Thumbnail Image

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.

Browse

20191
Reset filters
Subject: Agricultural Meteorology × Author: Saikia, Raktim Jyoti × End date: 2019 × Thesis Type: M.Sc ×
Reset filters

Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    ThesisItemOpen Access
    IMPACT OF THERMAL AND RADIATION REGIMES ON GROWTH AND YIELD OF POTATO (Solanum tuberosum) UNDER VARYING MICROENVIRONMENTS
    (AAU, Jorhat, 2019-07) Saikia, Raktim Jyoti; Neog, Prasanta
    A field experiment was conducted during rabi, 2018-19 in the Instructional-Cum-Research (ICR) Farm of Assam Agricultural University, Jorhat to study the impact of thermal and radiation regimes on growth and yield of Potato under varying microenvironments. The cultivar Kufri Jyoti was grown in split plot design with four dates of planting (P1 - 10th Nov, P2 - 20th Nov, P3 - 30th Nov and P4 - 10th Dec) in main plots and mulches (M0 - non mulch, M1 - water hyacinth and M2 - black polythene) in sub-plots, following recommended agronomic practices. Microclimatic parameters like soil temperature (daily), soil moisture and photosynthetically active radiation (PAR) were recorded periodically. Occurrences of different phenological events along with periodic LAI, plant biomass, yield attributing characters and tuber yield were recorded. Phenophase-wise agroclimatic indices viz., growing degree days (GDD), heliothermal unit (HTU), day temperature, phenothermal index (PTI) and heat use efficiency (HUE) were computed following established procedure. The weekly maximum and minimum temperature throughout the crop growth period ranged from 21.3 to 27.2℃ and 8.1 to 16.1℃, respectively. A total of 110.7 mm rainfall from 16 rainy days was received during the growing period and weekly average BSSH ranged from 1.5 to 7.7 hr. The maximum soil moisture depth (mm) was recorded under water hyacinth (85.7 mm) followed by non-mulched (81.2 mm) and lowest under black polythene mulch (79.7 mm). Among different dates of plantings P1 recorded highest (83.3mm) soil moisture depth, followed by P4 (82.0 mm), P2 (81.8 mm) and P3 (81.5 mm). The weekly mean morning and evening soil temperature ranged from 13.6 to 19.3°C and 19.6 to 28.6°C, respectively under different planting dates and mulching treatments. Irrespective of planting dates, soil temperatures under black polythene was higher in morning and evening by 0.8 to 1.9°C and 1.5 to 2.8°C, respectively, while soil temperatures under water hyacinth were 0.3°C to 0.9°C higher in the morning and 0.5 to 2.2°C lower in the evening as compared to non mulched treatment. No considerable difference in incident PAR was observed among mulching treatments. However, it varied considerably when measured at different days in all planting dates. Irrespective of planting dates the reflected PAR increased in later growth period of the crop with the onset of senescence. The lowest (65 μ mol s-1 m-2) RPAR values under black polythene treatment were attributed to greater absorption by black surface. The transmitted PAR was lowest, when measured on 55 DAP with full coverage of canopy, after that it increased again with maturity of the crop. PAR interception was highest on 55 DAP (74.8 %) in all the planting dates and mulching treatments. Among the mulching treatments, crops under water hyacinth recorded highest (80.6%) interception of PAR. The duration of the crop was highest under first date of planting (100.33 days) followed by second (96.7 days), third (90 days) and fourth (87.6 days) date of planting. The maximum leaf area index (LAI) was observed under water hyacinth (2.77) followed by black polythene (2.44) and non-mulched (2.14) treatment. Maximum partitioning of photosynthates towards tuber was found in case of water hyacinth (386.77 g m-2) and lowest in non-mulched (241.63 g m-2). Highest average total dry matter accumulation was obtained in P1 (465.2 g m-2) followed by P2 (431.6 g m-2), P3 (309.6 g m-2) and P4 (284.8 g m-2). The tuber yield was found to be highest on P1 (135.6 q ha-1) followed by P2 (118.3 q ha-1), P3 (86.3 q ha-1) and P4 (60.0 q ha-1). The RUE for tuber yield was highest under water hyacinth (2.35 g MJ-1) followed by black polythene (2.03 g MJ-1) and non-mulched (1.67 g MJ-1) condition. From correlation study it was observed that tuber yield, biomass accumulation and LAI were found significant and positively correlated with PAR interception and RUE as well as with AGDD, AHTU, HUE and PTI. The predictive model have been developed by using stepwise regression to predict tuber yield from radiation and thermal indices with higher R2 value of 0.96 and 0.99, respectively.