could produce different levels of extracellular enzymes and can tolerate different levels of salt concentrations. The result of the biochemical test revealed that there was a higher activities of different defence related enzymes viz. peroxidase, polyphenol oxidase, phenylalanine ammonia lyase in plants inoculated with endophytic combinations as compared to single endophytes treatments after inoculation with Foc. The result of the present investigation suggested that the higher activity of these enzymes is an indicative for activation of innate plant immunity by application of endophytes combinations.
Open Access
DEVELOPMENT OF IPDM MODULE FOR CULTIVATION OF BRINJAL
(AAU, Jorhat, 2018-01) Upamanya, Gunadhya Kumar; Dutta, Pranab
Brinjal growers of Assam completely depend on the chemocentric cultivation practices to combat harmful pests and diseases, which not only increase the cost of cultivation but also affect consumers with pesticide residues. Moreover, the indiscriminate use of chemical pesticides, fertilizer etc. also causes harm to the environmental matrix. Development of an alternative eco-friendly IPDM module for sustainable production of the crop is the need of the hour. The present study was done on development of a consortia of phytopathogenic biocontrol agent, entomopathogens together with application of the consortial formulation biofertilizers with an aim to get a combine effect against diseases, pests and simultaneously supply of major nutrients for organic cultivation of brinjal. In vitro dual culture study showed that out of six (6) biocontrol agents T. harzianum showed marked inhibition against Rhizoctonia solani (74.44%), Fusarium solani (70.68%), Alternaria melongenae (72.48%), Sclerotinia sclerotiorum (69.15%) and Phomopsis vexans (77.82). In another in vitro study done in pot condition, M. anisopliae (@1X10 8 spores/ml of water) was found better in reduction of population of sucking pests like aphid (64.87%), jassid (57.74%), and white fly (63.80%). On the other hand, B. bassiana was found better for hadda beetle with 67.16% reduction in population. B. bassiana was also found to be the superior in reduction of brinjal shoot and fruit borer (per cent shoot infestation=9.34, Percent fruit infestation by number=11.73 and by weight=14.32). Compatibility study done by coculture method showed that amongst the tested biocontrol agents, T. harzianum and two entomopathogens viz., B. bassiana and M. anisopliae were found to be compatible. Based on the in vitro study a liquid consortial formulation with three best biocontrol agents viz., T. harzianum, B. bassiana and M. anisopliae was prepared with already standardized additives (Department of Plant Pathology, AAU, Jorhat). Shelf life study showed that the consortia can retain 45% viability up to 6 months at room temperature and up to 54% at 40C and 64% viability at -200C for a year. Pot and field experiment conducted at Mycology Research Section and organic block of Experimental Farm, Department of Horticulture, AAU during 2014-15 to test the efficacy of six different IPDM modules showed that module-6 (seed treatment + seed bed treatment in nursery + soil application in main field + seedling dip treatment with consortia of biofertilizer, Rhizobium sp, Azotobacter sp strain 52, Azospirillum sp strain 71 and Bacillus sp strain 5 W + spraying of BCA) was the best in the management of pests (aphid, jassid, hadda beetle and brinjal shoot and fruit borer) and diseases (Phomopsis leaf blight and fruit rot, Alternaria leaf spot, Fusarium wilt) of brinjal. Field experiment was conducted at KVK, Barpeta during 2015-16 to study the efficacy of the six modules against pest and disease management and growth parameters of brinjal and module 6 was found best for controlling pest and disease incidence with increased growth parameters and yield of the crop. Result of pooled analysis of field experiment showed an yield of 570.97 q/ha with B:C ratio 3.99. The module was also found effective in improving the nutrient status with significant increase of P and K status of soil and with microbial biomass carbon in both the years of experiment (2014-15 and 2015-16). Further, the module was tested in farmer’s field as OFT and comparison was made with farmer’s practice i.e, use of cypermethrin 10% EC and carbendazin 50% WP and chemical fertilizer @ NPK 50:50:50 kg/ha. Result showed that the developed IPDM module can curb the pests and disease complex of brinjal with farmer’s practice (application of chemical pesticides). An yield of 442.10 q/ha with B:C ratio of 3.48 was obtained in the best module which was at par with the farmer’s practice (yield= 449.56 q/ha and B:C ratio= 3.12). Post treatment nutrient status and physical properties of soil was found statistically non significant except the status of P which was significantly higher in farmer’s practice. However, the soil microbial biomass carbon was found statistically superior in the tested module (834.10 μg/g of soil) over farmer’s practice (351.74 μg/g of soil) and control (362.56 μg/g of soil).The module can be used by farmers for organic cultivation of brinjal after multilocational field trial in different agroecological condition of Assam.
Open Access
REACTION OF AROMATIC AND GLUTINOUS RICE GENOTYPES AGAINST SHEATH ROT (Sarocladium oryzae) DISEASE AND ITS MANAGEMENT WITH IDM MODULE
(AAU, Jorhat, 2017-07) Singh, Manjay; Das, B. C.
Sheath rot of rice caused by Sarocladium oryzae (Sawada) Gams and Hawksworth, has gained the status of major disease of rice, and yield losses varies from 9.6 to 85%. The present investigation was under taken to identify the resistant genotypes/cultivars as a donor gene for the development of HYV and to evaluate the efficacy of different IDM Modules for management of sheath rot of rice. The sheath rot disease sample was collected from the rice field of Regional Agriculture Research Station, Titabar. The isolates were cultured, purified and mass culture was prepared in half boiled rice grain, and single grain insertion method was followed for inoculation in aromatic and glutinous rice genotypes/ cultivars. Among the genotypes/ cultivars that were screened, eight entries showed resistant reaction from aromatic rice and five entries showed resistant reaction from glutinous rice genotypes/ cultivars. The physiological parameters were evaluated in both resistant and susceptible genotypes/ cultivars of both aromatic and glutinous rice. The resistant entries possess a higher concentration of phenol, protein and lower concentration of starch and sugar as compared to the susceptible one. The total phenol concentration was increased in, Resistant (R), Moderately resistant (MR), Moderately susceptible (MS) and decreased in susceptible genotypes/ cultivars after infection. Similarly, protein, starch, and TSS were found to be decreased in all the categories of genotypes/ cultivars (R, MR, MS, S). However, maximum reduction was observed in susceptible genotypes/ cultivars after infection. The interaction among the stem attacking fungal pathogens showed that Sarocladium oryzae suppresses the growth of Rhizoctonia solani and Sclerotium oryzae. in both in vitro and in vivo, while Sclerotium oryzae was more sensitive against Sarocladium oryzae as compared to Rhizoctonia solani. Among the modules that were evaluated for management of sheath rot disease of aromatic and glutinous rice. PDI and PDS were significantly reduced and increase of growth parameters and yield, in the entire module as compared to the inoculated control. However, the maximum reduction of PDI, PDS and increase of growth parameters and yield were recorded in Module- 2, where seeds were treated with carbendazim @ 2g/ kg of seed, soil application of Pseudomonas fluorescence @ 2.5kg/ha (2.5kg +50kg FYM) and 50% of potash of recommended dose at tillering stage along with Foliar spray with Carbendazim @ 0.2% after 30 days of transplanting and Foliar spray with Bioveer @ 2% at booting stage.

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