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Assam Agricultural University, Jorhat

Assam Agricultural University is the first institution of its kind in the whole of North-Eastern Region of India. The main goal of this institution is to produce globally competitive human resources in farm sectorand to carry out research in both conventional and frontier areas for production optimization as well as to disseminate the generated technologies as public good for benefitting the food growers/produces and traders involved in the sector while emphasizing on sustainability, equity and overall food security at household level. Genesis of AAU - The embryo of the agricultural research in the state of Assam was formed as early as 1897 with the establishment of the Upper Shillong Experimental Farm (now in Meghalaya) just after about a decade of creation of the agricultural department in 1882. However, the seeds of agricultural research in today’s Assam were sown in the dawn of the twentieth century with the establishment of two Rice Experimental Stations, one at Karimganj in Barak valley in 1913 and the other at Titabor in Brahmaputra valley in 1923. Subsequent to these research stations, a number of research stations were established to conduct research on important crops, more specifically, jute, pulses, oilseeds etc. The Assam Agricultural University was established on April 1, 1969 under The Assam Agricultural University Act, 1968’ with the mandate of imparting farm education, conduct research in agriculture and allied sciences and to effectively disseminate technologies so generated. Before establishment of the University, there were altogether 17 research schemes/projects in the state under the Department of Agriculture. By July 1973, all the research projects and 10 experimental farms were transferred by the Government of Assam to the AAU which already inherited the College of Agriculture and its farm at Barbheta, Jorhat and College of Veterinary Sciences at Khanapara, Guwahati. Subsequently, College of Community Science at Jorhat (1969), College of Fisheries at Raha (1988), Biswanath College of Agriculture at Biswanath Chariali (1988) and Lakhimpur College of Veterinary Science at Joyhing, North Lakhimpur (1988) were established. Presently, the University has three more colleges under its jurisdiction, viz., Sarat Chandra Singha College of Agriculture, Chapar, College of Horticulture, Nalbari & College of Sericulture, Titabar. Similarly, few more regional research stations at Shillongani, Diphu, Gossaigaon, Lakhimpur; and commodity research stations at Kahikuchi, Buralikson, Tinsukia, Kharua, Burnihat and Mandira were added to generate location and crop specific agricultural production packages.

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20177
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Subject: Nematology × End date: 2017 × Start date: 2017 × Type: Thesis ×
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Now showing 1 - 7 of 7
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    ThesisItemOpen Access
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    ThesisItemOpen Access
    IDENTIFICATION AND MASS PRODUCTION OF ENTOMOPATHOGENIC NEMATODES
    (AAU, Jorhat, 2017-07) KALITA, RINKI MANI
    An experiment entitled “Identification and mass production of entomopathogenic nematodes” was conducted in the laboratory of Department of Nematology, Assam Agricultural University, Jorhat. A systematic survey was undertaken in Assam Agricultural University, Jorhat Campus for the occurrence of entomopathogenic nematodes during the year 2015-16. A total of 200 soil samples were collected randomly during the period November, 2015 to March, 2016 from four habitats (vegetation type) viz., Instructional-cum-Research (ICR) Farm, Experimental farm of Department of Horticulture, Experimental farm for plantation crops and Fallow land. From each habitat 50 numbers of samples were collected. Survey data revealed that out of 200 soil samples, eight samples were positive for entomopathogenic nematodes (4%), with containing 4 isolates were assigned the genus Steinernema (2%), 2 isolates were assigned to the genus Heterorhabditis (1%) and 2 isolates were assigned to the genus Oscheius (1%). Steinernematid isolates were designated as EPN-S-J-1, EPN-S-J-2, EPN-S-J-3. The isolates were found from rhizosphere of mung bean, arahar and cowpea respectively from ICR Farm, AAU, Jorhat. Another isolate of steinernematid (designated as EPN-S-J-4) was found from rhizosphere of citrus from the Experimental farm of the Department of Horticulture. One heterorhabditid isolate (designated as EPN-H-J-1) was found from rhizosphere of citrus and one isolate of Oscheius (designated as EPN-O-J-1) was found from rhizosphere of coconut in the Experimental farm of the Department of Horticulture. One heterorhabditid isolate (designated as EPN-H-J-2) and another isolate of Oscheius (designated as EPN-O-J-2) were found from tea garden of Experimental farm for plantation crops of AAU, Jorhat. Entomopathogenic nematodes were not recovered from the fallow land. EPN species were identified as Heterorhabditis bacteriophora, Steinernema aciari, Oscheius chongmingensis based on their morphological and morphometrical study of different life stages (infective juveniles, adults of both generations). The mass multiplication of three isolates Heterorhabditis bacteriophora, Steinernema aciari, Oscheius chongmingensis were done on different artificial media (plant and animal origin media). In plant origin media consisted of nine treatments including a control with three replications were laid out in a Completely Randomized Designs. The treatments were T1 (Wheat flour and sunflower oil), T2 (Wheat flour and soya oil), T3 (Wheat flour and coconut oil), T4 (Soya flour and sunflower oil), T5 (Soya flour and soya oil), T6 (Soya flour and coconut oil), T7 (Green gram flour and sunflower oil), T8 (Green gram flour and soya oil), T9 (Green gram flour and coconut oil) and control (Soya flour and corn oil). Among these treatments, T9 containing green gram flour and coconut oil which was found to be highest multiplication rate in all EPN specis viz., Heterorhabditis bacteriophora, Steinernema aciari, Oscheius chongmingensis 97.92 x 105, 114.17 x 105, 104.10 x 105 IJs/flask, respectively. Out of these EPNs spp. Steinernema aciari was found to be more yield (114.17x105) in T9. The medium containing wheat flour and sunflower oil (T1) recorded lowest multiplication rate for Oscheius chongmingensis (3.68 x105) and the medium containing wheat flour, soya oil (T2) recorded lowest multiplication rate for Heterorhabditis bacteriophora (5.19x105) and Steinernema aciari (2.67 x105). In animal origin media comprising of varied sources of proteins and lipids of animal origin and consisted of three treatments including a control with five replications were laid out in a Completely Randomized Designs. Treatments were T1 (Dog biscuit), T2 (Goat waste homogenate), T3 (Pork homogenate) and control (Chicken offal homogenate). Among these treatment, T3 containing pork homogenate which was found to be highest yield in three isolates viz., Heterorhabditis bacteriophora, Steinernema aciari, Oscheius chongmingensis were 6.54x105, 17.24x105, 5.99x105 IJs/100 flask respectively and more yield was found Steinernema aciari. T2 containing goat waste homogenate recorded the least multiplication rate of all three isolates viz., Heterorhabditis bacteriophora, Steinernema aciari, Oscheius chongmingensis were 3.67x105, 6.75x105, 3.47x105 IJs/100 flask, respectively.
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    ThesisItemOpen Access
    INTEGRATED MANAGEMENT OF Meloidogyne incognita AND Sclerotinia sclerotiorum DISEASE COMPLEX ON FRENCH BEAN (Phaseolus vulgaris L.)
    (AAU, Jorhat, 2017-07) Dutta, Ananya; Borah, A.
    In the present study on the interaction of Meloidogyne incognita and Sclerotinia sclerotiorum on French bean, the results indicated that the dual inoculation treatments significantly decreased plant growth parameters over the treatments with S. sclerotiorum @ 0.2% w/w and M. incognita @ 1000 J2/kg of soil. The treatment with M. incognita @ 1000 J2/kg of soil and S. sclerotiorum @ 0.2 % w/w simultaneous inoculation was statistically superior in decreasing the plant growth parameters of French bean. However, the number of galls, eggmasses and final nematode population in soil were found maximum in single inoculation treatment than dual inoculation treatments. The highest number of galls, eggmasses and nematode population were observed in the treatment with M. incognita @ 1000 J2/kg of soil. Maximum disease incidence was recorded in the treatment with M. incognita @ 1000 J2/kg soil + S. sclerotiorum @ 0.2% w/w after 15 days inoculation. Studies on the efficacy of biocontrol agent and chemicals against M. incognita and S. sclerotiorum disease complex on French bean under net house condition showed that all the treatments differed significantly over control in respect of increasing plant growth parameters. The seed treatments with T. harzianum @ 5ml/ kg + seed treatment with carbendazim 0.05% w/w + soil application with carbofuran @ 0.5 kg a.i/ha was found to be most effective in increasing plant growth parameters of French bean. All the treatments significantly decreased the number of galls, eggmasses and final nematode population in soil except control and the treatment with carbendazim @ 0.3% w/w. However, the treatment with carbofuran @ 1 kg a.i/ha was found to be best in suppressing the number of galls, eggmasses and final nematode population in soil. Maximum reduction in disease incidence was recorded in the seed treatment with T. harzianum @ 5ml/ kg + seed treatment with carbendazim 0.05% w/w + soil application with carbofuran @ 0.5 kg a.i/ha.
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    ThesisItemOpen Access
    Morphological and Morphometric variations of Genus, Paratylenchus and Macroposthonia in Assam
    (AAU, Jorhat, 2017-07) Hazarika, Namita; Das, Debanand
    The present investigations were carried out to study the morphological and morphometric variation of genus Paratylenchus and Macroposthonia from Upper Brahmaputra Valley Zone of Assam. Altogether 354 soil samples were collected from four districts of Upper Brahmaputra Valley Zone and Macroposthonia viz., Jorhat, Golaghat, Sivasagar and Dibrugarh from the rhizosphere of rice, maize, brinjal, banana, citrus and tea. The population of both the genera collected from four districts were identified as Paratylenchus curvitatus and Macroposthonia onostris. The present study revealed that ‘V’ ratio and stylet length were the stable characters (C.V. 1.16-4.89%) for Paratylenchus curvitatus while, body length, a, b, lip height and lip width, MB , basal bulb width, lip width are the least variable characters (C.V. 4.17-12%); c, c´, basal bulb are moderately variable character (C.V. 10.53-20.50%). The study on morphometric and allometric variations of Macroposthonia onostris from Upper Brahmaputra Valley Zone of Assam concludes that V ratio and MB ratio were the stable characters (C.V. 0.55-7.32%) for M. onostris while a, b c, c´, lip annules, Roes, Rex, Rv, Ran, are the moderately variable characters (C.V. 2.29-18.82%). Body length, R, Rst, Rvan are highly variable characters (C.V. 6.37-36.93%) for M. onostris.
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    ThesisItemOpen Access
    Exploitation of native biocontrol agents for the management of Meloidogyne incognita infecting okra.
    (AAU, Jorhat, 2017-07) Kurulkar, Uday J.; Bhagawati, B.
    Survey was conducted during 2014-15 for the isolation of native fungal biocontrol agents from eggmasses of Meloidogyne incognita infecting various crops in Assam. A total of 29 fungal isolates comprising of 7 genera with 9 species viz., T. harzianum, P. niphetodes, A. falciformi, F. oxysporum, F. solani, A. niger, A. flavus, V. leguminacea, Penicillium sp. were recovered from five different locations of Jorhat and golaghat district of Assam viz., Charigaon ,Alengmora, Danichopari, Namdeori and Barbheta. All the species showed varied relative frequency of occurance, F. oxysporum being the most frequently occurred species with 31.03 per cent of total fungal isolates. Further, these bioagents including unidentified species were evaluated for their efficacy on parasitism of eggs, egg hatch and juvenile mortality of M. incognita under in-vitro conditions. Among the bioagents T. harzianum, P. niphetodes, A. falciformi, F. oxysporum and F. solani were found to be egg parasitic in nature. However, the efficacy varied among bioagents and high percentage of egg parasitism, egg hatch inhibition and mortality of M. incognita juvenile with low LC50 value of culture filtrate at different exposure time were recorded in the bioagent T. harzianum and found to be best bioagent. Hence T. harzainum was selected for studying its efficacy against M. incognita under pot conditions. For this, T. harzianum was applied either as seed treatment and/or soil application or both. Carbosulfan as seed treatment and carbofuran as soil application were applied as chemical checks both either singly or in combination. The results showed that either T. harzianum or the chemicals (Carbosulfan and Carbosulfan) when applied together as seed treatment and soil application, significantly improved plant growth parameters of okra and reduced nematode multiplication as compared to when they were applied either as seed treatment or soil application. Application of chemicals either as seed treatment or soil application emerged as most effective treatment as compared to T. harzianum increase in plant growth parameter and reducing nematode multiplication. However, in respect of T. harzianum when applied together as seed treatment and soil application showed significantly better results in increasing in plant growth and reduction in nematode multiplication as compared that of the treatments with carbosulfan as seed treatment and carbofuran as soil application alone. Further, all the treatments significantly improved the plant growth parameters of okra and reduced the nematode multiplication from that of control.
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    ThesisItemOpen Access
    Occurrence and distribution of plant parasitic nematodes associated with tea gardens in Dibrugarh district of Assam
    (AAU, Jorhat, 2017-01) Gogoi, Hemanga Jyoti; Borah, A.
    The present investigations were carried out to know the occurrence and distribution of plant parasitic nematodes associated with tea plants of different tea gardens in Dibrugarh district. Soil samples were collected from different tea gardens of seven blocks from Dibrugarh district. Survey of plant parasitic nematodes revealed that eight genera of plant parasitic nematodes were found to be associated with tea plants of Dibrugarh district. The genera of plant parasitic nematodes recorded were viz., Helicotylenchus, Hoplolaimus, Tylenchorhynchus, Paratylenchus, Meloidogyne, Xiphinema and also nematodes genera found under tylenchs and criconematids. Community analysis of plant parasitic nematodes revealed that the genus Helicotylenchus ranked first in relative frequency, absolute frequency, absolute density, relative density and prominence value. The genus Hoplolaimus ranked second in relative frequency, absolute frequency, absolute density, relative density and prominence value. The genus Paratylenchus ranked third in relative frequency, absolute frequency, absolute density, relative density and prominence value. Studies on bio-management of root-knot nematode Meloidogyne incognita on tea under pot condition showed that all the treatments with Glomus fasciculatum, Trichoderma harzianum, Trichoderma viride, neem cake and carbofuran 3 G alone or in combination significantly increased plant growth parameters of tea and decreased number of galls, eggsmasses and final nematode population in soil over control. The maximum increase in plant growth parameters viz., shoot length, root length, fresh and dry weight of shoot and root were recorded with the treatment Glomus fasciculatum @ 300 spores/kg of soil + Trichoderma harzianum @ 4 gm/kg of soil + neem cake @15 gm/kg of soil. While, the maximum reduction of number of galls and egg masses and final nematode population in soil were recorded in the treatment with carbofuran 3G @ 3 g/kg of soil followed by the treatment with Glomus fasciculatum @ 300 spores/kg of soil + Trichoderma harzianum @ 4 gm/kg of soil + neem cake @15 gm/kg of soil which were at par. The treatment with Glomus fasciculatum @ 300 spores/kg of soil + Trichoderma harzianum @ 4 gm/kg of soil + neem cake @15 gm/kg of soil was found to be best in increasing plant growth parameters of tea and in decreasing number of galls, eggsmasses and final nematode population in soil over control.
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    ThesisItemOpen Access
    Preliminary screening of some botanicals on Brinjal (Solanum melongena L.) against Root Knot Nematode, Meloidogyne incognita
    (AAU, Jorhat, 2017-01) Bhuyan, Pranjal; Hazarika, Koilash
    Nematicidal activity of twenty one leaf aqueous extract of botanicals like Melia azadarach, Nycanthus arbor-tristis, Ocimum gratissimum, Piper betle, P. nigrum, P. hydropipper, Ricinus communis, Terminalia arjuna, Vitex negundo, Acarus calamus, Azadirachta indica, Bacopa monnieri, Annona squamosa, Psidium guajava, Mimosa pudica, Acorus calamus, Cymbopogon citratus, Pogostemon cablin, Ipomoea carnea, Mikania micrantha and Iberis linifolia were tested against Meloidogyne incognita to know their influence on as mortality and egg hatch inhibition under in vitro condition. The study revealed that all botanicals showed nematode toxicity by killing juveniles (J2) and inhibited egg hatch at 1, 5, 10 per cent concentration at 2, 4, 8, 12 and 24 hours of incubation but among them ten botanicals like A. indica, M. azedarach, P. nigrum, R. communis, M. micrantha, P. betle, O. gratissimum, C. citratus, N. arbor-tristis and P. hydropopper showed strong nematicidal activity and selected for pot experiment. In pot experiment 10 promising botanicals from in vitro test namely A. indica, M. azadarach, P. nigrum, R. communis, M. micrantha, P. betle, O. gratissimum, C. citrans, N. arbor-tristis and P. hydropipper evaluated for their efficacy to manage root-knot nematode problem on brinjal. The study revealed that all the plant extract showed strong nematicidal activity with increasing plant growth parameter of brinjal as compared to untreated control. Among the 10 botanicals the A. indica, M. azadarach, P. nigrum, P. betle and M. micrantha showed strong nematicidal activity against M. incognita, by reducing galls, eggmass/root system and egg/eggmasses with final neamtode population. These plant also increased plant growth parameters like plant height, shoot and root (fresh and dry weight) of brinjal. In the field experiment best five botanicals from pot evaluation such as A. indica, M. azadarach, P. nigrum, P. betle and M. micrantha were selected and evaluated against RKN on brinjal. These five botanicals showed nematicidal activity against M. incognita and improved plant growth parameters of brinjal under field condition as compared to untreated control. But among these A. indica showed maximum plant growth parameters with reduced nematode population.