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.
Maize cultivation in the world is limited by diseases which cause grain loss of about 11% of the total production. Fungi are among the principal causes of deterioration and loss of maize grain. Fungi could cause damage to farmers maize during the storage if conditions are favourable for their development. A systematic study on effects of different storage structures on seed borne diseases of maize during storage with special reference to Assam, (Karbi Anglong) was conducted, because of the prevailing climatic conditions has been identified to cause a problem in storage of maize. Maize seeds of different varieties (white, yellow and red colour maize) locally cultivated were collected from different farmers of Karbi Anglong district and brought to the NSP (Crops) laboratory for further study. The seeds were stored in four different storage structures viz., metallic bin, gunny bag, HDPE bag and without storage structures as cobs with husk, cobs without husk and as seeds. Ten treatments comprising 4 storage structures replicated thrice and laid out in Completely Randomized Design (CRD). Data on germination, root and shoot length, colony count (Percent frequency) were collected at 3 months interval up to 270 days. It was observed that the percent frequency of pathogens were found to increase with increase in storage period. Five number of fungal pathogens were isolated and identified such as Aspergillus flavus, Aspergillus niger, Fusariumsp, Curvulariasp, Colletotrichum sp before storage and during storage. The pathogenicity test conducted revealed that the highest rotting of seeds was showed by Aspergillus flavus. The study also revealed that germination percentage and seedling vigour was maximum in seeds stored in metallic bins as compared to other storage structures. The present study therefore recommends that to store seeds in healthy state and to prolong the enhanced seed viability, seeds be stored in metallic bins.
Green gram(Vignaradiata) is one of the most important and most widely cultivated pulse crops in India. The knowledge of seed drying and storage mechanism of green gram crop is essential to minimize the loss and quality standards of the seed. The present study is a preliminary step for identification of storage potential of green gram variety Pratap. A laboratory experiment was carried out to evaluate the effect of drying temperatures on various seed quality parameters and evaluation of these quality parameters over subsequent storage period. The experiment was carried out in the Seed Technology and Research Laboratory of Assam Agricultural University. In the present study four different drying temperatures were used viz. 35°C, 40°C,45°C and 50°C and sun drying was taken as control. After a particular drying period (for each treatment different drying period), when it reaches the desired moisture content (8%, wet basis), the seeds were removed from the hot air oven and stored in HDPE (high density poly ethylene) interwoven bags.. Observations were taken at bimonthly interval and the final observations were taken at the nine months of storage. Based on the results it was found that drying at 50°C decreased the drying time by almost 50% compared to drying at 35°C but it was detrimental to embryo viability and germination. The highest germination, seed vigour index, seed viability and field emergence were found in the samples dried at 35°C which was at par with sun drying. The lowest pest incidence was observed in the samples dried at 50°C, whereas the highest pest incidence percentage was found in samples dried under sun and it was statistically different with all other treatments. However, with the increase in storage duration, the seed quality parameters were found to be decreased except pest infestation which was found to be increased. Although in most of the cases drying temperature 35°C was found at par with sun drying but due to unpredictability and inherent disadvantages along with resultant high pest infestation during storage it cannot be recommended. Thus, from the present study drying temperature of 35°C is recommended for drying and subsequent safe storage of green gram seeds.
An experiment was conducted during the kharif season of 2018 at Instruction cum Research Farm, Assam Agricultural University, Jorhat in split plot design with two seed rates in main plots and ten seed enhancement treatments in subplots replicated thrice. The seed enhancement treatments were also evaluated under laboratory conditions to study their effect on seed quality. All the characters in the laboratory evaluation, namely, speed of germination, seedling height, root length and seedling dry weight varied significantly except for the germination %. Results from the field experiment revealed significant variation among the treatments for all the characters, namely, field emergence (%), seedling height (cm), root length (cm), number of effective tillers, number of seeds/panicle, spikelet fertility (%), 100 seed weight (g), disease incidence (%) and seed yield (kg/ha) except days to 50% flowering. Interaction of the treatments with seed rates was significant for field emergence, seedling height, number of effective tillers, spikelet fertility and seed yield. The yield contributing characters, viz, number of effective tillers and spikelet fertility varied significantly under the two seed rates and showed better performance under the reduced seed rate than under the normal seed rate. Lower incidence of disease was recorded in respect of the treatments combinations with consortium of biocontrol agents (Trichoderma harzianum + Metarhizium anisopliae + Beauveria bassiana). Under both the seed rates, field emergence, seedling height, root length and seed yield showed better performance when treated with enhancements treatments along with a consortium of bio-control agents than those seeds which were treated with the enhancement treatments alone. The seed yield didn’t differ significantly between the two seed rates treatments. Hence, the results indicated that seed rate can be reduced to 56.25 kg/ha (75% of the recommended seed rate) without sacrificing performance in seed yield. Amongst all the treatments, Treatment 9 i.e. Ascorbate priming + Seed treatment with consortium of bio-control agents showed high values for the characters namely field emergence, 100 seed weight and seed yield with respect to the control. Disease incidence was also found to be the lowest in this treatment. Correlation studies revealed that the field emergence (%), number of effective tillers and number of seeds/panicle are significantly and positively correlated with seed yield (kg/ha), thereby indicating the importance of these characters in governing seed yield.
Rice is the world’s most important crop and is a staple food for more than half of the world’s population. Worldwide, rice is grown on 161 million hectares, with an annual production of about 744.4 million tons of paddy (FAO, 2014). Organic agriculture is a rapidly developing trend all around the world and more than 150 countries have adopted this technique and now produce organic food commercially. The most compelling reason for using organic seed when growing organic crops is that seed produced organically causes a less hazardous impact on the environment. Early crop establishment, lower productivity along with non- chemical disease management is a challenging task of seed technologist in organic seed production. Seed priming an effective seed invigoration method has become a common seed treatment to increase the rate and uniformity of emergence and crop establishment in most crops. Bio-priming is a process of a biological seed treatment that refers to the combination of seed priming and inoculation of seed with beneficial organism to protect the seed and improve the quality. In the present investigation, Beauverijal was found to be the best bio-agent for seed treatment as the results indicate better early seedling growth followed by higher no. of seeds/panicle and seed yield and less disease infestation. Early plant development and physiological functions could be impacted by early root growth reduction of disease incidence may also result in better yield performance. Commercial bio-agents viz. Trichojal and Metajal were also found to be effective in lowering the disease incidence and increase in seedling vigour followed by better yield performance. Comparative performance of cold adaptive PGPB (Trichoderma spp. + Bacillus spp.), Microbial consortium (C4) (Bacillus spp. + Pseudomonas spp.), Microbial consortium (C7, Bacillus spp. + Pseudomonas spp.), although designated as cold adaptive strains but does not impart any significant influence in enhancing seed vigour and early seedling growth. The colonization of the microbial agents in the rhizosphere region signifies its role in nutrient absorption and imparting abiotic stress resistance. The better adaptability of local commercial bio-agents in Trichojal, Metajal, and Beauverijal may lead to better performance in seed vigour, early seedling growth and final seed production.
Characterization of cultivars, establishment of varietal identity and genetic purity of the seed lots are crucial for varietal improvement, varietal protection and seed production. A rapid and reliable technique to verify the identity and to assess the purity of seed lots is important in seed quality assurance program. So, the present study was formulated to test 50 local varieties for genetic purity and group them based on the morphological similarities and response to various chemicals. The mean performance table of varieties based on quantitative traits revealed significant variation among the varieties for the quantitative traits. Based on the grain morphology, Black Rice (B), Nekeru and Pare were found to have long slender type of grain shape while Purubenu, Kola Konamasuri, Jeera Joha, Jengoni, Samraj, Vaboli Joha, Banki Sali, Basudev Bao and Bamkokua exhibited medium slender grain shape and Black Rice (G), Malbhog and Til Bora on the other hand, depicted basmati type grain shape. These three categories are highly preferred by the consumers due to its pleasant appearance. On the basis of chemical test, Bao, Sokua Bao, Samraj & Boga Ahu exhibited unique red colouration in the NaOH test. As per the phenol & modified phenol test, unique black colour was exhibited by Purubenu, Maniki Madhuri Joha, Joha Big and Kola Amona. The cluster analysis based on grain morphology revealed 4 predominant clusters, while based on chemical data, 2 distinct groups were obtained. Cluster I of the chemical data comprised of only one variety i.e. Sokua Bao while cluster II contained all the other varieties. This cluster could be further divided into 2 sub-clusters. The sub-cluster 1 comprised of all the Joha varieties except Jeera Joha while the sub cluster 2 encompassed all the Bao and the Black rice varieties indicating the two distinct amylose ranges. The most similar varieties with regards to the amylose content were Bao (9) and Pare. 16 varieties out of the total 50 varieties were found to have unique characters based on the morphological, chemical and biochemical parameters. These varieties are - Purubenu, Maniki Madhuri Joha, Joha Big, Kola Amona, Pare, Malbhog, Nekeru, Til Bora, Sokua Bao, Bao (9), Samraj, Boga Ahu, Black rice (B) and Black rice (G).