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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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Subject: Crop Physiology × Author: Borgohain, Eshani ×
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    ThesisItemOpen Access
    RESPONSES OF SOME WHEAT (Triticum aestivum L.) GENOTYPES TO AEROSOLS OF NITROGEN
    (AAU, Jorhat, 2018-07) Borgohain, Eshani; Bharali, Bhagawan
    Wheat (Triticum aestivum L.) is one of the most important cereal crops globally, and it is a staple food for about one third of the world’s population. Cultivation of wheat has been the symbolic of green revolution that played pivotal role in making the nation a food surplus nation. The importance of wheat in Indian Agriculture is second to rice. The investigation into the effects of Nitrogen aerosols on some wheat (Triticum aestivum L.) genotypes (viz., 306, 1544, LOK-1, SHRI RAM-273), was accomplished both under field (October, 2016-March, 2017) and pot culture (October, 2017-March, 2018) at ICR farm and at the vicinity of Stress Physiology Laboratory, Department of Crop Physiology, Assam Agricultural University, respectively. The main objective of the investigation was to evaluate the physiological traits in wheat fertilized with Nitrate aerosols under field condition. The study, too, looked into the action mechanism of Nitrogen aerosol altering the physiology of wheat crop, and the relations between economic yield, physiological attributes and nitrogen status of wheat crop under the influence of aerosols. Treatments were applied at three stages viz., seedling, maximum tillering and spike initiation stages. The aerosols @ 400 ppm (≈40 kg N ha-1), were applied in three times i.e. 1200ppm or 1.2% (on sunny days in the afternoon (after 2–3 P. M.) when air temperature was low. In the field experiment, at maximum tillering and spike initiation stages, almost all the Nitrogen aerosols as compared to control increased the parameters significantly in a range viz., leaf area (8-13%) and (6-15%), LAI(19-31%) and (25.08-31.43%), SLW (11-26%), tiller numbers (14-28%) and (16-24%), effective tillers (19-31%), plant height (3-6%), rate of Pn (9-19%) and(10-16%), total chlorophyll content (14-34%) and (19-31%), chlorophyll a content (16-45%) and (23-35%), chlorophyll b content (14-33%) and (17-29%), NR activity (12-25%) and (23-36%), lipid peroxidase (6-53%) and (2-9%), CMS (14-28%), total carbohydrate content (18-28%), N content in grains (18-37%), NUE (26-39%), intercellular [K+] (13-31%), exchangeable [K+] (14-32%), intercellular [Ca2+] (11-28%) and exchangeable [Ca2+] (8-17%). The aerosols also increased the yield attributes such as no. of seeds per spike (2-7%), length of spike (14-24%), spike weight (14-18%), test weight (4-10%), harvest index (1.23-5.38%), biological yield (2-3%) and economical yield (3-8%). However, CMS was reduced non-significantly as compared to control at spike initiation stage. In the pot experiment, too, as compared to control, almost all the Nitrogen aerosols increased the parameters significantly in a range at maximum tillering stage and at spike initiation stages, respectively viz., leaf area (8-14%) and (4-10%), LAI (11-25%) and (11-21%), SLW (11-20%), tiller numbers (12-21%) and (10.68-16.66%), effective tillers (14.83-21.25%), plant height (5-8%), rate of Pn (16.78-23.43%) and (18-24%), total chlorophyll content (22-39%) and (26-33%), chlorophyll a content (22-43%) and (34-41%), chlorophyll b content (22-37%) and (23-30%), NR activity (14-28%) and (7.39-14.26%), lipid peroxidase (4-16%) and (2-9%), CMS (12-42%) and (12-26%), total carbohydrate content (7-16%), N content in grains (18-39%), NUE (25-42%), intercellular [K+] (21-44%), exchangeable [K+] (8-18%), intercellular [Ca2+] (7-24%) and exchangeable [Ca2+] (11-21%) . The aerosols also increased the yield attributes such as no. of seeds per spike (2-6%), length of spike (12-22%), spike weight (7-15%), test weight (5-9%), harvest index (2-7%), biological yield (2-7%) and economical yield (6-11%). In the field experiment, the variety LOK-1 possessed the highest score (25) followed by SHRI RAM-273 (10), and 1544 and 306 (2) considering their responses to the aerosols at maximum tillering, spike initiation and harvest stages. In the pot experiment, the variety LOK-1 possessed the highest score (28) followed by 1544 (4), SHRI RAM-273 (3) and 306 (2). However, based on the overall performance of the varieties at field and pot experiments together, the variety LOK-1 possessed the highest score (53) followed by SHRI RAM-273 (13), 1544 (6) and 306 (4). Thus, it could be concluded that the variety LOK-1 emerged as the most physiologically efficient one in the experiments. The physiological characteristics supporting the holistic performance of the variety LOK-1 especially are higher leaf area (12.90 cm2 plant-1) and (16.92 cm2 plant-1), LAI (1.63) and (0.99), effective tillers (2.69) and (3.89), rate of net photosynthesis (8699.76 ppm CO2 absorbed g-1d.w.h-1) and (9042.73 ppm CO2 absorbed g-1d.w.h-1), total chlorophyll content (2.48 mg g-1 fw of leaf) and (2.59 mg g-1 fw of leaf), chlorophyll a content (0.73 mg g-1 fw of leaf) and (0.80 mg g-1 fw of leaf), chlorophyll b content(1.68mg g-1 fw of leaf) and (1.73 mg g-1 fw of leaf), nitrate reductase activity (17.21 nmol NO2- g-1 fw of leaf hr-1) and (33.16nmol NO2- g-1 fw of leaf hr-1), CMS (0.17) and (0.65), carbohydrate content (147.63 mg g-1 dw) and (144.84 mg g-1 dw), intercellular [K+] (0.98 mg g-1 fw) and (1.07 mg g-1 fw), exchangeable [K+] (2.03mg g-1 fw) and (1.97 mg g-1 fw), intercellular [Ca2+] (1.66 mg g-1 fw) and (1.61 mg g-1 fw), exchangeable [Ca2+] (8.28 mg g-1 fw) and (8.28 mg g-1 fw), length of spike (10.78 cm) and (11.02 cm), spike weight (1.63 g) and (1.83g), test weight(47.15 g) and (4.57g), harvest index(69.42) and (51.57), biological yield (1.43 t ha-1) and (10.13 g plant-1) and economical yield(0.99 t ha-1) and (5.23 g plant-1) for field and pot respectively. Further as regard to the field application of N aerosols, KNO3 scored the highest (26) followed by Ca(NO3)2 (7), NH4NO3 (5), Control (0) considering the overall scores at maximum tillering, spike initiation and harvest stages. Similarly, in the pot experiment, KNO3 scored the highest (23) followed by Ca(NO3)2 (10), NH4NO3 (4), Control (0). However, based on the overall performance of the varieties at field and pot experiments together, the treatment KNO3 scored the highest (49) followed by Ca(NO3)2 (17), NH4NO3 (9), CONTROL (0). The correlation studies revealed that seed yield in LOK-1 was positively correlated with length of spike (0.63*, 0.97**), spike weight (0.69*. 0.09), harvest index (0.88**, 0.74*), biological yield (0.89**, 0.94*) and N content (0.80**, 0.94**) both for field and pot experiments respectively. In case of aerosol treatments, KNO3 was positively correlated with length of spike (0.97**, 0.55), test weight (0.88**), harvest index (0.96**, 0.79*), biological yield (0.78*, 0.76*) and N content (0.93**, 0.79*) at P (0.05)/ and P (0.01).