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ThesisItem Open Access Biochemical changes in fenugreek due to powdery mildew (Erysiphe polygoni DC.) and its management(2022) B.R, Rachanashree; Kumawat,G.L.Fenugreek (Trigonella foenum-graecum L.) is one of the important and oldest spice and medicinal crops and is cultivated throughout India. It is attacked by many diseases, however, powdery mildew incited by Erysiphe polygoni DC. is a major constraint in cultivation of fenugreek. Powdery mildew disease appeared during the end of January and persisted till the maturity of the crop. Symptoms were observed as white floury patches on leaves, tendrils, stem and pods whereas cleistothecia appeared late in the season seen as black specks immersed in mycelial mat. Microscopic observation revealed that conidia were barrel in shape and formed singly and in chains. Conidiophores were septate that were straight to sub-straight with 4 to 5 cells. Thirty six genotypes and varieties were screened under natural condition to find out the source of resistance against the disease. It was found that HM 444 and UM 411 showed resistant reaction with percent disease intensity (PDI) of 9.66 and 10.27 respectively. The remaining nine were rated as moderately resistant, thirteen as moderately susceptible and twelve as susceptible.Biochemical studies on thirty six genotypes and varieties were undertaken twice, once before the disease occurrence and then after the disease occurrence. It was found that total phenol, peroxidase (PO) and polyphenol oxidase (PPO) content in plants increased in all the genotypes after the disease appearance and the amount of these components were higher in resistant ones and comparatively lower in susceptible ones. Chlorophyll content of all the lines decreased after the disease appearance and was greater in resistant lines than susceptible lines. Correlation between biochemical components and percent disease intensity was worked out. Phenol showed negative significant correlation (- 0.958) (-0.864) in both healthy and infected leaves with PDI, the enzyme peroxidase showed negative significant correlation (-0.929) (-0.847) in both healthy and infected leaves with PDI, the enzyme PPO showed negative significant correlation (-0.892) (-0.837) in both healthy and infected leaves with PDI and chlorophyll also showed negative significant correlation (-0.758) (-0.892) with PDI. Six treatments were evaluated along with one untreated control in three replications. Among them, two sprays of panchgavya 5% recorded minimum percent disease intensity of 30.66 with yield 13.47 q/ha. Field evaluation of six systemic acquired resistance elicitors with one unsprayed control in three replications were undertaken. The crop was sprayed at 45 days after sowing and it was found that salicylic acid 200 ppm resulted in minimum percent disease intensity of 21.18 and yield of 16.07 q/ha. Six fungicides with one treatment of water spray and untreated control in three replications were carried out twice where hexaconazole 5% SC at 0.1% recorded minimum percent disease intensity of 11.63 and with higher yield of 20.65 q/ha. ICBR for fungicides were calculated and hexaconazole showed maximum ratio of 1: 37.91ThesisItem Open Access Biochemical Changes in Pea Due to Powdery Mildew Incited by Erysiphe polygoni DC and its Management(2022) MEENA, DINESH KUMAR; Singh, JitendraPea (Pisum sativum L.) is an important cool season crop, belongs to the Leguminosae family. Pulses are providing quality food to teeming million and restoring soil fertility through nitrogen fixation. Pea crop is damaged by many fungal, viral and bacterial diseases. Powdery mildew of pea incited by Erysiphe polygoni emerged as a major disease in Rajasthan. Generally, this disease appeared in the first week of March and reaches at peak in April. Powdery mildew of pea is detected by presence of white floury patches appearing on upper and lower sides of the leaves as well as pods, stem, tendril etc. in extreme condition it causes significant losses in quantity and quality of the seed. In vitro studies showed that the highest conidial germination was reported at 250C temperature and 80 per cent relative humidity. Among biochemical basis of resistance in pea, peroxidase and phenol content are minimum in healthy plants compared to infected plants. Reducing sugar is maximum in healthy plants as compared to infected plants. Among tested six natural products used as two foliar applications; Neem Seed Kernel Extract (NSKE) was found most effective with 62.38 per cent disease control. Followed by Panchgavya with 57.50 per cent disease control. Among tested five SAR activators single spray of salicylic acid @250ppm before disease appearance recorded minimum 25.71 per cent disease intensity by decreasing 55.07 per cent disease intensity over control. Out of six fungicides tested for their efficacy for the control of Erysiphe polygoni on pea. Two foliar spray of Hexaconazole @0.1% first at before disease appearance and second at after disease appearance were found minimum 13.85 per cent disease intensity by decreasing 76.55 per cent disease intensity over control followed by Propiconazole was second best recorded with 16.68 per cent disease intensity by decreasing 71.76 per cent disease intensity over control.ThesisItem Open Access Management of Alternaria leaf spot of coriander incited by Alternaria alternat(2022) KANSOTIA, KAVITA; Meena, A.K.Coriander (Coriandrum sativum L.) is an important seed spice crop of India specially growing in Rajasthan. The crop suffers from several disease among those leaf spot is emerging as a major problem in coriander cultivation. Leaf spot infected leaves of coriander were collected from farmer’s field. Pathogen was isolated, purified and identified as Alternaria alternata and its pathogenicity was proved. Four bio-agents were evaluated against Alternaria alternata by dual culture technique. Among all the tested bio-agents Trichoderma harzianum was found best which inhibit maximum mycelial growth (74.44%) of fungus. When bio-agents were used as seed treatment and soil application under field conditions, Trichoderma harzianum was found most effective and resulted in significant reduction in disease intensity (38.30%) as compared to untreated control. The leave extract of five plant species were evaluated at two concentrations (5% and 10%) against Alternaria alternata by Poisoned Food Technique. The leave extract of neem (88.88% at 10% and 83.33% at 5%) followed by garlic were found most promising in inhibiting mycelial growth at both concentrations. When plant leave extracts tested as foliar application under field conditions, neem was found most effective with maximum disease control (50.94 at 10%) followed by garlic leave extract. Biochemical studies on coriander leaf spot disease induced by A. alternata was carried out. Significant increase in phenol and peroxidase (PO) was found in infected plants as compared to healthy plants. A reduction in sugar content was also observed with the increase in disease severity. * A Post Graduate Student, Department of Plant Pathology, S.K.N. College of Agriculture, JoThesisItem Open Access Studies on Management of Dry Root Rot of Mungbean [Vigna radiata (L.) Wilczek] Caused by Macrophomina phaseolina (Tassi) Goid.(2022) Anupriya; Chawla, NitinMungbean (Vigna radiata (L.) Wilczek) commonly known as green gram or “Mung” one of the most popular pulse crop in India. Root rot caused by Macrophomina phaseolina, is a widespread disease of mungbean in India including in the state of Rajasthan. The pathogen is a polyphagous necrotroph in nature that can up to 15 years in the soil. The management of M. phaseolina is required. The incidence of pathogen varies from 17 to 90 per cent incidence in India with 25 to 48 per cent yield losses in mungbean. A roving survey was conducted during the Kharif season of 2020 in major mungbean growing districts (Bikaner, Hanumangarh, Sri Ganganagar, Churu, Nagaur and Jaipur) to know the disease incidence in different areas of Rajasthan. The disease incidence varies from 17.12% to 28.49% with an average disease incidence of 22.67 per cent. The higher disease incidence (28.49%) was recorded the districts in Bikaner while least in Jaipur (17.12%) district. The pathogen was isolated, purified and proved pathogenic of mungbean through soil inoculation technique. Among 52 genotypes/varieties using, two genotypes Pusa 0871 and SML 1839 were found resistant and (RMG 1139) was moderately resistant. Protein contents were low whereas phenolic and proline contents increased in roots due to disease. The chlorophyll contents in leaves of infected plants were low in comparison to leaves of healthy plant. In variability studies of 12 isolates, Mp-PGE isolate, collected from Jhadla village of Phagi tehsil in Jaipur district, was comparative in fast mycelial growth, whereas Mp-LKS isolate from Peepera village from Lunkaransar tehsil of Bikaner showed slower mycelial growth. These isolates were shown significant differences in terms of radial growth, colony colour, colony diameter, colony texture, mycelial dry weight, sclerotia shape and size and sclerotia number.The, garlic clove extract, T. harzianum and in fungicides, trifloxystrobin 25% + tebuconazole 50% WG (50, 100, 200, 500ppm) significantly inhibited mycelia growth of the pathogen under in vitro studies among other treatment. When applied seed treatment were also tested in pot conditions through and these were found effective in controlling disease. In the field study, maximum disease reduction and higher seed yield were recorded with trifloxystrobin 25%+ tebuconazole 50% WG @ 0.10% while the seed treatment with propineb 70% WP @0.20% was found least effective up to 40 DAS. Under pot conditions, seed treatment with T. harzianum @ 10g/kg seed + soil application of mustard cake @ 0.5t/ha was found most effective. In the field study, maximum per cent disease reduction and higher seed yield were recorded with T. harzianum @ 10 g/kg seed + soil application of mustard cake @ 0.5t/haThesisItem Open Access Interaction of Fusarium solani and Meloidogyne javanica in Causing Root Rot of Fennel and its Managemen(2022) KUMAWAT, KIRAN; Goyal, S.K.Fennel is one of the important seed spice crops grown in India Fusarium solani and Meloidogyne javanica are widely distributed pathogens in India which cause root rot and root knot complex in fennel and responsible for severe economic losses. Considering the economic importance of these, the present investigation was carried out to know the interaction of Fusarium solani and Meloidogyne javanica in causing root rot of fennel and its management. Fennel plants depicting root rot symptoms were collected from farmer’s field. The fungus, Fusarium solni was isolated from infected fennel plants, purified by single spore technique and proved pathogenic. An experiment was conducted on interactive effect of Fusarium solani and Meloidogyne javanica on root rot incidence in fennel. Minimum nematode reproduction and maximum plant growth parameters were recorded by inoculating fungus at the time of sowing and nematode after one week. While, maximum disease incidence was recorded by inoculating nematode at the time of sowing and fungus one week after. Among screened 30 varieties/germplasm of fennel, four varieties (RF-101, RF-145, RF-157 and RF-143) showed resistant reaction, 21 showed moderately resistant reaction and five showed susceptible reaction against the pathogens. Among all varieties/germplasm, highest root rot incidence was recorded in RF-125 and UF-33. However, minimum root rot incidence was recorded in RF-101 and RF 205. An experiment was conducted on management of the root rot and root knot disease complex through bio-agents (@ 2.5kg/ha as soil application) and botanicals (@ 10% concentration as seed soaking). Among all the treatments, combination of Trichoderma harzianum and garlic showed best results followed by Trichoderma harzianum + parthenium for increase plant growth parameters and reduce percent root rot incidence as well as nematode reproduction as compared to untreated control. Biochemical studies were also carried out to find the peroxidase, polyphenol oxidase, phenylalanine ammonia lyase and phenol level. Highest peroxidase, polyphenol oxidase, phenylalanine ammonia lyase and phenol activities was observed in Trichoderma harzianum and garlic followed Trichoderma harzianum + parthenium and parthenium treated fennel roots as compared to untreated controlThesisItem Open Access Blue Mould Rot of Orange (Citrus reticulata Blanco) caused by Penicillium italicum (Wehmer) and its Management(2022) Choudhary, Meera; Rathore, G.S.Orange (Citrus reticulata Blanco) is an important citrus fruit belongs to family Rutaceae. Blue mould rot of orange caused by Penicillium italicum (Wehmer) fungus, is an important fruit rot, among all fruit rots of this crop and it reduces fruit quality. Survey was conducted in fruit markets of Rajasthan namely Jaipur, Chomu, Sikar, Ajmer, Alwar, Jhalawar and local market of Jobner and from each market, infected and healthy fruit samples were collected during the peak of its availability (January-April). Maximum blue mould rot incidence was recorded in Jobner fruit market (13.75 %) during 2020. Cork-borer injury method of fruit inoculation was found most effective in producing blue mould rot. The severity of blue mould rot was maximum at 25o C and at 100 per cent relative humidity. The total soluble solids, acidity, ascorbic acid, total soluble sugar, reducing and non-reducing sugar contents were significantly reduced in fruits having more than 75 per cent disease severity. Hot water treatment at 65o C revealed 29.12%, fruit wrapping with perforated paper (19.16%) and dipping of fruits in potassium metabisulphite solution (0.25%) + coating with paraffin wax (20%) were provided effective control (69.01%) of blue mould rot. Aerated steam at 52o C for 15 minutes was found highly effective (63.63%) in controlling fruit rot.Among five botanicals, extract of garlic cloves (10%) was found most effective in mycelial growth inhibition (89.74%) and reducing disease severity (53.30%). In six edible and non edible oils, eucalyptus oil (4%) was proved most effective in reducing mycelial growth (94.65%) and disease severity (50.63%). Among four bio-agents, Pseudomonas fluorescens was recorded highly effective in inhibition of mycelial growth (81.53%) and also checked the blue mould severity (61.46%) in orange. In five fungicides, captan (0.2%) was the most effective in reduction of mycelial growth (94.75%) and disease severity (79.71%) of blue mould rot of orange. Among four food preservatives, potassium metabisulphite (0.50%) was the most effective in inhibition of mycelial growth (85.60 %) of P. italicum and in reducing disease severity (64.05%). Among four homeodrugs, nitric acid (0.2%) was the most effective in inhibition of mycelial growth (91.61%) and disease severity (64.63%) of blue mould rot of orange. Among four plant growth regulators, gibberellic acid (200 ppm) was the most effective in inhibition of mycelial growth (89.46%) and disease severity (55.41%) of blue mould rot of orangeThesisItem Open Access Molecular Variability, Host Range and Management of Rhizoctonia solani (Kühn) causing Root Rot of Fenugreek (Trigonella foenum-graecum)(2022) SHEKHAWAT, DEEPENDRA SINGHRoot rot of fenugreek (Trigonella foenum-graecum L.) caused by Rhizoctonia solani has become an important constraint to the growers of fenugreek in Rajasthan. Disease incidence varied from 24.98 to 32.81 per cent in five surveyed districts of Rajasthan. Maximum disease incidence was recorded in Jaipur (32.81%) followed by Jhunjhunu (32.73%), Nagaur (29.81%), Ajmer (27.98%) and it was lowest in district Bikaner (24.62%). In Rajasthan, the overall average of disease incidence was 29.59 per cent in 150 fields of 30 villages of five districts. Isolation from infected roots yielded Rhizoctonia solani and proved pathogenic by soil inoculation technique. Significant morphological, cultural and pathogenic variability were observed among twelve isolates of Rhizoctonia solani collected from Jaipur, Jhunjhunu, Nagaur, Ajmer and Bikaner districts of Rajasthan. Twelve isolates of the pathogen, were coded as JPR Rs-1, JPR Rs 2, BKN Rs-3, BKN Rs-4, AJM Rs-5, AJM Rs-6, JJN Rs-7, JJN Rs-8, NAG Rs 9, NAG Rs-10, LCL Rs-11 and LCL Rs-12. Isolate JPR Rs-1 (Jaipur isolate) proved to be most virulent in causing root rot of fenugreek in comparison to other isolates. OPA markers were showed 81.81% (OPA5) to 100% (OPA2, OPA4, OPA7, OPA11 and OPA12) polymorphism, Highest marker index (0.66), heterozygosity index (0.66) and discriminating power (0.90) values were exhibited by OPA3 markerUnder host range studies, Rhizoctonia solani cause root rot in chick pea, chilli, coriander, fenugreek, cumin, wheat, barley, okra, field pea, tomato, fennel and cabbage but spinach was not infected. In all twenty five, genotypes / varieties of fenugreek were recorded minimum disease incidence in UM-208 and UM-209 genotype. Seven plant extract namely; mehndi, holy basil, clove, cinnamon, annise, giloy and ginger were evaluated against Rhizoctonia solani. Clove treated petri plate gave the maximum inhibition of mycelial growth and clove @ 10 per cent treated seed gave minimum disease incidence and highest yield of fenugreek. Under the different biocontrol agents i.e., Trichoderma harzianum, Trichoderma viride, Bacillus subtillis and Pseudomonas flurosence, Trichoderma harzianum resulted that maximum inhibition mycelial growth. T. harzianum @ 6 g kg-1 seed + Neem cake 250 kg ha-1 soil application showed minimum disease incidence and highest yield of fenugreek. All the tested seven fungicides namely; iprobenfos 48% EC, tebuconazole 25.9% W/W, propiconazole 25% EC, difenoconazole 25% EC, carboxin 37.5% + thiram 37.5% DS, hexaconazole 5% EC, and azoxystrobin 8.3% + mancozeb 66.7% WG were evaluated different concentration and resulted that tebuconazole 25.9% recorded maximum inhibition mycelial growth and tebuconazole @ 0.2% treated seed gave minimum disease incidence and highest yield of fenugreekThesisItem Open Access Molecular Variability in Alternaria sesami (Kawamura) Mohanty and Behera, Causing Alternaria Blight of Sesame and Its Management(2022) MAURYA, SHIVAM; Singh, MahabeerSesame (Sesamum indicum L.) is an oldest valuable oilseed crop and also known as the "Queen" of oilseeds due to its high quality edible oil. Sesame crop prone to various fungal diseases. Among these diseases, Alternaria blight of sesame caused by Alternaria sesami (Kawamura) is widespread and has continued to be the major constraints in the production and productivity of sesame. Surveyed data revealed that the maximum average per cent disease intensity was observed from Jaipur district with 44.09 per cent followed by Karauli (34.02%), Swai Madhopur (33.99%), Pali (30.21%), Jodhpur (22.96%), and Ajmer (22.89%). While minimum per cent disease intensity was observed from Bikaner district with 12.90 per cent. The pathogen associated with Alternaria blight disease of sesame was purified and identified as Alternaria sesami. Pathogenicity test of Alternaria sesami was proved through Koch‟s Postulates under pot condition by using artificial inoculation of the pathogen. Twenty eight isolates were collected from surveyed location and coded as AsPA1, AsPA2, AsPA3, AsPA4, AsSM1, AsSM2, AsSM3, AsSM4, AsJD1, AsJD2, AsJD3, AsJD4, AsKR1, AsKR2, AsKR3, AsKR4, AsBK1, AsBK2, AsBK3, AsBK4, AsAJ1, AsAJ2, AsAJ3, AsAJ4, AsJP1, AsJP2, AsJP3 and AsJP4. Amid all the isolates Jaipur isolate (AsJP1) was found most virulent and caused maximum per cent disease intensity (63.29%). While minimum per cent disease intensity was observed in Bikaner isolate i.e. AsBK4 (18.28%). Molecular diversity analysis was done through RAPD marker and by using 10 random primers from OPD series i.e. OPD 01-10. Primers OPD-03, OPD-04, OPD-08 and OPD-10 showed 100 per cent polymorphism and least polymorphism was observed with primer OPD 09 (95.34 %). In the similarity matrix, isolate AsPA1 was found to have a higher value of similarity coefficient (1.00) while, isolate AsSM2 was found to have a lower value of similarity coefficient (.036). Among assessed ISR compounds, lowest per cent disease intensity (27.50%) was recorded in plot treated with Salicylic acid along with maximum decrease in Per cent Disease Intensity over control (52.52%) and maximum yield increase over control (36.47%). In epidemiological studies, it was concluded that meteorological parameters viz., minimum temperature, relative humidity and total rainfall were found positively and significantly correlated with the disease intensity while maximum temperature showed negative correlation with the disease intensity during both the years. Among evaluated bioagents Trichoderma harzianum was found most effective with highest mycelial growth inhibition (71.11%) of test pathogen. Whereas, in field condition the lowest per cent disease intensity (40.55%) with maximum per cent decreased disease intensity over control (36.46%) was recorded with the application of Trichoderma harzianum along with significant higher seed yield. Among assessed fungicides under laboratory and field conditions, it was observed that the Metiram + Pyroclostrobin resulted per cent mycelial inhibition at 50 ppm, 100 ppm and 200 ppm concentration under laboratory condition with lowest per cent disease intensity (20.66%) and maximum per cent decreased disease intensity over control (66.01%) including significantly highest seed yield among all the treatments . Among tested botanicals under laboratory and field conditions, it was observed that Garlic at 15, 10 & 5 per cent concentration recorded best in mycelial growth inhibition under laboratory condition with lowest per cent disease intensity (29.37%) and maximum per cent decreased disease intensity over control (52.20%) including significant highest seed yield over control under field condition. Thirty varieties of sesame were screened under field condition against Alternaria blight disease of sesame. Among all the varieties, RMT-510 was found tolerant, While RT-125, RT-386, RT-388, RT-389, C-50, TKG-22, MT-107, RMT- 430, RMT-504, RMT-523, RMT-525, RMT-531, RMT-533, RMT-548, RMT-552, RMT-540 were found susceptible. Other 12 varieties i.e. RT-46, RT-54, RT-103, RT-127, RT 346, RT-351, RT-372, RT-385, RT-387, RT-391, GT-10 & Pragati were reported highly susceptible to Alternaria blight disease of sesame.ThesisItem Open Access Epidemiology, Variability and Management of Tomato Wilt Caused by Fusarium oxysporum f. sp. lycopersici (Sacc.) Snyder and Hansen(2022) CHOUDHARY,SUSHILA; Bagri,R. K.Tomato (Lycopersicon esculentum Mill.) is one of the most prevailing and important valued vegetable crops belonging to the family Solanaceae and grown all over the world. Tomato swayed by numerous biotic and abiotic stresses such as fungi, bacteria, viruses and nematodes that significantly affect its yield as well as quality. Among the fungal diseases, Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (Sacc.) Snyder and Hansen is regarded as serious pathological threats and caused considerable yield losses. A field survey was conducted during Kharif 2019 in four major tomato growing districts viz., Jaipur, Sikar, Tonk and Udaipur of Rajasthan. The maximum (22.63%) disease incidence was recorded in Jaipur and minimum (10.21%) in Udaipur district. The pathogen was isolated, purified and proved pathogenic by following Koch‟s postulates and identified as Fusarium oxysporum f. sp. lycopersici. Twelve isolates of F. oxysporum f. sp. lycopersici were collected and all isolates exhibited considerably variation in different cultural and morphological characteristics. The pathogenic behavior of all isolates was also varied from 20.52-78.98 per cent and isolate FOL-02 was found highly pathogenic with maximum (78.98%) disease incidence. Maximum mycelial growth and sporulation of F. oxysporum f. sp. lycopersici was recorded at 25 0C temperature, 90 per cent relative humidity and 6.5 pH. Potato Dextrose Agar medium was proved better for higher mycelial growth and sporulation. The accumulation of total phenol and protein contents were gradually higher after inoculation of pathogen. The higher accumulation of phenol and protein contents of plants were recorded in moderate resistant (Heemsohna and Abhilash) and minimum in susceptible (S-22 and Azad T-6) varieties. Among weather factors, the per cent disease incidence was positively correlated with maximum temperature whereas with other factors i.e. minimum temperature, morning and evening relative humidity and rainfall it was negatively correlated during both years (Kharif, 2019 and 2020). Out of 16 screened varieties, none was found free. However, seven varieties were moderately resistant, seven were moderately susceptible while two varieties were susceptible. On the basis of in vitro experiments the efficacy of neem leaf extracts @ 10%, Trichoderma harzianum and carbendazim @ 300 ppm were found most promising in inhibition of mycelial growth and reducing the disease incidence under pot conditions. Under field conditions, soil application of Trichoderma harzianum @ 2.5 kg/100 kg FYM/ha + root dip with carbendazim @ 0.1% for 30 min.+ drenching with carbendazim @ 0.1% at 35 DAT was proved effective in reducing disease incidence and in increasing fruit yield. However, the Incremental Cost Benefit Ratio was found best (1:37.88) with soil application of Trichoderma harzianum @ 2.5 kg/100 kg FYM/ha + root dip with carbendazim @ 0.1% for 30 min. due to lower cost of inputs.
