A field experiment was conducted at the Agronomy Research Farm (kharif 2021 and 2022), College of Agriculture, Central Agricultural University, Imphal (24°81′ N, 93°89′ E; 790 m above MSL), to evaluate the economic performance of aromatic rice cultivars under different weed management practices in the subtropical conditions of Manipur Valley. The experiment followed a split-plot design with three replications, featuring four cultivars- Khamanui Lungra (C1), Chaphemai (C2), Nambew (C3) and Chakhao Poireiton (C4) and five weed management strategies: W1-Manual weeding, W2-Pre emergence application of Pretilachlor 50% EC @ 450g a.i ha-1 followed by post emergence application of Metsulfuron methyl 10% + Chlorimuron ethyl 10% WP @ 4g a.i ha-1, W3-Pre emergence application of Pretilachlor 50% EC @ 450g a.i ha-1 followed by post emergence application of Penoxsulam 2.67% @ 25 g a.i ha-1, W4-Pre emergence application of Pyrazosulfuron Ethyl 10% WP @ 50 g a.i ha-1 followed by post-emergence Penoxsulan 2.67% @ 25g a.i ha-1 and W5-Control. Results revealed that among the cultivars, ‘Chaphemai’ (C2) recorded the highest plant height (196.9 cm), number of tillers per hill (11.3) and leaf area index (5.41), contributing to a superior grain yield of 4.69 t ha-1. The W3 treatment was most effective in suppressing weeds and enhancing growth, yield and profitability, recording the highest grain yield (3.28 t ha-1), net returns (₹1,04,062.87 ha-1) and benefit-cost ratio (3.32). In contrast, the control (W5) registered the lowest yield (20.26 q ha-1), net returns (₹39,785.53 ha-1) and B:C ratio (1.75), highlighting the economic risk of poor weed management in aromatic rice cultivar of Manipur. Economic analysis confirmed that the combination of Chaphemai with Pretilachlor+ Penoxulam (W3) treatment offered the most promising outcome for aromatic rice cultivation in the region, both agronomically and financially.

Background: Agricultural crop diversification is an important stress relieving option for economic growth of the farming community. Integration of pulses in crop rotation helps in sustainability enhancing overall productivity and profitability of the cropping system. Broad bean (Vicia faba L.) is one of the important pulse crop of Manipur grown in the cool season. Methods: The Present investigation was carried out at Central Agricultural University, Imphal during the kharif and rabi season of 2021-22 and 2022-23. The kharif rice experiment was laid out in randomized block design with 8 treatments as main plot replicated three times. During rabi season each main plot treatment was split into three sub plot treatments with three levels of recommended dose of fertilizers to broad bean resulting in twenty four treatment combinations replicated three times in split plot design. Result: Residual effect of 100% RDF + Azolla + Azospirillum + Neem powder (N5) applied to previous kharif rice crop recorded significantly higher yield attributes, seed and stover yields and economic of broad bean. Among the levels of RDF directly applied to rabi broad bean, application of 100% RDF (F2) resulted in higher values of yield attributes, seed and stover yields and economic of broad bean.

Background: Green gram is one of the oldest and third-most significant traditional pulse crop grown in India. Green gram growthand economics are mostly hampered by weeds, however these effects can be reduced by using appropriate weed control techniques. Methods: A field experiment entitled “Growth, yield and nutrient uptake of green gram (Vigna radiata L.) as influenced by weed management practices under medium land situation on manipur” was conducted at Agronomy Research Farm, College of Agriculture, Central Agricultural University, Imphal, Manipur during Kharif season 2023-24. The experiment was consist of Nine treatments in randomized block design (RBD) replicated thrice. Result: The result revealed that T8: hand weeding at 20 and 35 DAS recorded higher growth parameters like plant height, fresh and dry weight of plant, number of nodules plant-1, fresh and dry weight of nodules plant-1 leaf area index (LAI), crop growth rate (CGR), relative growth rate (RGR) and net assimilation rate (NAR) which was statically at par with T4: Oxyflurofen @ 150 g/ha (PE-2DAS) + Hand weeding (35 DAS). While, maximum net return (104373.98) and B: C ratio (2.22) was found under the treatment T4 (Oxyflurofen @ 150 g ha-1 (PE- 2 DAS) + Hand weeding 35 DAS).

Rice paddies are a significant source of greenhouse gases (GHG), especially methane (CH4).As 52

The research was aimed at analyzing the performance of winter potato under different nitrogen rates at the experimental fields of College of Agriculture, Central Agricultural University, Imphal. The variety Kufri Sindhuri was cultivated during the winter seasons of 2017-18 and 2018-19 under three different nitrogen rates- 120 kgha-1 (N1), 100 kgha-1 (N2) and 80 kgha-1 (N3) using drip irrigation. The results indicated that plants fertilized with 120 kgha-1 nitrogen recorded maximum germination percentage (86.17%), plant height (40.47cm), number of shoots plant-1 (4.50), stem girth (0.56cm), crop growth rate (17.96gm-2day-1), relative growth rate (2.75gg-1day-1), weight of tubers per plant (1.04kg) and tuber yield (19.96t/ha) amongst other treatments. Thus, concluding that healthy plants and good yield of potato was obtained when fertilized with 120 kgha-1 of Nitrogen in Imphal.

Rice bean (Vigna umbellata) is one of the under-utilized crops which can become a promising pulse crop. A field experiment was conducted during kharif season of 2020 at Research Farm, College of Agriculture, Central Agricultural University, Imphal, Manipur to study the effect of planting geometry and nutrient management on yield, economics and quality of dwarf rice bean under rainfed condition. The experiment was laid out in Factorial Randomized Block Design (FRBD) and nutrient management which was replicated thrice. The treatments comprised of three planting geometry viz; S1 : 30 cm x 10 cm, S2: 45 cm x 10 cm and S3: 60 cm x 10 cm and four nutrient management practices viz; F0: Seed treatment with molybdenum + phosphate solubilizing bacteria (PSB), F1: 20 kg P2O5/ha + seed treatment with molybdenum+ PSB, F2:40 kg P2O5 /ha + seed treatment with molybdenum+ PSB and F3: 60 kg P2O5 /ha + seed treatment with molybdenum+ PSB. Results indicate that planting geometry at 60 cm × 10 cm and nutrient management at 60 kg P2O5/ha with seed treatment of molybdenum + phosphate solubilizing bacteria (PSB) significantly influenced the yield and quality of dwarf rice bean and gave the maximum economic returns. The highest seed yield (14.65 q/ha) was recorded with spacing S3 which was significantly superior over S1 upto the tune of 8.7% (13.37q/ha). Among the different nutrient management practices, highest seed yield (16.01 q/ha) was recorded from F3 which was found to be at par with F2 (15.70 q/ha) and significantly superior over F1 and F0 (12.71 q/ha and 11.70 q/ha, respectively). The increase in seed yield in F3 and F2 were 26.9% and 25.5%, respectively over control (F0). Among the various planting geometry, the highest gross return (Rs 117240/ha), net return (Rs 71334/ha) and benefit cost ratio (2.54) were recorded from S3 and lowest gross return (Rs 106960/ha), net return (Rs 60304/ha) and benefit cost ratio (2.29) from S1. In respect of nutrient management the maximum gross return (Rs128053/ha), net return (Rs 80877/ha) and benefit cost ratio (2.72) were associated with F3 and lowest from F0 (Rs 93360, Rs 48058 /ha 2.06, respectively). The interaction effect of S3 and F3 gave highest crude protein yield (397.75 kg/ha) which was 48.2 % higher than S1 and F0 (205.92 kg/ha).

Aim: To study the effect of sowing time and integrated nitrogen management on yield and post-harvest soil nutrient status of black glutinous maize (Zea mays L.). Study Design: Factorial randomized block design (FRBD). Place and Duration of Study: Experimental field of College of Agriculture, Central Agricultural University, Imphal, Manipur, pre-kharif season of 2018. Methodology: The treatment consisted of four different integrated nitrogen management practices and three sowing dates. Results: The result revealed that maximum cob length (16.97cm), cob girth (15.71cm), test weight (257g), grain yield (32.9 q/ha) and shelling % (80.31%) was observed in the treatment N3 (RDN- 75% through urea + 25% through FYM) among different integrated nitrogen management practices. The highest yield among different sowing dates was recorded on plants sown on 9th April (28.23 q/ha). The different integrated nitrogen management showed significant difference in residual nutrients and organic carbon in soil. Maximum available nitrogen (275.97 kg/ha), phosphorus (19.21 kg/ha), potassium (210.05 kg/ha) and organic carbon (1.10%) were observed in treatment N4 (RDN- 100% through FYM). Lowest values of nutrients under study were observed in treatment N1 where the crop received only chemical fertilizer.

A pot experiment was conducted with thirty soils of varying characteristics for selecting the most suitable chemical extractant for available sulphur. Rice variety CAU-R1(Tamphaphou) was grown in pots treated with and without sulphur for eight weeks. At harvest dry matter of rice was recorded. The average dry matter yield increased significantly @30 kg ha-1 levels of S application. Sulphur in the soils was extracted with four different extractants. The extractable S of the soils varied considerably with the soils and the extractant used. In term of the efficiency of extraction,the extractants were in the order : 500 ppm Ca(H2PO4)2.H2O > 0.5M NaHCO3 > 0.5M NH4OAc > 0.15% CaCl2. Available sulphur extracted by 0.5M NH4OAc showed the highest correlation with Dry Matter Yield (0.510882**) , Total Plant Uptake (0.548974**), Bray’s % Yield (0.514887**), Bray’s % Uptake (0.70565**).Therefore,0.5M NH4OAc extractant was rated as most promising extractant for assessing S availability for rice in acid soils of Manipur. pH (-0.12481, -0.04153837, 0.15850443, -0.02106*), EC (-0.2696*,-0.08246, -0.21701*,-0.28734*),CEC (-0.27441*, -0.24183*, -0.18531, -0.28287*), sand (-0.00152, -0.0166 , -0.10168, 0.121165), silt (-0.00858 , -0.15039, -0.10699, 0.030722), Ca2+ (-0.1528, -0.1056 , 0.007184 , -0.09847) and Mg2+ (-0.27248*, -0.16614, -0.07896, -0.24056*) had negative correlations with all extractants of S. The positive relationships of almost all extractants of sulphur with clay texture (0.040966, 0.20296*, 0.306651**,-0.0879), organic carbon(0.096396, 0.32224**, 0.201351*, -0.09377), nitrogen (0.036851, 0.203472*, 0.24579*, -0.06179), phosphorus (0.301882**, 0.268273719*, 0.322386047**, 0.209681*) and potassium (0.023932, -0.00667852, -0.04825616 , 0.079524) were observed.

A field experiment was carried out at the College of Agriculture, CAU, Imphal, Manipur during the rabi season of 2019-2020. The experiment was laid out in Randomized Block Design with three replications. There were nine treatments which consisted of different sole and combined application of phosphorus, organic manure and Biophos. The result indicated that application of 75% RDP + FYM @ 5 t/ha + Biophos @ 20 ml/kg seed (T4) recorded significantly higher growth parameters over all the other treatments in terms of plant height (28.17 cm), number of branches per plant (8.23), fresh and dry weight of plant (14.60 g and 6.26 g) and also the yield attributes such as number of pods per plant (164.30), number of seeds per pod (2.57) besides higher seed and stover yield (15.50 and 19.03 q/ha) as well as crude protein content (23.28%) and crude protein yield (367.83 kg/ha) of the crop. The treatment T4 was closely followed by T5 (75% RDP + Vermicompost @ 2 t/ha + Biophos @ 20 ml/kg seed) in respect of seed yield and crude protein content.

A field experiment entitled "Effect of Nitrogen and Molybdenum on Crop growth, yield and soil properties of Pea (Pisum sativum L.) in acid soil" was carried out at the research field of Central Agricultural University, Iroishemba, Imphal, Manipur during the Rabi season of 2019 - 2020. The experiment was laid out in Factorial Randomized Block Design (FRBD) with 3 replications. There were 16 treatments combinations in the experiment consisting of 4 levels of nitrogen (N1, N2, N3, N4) viz., 0, 10, 20, 30 kg/ha and 4 levels of molybdenum (M1, M2, M3, M4) viz., 0, 0.4, 0.8, 1.2 kg/ha. The results revealed that application of nitrogen level N3 (20 kg N/ha) and molybdenum level M3 (0.8 kg Mo/ha) significantly increased crop growth, yield parameters, nutrient content in plants and in post- harvest soil.

A field experiment was conducted during the rabi season of 2019-2020 to study the "Influence of Integrated Phosphorus Management on the Growth, Yield and Quality of Lentil (Lens culinaris L. Medik.)". The soil of the experimental field was clay in texture with pH of 5.54 and organic carbon content of 0.8%. The minimum and maximum temperatures recorded during the period under review were 10.3 and 24.5oC with a total rainfall of 246.4 mm and average sunshine of 8.6 hours respectively. The experiment was laid out in Randomized Block Design with three replications. There were nine treatments which consisted of different sole and combined application of phosphorus, organic manure and Biophos. It was observed that application of 75% RDP + FYM @ 5 t/ha + Biophos @ 20 ml/kg seed (T4) proved significantly superior to all the treatments in terms of all parameters viz nodule number (61.0), fresh and dry weight of nodule (36.0 and 26.0 mg), number of pods per plant (164.30), number of seeds per pod (2.57), seed and stover yield (15.50 and 19.03 q/ha). The highest gross income (Rs. 118500 /ha) and net return (Rs. 82510 /ha) were also associated with the treatment T4. However, T4 and T1 exhibited similar B:C ratio of 3.29. The treatment T4 showed significant enhancement of post-harvest soil nutrient status.

Central Agricultural University, Imphal, Manipur, to study the effect of crop establishment methods and nitrogen management on growth and yield of rice (Oryza sativa L.).Rice cultivar CAU-R3 was grown with twelve treatment and laid out in split plot design, keeping crop establishment methods viz.C1-system of rice intensification (SRI), C2-integrated crop management (ICM) and C3-conventional as main plot with four nitrogen management viz.N1-100% recommended dose of nitrogen (RDN) through urea, N2-100% RDN through farm yard manure (FYM), N3-75% RDN through urea + 25% RDN through FYM and N4-50% RDN through urea + 50% RDN through FYM in sub-plot, replicated thrice.Studies from pooled data found out that C1 contributed the highest value of growth parameter and yield attribute as compared to C2 and C3.Among the nitrogen management N3 produces the highest growth parameter at all the stages of crop except at 30 days after transplanting than other three nitrogen management as well as highest value of yield attribute and yield.However, rice grown under ICM produces significantly higher yield than conventional method but at par with SRI.

A field experiment was conducted during pre-kharif season of 2016 and 2017 at Research Farm, College of Agriculture, Central Agricultural University, Imphal, Manipur, to study the effect of crop establishment methods and nitrogen management practices on physiological characteristic of rice. The experiment was laid out in split plot design with three crop establishment methods in main plot and four nitrogen management practices assigned to sub plot with three replication. Among the crop establishment methods SRI method has highest dry matter production hill-1, RGR while conventional method has highest LAI and ICM recorded the highest CGR and NAR. Treatment N3-75% RDN through urea + 25% RDN through FYM produces the highest value in all the physiological character and yield than the remaining three nitrogen management practices. However, due to more dry matter production per meter and crop growth rate ICM contributed the highest yield among the crop establishment methods.

A field experiment was conducted during the kharif season of 2016 and 2017 in the Research farm of College of Agriculture, Central Agricultural University, Imphal in order to study the effect of different weed and nutrient management practices on the growth and yield of kharif rice. The experiment was laid out in factorial randomized design (FRBD) replicated thrice. The treatments comprised of five levels of weed management practices and three levels of nutrient management practices. The pooled data revealed that among the weed management practices, application of Pyrazosulfuron ethyl (PE) + Hand weeding (HW) at 40 DAS (W2) gave the highest plant growth attributes like plant height, number of tillers per m2, leaf area index at all the growth stages of kharif rice and highest grain yield of 48.34 q ha-1 and straw yield of 68.15 q ha-1 but it was significantly at par with Pyrazosulfuron ethyl (PE) + Mechanical weeding (MW) at 40 DAS (W3). Among the nutrient management practices, highest grain yield of 43.17 q ha-1 was obtained with the application of 50% RDF+ 6t FYM (N1) followed by the application of 50% RDF+ Azolla (dual crop)@10t/ha + 3t FYM (N2). The interaction between the different weed and nutrient management practices had no significant effect on the growth attributes and yield of kharif rice.

A pot experiment was conducted during 2018-2019 with thirty number of soil samples having different soil characteristics for evaluating the suitability of extractants in soils of Bishnupur distric taking cauliflower as a test crop. Five different extractants such as hot 0.01 calcium chloride, hot water, Mehlich-3, 0.1M salicylic acid and 1.0M of ammonium acetate were used for extracting the soil boron. In terms of efficiency of boron extraction, the extractants followed the order in decreasing trend as Mehlich-3 (M3) Eƒ hot 0.01M Calcium Chloride (HCC) Eƒ hot water (HW) Eƒ0.1M salicylic acid (SA) Eƒ 1.0M ammonium acetate (AA). Among the extractants, hot 0.01M Calcium Chloride recorded the highest correlation with Bray’s percent yield, dry matter yield, B concentration at control and B uptake at control.

Vertical distribution of DTPA-extractable micronutrient cations (Fe, Cu, Mn and Zn) and its correlation with several physico-chemical properties of soils in fifteen orange orchards of Tamenglong district, Manipur was studied.Most of the upper soil layer had higher DTPA-extractable micronutrient cations (Fe, Cu, Mn and Zn) content than the lower horizons.In the profiles, the value of DTPA-extractable micronutrients (Fe, Cu, Mn and Zn) ranged from 18.62 to 45.12 mg kg -1 , 0.12 to 1.26 mg kg -1 , 3.42 to 44.33 mg kg -1 and 0.16 to 1.36 mg kg -1 , respectively.The DTPA-extractable Fe and Mn were found to be sufficiently available in all the profiles whereas, Cu was found adequate in most of the surface horizon (0 -20cm) in most of the soil samples.However, Zn deficiency occurred in 55.56 % of the soil sample.Multiple regression analysis showed that the DTPAextractable micronutrient cations (Fe, Cu, Mn and Zn) content in the soils were influenced by pH, OC, EC, Mg, silt, K and clay to the degree of 50.1, 25.7 and 60.5 % in the surface horizon but their influenced were significant only by soil OC and silt.

A field experiment was conducted during the pre-kharif season of 2018 at experimental field of College of Agriculture, Central Agricultural University, Imphal, Manipur to study the influence of sowing time and integrated nitrogen management on growth and yield of local glutinous maize (Zea mays L.). The experiment was laid out in factorial randomized block design (FRBD) with 12 treatments and 3 replications. The treatment consisted of four different integrated nitrogen management practices and three sowing dates. The result revealed that maximum plant height, plant fresh weight, number of leaves and LAI were recorded with the application of RDN- 75% through urea + 25% through FYM (N3) for the crop sown on 9th April (S3). Similarly maximum number of cobs per plant, number of grain rows per cob, cob length, number of grains per cob and test weight of maize was observed in the treatment N3S3. The maximum grain and stover yield were obtained with the application of RDN- 75% through urea + 25% through FYM and the crop sown on 9th April. It can be concluded that the local glutinous maize (Zea mays L.) responded well to the integrated nitrogen management for the crop sown on 9th April (N3S3) as expressed in growth and yield.