Loading...
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

Search Results

Now showing 1 - 9 of 52
  • ThesisItemOpen Access
    RESPONSE OF HYBRID MAIZE (Zea mays L.) TO INTEGRATED NUTRIENT MANAGEMENT UNDER DIFFERENT MICROCLIMATIC REGIMES
    (2021) Gogoi, Tapan; Rinjumoni Dutta
    A field experiment entitled “Response of hybrid maize (Zea mays L.) to integrated nutrient management under different microclimatic regime” was conducted at Instructional-cum-Research (ICR) Farm, Assam Agricultural University, Jorhat during summer season of 2020 and 2021 with a view to study the effect of microclimatic regime and integrated nutrient management in maize and also the nutrient uptake by the crop and its availability in soil after harvest. The experiment was laid out in a split plot design with three replications. The treatments consisted of three microclimatic regimes viz., M1: 15th February, M2: 1st March and M3: 15th March and four INM viz., N1: 100% RDF (60-40-40 kg/ha) N2: 75% of RDN as inorganic + 25% RDN as vermicompost, N3: 75% of RDN as inorganic + 25% RDN as FYM and N4: 75% of RDN as inorganic + 25 % RDN as enrich compost. The soil of the experimental site was sandy loam in texture, acidic in reaction (pH 5.12 and 5.18), medium in organic carbon (0.65 % and 0.71 %), available P2O5 (22.68 kg/ha and 22.87 kg/ha) and available K2O (144.50 kg/ha and 147.60 kg/ha) while low in available N (229.47 kg/ha and 221.32 kg/ha) in 2020 and 2021 respectively. Experimental findings revealed that different microclimatic regime significantly influenced the growth parameters, yield attributing characters, kernel and stover yield, harvest index and uptake of N, P and K by maize. Among the different microclimatic regimes, crop sown on 15th March resulted in significantly higher values in almost all the growth characters (viz., per cent plant emergence, plant height, leaf area index, dry matter production per plant, crop growth rate, relative growth rate) as compare to the first date of sowing in both the years. Crop sown on 15th March recorded highest values in respect of yield attributing characters like number of kernel rows per cob, kernels per row, number of kernels per cob, weight of cob with husk and weight of cob without husk. Cob yield with husk and cob yield without husk were also significantly higher in 15th March as compared to 15th February sowing in both the years. The highest kernel yield was obtained in 15th March sowing (40.72 kg/ha and 41.30 kg/ha in 2020 and 2021 respectively), which was at par with crop sown on 1st March (39.37 kg/ha and 40.28 kg/ha) and significantly higher than 15th February sowing. The highest stover yield was also obtained in 15th March sowing (79.83 kg/ha and 80.42 kg/ha in 2020 and 2021, respectively). Harvest index was significantly higher in 15th March (33.82 % and 33.90 %) in 2020 and 2021 and was at par with crop sown on 1st March. The uptake of N, P, K by kernel and stover of maize and total uptake were also highest in 15th March sowing in both the years but N uptake by kernel, stover and total uptake remain statistically at par with 1st March. The effect of microclimatic regime on available N, P and K content in soil after harvest of the crop was found to be non-significant. All the integrated nutrient management practices were better as compared to recommended doses of fertilizers (RDF) in terms of growth, yield attributes and yield. Application of 75 % of RDN as inorganic + 25 % RDN as enrich compost (N4) gave significantly higher value in respect of growth parameters studied viz., plant height, leaf area index, dry matter production per plant, crop growth rate, relative growth rate than recommended doses of fertilizers in both the years and remain at par with 75% of RDN as inorganic + 25 % RDN as vermicompost (N2). Among the different integrated nutrient management practices, 75 % of RDN as inorganic + 25 % RDN as enrich compost (N4) proved superior in terms yield attributing characters like number of kernel rows per cob, kernels per row, number of kernels per cob, weight of cob with and without husk. Cob yield with and without husk were significantly higher in 75 % of RDN as inorganic + 25 % RDN as enrich compost (N4) than RDF, but remain at par with 75 % of RDN as inorganic + 25 % RDN as vermicompost (N2). During both the years of experiment, the kernel yield (41.33 kg/ha and 42.55 kg/ha), stover yield (80.00 kg/ha and 80.78 kg/ha) and harvest index (34.79 % and 34.47 %) were found to be significantly higher in 75 % of RDN as inorganic + 25 % RDN as enrich compost (N4) as compared to RDF which was statistically at par with 75 % of RDN as inorganic + 25 % RDN as vermicompost (N2). No treatment differences were observed in respect of number of cob per plant, length of cob without husk, 1000 kernel weight, shelling percentage and N, P, K content in grain and stover due to different integrated nutrient management. However, the available N and K content in soil after harvest of the crop were found to be significantly higher in the control over other treatments. From the economic analysis, it has found that crop sown on 15th March recorded the highest gross return (Rs 89,576.67 and Rs 90,860.00), net return (Rs 62,000.17 and Rs 63,283.50) and B-C ratio (2.35 and 2.40) in 2020 and 2021, respectively. In case of integrated nutrient management practices, the treatment combination of 75 % of RDN as inorganic + 25 % RDN as enrich compost (N4) recorded maximum gross return (Rs 90,933.33 and Rs 93,622.22) and net return (Rs 62,097.33 and Rs 64,786.22) in 2020 and 2021, respectively.
  • ThesisItemOpen Access
    PERFORMANCE OF RAJMAH BASED INTERCROPPING SYSTEM UNDER RAINFED SITUATION
    (2021) Rongpharpi, Nipika; Barua, N.
    A field experiment was conducted in the experimental field, All India Coordinated Research project on Dryland Agriculture, Biswanath Chariali centre, Biswanath college of Agriculture, Assam Agricultural University during the rabi season of 2020-21 to study the “Performance of Rajmah based intercropping system under rainfed situation”. The soil of the experimental site was sandy loam in texture, acidic in reaction (pH 4.98), medium in organic carbon (5.80 g kg-1), available N (330.10 kg ha-1), available K2O (171.35kg ha-1) and available P2O5 (23.26 kg ha-1). The experiment was laid out in Randomized Block Design (RBD) involving three (3) replications with thirteen (13) treatments consisting of five (5) crops (rajmah, toria, linseed, lentil and buckwheat) which were grown solely as well as intercropped in different ratios of 1:1 and 2:1 viz. T1: sole rajmah, T2: sole toria, T3: sole linseed, T4: sole lentil, T5: sole buckwheat, T6: rajmah + toria (1:1), T7: rajmah + linseed (1:1), T8: rajmah + lentil (1:1), T9: rajmah + buckwheat (1:1 ), T10: rajmah + toria (2:1), T11-rajmah + linseed (2:1), T12: rajmah + lentil (2:1) and T13: rajmah + buckwheat (2:1). The competitive behavior of component crops in different intercropping system was determined in terms of land equivalent ratio (LER), relative crowding coefficient (RCC), aggressivity (A) and monetary advantage index (MAI). The results revealed that rajmah+lentil (2:1) intercropping system (T12) was found to be more economical and highest monetary advantage index (6012.08). The same system had the highest aggressivity value (+1.19 & -1.19 respectively) followed by rajmah + linseed (2:1). The relative crowding coefficient was >1 in rajmah among the intercropping treatments indicating yield advantage compared with sole cropping except T6, T9, T10 and T13 treatments. Rajmah intercropped with lentil under 2:1 ratio recorded the highest land equivalent ratio (1.18) and rajmah equivalent yield (13.46 qha-1). Economic analysis of the intercropping system revealed the highest gross return (Rs. 96,912.00 ha-1), net return (Rs. 66,132.00 ha-1) and benefit:cost ratio (3.1) under rajmah + lentil (2:1) ratio.
  • ThesisItemOpen Access
    Performance of bud chip seedlings under integrated nutrient management in autumn planted sugarcane (Saccharum officinarum L.)
    (2021) Begum, Mahima; Ojha, N. J.
    A field experiment entitled “Performance of bud chip seedlings under different integrated nutrient management practices in autumn planted sugarcane (Saccharum officinarum L.)” was conducted at Sugarcane Research Station, Buralikson, Assam for two consecutive years 2017-18 and 2018-19. The experiment consisted of three crop establishment techniques in main plot viz., M1: Conventional method of planting M2: Planting of bud chip seedling at 90 cm x 60 cm, M3: Planting of bud chip seedling at 120 cm x 60 cm and five integrated nutrient management practices under sub plot viz., F1: 100 % RDF, F2: 100 % RDF + vermicompost @ 1 t ha-1 + green manuring (cowpea incorporation) + biofertilizers @ 10 kg ha-1 F3: 100 % RDF + enriched compost @ 1 t ha-1 + green manuring (cowpea incorporation), N4: 75 % RDF + FYM @ 5 t ha-1 + vermicompost @ 1 t ha-1 + green manuring (cowpea incorporation) + biofertilizers @ 10 kg ha-1 and F5: 75% RDF + FYM @ 5 t ha-1 + enriched compost @ 1 t ha-1 + green manuring (cowpea incorporation). The treatments were laid out in split plot design and replicated thrice. The soil of experimental plot was clay loam in texture, acidic in reaction (pH 5.46 and 5.48) and medium in organic carbon content (0.71 and 0.68%) and available K2O (194.33 and 187.66 kg ha-1), low in available N (231.42 and 226.77 kg ha-1) and P2O5 (19.28 and 18.64 kg ha-1) during 2017-18 and 2018-19, respectively. Experimental findings revealed that the most of the plant growth parameters were significantly affected by crop establishment techniques. The planting of bud chip seedling at 120 cm x 60 cm (M3) recorded significantly higher values of plant growth parameters viz., total number of shoots ha-1, number of shoots plant-1, plant height, root growth, above ground biomass, LAI, LAD and CGR throughout the crop growing period, but was at par with planting of bud chip seedling at 90 cm x 60 cm (M2) in respect of physiologically active leaves plant-1 and leaf area stalk-1 during both the years. However, in case of few growth parameters such as chlorophyll content, green seeker NDVI, crop canopy temperature and RGR, no significant variation was observed among the crop establishment techniques. The planting of bud chip seedling at 120 cm x 60 cm (M3) also revealed significantly higher values of most of the yield attributing parameters such as length of millable cane, number of millable canes, number of internodes millable cane-1, length of internodes, average cane weight and eventually the cane yield of both individual years 7 as well as in pooled analysis. Results revealed that planting of bud chip seedling at 120 cm x 60 cm (M3) produced significantly higher cane yield for both the individual years (123.20 t ha-1 during 2017-18 and 118.64 t ha-1 during 2018-19) as well as in pooled analysis (120.92 t ha-1). Similarly, significantly higher values of green top, trash as well as total biological yield were also obtained under the planting of bud chip seedling at 120 cm x 60 cm (M3). The same crop establishment technique (M3) also registered significantly higher CCS as well as jaggery yield during both the years, but did not exert any significant effect on juice quality parameters over other crop establishment techniques. Likewise, significantly higher uptake of nutrients by different plant parts as well as the whole plant was obtained under the planting of bud chip seedling at 120 cm x 60 cm (M3). However, no significant differences were observed in case of soil physico-chemical characteristics viz., soil pH and organic carbon during both the years. All the integrated nutrient management treatments produced significantly higher plant growth, root growth and physiological parameters over 100% RDF (F1). Application of 100 % RDF + vermicompost @ 1 t ha-1 + green manuring (cowpea incorporation) + biofertilizers @ 10 kg ha-1 (F2) produced significantly higher values in case of all the plant growth such as total number of shoots ha-1, number of shoots plant-1, plant height, leaf area stalk-1, dry weight of above ground biomass, root growth and other physiological parameters like LAI, LAD, CGR, and RGR. But in few parameters such as number of physiologically active leaves plant-1, chlorophyll content, canopy temperature and green seeker NDVI all the treatments were at par with each other except 100% RDF. The integrated supply of 100% RDF + vermicompost @ 1 tha-1 + green manuring (cowpea incorporation) + biofertilizers @ 10 kg ha-1 (F2) also recorded significantly higher results in case of yield attributing characters viz., length of millable cane, number of millable canes, number of internodes millable cane-1, length of internodes, average cane weight and finally resulted in higher cane, green top as well as trash yield. Results revealed that the integrated application of 100% RDF + vermicompost @ 1 t ha-1 + green manuring (cowpea incorporation) + biofertilizers @10 kg ha-1 produced the highest cane yield for both individual years (115.46 t ha-1 in 2017-18 and 111.11 t ha-1 in 2018-19) as well as in pooled analysis (113.28 t ha-1) which was at par with all other treatments, but superior over 100% RDF. Similarly, significantly 8 higher green top as well as trash were also obtained under the treatment receiving 100% RDF + vermicompost @ 1 t ha-1 + green manuring (cowpea incorporation) + biofertilizers @ 10 kg ha-1 (F2) for both individual years as well as in pooled analysis. The same treatment (F2) also recorded the significantly higher biological yield (142.08 and 136.78 t ha-1), commercial cane sugar (14.62 and 13.95 t ha-1) and jaggery yield (10.67 and 10.13 t ha-1) during both the years. But except CCS%, the integrated nutrient management treatments failed to exert any significant effect on other juice quality parameters like field brix content, juice recovery and purity %. The N in content in all the plant parts viz., cane stalk, green top, trash and K content in cane stalk was significantly influenced by integrated management practices and maximum values were obtained due to application of 100% RDF + vermicompost @ 1 t ha-1 + green manuring of cowpea + biofertilizers @10 kg ha-1 (F2). Significantly higher N, P and K uptake by cane stalk, green top, trash as well as whole plant were also obtained under integrated application of 100% RDF + vermicompost @ 1 t ha-1 + green manuring of cowpea + biofertilizers @10 kg ha-1 (F2). All the integrated nutrient management practices significantly influenced the soil physico-chemical and biological characteristics over 100% RDF. The application of 75% RDF + FYM @ 5 t ha-1+ vermicompost @ 1 t ha-1 + green manuring (cowpea incorporation) + biofertilizers @ 10 kg ha-1 (F4) produced the highest soil organic carbon (0.85 and 0.84%), fungal (5.44 x 104*cfu g-1 and 5.38 x104*cfu g-1) and bacterial population (6.51x106*cfu g-1 and 6.45 x 106*cfu g-1) as well as available N and P2O5 in soil during both the years. The interaction effect was found to be significant in few growth parameters like total number of shoots, number of shoots plant-1 and leaf area duration. The planting of bud chip seedling at 120 cm x 60 cm along with 100 % RDF + vermicompost @ 1 t ha-1 + green manuring (cowpea incorporation) + biofertilizers @10 kg ha-1 (M3F2) recorded the highest values in the above parameters. In case of economics the higher gross return (` 3, 82,906 ha-1 and ` 3,67,546 ha-1), net return (` 2,62,388 ha-1 and ` 2,45,628 ha-1) as well as B-C ratio (3.18 and 3.01) was also recorded under the planting of bud chip seedling at 120 cm x 60 cm along with 100% RDF + vermicompost @ 1 t ha-1 + green manuring (cowpea incorporation) + biofertilizers @10 kg ha-1 (M3F2) during both the years.
  • ThesisItemOpen Access
    Bio-ethanol production from sweet Sorghum varieties under different Establishment methods
    (2022) Rao, Guntamukkala Babu; Goswami, Jogesh
    Sweet sorghum (Sorghum bicolor (L.) Moench) is a biofuel crop which can be grown year round without sacrificing food and fodder security. A field experiment entitled “Bio-ethanol production from sweet sorghum varieties under different establishment methods” was conducted at the Instructional-cum-Research Farm of Assam Agricultural University, Jorhat during two consecutive rabi seasons of 2018-19 and 2019-2020 with a view to evaluate the performance of different sweet sorghum varieties under different methods of establishments for ethanol production . The treatments consisted of four levels of sweet sorghum varieties viz., V1 - SSV 84, V2 - ICSV 93046, V3 - Madhura and V4 - CSH 22SS and three levels of establishment methods viz., M1- Direct sowing, M2 - Transplanting, M3 – System of Sorghum Intensification (SSI), laid out in a factorial randomised block design and were replicated thrice. The soil of the experimental site was sandy loam in texture, acidic in reaction (pH 5.25), medium in organic carbon (0.65%), available N (228.14 kg/ha), available P2O5 (21.20 kg/ha) and available K2O (125.75 kg/ha). The results from two year trial indicated that out of four sweet sorghum varieties evaluated, sweet sorghum variety CSH 22SS outperformed well in terms of growth attributes (plant height, no. of leaves plant-1, stem weight, stem girth, millable cane yield, total biomass) during both the years of experimentation. In case of ethanol attributes viz. brix, sucrose, reducing and total sugars were significantly higher in CSH 22SS for both the year 2018-19 and 2019-20, respectively. The CSH 22SS has also shown its superiority in achieving higher yield attributing parameters such as length and weight of earhead. The CSH 22SS had resulted significantly highest grain yield of 1.97 t ha-1 and stover yield of 4.48 t ha-1 when pooled for two years. Pooled analysis of juice yield (9262.66 l ha-1) and ethanol yield (646.89 l ha-1) were found to be significantly affected by the CSH 22SS. In case of nutrient content and uptake by grain and stover of sweet sorghum, highest values were recorded in CSH 22SS for both the years. Different establishment methods brought about significant differences in growth parameters, ethanol attributing parameters, yield attributing characters, yield, N, P and K uptake in sweet sorghum. The highest values in all such aspects as well total return and B: C ratio was recorded in SSI followed by transplanting method. Among the methods of establishment, the SSI resulted in significantly higher growth characters, ethanol attributes, yield attributing characters. The SSI recorded the highest pooled juice yield, ethanol yield, grain yield and straw yield of 8698.16 l ha-1, 614.50 l ha-1, 2.04 t ha-1 and 4.48 t ha-1 of sweet sorghum respectively. Also NPK uptake by grain and stover were significantly higher in SSI for both the years. In terms of economics, maximum mean gross return of Rs. 111088.50 ha-1, net return of Rs. 77482.53 ha-1 and B:C ratio of 3.29 was recorded in the CSH 22SS among the different variety treatments. The SSI method of establishment recorded maximum mean gross return of Rs. 112045.40 ha-1, net return of Rs. 77705.36 ha-1 and B:C ratio of 3.26 in sweet sorghum. The interaction effect of sweet sorghum varieties and methods of establishment were found to be significant in case of pooled juice yield (10879.33 l ha- 1) and ethanol yield (784.11 l ha-1) by V4M3 i.e. CSH 22SS in combination with SSI method of establishment. The economic returns viz. the maximum mean gross returns (Rs. 121611.40 ha-1), net returns (87221.37 ha-1) and B:C ratio (3.53) were also recorded in the V4M3. It could be concluded that for obtaining the highest millable cane yield and ethanol yield and thereby maximum economic returns, sweet sorghum hybrid, viz. CSH 22SS should be grown using SSI as the method of establishment.
  • ThesisItemOpen Access
    Nutrient and weed management in rice- rice cropping Sequence
    (2021) Kumari, Gayatri; Deka, N.C.
    A field experiment entitled “Nutrient and weed management in rice-rice crop sequence” was conducted in ICR Farm of Assam Agricultural University, Jorhat, with autumn and winter rice varieties, Luit and Ranjit, grown in sequence for two years, 2018 and 2019. The investigation, laid out in randomized block design (factorial) with three replications, aimed to study the impact of nutrient and weed management on growth and yield attributes of rice, weed dynamics and changes in soil microbiota. The treatment consisted of four Nutrient managements viz. T1-100% N-P2O5-K2O through inorganic fertilizers (recommended dose of 40-20-20 kg/ha)), T2-75% N through inorganic + 25% N through FYM (P2O5 & K2O recommended doses), T3-75% N through inorganic + 25% N through vermicompost (P2O5 & K2O recommended doses) and T4- 75% N through inorganic + 25% N through Crop residues and bio-fertilizer (P2O5 & K2O recommended doses); three weed management treatments viz: W1-Pyrazosulfuron @ 25g/ha + 2,4-D @ 0.5kg/ha in both autumn and winter rice,W2-Pyrazosulfuron @ 25g/ha + 2,4-D @ 0.5kg/ha in autumn rice rotated with Pretilachlor @ 0.75 kg/ha + 2,4-D @ 0.5kg/ha in winter rice and W3-Pyrazosulfuron @ 25g/ha + 2,4 –D @ 0.5kg/ha in autumn rice and only Pretilachlor @0.750kg/ha in winter rice; and two controls viz: C0- Absolute control and C1- Farmer’s practice [(0.750 kg/ha pretilachlor + N-P2O5-K2O (20-10-10 kg/ha)]. Soil of the experiment site was sandy loam in texture, slightly acidic (pH-5.6) in reaction, medium in organic carbon (0.65%), available N (222.63 kg/ha), available P2O5 (21.18) and available K2O (127.71 kg/ha). The results of the two years of experiment indicated that among the nutrient management treatments, significantly higher growth attributes, yield attributes, N-P2O5-K2O content and NPK uptake by rice was observed with treatment T3 (75% N through inorganic + 25% N through vermicompost) and the lowest was observed lowest in treatment T1 (100% N-P-K through inorganic fertilizers) in both the years of autumn and winter rice. Two years of pooled data showed that yield was significantly highest in treatment combination of T3W2 (75% N through inorganic+ 25% N through vermicompost along with Pyrazosulfuron @ 25g/ha + 2, 4-D @ 0.5kg/ha in autumn rice rotated with Pretilachlor @ 0.750 kg/ha + 2,4-D @ 0.5kg/ha in winter rice) in both the years for autumn (3627 kg/ha and 3637.44 kg/ha respectively) and winter rice (3770.7 kg/ha and 3735.2 kg/ha respectively). Significantly lowest weed fresh weight and dry weight, weed density, weed frequency, and relative dry weed weights, with respect to grasses,sedges and broad leaved weeds were observed in treatment T4 (75% N through inorganic + 25% N through crop residues and bio-fertilizer) in both the years of autumn and winter rice. Among the weed management treatments, W2 (Pyrazosulfuron @ 25g/ha + 2,4-D @ 0.5kg/ha in autumn rice rotated with Pretilachlor @ 0.75 kg/ha + 2,4-D @ 0.5kg/ha in winter rice) was observed with the lowest weed fresh weight and dry weight, weed density, weed frequency, and relative dry weed weights, with respect to grasses, sedges and broad leaved weeds. The results pertaining to metagenomic study of bacterial and fungal population suggested that there were considerable changes in the population for both the microbes from 0 DAT to physiological maturity due to the nutrient and weed management treatments. The observed changes as indicated by their Operational taxonomic units (OTUs) percentage, Alpha diversity and Beta diversity indices are also indicative of having their direct or indirect impact on soil fertility status. In the present investigation, highest value in terms of agronomic efficiency, nitrogen use efficiency, energy output, energy productivity ratio, energy efficiency index and was highest in the treatment combination of T3W2 (75% N through inorganic+ 25% N through vermicompost along with Pyrazosulfuron @ 25g/ha + 2, 4-D @ 0.5kg/ha in autumn rice rotated with Pretilachlor @ 0.750 kg/ha + 2,4-D @ 0.5kg/ha in winter rice) in both the years for autumn and winter rice. Also, the same treatment combination, i.e., T3W2 (75% N through inorganic+ 25% N through vermicompost along with Pyrazosulfuron @ 25g/ha + 2, 4-D @ 0.5kg/ha in autumn rice rotated with Pretilachlor @ 0.750 kg/ha + 2,4-D @ 0.5kg/ha in winter rice) showed the highest net return for autumn rice (Rs.42412.99 and Rs. 40972.99 respectively) as well as winter rice (Rs. 59864 and Rs. 58833.9 respectively) of both the years. B: C ratio was also observed to be highest in treatment combination of T3W2 (75% N through inorganic+ 25% N through vermicompost along with Pyrazosulfuron @ 25g/ha + 2, 4-D @ 0.5kg/ha in autumn rice rotated with Pretilachlor @ 0.750 kg/ha + 2,4-D @ 0.5kg/ha in winter rice) in both the years of autumn (3.22 and 3.12 respectively) and winter rice(4.63 and 4.56 respectively). Thus, from the above observations, it can be incurred that application of 75% N through inorganic+ 25% N through vermicompost along with Pyrazosulfuron @ 25g/ha + 2, 4-D @ 0.5kg/ha rotated with Pretilachlor @ 0.750 kg/ha + 2,4-D @ 0.5kg/ha, can be considered as the best practice of nutrient and weed management for rice-rice cropping sequence in the prevailing conditions of Assam. It is, however, needed to be practiced in multi- locational trials in order to obtain a much better understanding, conclusion and feasibility before recommending to the farmers. Further investigations to study the impact of the inorganic herbicides and nutrients on the soil microbial population is also required so that they are, accordingly, recommended to the farmers, with the long term motive of maintaining sustainability of soil in addition to focusing upon increasing productivity and meeting the population demands.
  • ThesisItemOpen Access
    INTEGRATED NUTRIENT MANAGEMENT IN YELLOW SARSON - GREENGRAM CROPPING SYSTEM UNDER RAINFED CONDITION
    (2016) Gogoi, Bebi; Ojha, N. J.
    A field experiment entitled “Integrated nutrient management in yellow sarson - greengram cropping system under rainfed condition” was carried out at the Instructional-cum-Research farm of Assam Agricultural University, Jorhat during two consecutive rabi (Oct-Feb) followed by summer (Feb-May) seasons of the year 2017- 2018 and 2018-2019. The experiment was laid out in randomized block design for first crop and split plot design for second crop with three replications. The eight INM practices viz., 100% RDF (60-30-30 kg/ha N-P2O5-K2O) (Y1), 100% RDF + biofertilizer consortium (Y2), 75% RDF + 25% N through vermicompost (Y3), 75% RDF + 25% N through vermicompost + biofertilizer consortium (Y4), 50% RDF + 50% N through vermicompost (Y5), 50% RDF + 50% N through vermicompost + biofertilizer consortium (Y6), 25% RDF + 75% N through vermicompost (Y7) and 25% RDF + 75% N through vermicompost + biofertilizer consortium (Y8) were applied to yellow sarson crop. In greengram crop the residual effect of the treatments applied to yellow sarson were allotted in main plots and two different integrated nutrient management practices viz., 100% RDF + biofertilizer consortium (G1) and 50% RDF + biofertilizer consortium (G2) in the sub plots. The soil of the experimental site was sandy loam in texture, acidic in reaction (pH 5.40 and 5.56), medium in organic carbon (0.69 and 0.72%), available N (274.86 and 290.75 kg/ha), available K2O (138.16 and 140.89 kg/ha) and low in available P2O5 (17.90 and 20.30 kg/ha) in the year 2017-18 and 2018-19, respectively. Experimental findings revealed that application of 75% RDF + 25% N through vermicompost + biofertilizer consortium (Y4) resulted in significantly higher growth as well as yield attributing characters like plant height, number of branches per plant, dry matter accumulation, crop growth rate, relative growth rate, number of siliquae per plant, length of siliqua, number of seeds per siliqua in both the years. The highest seed yield of 998.34, 1026.22 and 1012.28 kg/ha, stover yield of 2393.97, 2420.65 and 2407.31 kg/ha during 2017-18, 2018-19 and in pooled analysis, respectively, were recorded with treatment having 75% RDF + 25% N through vermicompost + biofertilizer consortium (Y4). The seed oil content of 36.40 and 36.97% and seed protein content of 13.27 and 13.44% were also recorded in Y4 in 1st and 2nd year, respectively. Similar effects of this treatment were also observed in respect of N, P and K content and uptake by both seed and stover. However, soil microbial population, microbial biomass carbon, phosphomonoesterase activity and fluorescein di-acetate hydrolase activity after harvest of yellow sarson were significantly higher in treatment having 25% RDF + 75% N through vermicompost + biofertilizer consortium (Y8). The crop recorded the highest gross return (` 56105 in 2017-18 and ` 57652 in 2018-19), net return (` 35407 during 2017-18 and ` 36954 during 2018-19) and benefit-cost ratio (2.71 during 2017-18 and 2.79 during 2018-19) with the treatment containing 75% RDF + 25% N through vermicompost + biofertilizer consortium (Y4). 7 In case of greengram, residual effect of 25% RDF + 75% N through vermicompost + biofertilizer consortium (Y8) resulted in significantly higher growth as well as yield attributing characters like plant height, number of branches per plant, dry matter accumulation, crop growth rate, number of pods per plant and number of seeds per pod in both the years. The effect of these was reflected in higher seed yield (849.56, 806.56 and 828.06 kg/ha in the year 2018, 2019 and in pooled analysis, respectively) and stover yield (2012.68, 1935.58 and 1974.13 kg/ha in 2018, 2019 and in pooled analysis, respectively) under the same integrated nutrient management practices. The maximum values of N, P and K uptake by seed and stover, soil microbial population, microbial biomass carbon, phosphomonoesterase activity and fluorescein di-acetate hydrolase activity after harvest of greengram were also observed under this treatment (Y8). However,direct application of 100% RDF + biofertilizer consortium (G1) brought about higher values in growth parameters, yield attributes, yield of seed (804.21, 724.68 and 764.45 kg/ha during 2018, 2019 and in pooled analysis, respectively) and stover yield (1830.89, 1763.80 and 1797.35 kg/ha during 2018, 2019 and in pooled analysis, respectively), protein content in seed (22.39 and 22.26% in 2018 and 2019 respectively), content and uptake of N, P and K by both seed and stover, soil microbial population, microbial biomass carbon, phosphomonoesterase activity and fluorescein diacetate hydrolase activity after harvest of greengram over 50% RDF + biofertilizer consortium (G2). The highest gross return (` 50726 in 2018 and ` 48922 in 2019), net return (` 33611 during 2018 and ` 31807 during 2019) and benefit-cost ratio (2.96 during 2018 and 2.86 during 2019) were observed under treatment Y8G1 containing 100% RDF + biofertilizer consortium (G1) + residue of treatment Y8 (25% RDF + 75% N through vermicompost + biofertilizer consortium). In regards to yellow sarson-greengram cropping system the highest yellow sarson equivalent yield (1678.57 and 1614.02 kg/ha in 2018 and 2019, respectively) were obtained by treatment Y4G1 containing 100% RDF + biofertilizer consortium (G1) + residue of treatment Y4 (75% RDF + 25% N through vermicompost + biofertilizer consortium). The highest gross return (` 93518 in 2017-18 and ` 89981 in 2018-19), net return (` 55705 during 2017-18 and ` 52168 during 2018-19) and benefit-cost ratio (2.47 during 2017-18 and 2.37 during 2018-19) of yellow sarsongreengram cropping system were observed under treatment Y4G1, containing 100% RDF + biofertilizer consortium (G1) + residue of treatment Y4 (75% RDF + 25% N through vermicompost + biofertilizer consortium). The performance of yellow sarsongreengram cropping system was assessed on the basis of yellow sarson equivalent yield, net monetary returns and B-C ratio. The application of 75% RDF + 25% N through vermicompost + biofertilizer consortium to yellow sarson and 100% RDF + biofertilizer consortium to greengram was the most beneficial combination compared to rest of the treatments.
  • ThesisItemOpen Access
    EVALUATION OF PANCHAGAVYA AS ORGANIC INPUT FOR LATE SOWN RAPESEED PRODUCTION
    (AAU, Jorhat, 2021) DAS, NILAKHI; Goswami, Jogesh
    A field experiment entitled “Evaluation of panchagavya as organic input for late sown rapeseed production” was conducted at the organic block of the Instructional-cum-Research (ICR) Farm, Assam Agricultural University, Jorhat during rabi season of the year 2020- 2021 to evaluate the effects of panchagavya on growth, yield and economics of late sown rapeseed as well as their overall impact on soil health. The experiment was laid out in Randomised Block Design with three replications. The experiment consisted of eight treatments viz.,T1: control (no organic input )), T 2 : RDN through vermicompost , T 3 : Vedic panchagavya soil application (3%), T 4 : 1 tonne VC/ha as basal + Vedic panchagavya foliar application (3%), T 5 : e nriched panchagavya soil application (3%), T 6 : e nriched panchagavya foliar application ( 3%), T 7 : Vedic panchagavya basal application (1.5%) + Vedic panchagavya foliar application (1.5%), T 8 : e nriched panchagavya basal application (1.5%)+ enriched panchagavya folia r application ( 1.5%). The soil of the site where experiment was carried out was sandy loam in texture, acidic in reaction. The soil of experimental site was medium in organic carbon (0.48 %), medium in av ailable N, P 2 O 5 and K 2 O (268.86, 21.87 and 172 .82 kg/ha , respectively The crop was sown on 9 December, 2020 and harvested on 19 March, 2021. The crop took average duration of 101 days during experimentation. Experimental findings revealed that different treatments significantly influenced bo th growth and yield attributing characters of late sown rapeseed. Maximum values of growth parameters were recorded in 1tonne VC/ha as basal + Vedic panchagavya FA (3%) treatment (T 4 ). Maximum values of yield parameters were also observed under 1tonne VC/h a as basal + Vedic panchagavya FA (3%) treatment. The highest seed yield (6.89q/ha) and stover yield (20.48 q/ha) were recorded in this treatment (T 4 ). The highest oil yield (258.91 kg/ha) of rapeseed and also increased nutrient content and up take were recorded with application of 1tonne VC/ha as basal + Vedic panchagavya FA (3%) 3%). The better chemical properties of the soil after harvesting was recorded in RDN through VC (T 2 ) treatment but better biological properties viz ., microbial population i.e., bacteria ( 26.12 x 10 7 cfu/g of soil ) and fungi ( 29.89 x 10 4 cfu/g of soil) and dehydrogenase activity (9.48 µg TPF/g/24 hrs were recorded under treatment T 4 The economic study revealed that the highest gross return (Rs. 55120/ha) was observed in 1 tonne VC/ha as basal + Vedic panchagavya foliar application (3%) (T 4 ) treatment. But the maximum net return (Rs. 34020/ha) and B:C ratio (1.90) were recorded in enriched panchagavya foliar application ( (T 6 From t his study, it can be concluded that the Vedic panchagavya @ 3% as foliar application along with 1 ton ne of VC/ha as basa l (T 4 ) under late sown condition was found to be the best among all the treatments in terms of growth and yield attributes as well as yield of the rapeseed var. TS 67 But, foliar application of enriched panchagavya @ 3% (T 6 ) was identified as profitable among all the treatments with the highest B:C ratio o f 1.90.
  • ThesisItemOpen Access
    Effect of tillage and weed control methods on growth and yield of kharif sesamum (Sesamum indicum L.) under upland situation
    (AAU, Jorhat, 2021) Nath, Mrinmoy Jyoti; Bayan, H C.
    A field experiment entitled “Effect of tillage and weed control methods on growth and yield of kharif sesamum (Sesamum indicum L.) under upland situation” was carried out during kharif, 2020 at P.G. Experimental Field, Department of Agronomy, B.N. College of Agriculture, AAU, Biswanath Chariali with the objectives of (i) Assess the effect of tillage and weed control methods on weed population and growth in kharif sesamum (ii) Evaluate the effect of different treatments on growth and yield of kharif sesamum and (iii) Suggest an effective weed control method(s) for kharif sesamum. The experiment was laid out in a split-plot design with two tillage operations (Zero tillage and Conventional tillage) as main plot treatment and six weed control methods viz., manual weeding twice at 20 DAS and 40 DAS; Quizalofop-p-ethyl 5% EC @ 0.05 kg a.i. ha-1 at 20 DAS; Imazethapyr 10% SL @ 0.075 kg a.i. ha-1 at 20 DAS; Quizalofop-p-ethyl 5% EC @ 0.05 kg a.i. ha-1 at 20 DAS + Rotary weeding at 40 DAS; Imazethapyr 10% SL @ 0.075 kg a.i. ha-1 at 20 DAS + Rotary weeding at 40 DAS and unweeded (control) as sub-plot treatment, replicated thrice. The results of the present investigation revealed that, the conventional tillage significantly suppressed weed dry weight at 20 and 40 DAS and resulted in marked increase of weed control efficiency at 40 DAS. Conventional tillage also recorded comparatively lower weed density (at all crop growth stages); lower weed dry weight (60 DAS and at harvest) and higher weed control efficiency (60 DAS and at harvest) over zero tillage. Significantly higher plant dry weight, initial crop growth rate, and capsules plant-1 were recorded under conventional tillage and resulted in significant increased of seed yield (823.58 kg ha-1), stover yield (3118.29 kg ha-1), harvest index (26.58%) and gross return (Rs 52,408 ha-1). However, comparatively higher B:C was recorded in zero tillage over conventional tillage. Weed control methods had significant effect on reducing the weed densityand weed dry weight at all the crop growth stages except at 20 DAS and resulted in increased weed control efficiency. Among the weed control methods, manual weeding twice recorded significantly lowest weed density, weed dry weight and better weed control efficiency over unweeded (control). Weed control methods also had significant effect on crop growth and yield attributing characters of sesamum. Among the weed control methods, manual weeding twice recorded significantly higher seed yield (1263.61 kg ha-1), stover yield (3647.86 kg ha-1), harvest index (30.40%) and B:C (2.67) and unweeded (control) recorded lowest seed yield (454.72 kg ha-1), stover yield (2717.61 kg ha-1) and B:C (1.39) in kharif sesamum. Cultivation of kharif sesamum under conventional tillage and weed suppression by manual weeding twice at 20 and 40 DAS can be judged as the best methods studied on the basis of better weed suppression, crop yield and economic indices.
  • ThesisItemOpen Access
    EFFECT OF SOWING DATES AND SEED PRIMING ON GROWTH AND YIELD OF RAPESEED UNDER RAINFED CONDITION
    (AAU, Jorhat, 2021) Shreera, Hidangmayum; Sarma, Digambar
    A field experiment entitled “Effect of sowing dates and seed priming on growth and yield of rapeseed under rainfed condition” was conducted during rabi, 2020-21 at the PG Experimental Field of the Department of Agronomy, BNCA. The objectives of the experiment were (i) To find out the effect of sowing dates and seed priming on growth parameters of rapeseed and (ii) To study the effect of different treatments on yield and yield attributes of rapeseed. The treatments consisted of 3 levels of dates of sowing viz., 30th October (D1), 15th November (D2) and 1st December (D3) and 5 levels of seed priming methods viz., Farmer’s practice (S0), Water soaked for 10hrs (S1), Potassium chloride (KCl) @ 2% for 10hrs (S2), Sodium chloride (NaCl) @ 1% for 8hrs (S3) and Potassium dihydrogen phosphate (KH2PO4) @ 1% for 10hrs (S4) with three replications. The soil of the experimental site was acidic (pH 4.64), sandy loam in texture, medium in organic carbon content (0.64%), low in available N (232.06 kg ha-1), P2O5 (21.65kg ha-1) and K2O (113.20 kg ha-1) having a bulk density of 1.42 (g cm-3). The results revealed that sowing of the crop at different dates and different seed priming techniques had significant effect on most of the growth and yield attributes viz., emergence percentage, plant height, stem dry weight, leaf dry weight, reproductive dry weight, total dry weight, leaf per plant, leaf area per plant, LAI, CGR, RGR, number of primary branches per plant, total chlorophyll content, plant population, siliqua per plant, seeds per siliqua, seed yield per plant, seed yield, stover yield and HI. There was significant increase in the plant height, dry matter accumulation, no. of leaves, leaf area, LAI, CGR, RGR from 30DAS to harvest. However, dates of sowing did not show any significant effect on RGR at 60DAS. Moreover, both dates of sowing and seed priming did not show any significant effect on test weight. Among the different dates of sowing the crops sown on 15th November recorded the highest seed yield and harvest index (8.93 q ha-1 and 44.03 %respectively) which was statistically superior over the crop sown on 1st December. Similarly, among the seed priming methods the crops primed with KCl 2% for 10hrs showed highest seed yield (9.96 q ha-1) and harvest index (44.49 %). The highest gross return (Rs 40,188 /ha), net return (Rs 20,210 /ha) and B:C ratio (2.01) was recorded from the crop sown on 15th November (D2). Different seed priming methods recorded significantly higher values for KCl @ 2% for 10 hrs priming (S2) with highest gross return (Rs 44,830 /ha), net return (Rs 24,835/ha) and B:C ratio (2.24). Interaction between sowing dates and seed priming showed significant differences in the economic parameters. 15th November sowing with KCl @ 2% for 10 hrs priming (D2S2) resulted in highest gross return (Rs 53,310 /ha), net return (Rs 33,315/ha) and B:C ratio (2.67). From the findings of the present experiment, it can be concluded that sowing of rapeseed on 15th November and seed priming with KCl @ 2% for 10 hrs can be suggested for higher productivity of the crop and better profitability to the farmers.