Productivity, water use efficiency and soil properties of sugarcane as influenced by trash mulching and irrigation regimes under different planting systems in sandy loam soils

IntroductionIn the era of climate change, sugarcane used to face a problem associated with water shortage due to erratic rainfall patterns and lowered water tables. Improved water use efficiency using innovative crop management strategy is needed for sustainable sugarcane production. Trash mulching with different irrigation regimes can effectively modify the plant's hydrothermal micro-environment for increasing cane yield and water productivity.MethodsKeeping this in the background, a field experiment was conducted at Sugarcane Research Institute, RPCAU, Pusa, India, from 2016–17 to 2018–19 to investigate the effects of trash mulching and irrigation regimes on sugarcane productivity, water use efficiency (WUE) and soil properties in different planting systems. The field experiment comprised 12 treatments including four planting methods viz. conventional flat planting (CF; 75 cm row spacing) with trash mulching (6 t ha−1), CF planting (75 cm row spacing) without trash mulching (6 t ha−1), paired row trench (PT) planting (30: 120 cm row spacing) with trash mulching (6 t ha−1), PT planting (30: 120 cm row spacing) without trash mulching (6 t ha−1) and three irrigation schedules consisted of irrigation water (IW); cumulative pan evaporation (CPE) ratio of 0.60, 0.80, and 1.00 was laid out in strip plot design with three replications.Results and discussionThe cane yield (103.5 t ha−1) was found significantly higher in PT planting with trash mulching over the CF planting method with or without mulching. Concerning irrigation regimes using the IW/CPE ratio, it was found that the IW/CPE of 0.6 resulted in 16.9, 13.3% higher water-use efficiency, and 37.1, 40.7% higher water productivity over those under IW/CPE of 0.8, and 1.00, respectively. Furthermore, soil parameters like soil microbial biomass carbon (SMBC) and dehydrogenase activity were increased by 12.5, and 17.5 % due to trash mulching with trench planting as compared to those under conventional flat planting without mulching. The results suggest that planting sugarcane in paired rows and irrigation scheduling at 1.00 IW/CPE with the adoption of trash mulching practices is effective for increasing profitability by way of higher sugarcane productivity and water productivity and also in sustaining soil health

Long-Term Conservation Tillage and Precision Nutrient Management in Maize–Wheat Cropping System: Effect on Soil Properties, Crop Production, and Economics

Intensive tillage coupled with imbalanced nutrient management in maize–wheat systems in low-carbon calcareous soils often results in poor productivity vis-à-vis degradation in soil health. Conservation tillage viz. permanent bed planting (PB) and zero tillage (ZT)/direct seeding with residue retention coupled with precision nutrient management might improve soil properties and yield of crops. Concerning this, a long-term experiment was conducted from 2014–2015 to 2020–2021 with a maize–wheat cropping system at TCA, Dholi farm of RPCAU, Pusa. Treatments consisted of three main plots of different tillage practices, viz. PB, ZT, and conventional tillage (CT) and three sub-plots of nutrient management options, viz. farmers’ fertilization practice (FFP), site-specific nutrient management with Nutrient Expert® (NE) software, and GreenSeeker (GS) based nitrogen-management. From this study, it was observed that both the PB and ZT resulted in about 31–33% and 43–45% improvement in SOC and water-soluble aggregates (WSA), respectively, comparing them under CT. These two conservation tillage practices also improved the other soil bio-chemical properties. Better soil properties under PB and ZT helped in the improvement of system yield by about 13–18% comparing yield under CT. Moreover, both these tillage practices showed an additional net return of USD 330–USD 400 over CT. PB was found a bit better over ZT concerning soil properties, yield, and economics. Comparing nutrient management options, precision nutrition using NE and GS showed significant improvement in the soil bio-chemical parameters, yield, and economics of the cropping system over FFP. SSNM using NE showed slightly better results than GS. Thus, from this long-term study, it can be concluded that the permanent bed system with residue retention and precision nutrition using Nutrient Expert® software are the best options concerning tillage and nutrient management, respectively, for improvement of the soil properties of problematic calcareous soils, thereby, enhancing the yield and economics of the maize–wheat cropping system

Effect of seaweed saps derived from two marine algae Kappaphycus and Gracilaria on growth and yield improvement of blackgram

789-794A field experiment was conducted during the pre-kharif season at Muratipur village, Nadia, West Bengal (Latitude: 22°57′ N, Longitude: 88°20′ E) in two consecutive year of 2012 and 2013 to study the effects of seaweed saps on growth and yield improvement of blackgram in new alluvial soil of West Bengal. Foliar spray was applied twice at different concentrations (0, 2.5, 5.0, 7.5, 10.0 and 15.0% v/v) of seaweed extracts (namely Kappaphycus and Gracilaria) with recommended dose of fertilizer (RDF). Foliar applications of seaweed extract significantly enhanced the growth and yield parameters. Highest grain yield was recorded with the combined applications of 15% Kappaphykus sap and RDF, followed by the combined application of 15% Gracilaria sap and RDF extract resulting in an increase by 51.06% and 47.15% seed yield respectively compared to the control. Maximum stover yield was also achieved with the application of 15% Kappaphykus sap

Effects of varied nutrient regimes on soil health and long-term productivity in a rice–wheat system: insights from a 29-year study in the mollisols of the Himalayan Tarai region

The maintenance of sustainability and quantification of soil health in the rice–wheat system in the Himalayan tarai region is of utmost importance, and a long-term study can properly demonstrate what needs to be done to achieve this. The current study was conducted after the completion of a 29-year crop cycle in the rice–wheat system in 2015 at Pantnagar. Since the beginning of the experiment in 1984, various NPK combinations with or without Zn and farmyard manure (FYM) applications were maintained in a fixed layout along with an absolute control plot without any external nutrition. FYM at 5 mg ha−1 and Zn at 5 kg ha−1 were applied in only rice, and NPK-chemical fertilizers were applied both in rice and wheat. The results revealed that the application of N at 120 kg ha−1 + P at 40 kg ha−1 + K at 40 kg ha−1 + FYM at 5 mg ha−1 + Zn at 5 kg ha−1 (NPK + FYM + Zn) resulted in the maximum attainment of long-term system productivity and the sustainable yield index (SYI), which were 22% higher than those with NPK application. NPK + FYM + Zn and NPK + FYM also improved the soil's overall physical, chemical, and biological parameters. Soil organic carbon, dehydrogenase activity, soil available P and K, phosphate solubilizing bacteria, and actinomycetes were found to be the most important soil quality parameters in Mollisols. From this study, it can be concluded that the application of the recommended NPK along with FYM and Zn can improve soil health and sustain the system productivity of the rice–wheat system in Mollisols of the Himalayan tarai region

An innovative approach to improve oil production and quality of mustard (\u3ci\u3eBrassica juncea\u3c/i\u3e L.) with multi-nutrient-rich polyhalite

Polyhalite popularly known as POLY4 is a multi-nutrient fertiliser containing K, S, Mg, Ca, and micronutrients. POLY4 has a low carbon footprint, is certified for organic agriculture, and has the potential to improve crop productivity and quality attributes Indian mustard which often faces challenges due to imbalanced nutrition supplied in the current fertilisation schedule. The hypothesis of the study was that the multi-nutrient fartiliser POLY4 can ensure balanced nutrition for Indian mustard. Considering this, a field experiment was conducted during the winter seasons of 2017–18 and 2018–19 to evaluate the effect of POLY4 on Indian mustard (Brassica juncea L.) with respect to its yield, quality, and nutrient uptake. POLY4 along with conventional sources of nitrogen (N) and phosphorus (P) was compared to recommended fertilisation practices from conventional sources of N, P, K namely urea, di-ammonium phosphate (DAP), and muriate of potash (KCl). With the application of POLY4, seed yield was significantly improved by about 600 kg ha-1 compared to NP control (no application of K and S) across the two seasons. Compared to recommended practice of NPK, the yield was increased by about 450 kg ha-1 with the application of POLY4. Mustard seed oil and protein percent were also improved with the use of POLY4. POLY4 did not have any adverse effect on the content of anti-nutritional factors and improved the omega-3 fatty acid content of mustard oil. Higher uptakes of macro and micronutrients in the crop were also recorded with POLY4 along with an improved soil nutrient status. From the economic point of view, it was also observed that the application of POLY4 resulted in an increment of net returns of USD 45–60 comparing cultivating mustard with the conventional N, P, K, and S fertilizers only. Therefore, the use of POLY4 as a source of multi-nutrient for balanced nutrition helped to increase the efficiency of applied nutrients which ultimately improved the yield and quality of mustard. This study exhibits the pioneer findings of polyhalite (POLY4) based balanced nutrition in Indian mustard

Labile Soil Organic Matter Pools Are Influenced by 45 Years of Applied Farmyard Manure and Mineral Nitrogen in the Wheat—Pearl Millet Cropping System in the Sub-Tropical Condition

Labile soil organic matter pools (LSOMp) are believed to be the most sensitive indicator of soil quality when it is changed rapidly with varied management practices. In sub-tropical climates, the turnover period of labile pools is quicker than in temperate climates. Organic amendments are of importance in improve the LSOMp for a temperate climate and may be helpful in sub-tropical climates as well. Hence, the status of LSOMp was studied in long term farmyard manure (FYM) amended soils under wheat (Triticum aestivum L.) and pearl millet (Pennisetum glaucum L.) cropping systems in sub-tropical arid conditions. At the same time, we also attempt to determine the impact of mineral nitrogen (N) application in these pools. In this study, dissolved organic matter (DOM), microbial biomass (MB), and light fraction (LF) were isolated in the management practices involving different modes and rates of FYM applications along with the application of nitrogenous fertilizer. C and N contents of the labile pools were analyzed in the soil samples at different periods after FYM applications. Among the different pools, microbial biomass carbon (MBC) and dissolved organic carbon (DOC) were changed significantly with different rates and modes of FYM application and mineral N application. Application of FYM at 15 Mg ha−1 in both the seasons + 120 kg ha−1 mineral N resulted in significantly higher MBC and DOC as compared to all of the other treatments. This treatment also resulted in 13.75% and 5.8% more MBC and DOC, respectively, as compared to the amount of MBC and DOC content in the control plot where FYM and mineral N were not applied. Comparing the labile organic matter pools of 45 years of FYM amendment with initial values, it was found that the dissolved organic carbon, microbial biomass carbon, and light fraction carbon were increased up to the maximum extent of about 600, 1200, and 700 times, respectively. The maximum amount of DOM (562 mg kg−1 of DOC and 70.1 mg kg−1 of DON), MB (999 mg kg−1 of MBC and 158.4 mg kg−1 of MBN), LF (2.61 g kg−1 of LFC and 154.6 g kg−1 of LFN) were found in case of both season applied FYM as compared to either summer or winter applied FYM. Concerning the different rates of FYM application, 15 Mg ha−1 FYM also resulted in a significantly higher amount of DOM, MB, and LF as compared to other FYM rates (i.e., 5 Mg ha−1 and 10 Mg ha−1). Amongst different pools, MB was found to be the most sensitive to management practices in this study. From this study, it was found that the long-term FYM amendment in sub-tropical soil along with mineral N application can improve the LSOMp of the soil. Thus, it can be recommended that the application of FYM at 15 Mg ha−1 in summer and winter with +120 kg ha−1 mineral N can improve SOC and its labile pools in subtropical arid soils. Future studies on LSOMp can be carried out by considering different cropping systems of subtropical climate

Unravelling the Release Kinetics of Exchangeable Magnesium in Acid Soil of Nilgiris

Magnesium deficiency is a pervasive and recurrent factor that significantly restricts crop production, primarily attributable to the low levels of exchangeable magnesium (ex-Mg) present in acidic soil conditions. This deficiency exerts a pronounced negative influence on the sustainability and progress of agricultural development. Hence the current study aspired at modeling the kinetics of Exchangeable Magnesium release from 3 fertilizer sources i.e., Epsom salt (MgSO4·7H2O), Magnesite (MgCO3) and Dolomite [CaMg(CO3)2] in the acidic soil of the Nilgiris district in Tamil Nadu, India. Four mathematical models were verified—Power function, parabolic diffusion, Simple-Elovich, and first-order to explain cumulative Mg2+ release. Power function was noticed to be an outstanding empirical equation finely fitted to the experimental data. The intensity, as well as the modality of the release pattern, was predicted by the numerical parameters. The power function as well as Parabolic Diffusion portrayed the Mg2+ release kinetics best as verified by the maximum correlation coefficients (r2). The parabolic diffusion model also designated the data as suitable, signifying diffusion-controlled exchange. From the derived dissolution rates, it was conceivable to agree Epsom salt (MgSO4·7H2O) from which the release was faster than the other two magnesium sources. In conclusion, these outcomes provided an insight into the temporal dynamics of magnesium availability in acidic soil, highlighting the importance of understanding its release kinetics for sustainable agriculture development. The findings contribute to the broader knowledge of magnesium management strategies, aiding in the development of targeted interventions to alleviate magnesium deficiency and optimize crop productivity in acidic soil environments

Improved Method of Boron Fertilization in Rice (Oryza sativa L.)–Mustard (Brassica juncea L.) Cropping System in Upland Calcareous Soils

Calcareous soils are highly deficient in boron (B) due to having high levels of free CaCO3 and low organic matter. This has become one of the most important deficient micronutrients in Indian soil after zinc (Zn). For various rice (Oryza sativa L.)-based cropping systems, B fertilization is essential for increasing crop productivity and the biofortification of the crop, thus a suitable soil application protocol for B fertilization is required for B-deficient soils. In a six-year experiment, different rates of B application, namely, 0.5, 1.0, 1.5, and 2.0 kg ha−1 y−1, were evaluated to determine the effects of three different modes of B fertilization, i.e., applied only in the first year, applied in alternating years, and applied every year, in a rice (Oryza sativa L.)–Indian mustard (Brassica juncea L.) cropping system. It was observed that the application of B at 1.5 kg ha−1 every year or 2 kg ha−1 in alternate years resulted in the highest yield of rice and mustard, as well as the maximum system productivity of the rice–mustard cropping system. Application of 2 kg ha−1 of B in the initial year showed the maximum B uptake by rice, while application of 1.5–2.0 kg ha−1 of B every year resulted in the maximum B uptake by the mustard crop. Application of B at 2 kg ha−1 in alternate years or 1.5 kg ha−1 every year was the best B-application protocol in B-deficient calcareous soils for ensuring the highest productivity of the rice–mustard cropping system and B availability in the soil

Soil Test Based Fertilizer Application Improves Productivity, Profitability and Nutrient Use Efficiency of Rice (Oryza sativa L.) under Direct Seeded Condition

A field investigation on direct seeded rice (DSR) was carried out in the two consecutive rice growing seasons of 2017 and 2018 at Pantnagar, Uttarakhand, India for the development and validation of soil test crop response (STCR) to fertilizer and for assessing the performance of STCR-treatments as compared to the general recommended dose (GRD) in terms of yield, nutrient uptake and use efficiency, and the economics of DSR. For producing 1 Mg of rice-grain, the required nutrients (N, P, and K) were 2.01 kg, 0.44 kg, and 3.06 kg; the contribution from the soil was 22.05%, 37.34%, and 41.48%; from applied farmyard manure 23.25%, 28.34%, and 16.80%, from fertilizer 38.08%, 49.93%, and 252.98%; and from fertilizer with FYM 44.83%, 60.57%, and 278.70%; for N, P, and K, respectively. The STCR approach, with or without FYM, at both the target yields (4.5 Mg ha−1 and 5.0 Mg ha−1) markedly enhanced the grain yield (20.2% to 32.3%) and production efficiency over the GRD. It also exhibited a higher NPK uptake and use efficiency, along with better profitability, than the GRD. Therefore, the STCR-targeted yield approach could improve the yield, economics, and efficiency of nutrient use for direct seeded rice