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2020 - 202121
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Subject: Plant Pathology × End date: 2021 × Start date: 2020 × Type: Thesis ×
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    ThesisItemOpen Access
    Studies on the nematicidal effect of Ammonium bicarbonate and lime against Meloidogyne incognita (Kofoid and White, 1919) Chitwood, 1949 on tomato (Lycopersicon esculentum Mill.)
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Patil, Prashant; Rawat, Shilpi
    Tomato (Lycopersicon esculentum) is an important vegetable in India but its productivity is very low (214.5 q/ha), compared to the developed countries, and this can be attributed to the vulnerability of tomato crop to various diseases including fungal, bacterial, viral and nematode diseases. Among the above diseases, Root-knot nematodes are the major pathogens of vegetable crops and are responsible for causing huge yield losses every year in heavily infected crops. Meloidogyne incognita deteriorates the quality of fruit and thereby causing yield losses of 30 to 40% of tomato crop. The experiment was carried out during the year 2019 and 2020 at Department of Plant Pathology, Collage of Agriculture, G. B. Pant University of Agriculture and Technology Pantnagar. Laboratory study on identification of M. incognita resulted with important findings based on morphological characterization of species. The experiment conducted to study the effect of different inoculum level viz, 250, 500, 1000, 2000, 4000 and 8000 second stage larvae of M. incognita on various growth parameters of tomato showed significant reduction at the inoculums level of 500 J2 per kg of soil and above. Damaging threshold level at inoculum level of 2000 J2 per kg of soil and maximum reduction at 8000 J2 per kg of soil has been observed in tomato cv Pant T-3. Experimental results of in vitro evaluation of compounds on egg hatching of M. incognita showed, rate of egg hatching was directly proportional to time period and inversely proportional to concentration of compounds used. AB+L @ 10.0 per cent concentration at the end of 120 hours exposure period was most effective as compared to other compounds. Similarly, in vitro evaluation of effect of compounds on mobility of J2 of M. incognita showed that immobility of second stage larvae was found directly proportional to time period and concentration of chemical compounds. Among all the treatments, AB+L @ 10.0 per cent concentration caused maximum per cent immobility of second stage larvae. Under glass house condition, among three compounds tested which exhibited nematicidal effect on nematode population and galls clearly revealed that the AB+L were found most effective at 3.0g /kg of infected soil followed by its lower concentration of 2.25g/kg of infected soil. AB at 1.0g/kg of infected soil and lime at 2.0 g/kg soil of concentration perform better than control. With respect to chemical properties i.e. soil pH, organic carbon and available nitrogen on nematode suppression, AB+L increased the soil pH, organic carbon and available nitrogen suppressing the nematode population followed by AB which increases both nitrogen and organic carbon and lime which increased only pH. However, all the compounds at all the concentrations suppressed the nematode population and increase the plant growth as compared to check. Thus, it can be said that Ammonium bicarbonate and Lime (AB+L) has the potential of a nematicide.
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    ThesisItemOpen Access
    Development of biofortified oyster mushroom (Pleurotus spp.) using Zinc Sulphate nanoparticle
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-11) Shivani; Kushwaha, K.P.S.
    Pleurotus spp. commonly known as oyster mushroom in english and Dhingri in hindi, is one of the most important edible mushrooms cultivated in all around the world and is rich in nutritional as well as medicinal properties. Zinc is an essential trace element next to iron and its deficiency can lead to growth retardation, loss of appetite, and impaired immune function. Since the human body does not store excess zinc, it must be consumed regularly as part of the diet. Biofortification of food crops for increasing the zinc content and its bio-availability is one of the potential alternatives for combating zinc deficiency. The present study pertains to the development of zinc bio-fortified Pleurotus spp. (P. sajor-caju, P. florida and P. flabellatus) using zinc sulphate nanoparticles (ZnSO4 NPs). Zinc sulphate nanoparticles was sprayed at different concentrations (10 ppm, 20 ppm, 30 ppm and 40 ppm) after complete spawn run and nutritional and antioxidant properties of the fruiting bodies were analysed. The maximum mycelial radial growth and growth rate per day (mm) was obtained in all the tested species of Pleurotus at 10 ppm concentration of ZnSO4 NPs. Moreover, there was maximum increase in the growth parameters (pileus width, stipe length and stipe width), total yield and biological efficiency was obtained at10 ppm concentration of ZnSO4 NPs of as compared to the control. The highest increase in zinc content was obtained in 40 ppm concentration of ZnSO4 NPs i.e., 115.63% in P. sajor-caju followed by P. flabellatus (113.58%) and P. florida (106.35%). Similarly, at 40 ppm concentration of ZnSO4 NPs the phenol and flavonoid content was also found maximum. Whereas, the highest sodium and potassium content was bioaccumulated at 10 ppm concentration. The nutritional status of Pleurotus spp., measured in terms of crude protein, total ash and total soluble sugars, was found highest at 10 ppm concentration. The maximum increase in DPPH, ABTS and FRAP radical scavenging activity was observed at 10 ppm concentration of zinc sulphate nanoparticle. In case of, DPPH radical scavenging activity the highest increase was observed in P. sajor-caju followed by P. flabellatus and P. florida. Whereas, in case of ABTS radical scavenging activity the highest increase was obtained in P. sajor-caju followed by P. florida and P. flabellatus. Furthermore, in case of FRAP radical scavenging activity the highest increase was obtained in P. flabellatus followed by P. sajor-caju and P. florida. Therefore, Pleurotus spp. when biofortified with zinc sulphate nanoparticle at 10 ppm concentration has positive effect on the mycelial growth, biological efficiency, growth parameters, bioaccumulation of micronutrients, nutritional as well as antioxidant activities of Pleurotus spp. Thus, 10 ppm ZnSO4 NPs can be used for getting maximum yield of oyster mushroom and to combat zinc deficiency.
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    ThesisItemOpen Access
    Development of Iron–biofortified button mushroom (Agaricus bisporus) using nanoparticle
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-08) Singh, Omkar; Kushwaha, K.P.S.
    Nutrient deficiency is one of the major global health problem, with iron deficiency being a leading cause of many ailments. Amongst several approaches that have been tried to combat this problem, use of bio-fortified foods is one of the most promising one. It not only increases the intake of nutrient but also augments its bioavailability. Mushrooms have been a source of good nutrition since ancient times; among which Agaricus bisporus is a widely consumed species. Due to its high nutritional value, but relatively low iron content, an attempt was made in the present investigations to developed iron bio-fortified Agaricus bisporus, using iron oxide and iron sulfide nanoparticles. Different concentrations of iron nanoparticles (0, 3, 6, 9, 12 and 15 ppm) were used to supplement the mushroom at three different stages i.e at spawning stage, before casing stage and pin head initiation stage. Treated mushroom was analyzed for various attributes viz. mycelial growth, crop yield, iron content, sensory evaluation and antioxidant activity. Highest mycelial growth, crop yield and iron content were obtained in 9ppm in case of iron oxide and at 12 ppm in case of iron sulfide nanoparticle treated Agaricus bisporus. The antioxidant status measured in terms of flavonoid and phenol content was also recorded to be highest in 9ppm in and 12 ppm treated samples respectively. Phenol content increased with increasing concentration of iron nanoparticles, with 15ppm having maximal content. Proline and hydrogen peroxide content decreased continuously from 0 to 15 ppm. Thus from the above investigations it can be concluded that use of nano-biotechnology could be an efficient way to bio-fortify Agaricus bisporus along with enhanced iron and antioxidant activity.
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    ThesisItemOpen Access
    Utilization of spent mushroom compost by enrichment of biocontrol agents for the management of collar rot disease in bottle gourd
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Kansal, Surbhi; Sharma, Roopali
    Among cucurbits, bottle gourd (Lagenaria siceraria (Mol.) Standl.) is one of the oldest vegetable grown in tropical and subtropical parts of the world. In the recent years, collar rot caused by Macrophomina phaseolina is becoming more prevalent in Tarai region of Uttarakhand where climate change is leading to high temperature. Collar rot infected bottle gourd seedlings exhibited reddish brown discoloration on emerging hypocotyl near the soil line extending up to the stem. Later these lesions coalesce and resulted into complete wilting and pre mature death of the plants. Therefore, it is important to manage this disease. Since bottle gourd is directly consumed after its harvest, so the intensive use of fungicides is very harmful to human health. Consequently, one of the main problems faced by mushroom industry is finding a sustainable way for proper disposal of the Spent Mushroom Compost (SMC), which is the leftover waste that remains after harvesting mushroom fruiting bodies and about 17 million tons of spent mushroom substrate, is produced each year. This SMC can be exploited to improve soil quality and for the suppression of soil borne diseases. Keeping in view of public health as well as environmental safety, it is high time to incorporate the use of SMC amended with potential biocontrol agents as an important component of Integrated Disease Management (IDM). In the present investigation, attempts were made to utilize SMC enriched with potential biocontrol agents for the management of collar rot disease, caused by Macrophomina phaseolina in bottle gourd. In vitro assays revealed that both Trichoderma harzianum (Th-14) and Pseudomonas fluorescens (Pf-173) inhibited the growth of fungal pathogen by 74.27 and 66.66 per cent respectively in dual culture and 86.00 and 70.83 per cent respectively in volatile assay. The glasshouse experiment was conducted where different proportions of SMC and Pant bioagent-3 (Trichoderma harzianum + Pseudomonas fluorescens) were amended with soil. The soil was artificially inoculated with M. phaseolina in pot culture. While analyzing the effect of SMC at different proportions, it was observed that a combination of SMC + Pant bioagent-3 (75%) amended with 25% of soil showed good results with minimum disease incidence (17.03 per cent), higher seed germination (96.67 per cent), plant vigour index (17429.60) and other growth parameters such as root length (22.94 cm) and shoot length (157.36 cm) and fresh weight (33.40 g and 5.16 g) and dry weight (6.76 g and 2.16 g) of shoot and root respectively. Thus, SMC enriched with biocontrol agents can be utilized as an effective soil conditioner because of its ability to significantly suppress the disease and enhance the growth of the plant.
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    ThesisItemOpen Access
    Assessment of spent mushroom substrate against early blight, growth and yield of potato
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Panda, Somananda; Mishra, S.K.
    Spent mushroom substrate (SMS) is the left over product after mushroom harvest. It is rich in both macro, micronutrients and also the sink of various beneficial saprophytic micro-organisms including fungi. The SMS increases the plant vigour as well as induces their disease resistance. Keeping this importance of SMS in view, the present research experiments were carried out in the lab, field and glasshouse to control early blight of potato caused by Alternaria solani. These experiments with ten foliar applications of 10%, 20%, 30% and 40% extract of the SMS of both Agaricus bisporus (E-SMS-Ab) and Pleurotus ostreatus (E-SMS-Po) including mancozeb and control. The EC, N, P, K, Fe, Mn, Cu and Zn were found high in quantity in E-SMS-Ab than the ESMS- Po and thus both were act as a growth promoter of Alternaria solani in-vitro. However, in the treatment of E-SMS-Po-40%, highest 13.67 CFUs of phylloplanes (Trichoderma, Aspergillus and Actinomycetes) were counted. In the field condition, the effect of E-SMS-Ab-40%, E-SMS-Po-40% and mancozeb-0.25% were found at par and controlled the disease severity by 37.03, 38.27 and 40.74%, respectively over control. While, increased plant height, foliage fresh and dry weight and yield of potato were recorded in the treatment of both the SMSs of 40 % each than to that of mancozeb and control. Out of ten treatments of the glasshouse, the pot mixture of four treatments of ESMS- Ab were additionally made rich by mixing 10%, 20%, 30% and 40% of SMS-Ab along with above foliar application of the SMSs. The pot treatment represent 40% soil-foliar application and mancozeb-0.25% were stood with least 30.67 and 28.67% disease severity, respectively. However, the cumulative effect of 40% soil-foliar application of SMS-Ab was invariably excellent in obtaining increased germination percent (83.57 %), plant height (78.47 cm), fresh weight (82 g), dry weight (26.67 g) and tuber weight (77.17 g). The above results were clearly stated that the foliar application of both the SMSs demonstrated dual effects on the plants by 1) increasing their vigour and resistance and 2) reduced the disease severity upon the activation of Trichoderma, Aspergillus and Actinomycetes from the potato foliage. Additionally, the soil and foliar application of ESMS-Ab further encouraged the above results. Therefore, it could be concluded that, both the SMSs more or less effective and used as an alternate source for managing the early blight of potato and its pathogen Alternaria solani under field and glasshouse condition. In future, the improved and concentrate form of the SMSs may be used in increasing plant vigour and their disease resistance.
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    ThesisItemOpen Access
    Cultural variability and germplasm screening against Bipolaris sorokiniana (Sacc.) Shoemaker causing spot blotch disease in bread wheat (Triticum aestivum L.)
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Nautiyal, Ananya; Deepshikha
    Wheat (Triticum aestivum L.) is one of the most nutritious and basic staple food crop and is widely cultivated cereal grain in the world. In India spot blotch disease caused by Bipolaris sorokinana (Sacc.) Shoemaker is reported to be important foliar disease causing yield loss ranging from 15-50 per cent. It is one of the most important diseases of wheat in North Eastern Plains Zone (NEPZ) representing warm and humid climate in India. Spot blotch was earlier thought to be minor disease but due to global climate change it is also increasing in North Western Plains Zone (NWPZ), Peninsular and Central zone of India. The present investigation was carried out with following objectives: (i) Screening of wheat germplasm against spot blotch for identification of sources of disease resistance under epiphytotic conditions. (ii) Study the role of agronomic traits on spot blotch resistance resistance (iii) Assessment of Area Under Disease Progress Curve (AUDPC) and Infection rate (iv) Study the Cultural- morphological variability of Bipolaris sorokiniana under in-vitro condition. The study was conducted during 2019-20 and 2020-2021 and the experimental material comprised of 192 germplasm accessions along with four checks, Chirya 3 and Francolin (resistant) HD3086 & HD2967 (susceptible). The fifty three germplasm accessions out of 192 were found to be phenotypically resistant and had lower AUDPC values. Therefore, selection of cultivars having lower AUDPC values is acceptable for practical purposes. These genotypes were evaluated in randomized block design (RBD) in 2020-2021 and observations were recorded for six characters viz., disease severity, days to 75% heading, days to maturity, plant height, spike length and thousand grain weight. Simultaneously, correlation analysis of these agronomic traits revealed that days to maturity, days to heading, plant height were negatively correlated with AUDPC whereas, spike length and test weight were positively correlated. The pathogen Bipolaris sorokiniana was isolated from the leaf samples collected from eight locations in Uttarakhand (Pantnagar, Sitarganj, Khatima, Nanakmatta, Kashipur, Rudrapur, Gadarpur and Haldwani). The cultural and morphological studies of these isolates were done under in-vitro conditions, which revealed a distinct variation in colony morphology as well as conidial characteristics in all the eight isolates. The information on cultural and morphological variability existing in the pathogen (Bipolaris sorokiniana) can be utilized by breeders and pathologists for resistance breeding and the aggressive isolates can be used for creating epiphytotic conditions. The resistant accessions can be used by breeders for the development of spot blotch resistant varieties.
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    ThesisItemOpen Access
    Molecular characterisation of tomato leaf curl disease and its vector (Bemisia tabaci Genn.) in tarai region of Uttarakhand
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Rakhonde, Gaurav Yashwant; Singh, K.P.
    Tomato is attacked by a wide range of pathogens throughout the cropping season and among them, Tomato leaf curl virus is one of the most important threat to the crop. The disease was characterized as typical leaf curling, crinkling, stunting, puckering, reduced flowering and fruiting. The highest mean disease incidence of the disease was observed in 2020 while severity was recorded maximum in 2021. The mean disease incidence was varied from 68.76 to 67.19 per cent and severity from 26.60 to 27.14 per cent in the year 2020 and 2021, respectively having maximum overall incidence and severity in Nainital district. No significant difference was found between the disease incidence and severity in the Tarai region during two years of study. Disease severity was found to show highly significant positive correlation with disease incidence (r =0.865). The morphological study through the electron microscope revealed that ToLCV particles have twin geminate particles measuring 30 x 20 nm. Vector transmission study revealed that whitefly serve as vector for the transmission of virus. The PCR amplification was done using the primers RUGEMF1 and RUGEMR1 followed by sequencing which revealed that more than 97 per cent similarity with ToLCNDV isolates and partial CP sequence was deposited in NCBI Gene bank database under accession number MZ781422. The highest pairwise identity was obtained with ToLCNDV isolate BG14 coat protein gene (98.40%) reported from India (MN527536). Based on high sequence identities and phylogenetic relationships of partial DNA-A genome with ToLCNDV isolates, the Begomovirus isolate under study was identified as an isolate of Tomato leaf curl New Delhi virus and designated as ToLCNDV_[Pant]. Amplification and sequencing of the partial mtCo1 gene of Bemisia tabaci collected from the Tarai revealed that all samples belonged to the Asia-II-1genetic group. Overall mean pair wise distance was among the 10 sequences under study was 0.0139 while that of reference Asia-II-1 varied between 0.0031 to 0.0332. The sequencing data generated in the current study was submitted to the NCBI database and accession numbers were acquired (MZ778803 to MZ778812). The present study will help in establishing an integrated approach in ToLCD management.
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    ThesisItemOpen Access
    Status and distribution of root knot nematode (Meloidogyne spp.) and other major plant parasitic nematodes associated with kiwi (Actinidia deliciosa chev.) in Kumaon region of Uttarakhand
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Veratiya, Arun Kumar; Satya Kumar
    Kiwi is the most important horticulture crop of Uttarakhand. It plays a significant role in the economy of Uttarakhand. Plant parasitic nematodes are one of the limiting factors in kiwi production which results in quality deterioration and yield loss. Keeping this view, an extensive survey was conducted in four districts of Kumaon region of Uttarakhand to study the status of important plant parasitic nematodes associated with kiwi. Soil samples were collected from different locations of the districts and analysis was done in Nematology Laboratory of Department of Plant Pathology, Govind Ballabh Pant University of Agriculture & Technology, Pantnagar. Analysis revealed the presence of eight genera of plant parasitic nematodes associated with kiwi viz., Meloidogyne spp., Helicotylenchus spp., Aphelenchus spp., Criconemoides spp., Pratylenchus spp., Tylenchus spp., Ditylenchus spp. and Tylenchorhynchus spp. Among these Meloidogyne spp. was predominant in all the four districts surveyed viz, Almora, Champawat, Nainital and Pithoragarh. From Almora district, Majkhali showed highest population of plant parasitic nematodes and was affected maximum with RKN both in terms of soil (200cc) and roots (per gram) with total population (1820). From Champawat district, Suie showed maximum population of plant parasitic nematodes and was affected maximum with RKN both in terms of soil and roots with total population (2603). In Nainital district, Satbunga showed maximum population of plant parasitic nematodes whereas Kashiyalekh was affected maximum with RKN both in terms of soil and roots with total population (2020). In Pithoragarh district, Aincholi showed maximum population of plant parasitic nematodes and affected maximum with RKN both in terms of soil and roots with total population (2747). Aincholi in Pithoragarh district was maximum affected by RKN among all the locations surveyed. Presence of two Meloidogyne spp. were found i.e., Meloidogyne incognita and Meloidogyne hapla.In present study, soil pH showed positive correlation with the population of Tylenchorhynchus spp. However, soil pH was found to be negatively correlated with the population buildup of Pratylenchus spp., Meloidogyne spp., Helicotylenchus spp. And Ditylenchus spp. Soil moisture showed its positive correlation with Helicotylenchus spp., Aphelenchus spp., Criconemoides spp., Pratylenchus spp., Tylenchorhynchus spp. And Ditylenchus spp. While population buildup of Meloidogyne spp., Aphelenchus spp., Tylenchorhynchus spp., Pratylenchus spp. and Ditylenchus spp. were found to be negatively correlated with soil temperature. On the basis of survey, it can be inferred that occurrence of root knot nematode is a serious threat to kiwi growing areas in Uttarakhand. Instant attention of the researchers and kiwi growing community is required to take appropriate decision to limit their further spread. Kiwi farmers need to be aware about the threat so that timely preventive management strategies could be taken so as to increase the quality and yield of kiwi crop.
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    ThesisItemOpen Access
    Studies on the effect of fungicides, biocontrol agents and organic amendments against wilt of lentil incited by Fusarium oxysporum f.sp. lentis
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Kavya, H.G.; Tewari, A.K.
    Lentil wilt caused by Fusarium oxysporum f.sp. lentis is a major problem in all lentil growing areas of the world as well as in India. In India lentil wilt is one of the major causes behind reduced production and productivity of lentil in recent years. Lentil wilt resulted in yield loss of 50-78 per cent from moderately infected fields and 100 per cent loss from severely infected fields. In the present investigation, efforts were made to validate different management strategies against F. oxysporum f.sp. lentis. Fungicides, Peak Max and biocontrol agents were evaluated under in-vitro conditions as well as under greenhouse conditions. However, effects of different organic amendments were studied under greenhouse conditions. Bioagents and Peak Max were also studied to know their role in induction of resistance through polyphenol oxidase activity and phenylalanine ammonia lyase. In-vitro among fungicides Azoxystrobin 18.2% +Tebuconazole 18.3% SC and Carbendazim 50% WP each at 100 ppm completely inhibited (100%) radial growth of F. oxysporum f.sp. lentis. Under greenhouse conditions seed treatment + drenching with Azoxystrobin 18.2% +Tebuconazole 18.3% SC showed significantly maximum per cent disease reduction (69.35%) followed by Carbendazim 50% WP (61.49%) each at 0.1 per cent at 45 days after sowing over inoculated control. In dual culture studies among biocontrol agents Trichoderma isolate PBTR-1 was found significantly most effective in mycelial parasitization (99.3%) of F. oxysporum f. sp. lentis followed by Th- 14 (54.42%). Among bacterial bioagents Bacillus isolate PBBSR-1 showed highest width of inhibition zone (14.36 mm) followed by PBBSR-2 (11.29 mm). In greenhouse conditions significantly maximum per cent disease reduction (30.75%) was observed in seed treatment + soil application + drenching with Trichoderma isolate PBTR-1 followed by Th-14 (11.32%) over inoculated control at 45 days after sowing. Among the tested organic amendments Neem cake showed significantly maximum per cent disease reduction (70.16%) followed by Kunapajala-3 (30.35%) at 45 days after sowing over inoculated control under greenhouse conditions. The induction of defense related enzyme polyphenol oxidase was found significantly maximum (4.54 ΔO.D./ min/g of fresh tissue) in Trichoderma isolate PBTR-1 at 72 hrs while, phenylalanine ammonia lyase activity (1.99 O.D./ min/g of fresh tissue) maximum at 48 hrs followed by Th-14 in polyphenol oxidase activity (4.25 ΔO.D./min/g of fresh tissue) and phenylalanine ammonia lyase activity (1.96 O.D./min/g of fresh tissue) after drenching at 8 days after germination. Among various treatments soil application of Neem cake (50 g/kg of soil) was found best with maximum per cent disease reduction (70.16%) followed by Azoxystrobin 18.2% +Tebuconazole 18.3% SC (69.35%), Carbendazim 50% WP (61.49%) each at 0.1 per cent, Trichoderma isolate PBTR-1 (30.75%) at 1 per cent and Kunapajala-3 (30.35%) at 10 per cent at 45 days after sowing. These treatments could be further studies in different combination under field conditions for the eco-friendly cost-effective management of lentil wilt. The integration of Trichoderma isolate PBTR-1, Neem cake and Kunapajala-3 could be tested under field conditions for the management of lentil wilt under organic farming.