A study was undertaken to evaluate the effects of integrated use of some organic manures and chemical fertilizers on soil fertility and productivity in plant and the subsequent ratoon crops of sugarcane. The manures included press mud, farmyard manure (FYM) and green manure (Crotalaria juncea) and the fertilizers were urea, TSP, MOP, gypsum and zinc sulphate. Application of organic manure in combination with chemical fertilizer increased absorption of N, P and K in cane leaf tissues both in the plant and ratoon crop as compared with chemical fertilizer alone. This led to higher cane and sugar yield of both crops. The maximum cane yield of 108.4 t ha^− 1 and sugar yield of 9.47 t ha^− 1 for the plant crop, and 96.8 t ha^− 1 cane and 9.18 t ha^− 1 sugar yields for the second crop (ratoon) were recorded where FYM at 15 t ha^− 1 accompanied with chemical fertilizer (N₁₇₈P₅₃K₅₄S₂₆Zn_2.6kg ha^− 1) were applied. The organic carbon, total N, and available P, K & S contents of soils increased slightly due to incorporation of organic manure. It appeared that 25% reduction of fertilizer application is possible if FYM or press mud at 15 t ha^− 1 is used in plant and ratoon crops of sugarcane.

The Haors in Bangladesh are saucer-shaped, low-lying land depressions that form deep basins; they remain submerged for approximately half of the year, typically from June onwards. This fragile ecosystem spans over 2.0 million hectares in the northeastern region of the country, accounting for roughly 14% of the total areas, where approximately 19.4 million people reside. Factors including floods, flash floods, and low winter temperatures constrain agricultural productivity in the haor areas. It is a great challenge to change the haor areas from less productive to more productive land. This is a comprehensive analysis of the biophysical and socioeconomic characteristics of haors which also highlights the constraints and opportunities in agricultural production. It explores strategies for significantly increasing crop, livestock, and fish production within the haor ecosystem, in alignment with government policies. Some of the proposed agricultural development strategies for the haor areas include the development of short-duration, cold-tolerant crop varieties, such as Boro rice, utilizing relatively flood-free elevated lands and homesteads for vegetable production and promoting agricultural mechanization, livestock rearing, fisheries, and agribusiness development. The recommendations presented in this paper focus on enhancing crop yields, increasing cropping intensity, and boosting livestock and fish production; ultimately, they contribute to food security, poverty reduction, and improved livelihoods for the inhabitants of the haor areas.

Silicon (Si), applied as calcium silicate (Ca-silicate), was evaluated for effects on yield; yield-contributing parameters in sugarcane, such as chlorophyll content, gas exchange characteristics, moisture content, and leaf nutrient concentrations; and soil fertility in the greenhouse in two different soil types. Seven levels of Si (0 20, 40, 60, 80, 120, and 150 g pot^–1) were tested by applying them with traditional fertilizers. Gas exchange characteristics such as photosynthesis, transpiration, and stomatal conductance were significantly greater with the plants fertilized with silicate over unamended control for both soils. Silicate fertilization increased chlorophyll and moisture contents in the top visible dewlap (TVD) leaf tissues, but results were not significantly better in both soils when compared with unamended control. In our 12-month study, we found that the Si content reached up to 2.64% and 1.86% per dry mass in TVD leaf tissues when amended with Ca-silicate fertilizer in soils 1 and 2, respectively. Results showed that as compared to unamended control, Si-amended treatments significantly increased maximum dry matter and cane yield by 77% and 66% in soil 1 and 41% and 15% in soil 2, respectively. With increasing silicate application, iron, copper, zinc, and manganese contents significantly decreased in leaf tissues and soil contents in both soils. Soil pH, Si contents, available sulfur, exchangeable Ca and magnesium, and cation exchange capacity were increased significantly more or less, whereas aluminum contents of soil decreased dramatically in both soils when amended with Ca-silicate. Our results indicate that different soil fertility status and rates of Si application are important factors influencing the yield, growth parameters, chlorophyll, and nutrient contents of sugarcane leaf as well as soil properties.

A field experiment was conducted at Bangladesh Sugarcrop Research Institute, Ishurdi, Pabna, Bangladesh to examine the effects of enriched compost with chemical fertilizers on soil fertility and productivity of sugarcane. The experiment was laid out in Randomized Complete Block Design (RCBD) with 16 treatments comprising four levels of inorganic fertilizers (100%, 75%, 50% and 0%) and four levels of pressmud (enriched by Trichoderma harzianum @ 7.5 t ha-1, T. viride @ 7.5 t ha-1, untreated raw pressmud @ 10 t ha-1 and control). It was observed that germination (90.34%), total chlorophyll content (2.58 mg g-1), leaf area index (5.00), dry matter (3.41 kg m-2), tiller (137.94 × 000 ha-1), millable cane stalk (99.15 × 000 ha-1) and yield (111.32 t ha-1) were found maximum in 100% recommended fertilizer (N150 P50 K90 S35 and Zn4 kg ha-1) with enriched pressmud which was statistically identical in comparison with 75% and 50% of recommended chemical fertilizers with enriched pressmud. The N (1.47%), K (1.24%) and S (0.17%) contents of leaf tissues were slightly increased with chemical fertilizers + enriched pressmud compared to chemical fertilizer alone. Soil Organic C, total N, P, K and S were higher with pressmud application compared to non pressmud application. Microbial enrichment of pressmud with Trichoderma sp. could save 2.5 t ha-1 of pressmud and 25% of recommended fertilizers. It can be concluded that enriched pressmud is more effective than raw pressmud in increasing sugarcane yield and maintain soil fertility in High Ganges River Floodplain soils.SAARC J. Agri., 13(2): 183-197 (2015)

The conception of critical limit (CL) of a nutrient element distinguishes its deficiency from sufficiency, which could advise fertilizer application. A pot culture experiment was conducted during Rabi season (2019–2020) to study the CL of sulphur (S) in soil and plant. A total of 20 soil samples collected from intensive cropping areas of three agroecological zones (AEZs) of Bangladesh were used in the experiment. The 0.15% CaCl₂ extractable S (expressed as available S) contents of the test soils ranged from 6.84 mg/kg to 38 mg/kg. Wheat (Triticum aestivum L.) cv. BARI gom 30 and mustard (Brassica napus L.) cv. BINA sorisha 9 were used as test crops in this study. There were two rates of S application to soil-0 and 15 mg/kg for wheat and 0 and 18 mg/kg for mustard from gypsum (CaSO₄.2H₂O). Each S treatment was replicated thrice. Dry matter yield, S content and S uptake by the crops increased with added S. For mustard, the CL of soil S was estimated to be 14 mg/kg by graphical procedure and 11 mg/kg in statistical method while plant tissue concentration showed the CL of 0.35% in both methods. The CL of soil S for wheat was found to be 14 mg/kg and 11 mg/kg in graphical and statistical methods, respectively, and the CL of plant tissue concentration was recorded as 0.14%, in both methods. It is expected that mustard and wheat crops would respond to S fertilization in soils containing S at or below the CL. The results would be useful for predicting crop (wheat and mustard) response to S fertilizer and developing efficient S fertilizer management to promote sustainable crop production.