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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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20211
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Subject: Entomology × Author: Dutta, Panchamika × Start date: 2020 × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    Effect of certain plant extracts against Tea looper; Hyposidra talaca Walker, Geometridae : Lepidoptera
    (AAU, Jorhat, 2021) Dutta, Panchamika; Gogoi, Inee
    Laboratory experiments were conducted in the Department of Entomology, Assam Agricultural University, Jorhat during 2018-2020 to evaluate the bioefficacy of five different plant extracts which had been extracted with cold water viz.,Sapindus saponaria, Annona squamosa, Lantana camara, Vitex negundo and Xanthium strumarium had been done against the larva of Hyposidra talaca. Different concentrations of plant extracts along with the untreated and a standard check (Deltamethrin 2.8 EC) were taken for comparison. The result reveal that the highest mortality of 90.0% at 10.00% concentration followed by 63.66%, 56.66%, 53.33%, 50% and 43.33% at 7.5%, 5%, 2.5%, 1% and 0.5% concentrations respectively at 72 hours after treatment when the larva were treated with X. strumarium. The data of A. squamosa showed lowest mortality of 56.83% at 10.00 % concentration followed by 53.5%, 46.8%, 40.1%, 36.76% and 20.03% at 7.5%, 5%, 2.5%, 1% and 0.5% concentration respectively at 72 HAT. The leaf extracts of all the five plant extracts reveals a dose and time dependent mortality over the exposure period. While investigating the toxicity of plant extracts, the LC50 values of, S. saponaria, A. squamosa, L. camara, X. strumarium and V. negundo were found to be 3.464%, 4.228%, 3.549%, 1.334% and 3.648% at 72 HAT. The order of toxicity with respect to LC50 of all the plant extracts was Agora (Xanthium strumarium)>Monisaal (Sapindus saponaria)>Gu phool (Lantana camara)>Posotia (Vitex negundo)>Custard apple (Annona squamosa). While evaluating the effect of LC50 of each plant extracts on growth and development of looper caterpillar, it showed a considerable changes in developmental duration. The developmental duration varied between 3.66days to 4.83days, 4.83days to 6.66 days, 5.33days to 7.66days, 5.00days to 6.66days, and 7.33days to 9.33days for L-I, L-II, LIII, L-IV and LV respectively with the different LC50 of different plant extracts. Highest larval duration in all the instars of larva were shown by LC50 dose of Xanthium strumarium and lowest duration was shown by LC50 dose of Annona squamosa. Even it showed delay in pupal duration of treated larvae. Deformed adults were formed. They failed to oviposit and the adults could not survive a single day.