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ThesisItem Open Access Studies on effect of copper and silver nanoparticles on trichoderma spp.(Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, 2022-12-19) Deore, Pankaj Bhatu; Navgire, K.D.The beneficial soil microorganisms are important in maintaining soil health. The novel nano-pesticides and nano-fertilizers are introduced in agriculture to enhance crop production and productivity but after their use, they are leached out in the soil. Many researchers have reported the toxic effect of nanoparticles on various microorganisms and plants but very little data is available on the effect of NPs on beneficial microorganisms. Therefore the present investigation was carried out to explore the effect of Cu and Ag NPs on beneficial microorganisms such as Trichoderma. The green synthesis of Cu and Ag NPs were carried out by using Azadirachta indica leaf extract as a precursor and 1 mM aqueous solution of CuSO4.5H2O and AgNO3 respectively as a reducing agent in 1:5 proportion and incubated at 26 oC for 12 hrs and 24 hrs respectively. The color change reaction confirmed the formation of NPs. The NPs were purified by repeated washing and dried at 60 oC for 2 hrs. The powder form CuNPs and AgNPs were of coffee brown and dark gray color respectively. The green synthesized CuNPs and AgNPs were characterized by SEM, EDX, DLS and Zeta potential. The CuNPs and AgNPs appeared as nanoclusters crowded together with biomolecules but under higher magnification, they appeared spherical. The average particle size distribution of CuNPs and AgNPs was in the range of 141.8 to 3091 nm and 11.70 to 58.77 nm respectively with an average size of 1202 nm and 107.9 nm respectively. The green synthesized CuNPs were moderately polydispersed (0.286 PdI) and AgNPs were broadly polydispersed (0.602 PdI). The elemental composition of green synthesized CuNPs and AgNPs included 6.11 per cent of Cu and 48.63 per cent of Ag on a weight basis and 1.73 per cent of Cu and 15.14 per cent of Ag on an atomic percent basis. The green synthesized CuNPs and AgNPs were negatively charged with Zeta potential -6.54 mV and -4.38 mV respectively. The green synthesized CuNPs and AgNPs were evaluated against T. viride and T. harzianum. The CuNPs doses of 1-1000 ppm/L not affected the linear growth of T. viride and T. harzianum. The minimum inhibitory concentration of green synthesized AgNPs against T. viride was 100 ppm/L and 90 ppm/L against T. harzianum. The growth rate of T. viride was hampered by 1-1000 ppm/L doses of CuNPs in the initial growth period up to 48 hrs but later on, no effect of CuNPs was observed while AgNPs doses affected the growth rate erratically at 24 hrs, 48 hrs and 72 hrs. The 1-1000 ppm/L doses of Cu and Ag NPs variably affected the colony zone length of T. viride and T. harzianum but different doses of NPs not showed a consistent effect on colony zone length. The CuNPs and AgNPs doses variably affected the colony zone color of T. viride at 72 hrs (3rd day) and 96 hrs (4th day) as compared to the untreated control. The CuNPs doses not affected the colony zone color of T. harzianum at 72 hrs but at 96 hrs, only the productive zone showed variation in color as compared to the untreated control. In T. viride and T. harzianum at 96 hrs, the fuzziness gets increased in extending zone and productive zone respectively with an increase in CuNPs dose. The AgNPs doses affected the colony zone color of T. viride and T. harzianum at 72 hrs except extending zone of T. harzianum. At 96 hrs, only the fruiting zone of T. viride was not affected the colony zone color by 25 ppm/L, 50 ppm/L, 100 ppm/L, 250 ppm/L and 750 ppm/L doses of AgNPs but in T. harzianum only fruiting zone at 750 ppm/L and 1000 ppm/L and ageing zone at 1 ppm/L doses of AgNPs were unaffected the colony zone color. The CuNPs and AgNPs doses affected some cultural characteristics of T. viride and T. harzianum but not affected the colony form/shape, elevation, margin/border, opacity, conidiation and exudates on the colony at 72 hrs and 96 hrs. The 1-1000 ppm/L doses of CuNPs affected the colony color of T. viride but not affected the colony color of T. harzianum at 72 hrs and 96 hrs. All the doses of AgNPs affected the colony color of T. viride at 72 hrs but at 96 hrs, only 25-250 ppm/L doses not affected the colony color of T. viride while in T. harzianum only 1 ppm/L dose of AgNPs not affected the colony color at 72 hrs but at 96 hrs all the doses of AgNPs affected the colony color. The colony surface texture of T. viride and T. harzianum was woolly and not affected by any CuNPs at 72 hrs and 96 hrs but in T. harzianum, woolliness was increased at 96 hrs with an increase in the dose of CuNPs from 100 ppm/L to 1000 ppm/L. In T. viride, the AgNPs not affected the colony surface texture at 72 hrs but at 96 hrs only 1 ppm/L, 100 ppm/L, 750 ppm/L and 1000 ppm/L doses of AgNPs affected the colony surface texture while in T. harzianum, the 100-1000 ppm/L doses of AgNPs only affected the colony surface texture at 72 hrs but at 96 hrs, all the doses (1-1000 ppm/L) of AgNPs affected the colony surface texture of T. harzianum. The pigmentation of T. viride and T. harzianum was affected by 250-1000 ppm/L doses of CuNPs and 500-1000 ppm/L doses of AgNPs. Only the sporulation of T. viride was affected at 72 hrs by 1-1000 ppm/L doses of AgNPs. The colony ring formation in T. viride and T. harzianum was unaffected by 1-1000 ppm/L doses of CuNPs. The colony ring formation at 72 hrs was affected by some doses of AgNPs at 72 hrs in T. viride and T. harzianum. The colony ring formation at 96 hrs, was not affected by AgNPs in T. harzianum but in T. viride, 25 ppm/L, 100 ppm/L and 250 ppm/L doses of AgNPs only affected the colony ring formation. The colony reverse color of T. viride was affected by all the doses (1-1000 ppm/L) of CuNPs and AgNPs but 250-1000 ppm/L the doses of CuNPs and AgNPs affected the colony reverse color of T. harzianum. The 10-1000 ppm/L dose of CuNPs recorded the colony surface and back grooves in T. viride and 1 ppm/L dose of CuNPs in T. harzianum but the colony surface and back grooves of T. viride and T. harzianum were not affected by AgNPs. The CuNPs and AgNPs showed an inconsonance and consonance effect respectively on conidia production and conidia viability of T. viride and T. harzianum. In T. viride, 1 ppm/L, 25 ppm/L and 500 ppm/L doses of CuNPs and in T. harzianum, 1 ppm/L, 10 ppm/L, 50 ppm/L and 100 ppm/L doses of CuNPs hampered the conidia production and conidia viability as compared to untreated control while rest of all CuNPs doses promoted the conidia production and conidia viability in T. viride and T. harzianum. In T. viride and T. harzianum, the AgNPs affected the conidia production and conidia viability and with the increase in the dose of AgNPs, conidia production and conidia viability got decreased. The CuNPs and AgNPs showed a random effect on the volatile compound production of T. viride and T. harzianum which leads to the inhibition of FOL. The serial increase in the doses of NPs didn’t show any cumulative or noncumulative effect on the volatile compound production of T. viride and T. harzianum. The volatile compound production in T. harzianum was markedly get enhanced as compared to T. viride by the treatments of CuNPs and AgNPs. The volatile compound production of T. harzianum was enhanced by 1-1000 ppm/L doses of CuNPs while 1000 ppm/L, 750 ppm/L, 250 ppm/L, 25 ppm/L and 10 ppm/L dose of CuNPs only enhanced volatile compound production of T. viride. The volatile compound production of T. viride and T. harzianum was enhanced by the treatment of AgNPs as compared to the control except doses 25 ppm/L and 250 ppm/L in T. viride and 750 ppm/L in T. harzianum. The different doses of CuNPs and AgNPs showed a variable effect on the non-volatile compound production of T. viride and T. harzianum. An increase in the concentration of culture filtrates of T. viride and T. harzianum in each NP treatment showed a decrease in the linear growth of FOL and increased inhibition of FOL. In T. viride, the 1 ppm/L dose of CuNPs recorded the highest inhibition of FOL at 5 per cent, 10 per cent and 50 per cent concentration of culture filtrates and 10 ppm/L dose of CuNPs at 1 per cent and 25 per cent concentration of culture filtrates while 50 ppm/L dose of AgNPs recorded the highest inhibition of FOL at 1 per cent, 5 per cent, 10 per cent, 25 per cent and 50 per cent concentration of culture filtrates. In T. harzianum, the 750 ppm/L dose of CuNPs recorded the highest inhibition of FOL at 1 per cent, 5 per cent, 10 per cent, 25 per cent and 50 per cent concentrations of culture filtrates but at 25 per cent and 50 per cent concentration of culture filtrates all the CuNP treatments recorded lower inhibition of FOL than the untreated control while, 1 ppm/L dose of AgNPs recorded the highest inhibition of FOL at 1 per cent, 5 per cent, 10 per cent, 25 per cent and 50 per cent concentrations of culture filtrates. The CuNPs and AgNPs showed a variable effect on the antagonistic activity and inhibition zone of T. viride and T. harzianum. The CuNPs showed an increase in the antagonistic activity of T. viride and the highest inhibition of FOL was observed at 1000 ppm/L dose of CuNPs while only 1 ppm/L, 50 ppm/L and 250 ppm/L doses of AgNPs recorded an increase in the antagonistic activity of T. viride. The AgNPs recorded decreased antagonistic activity of T. harzianum while only 750 ppm/L, 1000 ppm/L and 10 ppm/L doses of CuNPs recorded an increase in the antagonistic activity of T. harzianum. The present investigations find out the effect of Cu and Ag NPs on T. viride and T. harzianum but further detailed investigations are needed to clearly understand the interactions of Cu and Ag NPs with T. viride and T. harzianum.ThesisItem Open Access Evaluation of trichoderma spp. In suppressing chickpea wilt with plant growth promoting traits(Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, 2022-12-08) Varala Krishnaveni; Navgire, K.D.Chickpea wilt caused by Fusarium oxysporum f. sp. ciceri, is a major loophole in the lesser productivity of chickpea. Biological control using native Trichoderma spp. isolated from rhizosphere soils is a sustainable solution to control soil borne disease. A total of 19 Trichoderma isolates were isolated from rhizospheric soils of chickpea from three agroclimatic zones of Marathwada region, Maharashtra and tested for its antagonistic efficacy under in vitro against virulent isolate of Fusarium oxysporum f. sp. ciceri. Among 19 isolates, eight Trichoderma isolates viz., CTP4, CTN2, CTJ1, CTA2, CTL2, CTO2, CTB1 and CTB2 were selected where per cent inhibition of pathogen ranged from 71.90 to 86.30 per cent. Based on morphological, cultural and molecular characters, Trichoderma isolates CTP4, CTN2, CTJ1, CTA2 and CTO2 were identified as Trichoderma yunnanense (CBS121219), isolate CTL2 as Trichoderma rifai (CBS130746), CTB1 isolate as Trichoderma simmonsii (CBS130431) and CTB2 isolate as Trichoderma pleuroticola (CBS124383). In the analysis of siderophore production, T. yunnanense isolates (CTA2, CTP4, CTJ1 and CTN2) and T. pleuroticola (CTB2) isolate were the significant producers of siderophore. Among them, T. yunnanense (CTP4 and CTN2) and T. pleuroticola (CTB2) confirmed as hydroxymate type, while T. yunnanense (CTA2) as carboxylate type of siderophore. Whereas T. yunnanense (CTJ1) confirmed as catecholate type of siderophore. In the analysis of IAA production, T. yunnanense isolates (CTA2, CTP4, CTJ1 and CTN2) were expressed greater amount of IAA concentration (87 to 116.00 µg/l) at 1 per cent concentration of L-tryptophan with 7 days of incubation in potato dextrose broth. Under in vitro germination test, seed biopriming with T. yunnanense (CTA2 and CTP4) proved best in increasing germination per cent and seedling vigour of chickpea seeds. In the estimation of micronutrient content in chickpea seedlings using atomic absorption spectrophotometry, application of Trichoderma isolates significantly improved micronutrient content after 30 days of sowing. Zinc content was recorded maximum in T. yunnanense isolates (CTA2, CTP4, CTJ1 and CTN2), Copper and Manganese content were recorded maximum in T. yunnanense isolates (CTA2, CTP4, CTJ1 and CTN2) and in T. pleuroticola (CTB2) isolate, whereas iron content was recorded higher in T. yunnanense isolates (CTA2, CTP4 and CTJ1). Under pot culture studies, T. yunnanense isolates (CTA2, CTP4, CTJ1 and CTN2) and T. pleuroticola (CTB2) isolate significantly improved plant growth parameters with maximum germination per cent, plant height, shoot length, root length, plant vigour, number of branches per plant, fresh weight of the shoot, dry weight of shoot, fresh weight of root, dry weight of root, number of nodules/plant, number of pods/plant, yield/plant with least wilt incidence in chickpea. In the analysis of Trichoderma mediated induced systemic resistance against challenge inoculation with Fusarium oxysporum f. sp. ciceri, T. yunnanense isolates (CTA2, CTP4 and CTJ1) and T. pleuroticola (CTB2) isolate shown profound potential in expression of defense enzymes i.e. peroxidases, polyphenol oxidases, chitinases and phenols. All enzymes activity and phenol content was low at 0 hrs. of pathogen inoculation and peroxidase & polyphenol oxidase activity gradually increased up to 72 hrs. Chitinase activity increased up to 96 hrs., however phenol content increased throughout the time till 164 hrs.ThesisItem Open Access Epidemiology and management of enation leaf curl disease of okra Abelmoschus esculentus (L.) moench)(Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, 2022-03-02) Kendre, Ashatai Hanumantrao; Gholve, V.M.Okra (Abelmoschus esculentus L. Moench) is an important and extensively grown vegetable crop. It is widely grown all over tropical, subtropical and warm temperature regions of the world. Okra can be grown on wide range of soils, but well drained fertile soils with adequate organic matter result to high yield It is a warm season crop and thrives best under hot and humid condition. Day temperature ranging from 25°C to 40°C and night temperature over 22°C is required for proper growth, flowering and fruit development. The okra plants are rich in minerals, carbohydrates, fibers, proteins, fats, phenols, and vitamins A, B, and C. Beside its economic importance, okra plants suffering due to number factors including diseases,insect pests and weeds. Among these, okra whitefly (B. tabaci) not only causes direct damage by sucking the sap but also act as vector of different viral diseases which always has been a serious problem in okra. Now-a-day okra enation leaf curl virus (OELCuV), a begomovirus, is an emerging serious constraint for okra production in Indiawhich could reduce the yield by 5-74 per cent. Therefore, present study entitled ““Epidemiology and management of enation leaf curl disease of okra (Abelomoschus esculentus (L.) Moench)”, was undertaken during, Summer, 2021-22-19 to 2012-23 at the Department of Plant Pathology, VNMKV, Parbhani (M.S.), India. This study comprised of the objectives viz., viz., symptomatology, virus-vector relationship, effect of weather parameters, host range and integrated disease management (In vivo) against the disease. The findings of these studies are summarized below. At initial stage of disease cycle showed only few scattered veins of 1 to 5 leaves were found thickened and gradually showed minute pin head enations on the abaxial part of leaves and small group of few veins were found thickened without curling of leaves or reduction in leaf size and fruit setting at initial stage of plant growth. The important symptom of ELCuD was curling of leaves in an adaxial direction was observed during second week of March. In later stages, minor leaf curling symptoms with little distortion of internodes and reduction in leaf lamina whereas, with the increase of disease severity, infected plants exhibited moderate leaf curling followed by severe vein thickening, little distortion of internodes and minor reduction in leaf size were observed. Severely infected plants exhibited severe vein thickening, leaf curling into cup-shaped and reduction in leaf size, deformed internodes and stunting of the plant with no and/or few fruit setting. Later leaves become thick and leathery in structure. The growth of infected plants was found retarded. Fruits from infected plants were observed as small and deformed and unfit for marketing. Results of molecular characterization of OELCuV revealed that the PCR amplification of viral genomic DNA extracted from OELCuV sample generated ~775 to 797 bp fragments. The okra enation leaf curl virus (OELCuV) gene of isolate under study was compared with other sequences from source of NCBI using multiple alignment programme. BLASTp analysis showed that isolates had highest nucleotide sequence homology up to 100 % with other NCBI site available data sequences. The comparative study showed that the 100% similarity as well as 100 % base query of Okra Enation Leaf Curl Viruses with available database sequence on NCBI portal and confirmed the field OELCuV isolate through molecular study. Virus vector relationship study revealed that single whitefly per okra plant were found effective for transfer enation leaf curl virus (ELCuV) and typical symptoms were appeared after a minimum mean incubation period of 39.00 days. The treatments T6, T7 and T8 with 10, 12 and 14 viruliferous whiteflies were produced 100.00 per cent ELCuD incidence, respectively. The disease incidence was highest for 10 days old inoculated seedling and decreased as increase in age of seedling. The maximum disease incidence (86.66 %) was observed in T1 within incubation period of 6.66 day followed by treatments T2 (80.00 %), T3 (64.44 %) and T4 (53.33%). Minimum acquisition access period AAP required for transmission of ELCuD by viruliferous whiteflies was 1 hour. The treatment T8 with 24 hrs AAP recorded highest (100.00 %) disease incidence followed by T7 (86.66 %), T6 (60.00 %) and T5 (46.66 %). It was also observed that as the acquisition access period was increased, the transmission percentage of disease incidence was also increased. The IAP required for transmission of ELCuD by viruliferous whiteflies was 30 min. The treatment T8 with 24 hrs IAP recorded highest (100.00 %) disease incidence followed by T7 (75.55 %), T6 (53.33 %) and T5 (40.00 %). It was also found that as the IAP was increased, the transmission percentage of disease incidence was also increased. The first count of whitefly population in the protected okra plots during Summer, 2021 and 2022 was recorded during 9th SMW. Whitefly population and disease incidence were ranged from 0 to 2.2 whteflies/leaf and 0 to 59.25 per cent, respectively. Application of first, second, third and fourth spray of Azadirachtin, Verticelium leccani, Imidacloprid and Pyriroxifen + Fenpropathin was undertaken during 11th, 13th, 15th and 17th SMW respectively. Correlation data of both the year reveals that high temperature with no or little rainfall favored the development of ELCuD of okra with the increase in whitefly population. The optimum temperature range for per cent disease incidence and whitefly population were observed from 30.3˚C to 39.8˚C. Per cent disease incidence and whitefly population were found decreased with increase in morning relative humidity with optimum range from 46 to 93 % whereas, evening relative humidity and bright sunshine hours did not showed any remarkable effects on whitefly population and per cent disease incidence. Multiple correlation coefficients between independent variables with per cent disease incidence and whitely population for protected okra plot were 0.943 and 0.943 and for non-protected okra plot were 0.971 and 0.978, respectively during Summer, 2021-22. Whereas, multiple correlation coefficients between independent variables with per cent disease incidence and whitely population for protected okra plot were 0.982 and 0.867 and for non-protected okra plot were 0.986 and 0.984, respectively during Summer, 2022-23. Whereas, the rest of variation might be due to unknown factors not included in the investigation. In case of host range study, among the ten hosts, only Okra (Abelomoschus esculentus) and Hollyhock (Althea rosea) were found hosts of ELCuV with 90 and 40 percent transmission, respectively. Whereas, other species under study did not showed any ELCuD symptoms. Among 13 integrated disease management treatments imposed against ELCuD of okra under natural field conditions all treatments were found effective over the untreated control. The whitefly population and disease incidence were observed minimum in T12 (Seed treatment of Thiamethoxam + Yellow Sticky Traps + Mulching with polythene sheet + Azadirachtin + Verticillium leccanii + Imidacloprid + Pyriproxyfen + Fenpropathrin). followed by T10 (Seed treatment of Thiamethoxam + Yellow Sticky Traps + Mulching with polythene sheet + Imidacloprid) The yield of various treatments was ranged from 3.55 to 14.24 t/ha and 2.17 to 13.73 t/ha during Summer, 2021-22 and 2022-23, respectively. Among the all treatments, significantly highest yield was recorded in treatment T12 followed by treatment T10 and T11 whereas, lowest yield was recorded in treatment T13.ThesisItem Open Access Effect of edaphic factors on chickpea wilt (Fusarium oxysporum f. sp. ciceri) (padwick) snyder and hans, and its management(Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, 2022-11-30) Mergewar, Ashish Ramesh; Mulekar, V.G.Chickpea (Cicer arientum L.) is the most important pulse crop cultivated in India and affected by many fungal and viral diseases and among all the diseases, wilt caused by Fusariumoxysporum f. sp. ciceri is one of the most common fungal pathogen which causes ultimate yield loss in chickpea crop. Fusariumoxysporum f. sp. ciceri is the soil as well as seed borne pathogen. The effect of edaphic factors and the ability of fungicides, bioagents, and organic amendments on Fusariumoxysporum f. sp. ciceri growth and management could be used as method of treating soil borne diseases. Hence, investigation was carried out on “Effect of edaphic factors on chickpea wilt (Fusariumoxysporum f. sp. ciceri) (Padwick) Snyder and Hans. and its management. The Fusariumoxysporum f. sp. ciceri was successfully isolated on PDA medium from naturally wilt affected chickpea crop. The organism was characterized by microscopic observations viz., micro-conidia, macro-conidia and chlamydospores as well as cultural characterstics the wilt symptoms such as drooping of petioles and rachis, yellowing and drying of leaves and finally complete death of plant were observed on artificially inoculated chickpea plant (Cv. JG 62) through sick soil method and proved pathogenicity test. Among the eight soil types, silt and clay loam soil types were found most effective in disease suppression with plant mortality of 29.62 % and 36.53%, respectively. Among all the soil pH levels tested in in vitro, 4.5 and 5.0 soil pH levels were found most effective in disease suppression with plant mortality of 43.58 % and 47.61, respectively. Among all the soil moisture levels tested, 20% and 25 % soil moisture levels were found most effective with least average seedling mortality of 21.42 % and 25 %, respectively. All those fungicides and bioagents evaluated in in vitro were proved to be potent antimicrobials, with significantly highest mycelial growth inhibition of F. oxysporum f. sp. ciceri, over untreated control. Among fungicides, Carbendazim 50% WP, Tebuconazole 25.9 % EC, Thiophanate methyl 70 % WP (each @ 500 & 1000 ppm); Mancozeb 75% WP, Carbendazim 12% + Mancozeb 63% WP and Captan 70% + Hexaconazole 5% WP (each @ 2000 and 2500 ppm) were found to be most efficient in inhibiting mycelial growth of F. oxysporum f. sp. ciceri. Among the bioagents tested Trichoderma hamatum, T. harzianum and T. virenswere proved to be superior, antagonists against F. oxysporum f. sp. ciceri, causing wilt of chickpea. Out of all the organic amendments tested decoction tested in in vitro, Groundnut seed cake and Neem seed cake were found most effective with highest mycelial growth inhibition of 73.05 % and 65.83 %, respectively over untreated control.ThesisItem Open Access Studies on pigeonpea dry root rot caused by macrophomina phaseolina (Tassi) goid(Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, 2022-11-30) Dudhe, Sanjyot Prabhakar; Mulekar, V.G.Pigeonpea (Cajanus cajan (L.) Millsp.) is one of the major pulse crop of tropical and sub-tropical region. It is cultivated by small and marginal farmers under rainfed condition because of its ability to tolerate against drought and residual moisture. It is affected by many fungal and viral diseases and among all the diseases, dry root rot caused by Macrophominaphaseolina is one of the most common fungal pathogen which causes ultimate yield loss in pigeonpea crop. Macrophominaphaseolina is the soil as well as seed borne pathogen. The effect of edaphic factors and the ability of fungicides, bioagents, organic amendments and plant extracts on Macrophominaphaseolina growth and management could be used as method of treating soil borne diseases. Hence, investigation was carried out on “Studies on pigeonpea dry root rot caused byMacrophominaphaseolina (Tassi) Goid.” The Macrophominaphaseolina was successfully isolated on PDA medium from naturally dry root rot affected pigeonpea crop. The organism was characterized by microscopic observations viz., septate mycelium and oval to round shaped sclerotia as well as cultural charactersticsthe dry root rot symptoms such as drooping and drying of leaves, the root system of such infected plant showed dark and extensive rotting, destroyed lateral roots, roots become brittle with shredding of the bark and easily peeled off were observed on artificially inoculated pigeonpea plant Cv. TS3R (Pinku) through sick soil method for proving pathogenicity test. Among the eight soil types, silt and clay loam soil types were found most effective in disease suppression with average seedling mortality of 21.87 % and 24.16 %, respectively. Among all the soil pH levels tested in vitro, 4.5 and 5.0 soil pH levels were found most effective in disease suppression with averageseedling mortality of 34.03 % and 35.43 %, respectively. Among all the soil moisture levels tested, 55 % and 50 % soil moisture levels were found most effective with least average seedling mortality of 28.71 % and 32.62 %, respectively. All those fungicides and bioagents evaluated in vitro were proved to be potent antimicrobials, with significantly highest mycelial growth inhibition of Macrophominaphaseolina, over untreated control. Among fungicides, Carbendazim 50% WP and Tebuconazole 25.9 % EC (each @ 500 & 1000 ppm); Mancozeb 75% WP, Carbendazim 25 % + Mancozeb 50 %WS,Carboxin 37.5 % + Thiram 37.5% WS, and Tebuconazole 50 % + Trifloxystrobin 25 % WG (each @ 2000 and 2500 ppm) were found to be most efficient in inhibiting mycelial growth of Macrophominaphaseolina. Among the bioagents tested Trichoderma asperellum, Trichoderma hamatum and Trichoderma harzianumwere proved to be strong, antagonists against Macrophominaphaseolina, causing dry root rot of pigeonpea. All those plant extracts and organic amendments evaluated in vitro were proved to be potent antimicrobials, with significantly highest mycelial growth inhibition of Macrophominaphaseolina, over untreated control.Among plant extracts tested invitro, Ocimumsanctum (Tulsi) and Azadirachtaindica (Neem)were found most effective with highest mean mycelialgrowth inhibition of 60.55 % and 50.83 %, respectively over untreated control.Among all the organic amendmentsdecoction tested invitro, Neem seed cake were and Safflower seed cake were found most effective with highest mean mycelialgrowth inhibition of 57.38 % and 52.77 %, respectively over untreated control.ThesisItem Open Access Exploration and management of chilli fungal root rot complex(Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, 2022-11-30) Karande, Saurabh Arun; Suryawanshi, A.P.Fungal root rot complex disease caused by Sclerotium rolfsii, F.solaniand Pythium aphanidermatumis one of the most destructive diseases of chilli, causing accountable losses in the tunes of 60-80, 35-50, 34-65 and 50-60 percent, respectively. Present investigations on the disease were carried out during 2021-22to fulfill the objectives viz., isolation, pathogenicity, in vitroeffect nitrogen sources, temperature and pH, in vitroevaluation of fungicides, bioagents,organic amendments, at the Department of Plant Pathology, College of Agriculture, Latur. The test fungiwere successfully isolated on Potato dextrose agar and its pathogenicity was proved on chilli cv. Parbhani Local under screen house condition by sick soil method. Among the three tested fungi maximum average mortality was recorded by S.rolfsii and Fusarium solani.Therefore, the further studies were carried out with these two fungi (S.rolfsii and F.solani). Out of the eightnitrogen sourcesevaluated against S.rolfsii,highest mycelial growth was recorded with Ammonium oxalate (90.00 mm), followed by Ammonium sulphate (73.00 mm), Ammonium nitrate (56.50 mm), Ammonium ferrous sulphate (55.50 mm). Whereas, significantly highest mycelial growth of F. solani was recorded with Ammonium oxalate (81.00 mm),followed by Ammonium nitrate (75.50mm), Potassium nitrate (64.00 mm). The effect of all the eighttemperature regimeson growth ofS.rolfsii,highest mycelial growth was recorded with 28OC (90.00 mm), 25OC (90.00 mm) and 30OC (90.00), followed by 20OC (75.00 mm) and 35OC (72.00 mm). Whereas, significantly highest mycelial growth of F. solani was recorded with 28OC (84.00 mm), followed by 30OC (82.00 mm) and25OC (72.00 mm). The effect of all the eightpH levelson growth ofS.rolfsii,highest mycelial growth was recorded with pH 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5 (90.00 mm), followed by pH 8.0 (67.00 mm). Whereas, significantly highest mycelial growth of F. solani was recorded with pH 4.0 (69.00 mm), followed by 4.5 (68.18 mm), 5.0 (64.83 mm), 6.0 (61.66), 5.5 (60.50 mm) and 6.5 (59.66 mm). All the fungicides, evaluated in vitro found fungistatic / antifungal to both pathogens (S. rolfsii and F. solani). However, the fungicides Propiconazole 25% EC, Difenoconazole 25% EC, Tebuconazole 25.9 % EC and Hexaconazole 5% EC, Chlorothalonil 75% WP, Zineb 75% WP, Captan 50% WP, Mancozeb 75% WP, Tebuconazole 50% + Trifloxystrobin 25 % WG, Metalaxyl 4% + Mancozeb 64% WP and Captan 70% + Hexaconazole 5% WP were most effective against S. rolfsii ; whereas, the fungicides viz., Thiophanate methyl 70% WP, Carbendazim 50% WP and Tebuconazole 25.9 % EC and Captan 70% + Hexaconazole 5% WP were most effective against F. solani. All the eight bioagents evaluated in vitro proved antagonists against both the fungi (S. rolfsii and F. solani). However, T. harzianum, T. asperellumandAspergillus niger were most effective against S. rolfsii ; whereas T. harzianum, T. koningii, Aspergillus niger,T. asperellumand T. hamatum weremost effective againstF. solani. Aqueous decoctions of organic amendments evaluated in vitro against both the fungi (S. rolfsii and F. solani). However, cotton oil cake, neem seed cake and mahua oil cake were most effective against S. rolfsii ;whereas karanj oil cake, sesame oil cake weremost effective againstF. solani.ThesisItem Open Access Exploring seed mycoflora of chilli and their management(Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, 2022-11-30) Naikare, Prerana Machhindra; Mulekar, V.G.Chilli (Capsicumannuum L.) is considered as one of the most important commercial spice crop. India is not only the largest producer but also the largest consumer and exporter of chilli in the market and prone to many seedborne diseases which causes seed rot as well as reduction in seed germination which results in huge quantitative and qualitative yield losses. Hence, present investigation was carried out on “Exploring Seed Mycoflora of Chilli and Their Management”. All seven seed health testing methods (SHT) employed viz., blotter paper method, 2, 4-D method, standard agar plate method, modified PDA method, seed washing method, seedling symptom method and towel paper method were found efficient and reliable for the detection of seedborne fungi viz., Colletotrichum capsici, Fuasriumsolani, Alternaria altarnata, Aspergillus niger, A. flavus, Penicillium sp. and Rhizopus sp. from chilli seeds of variety ParbhaniTejas, Byadgi, Guntur and Local. Among 14 fungicides (systemic, non-systemic and combiproduct) evaluated invitroviz., Carbendazim 50% WP, Azoxystrobin 23% EC, Difenoconazole 25% EC and Tebuconazole 25.9% EC (systemic), Propineb 70% WP, Carboxin 37.5% + Thiram 37.5% WP and Carbendazim 12% + Mancozeb 63% WP (non-systemic and combiproduct) were found most effective with highest mycelial growth inhibition against two major seedborne fungi viz., Colletotrichumcapsici and Fusariumsolani associated with the seeds of chilli. Among all bioagents evaluated invitro, Trichodermaharzianum and T. asperellum were found most effective with highest mycelial growth inhibition against Colletotrichum capsici and Fusarium solani, respectively. All the seven treatments evaluated in rolled towel paper and in polybag culture able to steadily increase germination percentage, root and shoot length, and ultimately seedling vigour index by reducing the effect of seed mycoflora and also suppress wilt incidence caused by Colletotrichum capsici and Fusarium solani by rolled towel paper method and in polybag culture.ThesisItem Open Access Study on dry root rot of chickpea incited by rhizoctonia bataticola (Taub.) butler(Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, 2022-11-30) Kshirsagar, Rahul Balbhim; Magar, S.J.Chickpea (Cicer arietinum L., 2n = 16) belongs to family Fabaceae,is an important pulse crop grown in India. A critical review of literature revealed that, a number of diseases caused by fungi, bacteria, viruses and nematodes are known, which lowers the quality and quantity of the product of this crop. Recent report indicated that, dry root rot (DRR) is an emerging potential threat to chickpea production.The dry root rot of gram is caused by Rhizoctonia bataticola (Taub.) Butler. (Synonym: Macrophomina phaseolina (Maubl.) Ashby.). The isolation of test pathogen was successfully attempted from the roots of chickpea showing dry root rot, by using tissue isolation method on PDA media. Pathogenicity of test fungus was proved by using sick soil method. The plant started drying from base to top from flowering stage, which confirmed the disease and finally,the whole plant died. Effect of various soil types on incidence of R. bataticola revealed that, in different soil type least average mortality was found in silt type of soil. However, highest average seedling mortality was observed in sandy soil type. Among soil moisture, least average per cent mortality was found at 50 per cent moisture level, highest average mortality was found at 15% soil moisture level. Among the sixteen fungicides evaluated in vitro (eight systemic each @ 500 and 1000 ppm and eight non-systemic or combi-product fungicides each @ 2000 and 2500 ppm). Among systemic fungicides, Carbendazim 50 % WP and Tebuconazole 25.9 % EC and consequently, resulted with the cent per cent mycelial growth inhibition. Among non-systemic / combi-product fungicides, Carboxin 37.5 % + Thiram 37.5 % WP and Captan 70 % + Hexaconazole 5 % WP consequently, resulted with the cent per cent mycelial growth inhibition of R. bataticola. Whereas, among bio-agents, Trichoderma harzianum, followed by T. hamatumand Metarrhizium anisopliae, respectively. Among, organic amendments,Safflower seed cake followed by Cotton seed cake, FYM and Groundnut seed cake, respectively were effective against R. bataticola.Experiment on integrated management of dry root rot of chickpea revealed that, highest reduction in average mortality was recorded in the treatment of Carbendazim 5 % WP (ST) @ 3.0 g + T. harzianum (ST) @ 10 g per kg seeds + Safflower seed cake (SA) @ 50 gper kg soil and this was followed by T. harzianum (ST) @ 10 g, Captan 70 % + Hexaconazole 5 % WP (ST) @ 3g/kg seed, respectively.ThesisItem Open Access Studies on variability and management of cauliflower leaf spot caused by alternaria brassicae (Berk.) sacc.(Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, 2022-11-28) Yewale, Aniket Rajendra; Hingole, D.G.Alternaria leaf spot caused by A. brassicae (Berk.) Sacc. is one of the most widely spread and destructive disease of cauliflower (Brassica oleracea var. botrytis), which accounts for about 20-80 per cent yield losses. Therefore, present investigations on A. brassicae were undertaken with the objectives viz., survey, symptomatology, isolation, pathogenicity, identification, morpho- cultural and pathogenic variation, in vitro efficacy of fungicides, bioagents and botanicals and integrated disease management strategies. The survey studies indicated that the Alternaria leaf spot disease (A. brassicae) was of common occurrence and distributed in two districts of Marathwada region. The pathogen was isolated successfully from the naturally diseased cauliflower plant specimens collected during survey which were purified and maintained for further studies. The typical symptoms of Alternaria leaf spot observed during survey, pathogenicity test and pathogenic variation were: small, circular, dark spot. As the disease progresses, the circular spots may grow to ½ inch or more in diameter and are usually gray, gray-tan, or near black in color.Spots develop in a target pattern of concentric rings.Infected leaves turn yellow and drop down. Pathogenicity of the test pathogen was proved by applying Koch's postulates and using susceptible local variety of cauliflower under controlled conditions of the screen house. Based on symptomatology, microscopic observations and pathogenicity test, the test pathogen was identified as Alternaria brassicae (Berk.) Sacc. and its further identity was confirmed. Isolates found from different area’s while surveying showed variation in respect of morphological, cultural and pathogenic characters. Morphological variability assessed by measuring conidial length(38.43umto 56.39um), breadth (6.00um to 9.60um) and number of transverse septa (4.33um to 5.67um). Cultural variability assessed by measuring radial growth (35.00 to 76.00 mm), colony character (cottony growth to fluffy growth), colony shape (circular and irregular) and colony color (olivaceous green to blackish). Pathogenic variability assessed by measuring the size of leaf spot (1 mm to 4 mm), color of leaf spot (black, brownish black to yellow), No. of days required for initiation of symptoms (12 to 18 days), percent disease intensity (30.85 % to 45.66 %) and Disease reaction (virulent to moderately virulent). Studies on in vitro evaluation of the fungicides, bioagents and the botanicals revealed that all the treatments significantly inhibited mycelial growth of the test pathogen over untreated control. However, systemic fungicides viz., Hexaconazole, Propiconazole, Difenoconazole (each @ 500 and 1000 ppm) recorded 96.49, 94.67 and 91.19 per cent inhibition, respectively and non-systemic and combi product fungicides viz., Carbendazim 25% + Mancozeb 50%, Carbendazim 12% + Mancozeb 63% and Mancozeb (each @ 2000, 2500 and 3000 ppm) recorded 94.44, 89.60 and 88.80 per cent inhibition of the test pathogen, respectively. Bioagents viz., T. viridae, T. harzianum and A. flavus recorded significantly highest inhibitions of 80.91, 67.62 and 65.84 per cent, respectively. Botanicals viz., A. sativum, A. indica and E. globulus causes significantly highest mean mycelial inhibition of 84.54, 78.66 and 70.29 per cent, respectively. The integrated disease management studies indicated that the fungicides viz., Hexaconazole and Carbendazim 25% + Mancozeb 50%, the bioagent T. viridae and T. harzianum, botanicals A. sativum and A. indica were most effective with minimum percent disease incidence, intensity and maximum per cent disease control over untreated control.
