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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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20181
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Subject: Sericulture × Author: Sahu, Bhupen Kumar × End date: 2019 × Start date: 2018 ×
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    ThesisItemOpen Access
    IMPACT OF ENVIRONMENTAL FACTORS ON POPULATION DYNAMICS OF GALL INSECTS INFESTING SOM (Persea bombycina King) AND SOALU (Litsea monopetala Roxb.) PLANT
    (AAU, Jorhat, 2018) Sahu, Bhupen Kumar; Dutta, L. C.
    The present study on population dynamics of gall insects infesting Som (Persea bombycina King.) and Soalu (Litsea monopetala Roxb.) plant in relation to the weather factors were carried out in the experimental field of Department of Sericulture, Assam Agricultural University, Jorhat and CMER&TI, Lahdoigarh during 2017-18. Results indicate that the gall insects are host and organ specific and they produce galls on only one species. The gall insect infestation starts with laying of tiny eggs on the upper surface of the leaves in both Som and Soalu plants. On hatching of eggs, the first instar nymphs of Pauropsylla beesoni and maggots of Asphondylia spp. initiate the process of gall formation. The initial gall formation stage is a minute colour change in the infested area which gradually developed into a gall structure. The fully developed gall structures observed on the leaves were light greenish in colour initially and later on changed to purplish red in Som plant and light greenish to dark greenish in Soalu plant. Finally, the adults emerged out from the galls by making tiny holes at the terminal end of the galls. Gall insects appeared throughout the year; however the incidence, population density, extent of damage and intensity of attack of the pest varied during different months of the year and reached a peak in the month of July. Correlation and regression studies were carried out between the incidence, population density, extent of damage and intensity of attack of gall insects with the weather parameters viz., temperature (maximum and minimum), relative humidity (maximum and minimum), total rainfall, number of rainy days and bright sunshine hours. Significant correlation was found with temperature (maximum and minimum), relative humidity (minimum) and total rainfall with gall infestation. Relative humidity (maximum) and bright sunshine hours showed negative relationship with population build-up whereas other environmental parameters showed positive relationship with gall infestation. Thus, it may be concluded that the gall insect, Asphondylia spp. on Som and Pauropsylla beesoni Laing on Soalu plant appeared throughout the year and were largely regulated by meteorological factors viz., temperature, relative humidity and rainfall in different months. Therefore, proper eco-friendly management practices, preferably conservation and inundative release of bio-control agents against the gall insect would be necessary to avoid the probable hazards created by inorganic pesticides. Therefore a detailed study on management of the gall insect population with different bio-control agents is the need of the hour.