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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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Now showing 1 - 9 of 118
  • ThesisItemOpen Access
    (2023) Goswami, Soumitra; Saikia, Ananta
    There exists a vast array of species, that have great potential but are often neglected and are termed as underutilized species. Underutilized fruits and vegetables are one such potential bio-asset, that could become a major tool in addressing global malnutrition, poverty and economic prosperity of millions of people. The present study covered assessment of nutritional and anti-nutritional constituents of 42 numbers of underutilized vegetables and fruits (28 vegetables and 14 fruits). The selected vegetables also showed significant variations in their biochemical constituents like moisture content (72.82 - 92.84 g 100g-1), ash content (3.82 - 15.37 g 100g-1), crude fat content (1.51 - 8.33 g 100g-1), crude fibre content (1.62 - 24.67 g 100g-1), crude protein content (1.80 - 9.79 g 100g-1%), potassium content (19.30 - 624.30 mg 100g-1), sodium content (2.34 - 234.11 mg 100g-1), calcium content (69.04 - 858.28 mg 100g-1), phosphorus content (25.94 - 579.15 mg 100g-1), iron content (31.34 - 401.34 mg 100g-1), zinc content (0.03 - 8.02 mg 100g-1), manganese content (25.36 - 264.59 mg 100g-1), Vitamin C (as Ascorbic acid content) (25.64 - 366.98 mg 100g-1), total phenol content (0.63 - 6.54 mg 100g-1) and free radical scavenging activity (72.31 - 95.09 %). The selected samples also contained anti-nutritional properties like saponin (0.13 - 1.08 mg 100g-1), tannin (0.23 - 2.79 mg 100g-1), phytic acid (0.16-0.61 mg 100g-1), oxalate (0.14 - 7.23 mg 100g-1). Similar to the vegetables, the selected fruits also showed significant variations in their biochemical constituents such as moisture content (68.96- 92.46 g 100g-1), ash content (1.39-5.38 g 100g-1), crude fat content (0.41-0.56 g 100g-1), crude fibre content (0.61–5.11 g 100g-1), crude protein content (0.51-8.99 g 100g-1),Potassium content (10.00- 982 mg 100 g-1), Sodium content (0.14 -70.99 mg 100 g-1), Calcium content (1.12-463.83 mg 100 g-1), Phosphorus content (4.57 -306.24 mg 100 g-1), Iron content (0.73 -163.30 mg 100 g-1), Copper content (0.14 -6.19 mg 100 g-1), Zinc content (0.24– 28.94 mg 100 g-1), Manganese content (0.15 -14.64 mg 100 g-1), Vitamin C (as Ascorbic acid content) (5.96 - 117.16 mg 100 g-1), total phenol content (21.08 - 900.84 mg GAE 100 g-1) and free radical scavenging activity (59.05- 94.73 %). The selected samples also contained anti-nutritional properties like saponin (0.01–7.98 mg 100 g-1), tannin (0.49–8.44 mg 100 g-1), phytic acid (0.32-8.05 mg 100 g-1) and oxalate (0.71 -28. 05 mg 100 g-1). However, after determining proportionate values of anti-nutritional components and their related nutrients showed lower than critical values for bioavailability of the related nutrients in majority of the selected fruits and vegetables. Hence, this study may be considered as a benchmark for planning future studies in the field of development of nutraceutical formulations in managing the issue of under nutrition and general wellbeing of the population.
  • ThesisItemOpen Access
    Floral behaviour, growth and post-harvest quality of Dragon fruit [Hylocereus costaricensis (Weber) Britton & Rose]
    (2023) Bagra, Gerik; Neog, Manoranjan
    An experiment was conducted on “Floral behaviour, growth and postharvest quality of dragon fruit [Hylocereus costaricensis (Weber) Britton & Rose] during 2019-20 and 2020-21 in the farm of KVK, Jorhat and Laboratory, Department of Horticulture, Assam Agricultural University, Jorhat with the objectives to study the floral behaviour, growth and development of dragon fruit and also the effect of various post-harvest treatments on its post-harvest quality and shelf life. The plants were tagged at bud initiation stage. The floral behaviour of the fruits was studied in the selected plants. The fruits were collected at 7 day intervals after flowering, till harvest for estimation of various physico-chemical parameters. Six post-harvest treatments; T1(Dipping fruits in ascorbic acid 500ppm solution for 5 minutes, air dried and packed in transparent 0.2% perforated LDPE bags), T2(Dipping fruits in 100 ppm sodium hypochlorite for 5 minutes, air dried and packed in transparent 0.2% perforated LDPE bags), T3(Dipping fruits in 1% Chitosan solution for 2 minutes, air dried and packed in transparent 0.2% perforated LDPE bags), T4(Dipping fruits in 1% Calcium Chloride solution for 30 minutes, air dried and packed in transparent 0.2% perforated LDPE bags), T5(Air dried fruits packed in transparent 0.2% perforated LDPE bags),T6(Air dried fruits were kept in open condition without packing and chemical treatment) were applied to fruits. Fruits were subjected to post harvest treatments after harvest and kept at ambient conditions (mean temp 30.5 0C and RH 82.5%). Physicochemical qualities were studied at 2 days, 4 days, 6 days and 8 days after storage (DAS). The laboratory experiment (Part II) was laid out in a factorial CRD with three replications. The flower bud initiation started in the second week of July and it took 18 days to flower. Anthesis started in the afternoon and the period lasted from 4.30 to 9.00 pm. The dehiscence of anthers took place 7 hours after opening of flowers. Pollen viability percentages were found to be 85.77±0.89 and 84.62±0.20 under 10x and 40x magnification, respectively. Fruits reached harvest maturity at 28 days after flowering when peel colour changed to pink red. At harvest, it recorded fruit weight 239.92 g, specific gravity 1.05, pulp:peel ratio 2.59 and the fruit contained TSS 11.95 0Brix, titrable acidity 0.26%, TSS:acid ratio 48.20, total sugar 8.12 %, crude protein 1.19 %, Crude fibre 0.84 mg/g, Total phenolics 51.94 mg GAE/g, Betalains 8.60 mg/100g. Physiological loss in fruit weight (PLW) were increased during storage. T2 recorded the lowest PLW (1.66%) and absence of rotting of fruits which was followed by T1. In T2 and T1, no fungal organism was detected. TSS and sugars were found to increase during storage while titrable acidity and ascorbic acid content decreased. T2 registered the lowest titrable acidity (0.16%) which was followed by T1 & T3 (0.18 %). Highest TSS (12.21 OBrix) and total sugars (8.30%) were recorded in T1 which had statistical parity with T2. Maximum retention of ascorbic acid (8.04%), Crude protein (0.72%), total phenolics (49.28mg GAE/100g), crude fibre (1.03%), Betalain (8.54mg/100g), total antioxidant (53.14 mg/g) were recorded in T2 which was followed by T1. Organoleptic qualities of fruits were found to decrease with the advancement of storage period. The highest organoleptic score values in respect of colour (7.89), taste (7.678), flavour (7.19) and texture (7.20) were obtained in T2 followed byT1. Maximum shelf life of 8 days was recorded in T2. Thus, it may be concluded that dragon fruit should be harvested at 28 days after flowering when peel colour is pink red, specific gravity (1.05), pupl:peel ratio 2.59 and TSS:acid ratio 48.20. Dipping fruits in 100 ppm sodium hypochlorite solution for 5 minutes, air dried and packed in transparent 0.2% perforated LDPE bags is the best treatment with minimum PLW, rotting and microbial activities retaining maximum sugars, ascorbic acid, crude protein, crude fibre, betalains, total antioxidant which extended the shelf life up to 8 days at ambient condition.
  • ThesisItemOpen Access
    Morphological, physico-chemical and molecular characterisation of mango (Mangifera indica L.) genotypes of Upper Brahmaputra Valley of Assam
    (2023) Hazarika, Binita; Kotoky, Utpal
    To study the extent of variation among the different mango genotypes of Assam, the present investigation entitled “Morphological, physico-chemical and molecular characterisation of mango (Mangifera indica L.) genotypes of Upper Brahmaputra Valley of Assam” was carried out during 2021-23 in Golaghat, Jorhat, Sivasagar and Tinsukia districts of Assam. A total of 100 accessions were surveyed out of which 33 accessions were finally selected based on acceptability. All the morphological characteristics were studied as per descriptor of IPGRI, Rome (2006). Results revealed significant variation in qualitative as well as quantitative traits. Tree height (tall, medium and dwarf) varied significantly among the accessions. Leaf features did not significantly differ between accessions, but flower color (yellowish green, yellow, and pink), panicle location (axillary, terminal, and terminal), and the presence of leafy bracts showed significant variations. Substantial differences in fruit shape (roundish, oblong, obovoid, elliptic) and fruit apex shape (round, obtuse, acute) were also observed. Stone and seed characteristics varied among the accessions with respect to type of veins on stone, quantity of fibre on stone, adherence of fibre to stone, seed shape and type of embryony. Quantitative characteristics of leaf, panicle, stone, seed and fruits also varied significantly among the accessions. Highest length:breadth ratio of leaf was observed in AMG-5 (8.89) and lowest in AMS-2 (2.78). Panicle length:breadth ratio was highest in AMS-7 (3.13) and lowest in AMJ-13 (1.04). The number of secondary rachis per panicle, sex ratio, number of fruits per panicle, per cent fruit drop and per cent fruit retention also varied. Study of physical characteristics of fruits revealed that accession AMG-2 had highest fruit weight 1206.48 g and 1197.92g both at harvest and at ripening respectively, whereas, fruit weight at harvest and ripening was lowest in AMG-5 86.31g and 75.67g, respectively. Similarly, significant variations were observed in characters like shape index, lenticels density, stone per cent, pulp: stone ratio, waste index and pulp percent. Study also revealed significant differences in chemical characteristics of fruit. TSS was highest in AMS-6 (18.80°Brix) and lowest in AMJ-13 (10.26°Brix). TSS: Acidity ratio was highest in AMJ-11 (91.00) and lowest in AMG-7 (24.50). Ascorbic acid content was highest in AMT-1(52.70 mg/100g) and lowest in AMJ-14 (22.63 mg/100g). Other chemical characteristics of fruits like total sugar, sugar:acid ratio, carotenoid content, moisture content also significantly varied among the accessions. The PCA for 55 quantitative characters in mango accessions revealed considerable variation among the accessions. 15 components displayed a total variation of 89.55% and were consequently considered to exhibit notable variance. 35 characters contributed to the 18.21% variation in PC1. Cluster analysis revealed maximum Euclidean distance of 17.10 that was observed between the two accessions of Golaghat, AMG-2 and AMG-8, and minimum Euclidean distance of 6.131 was observed between the two accessions of Sivasagar, AMS-3 and AMS-6 indicating that variation was influenced by genetic factor. Despite SSR markers demonstrating that there was no polymorphism, the occurrence of diversity in morphological and physiological traits necessitated additional molecular level studies using a wider array of markers. It can be concluded from the study of the accessions that there is considerable variation among them, and that accessions with distinguished characteristics can be exploited in mango improvement programmes.
  • ThesisItemOpen Access
    Standardization of crop geometry, fruit thinning and nutrient management in watermelon (Citrullus lanatus Thumb.)
    (2023) Deka, Bhabesh; Borthakur, Pritom Kr.
    The present experiment on ―Standardization of crop geometry, fruit thinning and nutrient management in watermelon (Citrullus lanatus Thumb.)‖ was carried out for two successive years during 2020-21 and 2021-22 in the farmer‘s field Nahat Chapani village, Teok, Jorhat (26°4816.8 North latitude and 94°251.1 East longitude) with the objective to optimize the planting density for maximum yield and quality, to study the effect of crop load on growth, yield and quality and to study the effects of integrated nutrient management on growth, yield and quality. The experiment was laid out in factorial Randomized Block Design with 3 factors viz. Spacing, Fruit thinning and INM with three replications and the data of individual years were subjected to pooled analysis. The spacing levels were D1 (2.5m x 2m), D2 (1.5m x 1m) and D3 (1m x 1m) where F1 (no thinning), F2 (Thinning up-to 1 fruits /primary vine) and F3 (Thinning up-to 2 fruits/primary vine) were the fruit thinning levels. A total of 4 INM treatment were given i.e. N1 (100% RDF), N2 (50% RDF + 50% RDN through FYM), N3 (50% RDF + 50% RDN through vermicompost) and N4 (50% RDF + 25% RDN through Vermicompost + 25% RDN through FYM). The treatments significantly influenced the various parameters except a few. The spacing D1 (2.5m x 2m) recorded the maximum days to flowering (25.59 days), maximum fruits/plant (3.93) and fruit weight (2.34 kg) leading to higher yield per plant (8.87 kg) although the spacing D3 (1m x1m) exhibited minimum days to flowering (25.59) and maximum yield (8.14 t/ha) owing to maximum plant population. Quality parameters were not affected significantly by distance. Fruit thinning significantly influenced the yield attributing and quality parameters. Fruit thinning level (F2) resulted in maximum fruit weight (2.92 kg) and yield (5.3 t/ha) which was at par with F3 (5.38 t/ha). Fruit quality was significantly improved by fruit thinning recording highest values of TSS (12.65 oB), total sugar (8.88%), reducing sugar (5.94%) and DPPH scavenging activity (54.57%). Among the INM treatments, N3 (50% RDF + 50% Vermicompost) was most effective with respect to growth, reproductive, physiological, quality and soil parameters viz., Highest fruits per plant (4.21), yield per hectare (6.26 t), TSS (13.10 oB), total sugar (9.14%), carotenoid (8.22 mg/100g), Lycopene (7.16 mg/100g), DPPH scavenging activity (54.86%), total chlorophyll (2.39 mg/g FW), soil available N (311.86 kg/ha), P (33.15 kg/ha), K (274.49 kg/ha) and organic carbon (1.19%). The interaction of three factors revealed that T35 (D3F3N3) recorded maximum production (10.05 t/ha) that was at par with T31 (D3F2N3) recording 9.82 t/ha yield. T7 recorded the highest values of fruit weight (3.2 kg), TSS (13.28 oB), total sugar (9.24%), carotenoid (8.3 mg/100g), lycopenne (7.19 mg/100g), and DPPH scavenging activity (54.97%) which was at par with T27 (D3F1N3), T31 (D3F2N3) and T35 (D3F3N3). Significantly higher values of soil available N (313.66 kg/ha), P (33.64 kg/ha) and K (295.69 kg/ha) was observed in T35 (D3F3N3). Computation of production economics revealed the B:C ratio to be the highest in D3F3N3 (6.53) which was at par with T31-D3F2N3 (6.35) and T27-D3F1N3 (6.12).
  • ThesisItemOpen Access
    Ornamental crop as a source of food and fabric colourant
    (2023) Bora, Aanmona; Kotoky, Utpal
    The experiment was conducted in the Laboratory, Department of Horticulture during 2020-2022, Assam Agricultural University, Jorhat to harness the dyeing properties of four locally available flower crop sources viz., Melastoma malabathricum and Gomphrena globosa for food colouring and, Calendula officinalis and Hibiscus rosa-sinensis for fabric dyeing, using their semi-dried petals. The extraction condition for melastoma pigment had been standardized at 510 nm in 25:75 (v/v) ethanol: water solvent concentration with a solvent-to-solid ratio of 15:1 (ml/g) at 80°C for 75 minutes and that of gomphrena pigment at 533 nm in 0:100 (v/v) ethanol: water solvent concentration with solvent-to-solid ratio of 5:1 (ml/g) at 40°C for 105 minutes. The total anthocyanin content of melastoma pigment was found to be fairly high, about 313.88 mg/L with a reasonably low degradation index of 1.20 and tinctorial strength of 4.05. The betacyanin content of gomphrena pigment recorded 270.23mg/L with a tinctorial strength of 6.71. The degradation for both the pigments followed first order reaction kinetics and the extracted melastoma pigment recorded a rate constant of 0.001857 min-1 with half-life of 396.67 min while, the gomphrena pigment recorded a rate constant of 0.003133 min-1 with a half-life of 223.34 min, which is notably good for a natural colourant. The ten week storage study of both melastoma and gomphrena pigments was best recorded at 4°C in dark (or refrigerated condition) to obtain a half-life of 384.97 days and 92.41 days, respectively meaning greater pigment stability and longer shelf-life as compared to their storage at room temperature (30±2˚C) in dark conditions followed by light, which accelerated the pigment degradation rates and drastically reduced their half-lives. For fabric colourant both Calendula officinalis and Hibiscus rosa-sinensis pigments were standardized for extraction at 430 nm in alkaline medium (1% Na2CO3 solution) at 90 and 45 minutes, respectively. The dye absorption percentage was recorded highest for dye: material concentration of 3g/100ml in both the pigment classes. The carotenoid content in calendula pigment was estimated to 270.23 mg/L and the total anthocyanin content in hibiscus pigment resulted in 209.10 mg/L. The dyeing time for calendula pigment was standardized at 30 minutes for cotton fabric and in silk at 60 minutes while that for Hibiscus pigment it was standardized at 90 and 30 minutes for cotton and silk fabrics, respectively. With alum as mordant the standardized mordant concentration for both calendula and hibiscus pigment-dyed cotton and silk fabrics recorded optimum results at 2% while with fresh tea leaves the optimum concentration was recorded at 1%. During standardization of mordanting time, both alum based calendula and hibiscus pigment-dyed cotton fabrics resulted best at 60 minutes and were further standardized for mordanting method i.e., pre-mordanting and simultaneous mordanting methods, respectively. Similarly, for their results upon silk fabric the optimum mordanting time was recorded at 45 minutes and, further standardized with simultaneous mordanting method in silk fabrics and pre-mordanting method in cotton. With fresh tea leaves as mordant, irrespective of the dye or fabric source used, the mordanting time was standardized at 15 minutes and the optimum mordanting method was evaluated as pre-mordanting method. Among the various treatment combinations calendula pigment-dyed and alum-mordanted silk fabrics resulted best for all the physical properties tested and fastness to washing, crocking and sunlight, followed by hibiscus pigment-dyed and fresh tea leaves-mordanted silk fabrics with excellent fabric thickness property and fastness to washing, pressing and perspiration. Thus, all the four locally available ornamental crop sources viz., Melastoma malabathricum, Gomphrena globosa, Calendula officinalis and Hibiscus rosa-sinensis, studied in the present investigation could be put forward as potential natural colourant sources for food and fabric dyeing.
  • ThesisItemOpen Access
    (2023) Kumari, Varsha; Saikia, Ananta
    A field experiment was conducted at the Experiment Farm, Department of Horticulture, Assam Agricultural University, Jorhat during the year 2022 to study the possibility of cultivating tomato on soilless growing media under a naturally ventilated polyhouse. The experiment was laid out in a randomized block design with 5 treatments and 4 replications. The treatments comprised of media containing cocopeat, vermiculite, perlite, sand and loam soil in various proportions. The study revealed that tomatoes were luxuriant on Loam soil: Sand: Vermicompost (1:1:1) medium with maximum plant height (140.68 cm), primary branches (6.19), plant fresh weight (177.90 gm), fruit weight (70.80 gm), crop duration (124.56 days), shorter duration to flowering (42.5 days), TSS (5.65 °Brix), minimum bacterial wilt infection (6.19 %) with final higher residual N, P, K contents of 2.58, 2.51, 2.64% respectively in the spent growing medium. Maximum plant dry weight (25.80 gm), fruit set (48.24%), fruits/cluster (8.36), fruits/plant (71.74), yield/plant (4.88 kg), total yield (66.26 q/500sqm), ascorbic acid (40.07 mg/100gm) and harvesting latitude (43.08 days) was recorded by Cocopeat: Sand: Vermicompost (5:2:3) medium, whereas the maximum days to first harvest (83.75 days) and blossom end rot incidence (45 %) were recorded by Cocopeat: Vermiculite: Perlite (3:1:1). Chlorophyll content (2.50 mg/100gm) and fruit volume (73.10 cc) were highest in Sand: Vermicompost (1:1). Flowers per cluster (3.91) and shelf life (12 days) were maximum in Cocopeat: Vermicompost (1:1). The economic analysis indicated that is Loam soil: Sand: Vermicompost (1:1:1) gave a maximum benefit-cost ratio of 2.20. These findings suggest that Cocopeat: Sand: Vermicompost (5:2:3) medium may be the preferred choice for optimizing growth and yield, although Loam soil: Sand: Vermicompost (1:1:1) is economically advantageous.
  • ThesisItemOpen Access
    (2023) Tonmoy, Tamuli; Gogoi, Bornali
    The present investigation was carried out in the Experimental Farm, Department of Horticulture, Assam Agricultural University, Jorhat during the period of 2022-23 to evaluate the performance of five rough lemon germplasms under transient waterlogged conditions. The experiment was laid out in Factorial Completely Randomized Block design with three replications consisting of five germplasm (G1, G2, G3, G4, G5), two inundation periods {I1(7 days) and I2(15 days)} and three flooding treatments {F1(75%), F2 (100%), F3 (125%)}. The germplasm were collected from different districts of Assam. The results revealed that at the end of I1, most plant biomass increased with G2 showing the highest increase. However, after end of I2, biomass reduction was observed, with G1 being the least affected. All germplasms showed higher reductions in biomass as flooding percentage increased, with F3 resulting in the maximum reduction. At the end of I1 there was an increase in root diameter except for some germplasm, root volume and number of adventitious roots. G4 showed the highest increase in root diameter, volume, and number of adventitious roots after I1 period. Root length was not affected by the inundation periods. In contrast, after I2 there was a reduction in root diameter, with G4 being least affected. However, root volume and number of adventitious roots increased for G4. Additionally, as flooding percentage increased, root diameter and growth decreased, with F3 causing the maximum decrease. Root volume and number of adventitious roots increased with increase in flooding % with F3 recording the highest increase. Chlorophyll content was negatively impacted by both inundation periods and percentage of flooding. G4 showed the least susceptibility to loss of chlorophyll at the end of 7 and 15 days. All germplasm showed reduced N, P, K, Zn, Mn, Cu content with the increase in inundation period and also percentage of flooding with I2 resulting in a higher reduction. G4 was the least susceptible to N, P and Zn loss overall. G5 had the least reduction in K, Cu and Mn content. Starch in leaves increased with prolonged inundation and higher flooding levels. G4 exhibited the highest content at treatment end. Conversely, starch content decreased with longer inundation and higher flooding levels. G4 was least affected at the end. Prolonged inundation and higher flooding levels led to increased leaf yellowing, wilting and leaf shedding. G4 showed the least number of yellow leaves, wilting and leaf shedding. G5 exhibited the best recovery potential among all germplasm, with the greatest root length after recovery. The plants showed better recovery after 7 days of inundation compared to 15 days. F1 resulted in the best recovery among the germplasm. From this investigation Germplasm 4 which was collected from Biswanath district (Rangamari) was found to be superior among all the germplasm in many morphological as well as physiological characters and thus G4 can be recommended for planting in waterlogging prone areas.
  • ThesisItemOpen Access
    (2023) Dhar, Sunita; Gogoi, Sailen
    The present study entitled “Impact of different organic manures on green fruits and seed production of Okra” was carried out to analyse the effect of different doses of organic manures viz., Farm Yard Manure (FYM), Vermicompost and Enriched compost alone or in combination with Microbial consortia on the growth characteristics, fruit yield and seed production. The experiment was conducted during 2022 in the Organic Block of Experimental Farm, Department of Horticulture, Assam Agricultural University, Jorhat-13 with treatments comprising of FYM 10 t/ha (T1), FYM 5 t/ha (T2), FYM 2.5 t/ha + Microbial consortia (T3), Vermicompost 5.0 t/ha (T4), Vermicompost 2.5 t/ha (T5), Vermicompost 2 t/ha + Microbial consortia (T6), Enriched compost 2.0 t/ha (T7) and untreated control (T8) which were applied at the time of final land preparation. The experiment was laid out in Randomised Block Design (RBD) with three replications. Height of plants was the highest under treatment T6 (Vermicompost 2 t/ha + Microbial consortia) whereas number of leaves, leaf area, stems girth, plant fresh weight and dry weight were recorded the maximum under T7 (Enriched compost 2.0 t/ha). The fruit yield parameters such as fruit weight (14.60 g), fruit volume (18.03 cc), fruit yield per plant (202.93 g) and total yield (95.74 q/ha) were also maximum under T7 (Enriched compost 2.0 t/ha). However, the highest Net Return of 2,08,800.00 per ha from tender fruits was produced with application of Vermicompost 2 t/ha + Microbial consortia (T6) leading to the maximum Benefit: Cost ratio of 3.80. The seed yield per plant, total seed yield, seed viability percentage was higher with treatment T6 while the lowest was recorded in T8 (Untreated control). The seed vigour at harvesting time and after 3 months of storage was the highest in Vermicompost 5.0 t/ha (T4) while Vermicompost 2 t/ha + Microbial consortia (T6) could retain higher vigour till 6 months of storage. Economic analysis of using organic manures for okra seed production showed FYM 2.5 t/ha + Microbial consortia (T3) to yield maximum B: C ratio of 6.32, followed by 6.09 with sole application of FYM @ 10 t/ha (T1). Thus, it can be concluded from the present experimental analysis that plant growth and fruit yield parameters were significantly enhanced by Enriched Compost 2 t/ha (T7) but was not statistically superior to Vermicompost 2 t/ha + microbial Consortia (T6). However, computation of production economics revealed that Vermicompost 2 t/ha + microbial Consortia (T6) to be the most remunerative for tender fruit production. For organic seed production and seed quality attributing characters, fortification of 2.5 t/ha of FYM with microbial consortia (T3) proved to be most profitable.
  • ThesisItemOpen Access
    (2023) KASHYAP, SRISHTTY; Pathak, Purnima
    Assam lemon, commonly known as “Kaji nemu” is an indigenous pride fruit of Assam. Due to the state's favorable climate, Assam lemons are readily available all round the year, with production peaking from April -September. This causes a market oversupply, which drives down the market price. Due to their physiological weight loss, these fruits are difficult store for an extended period. Moreover, fresh quality degrades along with the decrease in juice content across the storage. Therefore, focusing on juice processing Assam lemon fruit may assist to to prevent losses incurred by citrus growers as a result of the aforementioned issues. Based on this concept, the present investigation was framed and carried out to evaluate the shelf life of the processed Assam lemon juices in response to various treatments and to find out the economics of their preparation and preservation. Eight different treatments were prepared in matured (90-110 DAFS) and ripe (120-150 DAFS) lemon juices. Among the eight treatments T1 and T2 were untreated matured and ripe juice whereas T3, and T4 were treated with KMS. T5 and T6 were pasteurized and T7 and T8 were preserved by a combination of KMS and pasteurization in both matured and ripe juices, respectively. All the treatments were stored in refrigerated condition. The evaluation of the physico-chemical and sensory parameters was carried out for 180 days at intervals of 30 days while the microbial evaluation was carried out at intervals of 15 days. Regarding physico-chemical changes during storage of the Assam lemon fruit juices, samples T7 and T8 showed better results for TSS and titrable acidity which kept on increasing throughout the storage period whereas the pH and ascorbic acid kept decreasing. It was noticed that T8 had higher TSS and titratable acidity but lower pH and ascorbic acid content than that T7. The highest scores for overall acceptability, colour, mouthfeel, and taste were recorded in treatment T8 followed by T7 which showed means higher than the global mean on the initial day. The untreated, KMS-treated, as well as solely pasteurized juices, were discarded after 90, 120, and 150 days respectively after they crossed the microbial permissible limit. Highest B: C ratio was observed in treatment T2 (2.18) followed by T4 (2.16) as they had comparatively lesser treatment expenses. However, after considering the shelf life of the above treatments, they only persisted for 90 and 120 days, respectively. Interestingly, T8 had a B: C ratio of 1.78 but remained consumable for 180 days. Hence, it might be safe to establish that treatment T8 resulted in the highest shelf life with better retention of the physico-chemical and sensory parameters maintaining a decent B: C ratio. The investigation recommends that ripe Assam lemon juices given combined heat and chemical treatment can be effectively used to develop commercial Assam lemon juices with acceptable flavour and quality attributes.