Soil carbon (C) mineralization was studied in an incubation experiment comprised of two factors having six organic materials and three nitrogen (N) rates. Cow dung (CD), rice straw (RS), wood ash (WA), cow dung biochar (CB), rice straw biochar (RB) and wood biochar (WB) considering 2.5 g C kg−1 soil along with three levels of N, i.e., 0, 0.05 and 0.10 g N kg−1 soil were mixed with 400 g of soil used in each pot. The pots were placed for 0, 30, 60, 90, 120, 150 and 180 days of incubation, and soils were collected after each incubation and analyzed for C and N. Irrespective of treatment factors, C decreased in an irregular fashion until 180 days of incubation. From the initial level of 1.91%, C contents decreased to 1.08, 1.10, 1.06, 1.23, 1.17 and 1.12% in soil mixed with CD, RS, WA, CB, RB and WB, respectively, and to 1.28, 1.11 and 0.99% in 0, 0.05 and 0.10 g N kg−1 soil, respectively, at 180 days of incubation. The mineralization followed the order of WA > CD > RS > WB > RB > CB. Biochars could supply stable C in soil, while N enhances mineralization; optimization of N is therefore essential to ensure soil C accretion.

Integrated Nutrient Management (INM) is a novel strategy to achieve sustainable crop production in degraded soils through judicious and balanced plant nutrients utilization. Sole application of chemical fertilizers in crop production causes soil and environmental pollution. The present study was designed to assess the effects of application of organic manures conjointly with chemical fertilizers on growth and yield of okra in acid soil. The experiment was consisted of four treatments viz. T0 [Control], T1 [Recommended dose of chemical fertilizers (RDF)], T2 [Dolomite (D) @ 1t ha-1 + RDF], T3 [Poultry manure (PM) @ 3t ha-1 + RDF], T3 [Cow dung (CD) @ 5t ha-1 + RDF] with six replications in a randomized complete block design. The results indicated that the use of PM with RDF showed better performance in the growth and yield attributes of okra. Compared with others plots, the highest plant height (114.10 cm), fresh weight plant-1 (591.58 g) and dry weight plant-1 (86.73 g) were observed in the PM-treated plot. Similarly, the highest number of fruits plant-1 (20.33) and fruit yield (13.58 t ha-1) were also found in PM-treated plants. Therefore, under acidic soil conditions, organic and inorganic fertilization may have a significant positive impact on the growth and yield of Okra.

Background: A field experiment was conducted during November, 2018 to April, 2019 to evaluate the response of maize to irrigation and nitrogenous fertilizer in shallow red brown terrace soil of Madhupur Tract under AEZ-28 in Bangladesh. Methods: The irrigation was provided as factor A at four distinct rates (irrigation at 20%, 40%, 60% and 80% available water) and nitrogenous fertilizer as factor B at three dosages (75%, 100% and 125% of recommended dose) when each factor was repeated three times. Data relevant to soil and plant parameters were analyzed for variance (ANOVA) using Statistix 10. Result: The yield and yield contributing characters of maize responded significantly to varying degrees of irrigation and N fertilizer, with the treatment I4N2 having the highest cob per plant (1.17), cob yield (16.89 t ha-1), grain yield (9.19 t ha-1), dry matter yield (10.15 t ha-1) and the treatment I3N3 provided statistically identical results as I4N2. The treatment I4N2 also resulted in maximum content of grain N (0.87%), P (0.20%) and K (0.26%). The treatment, irrigation at 80% available water with application of 100% N on recommended dose (I4N2) appeared as the most suitable package for maize cultivation in the stated region.

Soil acidity is considered as one of the limiting factors in agricultural production because it affects plant growth and development by reducing the availability of essential nutrients. Therefore, a field trial was carried out at the experimental field of Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur, Bangladesh from September 2021 to January 2022 to evaluate the effect of various organic and inorganic fertilizers on the growth, yield, and nutritional quality of cauliflower. The experiment was carried out in randomized complete block design with seven treatments viz. Control, Recommended dose of chemical fertilizers (RDF), Poultry Manure (PM) (3 t ha-1) + RDF, Vermicompost (VC) (3 t ha-1) + RDF, Cowdung (CD) (5 t ha-1) + RDF, Rice Husk Biochar (1 t ha-1) + RDF and Household waste compost (3t ha-1) + RDF with three replications. Among different treatments, the highest value for plant height (49.25 cm), number of leaves plant-1 (21.50), curd circumference (39.87cm), curd diameter (18.07 cm), marketable curd weight (777.57g plant-1), marketable curd yield (32.41 t ha-1), N, K, S content (1.92%, 1.87% and 0.33 % respectively) and K and S uptake ( 79.57 kg ha-1 and 13.92 kg ha-1) were recorded from the Household waste compost (3t ha-1) + RDF whose effect was statistically similar to the treatment Poultry Manure (PM) (3 t ha-1) + RDF. The maximum value for curd height (11.10 cm), N uptake (81.81 kg ha-1) and P content and uptake (0.32% and 13.97 kg ha-1 respectively) were recorded from poultry manure along with RDF. Whereas, the minimum value for all growth parameters, yield attributes, nutrient content and uptake were observed from unfertilized control. Therefore, integrated application of organic manures with synthetic chemical fertilizers can be practiced for attaining higher yield and better-quality curds compare to the sole application of inorganic fertilizers in acid soils of Bangladesh.