ThesisItem Open AccessManagement of Lentil Wilt Caused by Fusarium oxysporum f. sp. lentis(COLLEGE OF AGRICULTURE, UMMEDGANJ, KOTA, 2020-12-09) MEENA, MEENU KUMARI; Meena, C. B.Lentil is one of the major legume crops and play very important role in supply of protein to under nourished vegetarian population of the country. Lentil wilt caused by Fuasrium oxysporum f. sp. lentis is one of the main limiting factors for successful cultivation of lentil in India, causing significant economic losses. Lentil wilt symptoms recorded from infected plants was gradually drying of plants from the seedling stage up to flowering and late pod filling stage. Symptoms as leaves turn yellow and curling of leaves begins from the lower end and extends up wards. Then crown droops and this is followed by the death of the plant. The root system was developed poorly and discolored brown. The fungus was isolated and purified from wilted lentil plant collected from field of Agriculture Research Station Ummedganj, Kota and found pathogenic to cause lentil will. Further, identified as Fusarium oxysporum f,sp lentis by ITCC, Division of Plant Pathology IARI, New Delhi. Mycelium growth and sporulation were maximum on oat meal agar (Hi-media) medium was statistically at par with potato dextrose agar (Himedia), epidemiological requirement of pathogen was 30 ℃ temperature & pH level 6.0 under lab experiment. Result revealed that none of entries are immune and highly resistant (HR), 11 entries were resistant (R), 5 entries are moderately resistant (MR), 4 entries as susceptible (S), While, no one among these entries were recorded as highly susceptible (HS). Four species of Trichoderma were tested against Fusarium oxysporum f. sp. lentis dual culture technique inoculated at different time of interval, T. viride found most effective for growth inhibition of pathogen in all the bio-agents tested in dual culture with reference the time interval. Result also indicated that, the pathogen inoculated 96 hrs. before bioagent inoculation gave good antagonistic reaction in dual culture technique. Out of seven systemic and non-systemic fungicides, most effective was found Carbendazim 50% WP, Propiconazole 25% EC inhibited completely the mycelial growth of Fusarium oxysporum f. sp. lentis at all concentrations tested, it was statistically at par with hexaconazole 5% EC at 125 & 200 ppm respectively. Under pot experiment standardization of inoculum level maximum lentil wilt incidence was observed in pots where mass culture added @ 10 g/kg soil of pot (89.09%) whereas, minimum lentil wilt incidence (47.42%) was recorded in pots where mass culture added @ 2 g/kg soil of pot. Concluded that inoculum density is bound to influence the disease incidence. Bioagents applied through seed treatment @ 0.6% spore suspension / kg seeds (1x108 spore /ml) for manage lentil wilt. Trichoderma viride showed more protection against lentil wilt and recorded more yield followed by Trichoderma harzianum. Trichoderma spp. had synergistic impact on plant vigour and grain yield. Carbendazim 50% WP applied through seed treatment @ 0.2% / kg seeds gave maximum protection against lentil wilt, it was followed by hexaconazole 5% EC in pot experiment. ThesisItem Open AccessDetection and Management of Early Blight of Potato Caused by Alternaria alternata(COLLEGE OF AGRICULTURE, UMMEDGANJ, KOTA, 2020-12-09) MEENA, PRIYANKA KUMARI; Yadav, D. L.Potato is the King of vegetables and third most important food commodity in terms of human consumption after rice and wheat. Potato has immense potential for food and nutritional security of the world. India is the second largest producer of potato in the world. Diseases are major constraint resulting in loss in tuber yield of potato.Early blight is one of most important foliar diseases of potato and reported 24 to 54% disease severity in South Eastern Rajasthan. Consequently, the present studies have been undertaken to overcome crop loss by finding suitable disease management. The present investigation on “Detection and Management of Early blight of potato caused by Alternaria alternata.” was carried out at Agricultural Research Station, Agriculture University, Kota during Rabi 2019-20 under laboratory as well as field condition. First symptom of the disease was seen on older leaves as small dark brown, frequently round necrotic spots, the spots enlarged with characteristics in the centre to produce a target board effect and the colour of the spots altered from brown to dark brown. The disease symptoms perceptibly seen on all plant parts viz., leaf, stem and petioles. The contiguous spots eventually coalesced to form large irregular spots primary to drying and defoliation. The diseased plants formed less tuber and size of tuber as compared to healthy plant. Pathogen was isolated by single spore isolation technique from infected potato leaves and pure culture of the fungus was obtained on potato dextrose agar medium after eight days of inoculation which showed brownish colour. The studies on the morphological and colony characters of the isolated pathogen showed its close identify with Alternaria alternata. The mycelium was greyish brown to black producing conidiophores moreover singly or in small groups which were straight or flexuous brown to olivaceous brown. The conidia were solitary straight or muriform or ellipsoidal narrowing to beak, pale or olivaceous brown. For further, identification of pathogen was sent to Indian Type Culture Collection (ITCC), Division of Plant Pathology, IARI, New Delhi-110012. They identified culture as Alternaria alternata with code number 295012. Significantly maximum inhibition of mycelial growth was obtained with Trichoderma viride (57.08%) followed by T. azospirillum (50.00%), T. harzianum (43.26%) and T. virens (37.08%) of the pathogen after 48hours of incubationby dual culture technique. Among the media tested the potato leaf agar and was significantly superior and most effective medium for sporulation as well as potato leaf broth medium for dry mycelial weight followed by PDA. However potato leaf agar was also superior for sporulation of A. alternata. Whereas, the potato stem agar, V-8 juice agar, pea agar, oat meal agar and czapek’s agar medium were least effective in mycelial growth.Screening of twenty eight genotypes/varieties of potatofor resistance to early blightdisease revealed six genotypes viz., CP-3021, 3153, Atlantic, Chip-3, Jx-161 and MS/78-62 as resistant reaction. While thirteen genotypes i.e., NJ-1501, MP-97, NJ-44, NJ-34, MP-97-1606, PS/RI-135, JI-93-77, MS/94-118, JN-1177, Kufri Sindhuri, Kufri Pukhraj, Kufri Khayati and Kufri Pushkar moderately resistant. However, six genotypes viz., NJ-85, NJ-1530, J-92-164, MS/92-2105, J/93-4 and Kufri Bahar susceptible, while three genotypes i.e., MP/94-322, NJ-1 and MS/85- 1663 as highly susceptible. Fungicides viz., Propiconazole 25% EC and Hexaconazole 5% EC @ 10, 20 and 50 ppm concentrations and Mancozeb 75% WP @ 1000 and 1500 ppm and Difenconazole 25% EC @ 50 ppm significantly were recorded 100 per cent inhibition as compared to rest of the fungicides.Next best treatments in order of merit were Difenconazole 25% EC @ 10 and 20 ppm, Mancozeb 75% WP @ 500 ppm and Azoxystrobin 23% SC @ 10, 50 and 100 ppm, Picoxystrobin 22.52% SC andPyraclostrobin 20% WG @ 10, 50 and 100 ppm concentrations against the Alternaria spp. The studies on foliar spray of fungicides against early blight under field condition revealed that the highest per cent reduction over control i.e. 72.3% was recorded in Dinfenconazole 5% EC @ 250 ml/ha followed by spraying of Propiconazole 25% EC @ 500 ml/ha (71.3%) and Azoxystrobin 23% SC @ 500 ml/ha 70.2% after first and second spray. Next best treatments in order of merit were Picoxystrobin 22.52% SC @ 400 ml/ha i.e. 68.2% which was on par with Pyraclostrobin 20% WG @ 500 ml/ha 66.3% disease control after 14 days of each spray, while Hexaconazole 5% EC @ 500 ml/ha gave 63.6% and Mancozeb 75% WP @ 1500 g/ha showed 57.4% disease control 14 days after first and second spray. Significantly maximum percent dry matter was recorded by foliar spray of Azoxystrobin 23% SC @ 500 ml/ha (25.00%). Next best treatments in order of merit were Pyraclostrobin 20% WG (24.03%), Picoxystrobin 22.52% SC (23.87%) and Hexaconazole 5% EC (23.07%), Mancozeb 75% WP (22.23%) and Difenconazole 25% EC (22.00%). Whereas, 21.20% was recorded by Propiconazole 25% EC and 20.13% in control. The highest (269) total tuber no. per plot was observed in Azoxystrobin 23% EC @ 500 ml/ha followed by Picoxystrobin 22.52% SC (260), Pyraclostrobin 20% WG (258), Difenconazole 25% EC (257) and Propiconazole 25% EC (247) which were at par with each other. However, Mancozeb 75% WP (238), while minimum was recorded in untreated checks i.e. (198) tubers.The studies on the effect of foliar sprays of various fungicides on tuber yield revealed that Azoxystrobin 23% SC @ 500 ml /ha gave highest 16.17kg total tuber yield per plot followed by Picoxystrobin 22.52% SC (15.8 kg), Pyraclostrobin 20% WG (15.4 kg), Difenconazole 5% EC (14.93 kg) and Propiconazole 25% EC (13.83 kg), Mancozeb 75% WP (14.63 kg) and least tuber yield in Hexaconazole 5% EC (12.93 kg) as compared to control (10.57 kg). The highest cost benefit ratio was obtained in strobolin group fungicides followed by Mancozeb 75% WP and trizole group fungicides. Cost benefit ratio was least in control. ThesisItem Open Access“Investigations on Alternaria alternata Causing Blight Disease in Tomato (Solanum lycopersicum L.)”(COLLEGE OF AGRICULTURE, UMMEDGANJ, KOTA, 2020-09-26) Jewaliya, Balram; Gautam, ChiragAmong the several diseases of tomato, leaf blight disease caused by Alternaria alternata is one of the most destructive disease which causes heavy losses in fruit yield of tomato. Per cent disease index (PDI) varied from 34.34 to 49.98 per cent in four surveyed districts viz., Kota, Bundi, Baran and Jhalawar of Hadoti region of Rajasthan. Maximum PDI was recorded in Charchoma village of Kota district (49.98%) while minimum was recorded in Azampur village of Jhalawar district (34.34%). Among the districts, disease severity was found to be maximum in Kota (44.06%), while least in Jhalawar (38.08%). The Pathogen was isolated from infected tomato plants showing typical leaf blight symptoms, purified and its pathogenicity was proved. The pathogen produced dark brown to black colony with septate mycelium and acropetal chain of ellipsoidal brown or muriform conidia, thus identified as Alternaria alternata which was further got confirmed by ITCC, Division of Plant Pathology, IARI, New Delhi (Ref. ID 11, 291.20). Cultural and morphological variability regarding colony diameter, colony colour, growth pattern, margin colour, topography, thickness of mycelium mat and sporulation were observed among seven isolates of Alternaria spp., collected during survey. AltKo1 isolate from Charchoma village of Kota showed maximum growth and sporulation on Potato dextrose agar (PDA) medium. Among seven solid culture media, PDA medium found better for mycelium growth and sporulation of Alternaria alternata. Out of seven liquid media, Oat meal broth gave maximum dry mycelium weight followed by Potato dextrose broth. Among seven fungicides tested, Hexaconazole @ 5 EC recorded maximum inhibition of mycelial growth (with mean 97.96%) at all concentrations under in vitro condition. Out of four bio-agents tested, Trichoderma harzianum found most effective followed by Trichoderma viride under in vitro condition. Out of six botanical extracts tested in vitro, Azadirachta indica (leaf extract) gave best result with 96.11 per cent inhibition of mycelial growth followed by seed extract of Azadirachta indica (94.11%). ThesisItem Open AccessManagement of Collar Rot caused by Sclerotium rolfsii (Sacc.) in Chickpea (Cicer arietinum L.)(COLLEGE OF AGRICULTURE, UMMEDGANJ, KOTA, 2020-12-09) SINGH, KARAN; Meena, C. B.Chickpea (Cicer arietinum L.) is the largest produced very important legume crop in South Asia and the third largest produced legume crop globally. Collar rot of chickpea caused by Sclerotium rolfsii is one of the most important fungal disease, prevalent in all chickpea growing areas of India including Rajasthan. The symptoms of collar rot in chickpea include initial yellowing of affected plant leaves and show signs of rotting at collar region. Disease incidence of collar rot in chickpea was in the range of 6.69% - 19.82% in the chickpea growing areas of nearby places of ARS, Ummedganj, Kota of Rajasthan. Maximum incidence was recorded in field of Agriculture Research Station, Ummedganj & Mechanized Agriculture Farm, Ummedganj (19.82%) and minimum Char-chouma 6.69%. The pathogen isolated from infected plant sample and purified. In pathogenicity test, the fungi S. rolfsii was found to be highly pathogenic as they reduced the germination and cause very high seedling mortality. The physiological requirement of pathogen for maximum growth and numbers of sclerotia production of S. rolfsii was observed on Oat meal agar medium (90.00 mm) and (691.00 per plate). While, on 25 ℃ temperature (90.00 mm) & (538.50 per plate) and pH level 7.0 (89.00) & (570.00 per plate) respectively. Four Trichoderma spp. were evaluated by dual culture technique for their antagonistic effect against S. rolfsii under in-vitro conditions, T. viride showed maximum growth inhibition 54.67% four days after incubation. Among eight botanical extracts tested through poisoned food technique against pathogen under lab condition 96 hrs. after of inoculation of pathogen neem seed kernel extracts recorded maximum mycelial growth inhibition of 59.44 percent at 15% concentration respectively. The efficacy of ten chemical fungicides were evaluated in-vitro at three concentrations viz., 100, 125 and 200 ppm concentration against S. rolfsii, by poisoned food technique. Among these, carboxin 37.5% + thiram 37.5% WS (vitavax) was completely inhibited mycelial growth of test fungus at all concentrations tested. Ten genotypes/varieties viz., RKG-13-515, GNG-1958, RKG-18-1, JG- 14, RVG-201, GNG-1469, GNG-2144, JG-16, CSJ-515(c) and RKG-13-515 (1) were sown in pots, out of the 10 entries screened with soil inoculated in cemented pots, no one varieties show resistance against collar rot disease. Two most effective in-vitro evaluate Trichoderma spp. used against collar rot disease of chickpea in pot experiment with soil inoculation of pathogen, Maximum percent reduction in PESR (90.91%) and PESM (43.75%) were recorded in Trichoderma viride applied through integration of soil application & seed treatment. Among in-vitro evaluate three most effective botanical extracts was tested against collar rot disease of chickpea in pot experiment with soil inoculation of pathogen. Maximum percent reduction in PESR (63.64%) was recorded in neem seed kernel extract (NSKE) applied through seed treatment. Maximum percent reduction in PESM (37.50%) was recorded in NSKE applied through integration of seed treatment & post emergence seedling drenching at 7 days after germination. Three chemical fungicides found most effective in In-vitro against collar rot disease of chickpea pathogen was further evaluated in pot experiment with soil inoculation of pathogen. Maximum percent reduction in PSER (100.00%) was recorded in vitavax power applied through seed treatment. Maximum percent reduction in PESM (62.50%) was recorded in hexaconazole applied through integration of seed treatment & post emergence seedling drenching at 7 days after germination. ThesisItem Open AccessEPIDEMIOLOGY AND MANAGEMENT OF EARLY BLIGHT IN POTATO CAUSED BY Alternaria alternata L.(COLLEGE OF AGRICULTURE, UMMEDGANJ, KOTA, 2021-09-09) HADA, RITIKA; Yadav, D. L.Early blight caused by Alternaria alternata is a destructive disease which causes heavy losses in tuber yield of potato in South Eastern Rajasthan. Surveys were conducted to determine the incidence of early blight in Kota, Baran and Bundi districts of South-Eastern Rajasthan and revealed that disease incidence was ranged from 12.5 to 23.8 per cent. The maximum disease incidence was recorded in Anta village of Baran district 23.8 per cent while, minimum was recorded in Suvana and Keshoraipatan village of Kota and Bundi district 12.5 per cent. A field experiment was conducted to assess the progress of early blight disease intensity as influenced by three planting dates and four varities. The four varities i.e. Kufri Bahar, Kufri Sindhuri, Kufri Pukhraj and Kufri Pushkar were planted at every fifteen days interval i.e. 23rd Oct, 6th Nov and 20th, Nov, 2019, respectively. Out of three planting dates, minimum disease intensity was recorded with 2nd date of planting (6th Nov, 2019) in K. Sindhuri (8.5 %) followed by K. Pushkar (11.5 %), K. Bahar (21.5 %) and K. Pukhraj (30.0 %) as compared to 1st (23rd Oct, 2019) and 3rd (20th Nov, 2019) date of planting. Minimum per cent disease intensity of early blight was recorded in variety K. Sindhuri (12.5 %) and K. Pushkar (13.5 %). Epidemiological studies revealed that maximum and minimum temperature was highly significant with negative correlation. The yield data indicated that planting on 6th November i.e. 2nd date of planting produced maximum total number of tubers per plot, marketable yield and total tuber yield (t/ha) and among the varieties maximum total tuber yield and marketable yield were obtained i.e. 16.7, 18.2, 14.9, 17.3 and 14.3, 16.9, 13.7, 15.6 t/ha in K. Bahar, K. Sindhuri, K. Pukhraj and K. Pushkar, respectively. Hence, first week of November i.e. 2nd date of planting could be considered as an effective to minimize early blight disease of potato in Kota zone of Rajasthan. Fungicide, Azoxystrobin 23 % SC @ 2 ml/lit per 20 kg of tuber seed treatment combined with two foliar spray of Azoxystrobin 23 % SC @ 1 ml/lit was recorded maximum per cent disease control (76.49 %), minimum per cent intensity (6.62 %) with better dry matter (22.6 %), total number of tubers (548.00 per plot), tuber yield (25.67 t/ha), marketable yield (21.93 t/ha) with highest net gain of Rs. 67,620. Among bio-agents i.e. Trichoderma viride @ 8 g/lit per 20 kg of tuber treatment combined with two foliar spray of T. viride @ 5 g/lit of water was showed maximum per cent disease control (65.48 %), minimum per cent intensity (9.27 %) with superior dry matter (22.3 %), total number of tubers (485.33 per plot), total yield (22.47 t/ha) and marketable yield (19.10 t/ha) with highest net gain of Rs. 47,712. Hence, the chemical fungicide Azoxystrobin was found more effective in managing the disease but due to continuous and irrational use of these chemicals, pathogens have developed resistance against the fungicides and also aid in environmental pollution and toxicity in the produce whereas, bio-agents are naturally occurring living organisms, which are found in rhizosphere, phylloplane, etc. These bio-agents help in not only managing the diseases but also increasing the crop yield. Hence, application of T. viride @ 8 g/lit per 20 kg of tuber treatment combined with two foliar spray of T. viride @ 5 g/lit of water could be used in the management of early blight in potato. ThesisItem Open AccessEPIDEMIOLOGY AND MANAGEMENT OF STEM NECROSIS DISEASE OF POTATO IN SOUTH-EASTERN RAJASTHAN(COLLEGE OF AGRICULTURE, UMMEDGANJ, KOTA, 2021-12-06) MEENA, MAHESH KUMAR; Yadav, D. L.Potato stem necrosis disease is serious problem in the early planted potato crop and it caused by a tospovirus which transmitted through Thrips palmi. Initially brown necrotic spots were appeared on young stem, veinal necrosis on abaxial side of leaf, blacking and collapse the entire stem with necrosis in concentric patterns with dark necrotic lesions covered the stem. Maximum disease incidence was recorded in Suvana village (22.5%) of Kota district and 21.5 per cent in Anta village of Baran district. Whereas, minimum PDI was observed in Arjunpura (8.5%) and followed by Chandresal village of Kota (9.5%). Out of three dates of planting, maximum disease incidence was recorded in 1st and 2nd date of planting i.e. 10th October, 2019 and 20th October, 2019. While, minimum was observed in 3rd date of planting (30th October, 2019). 63.16 % yield reduction was recorded at 5 grade of stem necrosis disease in field condition during experiment. The correlation between the disease incidence and weather factors revealed that maximum and minimum temperature was highly significant with positive correlation in all four varieties i.e. K. Bahar, K. Sindhuri, K. Pukhraj and K. Pushkar in first date of planting (10th Oct 2019). Similarly, the correlation between the thrips population and weather factors revealed that maximum and minimum temperature was highly significant with positive correlation in all four varieties in first date of planting. The correlation between the stem necrosis and thrips population was observed highly significant with positive correlation. Highest AUDPC value was found in 1st date of planting in all four varieties. However minimum AUDPC was recorded in 3rd date of planting in all four varieties i.e. K. Bahar (180.25), K. Sindhuri (162.75), K. Pukhraj (217.00) and K. Pushkar (197.75), respectively. Maximum total number of tubers, marketable yield and total tuber yield (q/ha) was observed in 3rd date of planting. Foliar spray of fipronil 5% SC @ 1.5 ml/lit was recorded maximum per cent disease control (85.97%), minimum per cent intensity (4.66%), total number of tubers (498.67/plot), tuber yield (210.8 q/ha), marketable yield (184.9 q/ha) along with net gain (Rs/ha) 55398. Next best treatment in order imidacloprid 17.8% SL (0.3 ml/lit) combined with mancozeb 75 WP @ (2 gm/lit) of water. However, maximum disease intensity (32.22%) was recorded in control. ThesisItem Open AccessISOLATION AND CHARACTERIZATION OF ANTAGONISTIC BACTERIA FROM THE RHIZOSPHERE OF CHICKPEA (Cicer arietinum L.)(COLLEGE OF AGRICULTURE, UMMEDGANJ, KOTA, 2021-08-26) MATHUR, ADITI; Gautam, ChiragChickpea (Cicer arietinum L.) is the world’s third most important pulse crop after dry beans (Phaseolus vulgaris) and dry peas (Pisum sativum L.). India is the world’s leading producer of chickpea. Chickpea, a major crop of Hadoti region is suffered with many soil borne plant pathogens including Fusarium oxysporum f.sp. ciceri and Macrophomina phaseolina which causes wilt and dry root rot respectively. Biological control provides a low-cost, environmentally acceptable alternative to the use of expensive and damaging pesticides by reducing the activity of plant diseases. Rhizobacteria are among the one of the plant growth promoters and antagonistic organisms against soil borne pathogens. They dominate the rhizosphere and has a number of properties that have made them a popular biocontrol agent. The mechanisms by which these bacteria affect the plant growth include rhizosphere colonization, antibiosis, phosphate solubilization, iron chelation by siderophore production and induced systemic resistance. In present investigation, samples of rhizospheric soils and roots were collected from chickpea growing fields at Agricultural Research Station and College of Agriculture, Ummedganj, Kota. A total of 10 isolates were obtained from different soil samples collected before and after flowering from different investigation sites. Isolation of rhizobacteria was done on nutrient agar. Rhizobacterial isolates were designated as PR 1 to PR 10 and distinguished on the basis of morphological and biochemical characterization. On nutrient agar medium, in visible light, isolates PR 2 and PR 3 showed yellow pigment, PR 5 showed light yellow pigment and the rest of the isolates showed white pigment after 3 days of incubation. PR 3 and PR 4 showed fluorescence under U.V. light at 365nm while others were non fluorescent.The results of biochemical tests performed revealed that all the isolates showed similar results with regard to gram staining (negative), catalase test (positive), H2S test (positive) and KOH test (positive). PR 1, PR 2, PR 5, PR 7, PR 8, PR 9 and PR 10 showed positive results in starch hydrolysis test. Out of 10 isolates, 7 isolates showed positive results for casein hydrolysis, 6 isolates showed positive results for indole production and only 2 isolates PR 6 and PR 7 showed positive results for urease test. Antagonistic ability of rhizobacterial isolates was evaluated under laboratory conditions through dual culture method against F. oxysporum f. sp. ciceri and M. phaseolina. Mycelial growth inhibition of Fusarium oxysporum f. sp. ciceri was found maximum against PR 3 (55.22%) followed by PR 2 (16.33%). The inhibition of M. phaseolina by the rhizobacteria was found lower than that from F. oxysporum, but maximum growth inhibition was found when PR 3 (16.44%) was used as an antagonist. PR 3 was further characterized for the purpose of identification. PR 3 showed round colony with an entire/regular margin and a slightly raised elevation. The colony was smooth and transparent, with yellow pigmentation that fluoresces under U.V. light and showed negative gram staining reaction. The isolate was found to be a highly motile on SIM medium, microscopic observations revealed short rod-shaped bacteriumoccurring in single cell arrangement. Biochemical tests revealed that rhizobacterial isolate PR 3 showing antagonism against F. oxysporum f. sp. ciceri, was positive for catalase and oxidase tests, and negative for starch hydrolysis, and may thus be identified as a strain of Pseudomonas fluorescens.