Search

Abstract Soybean-wheat sequence, one of the most vital cropping systems for farmers, has been suffering for productivity stagnation and decline due to several factors. Strategic management of the inputs particularly the nutrients could aid the crops achieve optimum growth and yield. Keeping this in mind, four years of field experiment was conducted to study the effect of combining inorganic as well as organic nutrient sources using soil-test-crop-response (STCR) approach in a randomized block design having ten treatments including control, 100% Recommended Dose of Fertilizers (RDF), 50% RDF, 100% RDF + 5 kg Zn ha−1 (100% RDF + Zn), 100% RDF + 5 t farmyard manure ha−1 (100% RDF + FYM), 50% RDF + 5 t farmyard manure ha−1 (50% RDF + FYM), STCR inorganic with target yield-I (STCRI TY-I), STCR inorganic with TY-II, STCR integrated with TY-I (STCRO TY-I) and STCR integrated with TY-II (STCRO TY-II) with each treatment replicated thrice. The STCR equations were tailored for the experimental location and used to calculate the fertilizer requirements. Plant growth, yield, system yield, sustainability and economics, changes in soil parameters were analyzed during the study. The STCRO TY-II treatment showed 122.4 and 73.3% increase in yield of soybean and wheat over control, respectively and those were at par with the highest values recorded from 100% RDF + FYM treatment. Despite having low gross and net returns, decrease in benefit cost ratio was marginal (0.86%) in STCRO TY-II as compared to 100% RDF + FYM which indicated better utilization of resources with comparatively lower investment. In addition to that, it also performed reasonably well in improving soil available nutrient status (positive balance in available N, P, K and organic carbon), partial factor productivity of nutrients and sustainable yield index (2.43 times over control). The study elucidated significance of integrated nutrient management specially STCRO TY-II in improving soil health, optimizing yield and assuring economic sustainability in soybean-wheat cropping system.

A two-year field study was carried out during winter (rabi) seasons of 2020–21 and 2021–22 at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi with the aim of examining the impacts of various methods of tillage, residue management and nitrogen (N) application on wheat (Triticum aestivum L.) yield, water use efficiency (WUE), and nitrogen use efficiency in terms of Partial Factor Productivity of Nitrogen (PFPN). The study utilized a split-split plot design with 3 replications, where the main plot consisted of two tillage systems [conventional tillage (CT) and no tillage (NT)], the subplot comprised 2 residue levels [maize residue @5 t/ ha (R+) and no residue (R0)], and the sub-sub plot involved 3 N levels [60, 120, and 180 kg N/ha, representing 50% (N60 kg N/ha), 100% (N120 kg N/ha), and 150% (N180 kg N/ha)] respectively. The results indicated that both tillage and residue management considerably influenced the grain and biomass yield of wheat. Over the two years, NT exhibited a 7% higher WUE compared to CT, but the change was insignificant. However, in years with lower rainfall, crop residue mulching had a significant positive impact on WUE, while in years with higher rainfall; its effect on WUE was insignificant. Moreover, tillage practices had a considerable effect on the PFPN. In the year 2020–21, PFPN under NT was 3.59% higher than under CT, and in the year 2021–22, it was 2.06% higher. Furthermore, with an increase in N levels, WUE showed a substantial increase, while PFPN decreased.

A two-year field study was carried out at the Indian Agricultural Research Institute New Delhi, from rabi 2020-21 to 2021-22, with the aim of examining the impacts of tillage and residue management on yield, greenhouse gases (GHGs) emissions, global warming potential (GWP) and carbon efficiency ratio (CER) of wheat in a split plot design. The results indicated that both tillage and residue management significantly influenced the grain and biomass yield of wheat. In comparison to conventional tillage (CT), no-tillage (NT) resulted in a substantial reduction of CO2-C emissions by 19.9%, while it led to a notable increase of N2O-N emissions by 11.6%. However, there was a notable and significant rise in GHG emissions with crop residue mulching, registering on an average 20.79% higher emissions compared to residue removal for both the years. The GWP was overall lower in case of NT as compared to CT plots. The highest CER was observed in NTR+ (3.07) during 2020-21 and in NTR0 (3.12) during 2021-22 due to lower CO2 emissions and higher C fixation in both years. Therefore, it may be recommended that wheat can be cultivated in a semi-arid environment with no tillage and residue mulching to provide a comparable yield in addition to lower GHG emissions and GWP and higher CER compared to the farmers’ practice of CT and residue removal.

Water, nutrients, and energy are the three main inputs in agricultural production and recently there has been a drop in the factor productivity of these inputs because of their improper management and deterioration of soil health. To maximize agricultural productivity while lowering strain on natural resources, the best synergistic combinations of tillage, residue, nitrogen, and water management should be identified for improving resource use efficiency of wheat. Hence, an attempt has been made to evaluate the impact of contrasting tillage, crop residue mulch, nitrogen, and irrigation interaction on yield, radiation productivity (RP), and water productivity (WP) of wheat in a split-factorial design. Results showed that wheat yield was higher under no-tillage (4.8%) than that of conventional tillage. Crop residue mulch (CRM) and higher nitrogen application enhanced RP, WP, and yield of wheat; although RP increased with increase in nitrogen application up to 100% recommended dose of nitrogen (RDN). CRM significantly reduced the seasonal evapotranspiration (6.0‒7.2%) as compared to residue removal treatment. Deficit irrigation enhanced the WP while it lowered the crop yield significantly. Therefore, wheat can be grown under no-tillage, CRM, 100% RDN with deficit irrigation to obtain higher WP but with full irrigation to obtain higher yield, and RP in the semiarid climate of India.

The effect of duration of conservation agriculture adoption on soil carbon dynamics and system sustainability was evaluated on farms of 30 villages in the Nilokheri block of Karnal district, Haryana, India. Sustainability was evaluated, in which a number of soil physical, chemical, and biological parameters were measured and a Sustainability Index (SI) was applied. Soil samples were collected from existing conservation agriculture (CA) and conventional tillage (CT) farms. Villages under CA practices were subdivided as CA3, CA6, and CA9 based on the number of years of CA practice adoption. Results showed that bulk density (BD) of 0-15 cm soil depth was 7% greater in CA3 plots, whereas in CA6 and CA9 plots BD values were only 2% and 3% higher than CT. Soil organic carbon (SOC) in 0-15 cm soil depth was found to be greater by 16.32% in CA3 than CT plots, whereas SOC was higher by 38.77% and 61.22% in CA6 and CA9. In CA, for the 0–15 and 15-30 cm soil depths, labile pools were 36% and 22% greater than CT, respectively. For both the soil depths in CA, the recalcitrant pool was 12% and 9% more than CT, respectively. Microbial biomass carbon (MBC) values of the 0-15 cm soil depth were increased over CT by 18.57%, 47.08%, and 71.5% for CA3, CA6, and CA9 respectively. In CA plots, the SI of 0-15 cm soil depth ranged between cumulative ratings (CR) of 18–21, which indicates that CA practice is “sustainable” for both soil depths. For CT, CR ranged from 25 to 30 for both soil depths resulting in a SI of “sustainability with high input”. Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) scores showed that SOC had the maximum weight (0.96) towards sustainability, giving it a rank of 1. Effective rooting depth (ERD), BD, texture, and wilting point (WP) ranked 2, 3, 4 and 5, respectively, indicating their corresponding weight of contribution towards the SI. Farmers in the Karnal district should be encouraged to adopt CA practices as they can increase SOC and move the systems from “sustainable with high input” to “sustainable”.

For sustainable crop production and maintenance of soil health, conservation agriculture (CA) practices provides an opportunity for improving soil structure and physical health, nutrient and water use efficiency, soil organic carbon and mitigation of greenhouse gases emission from agriculture. CA is primarily based on four crop management practices such as minimum soil disturbance or no-tillage; permanent or semi-permanent retention of crop residue; crop rotation and control traffic. Different CA management practices affect crop yield as well as soil properties. CA makes necessary modifications in different soil hydro-physical properties, viz. increase in soil water infiltration, reduction in water runoff and soil loss, and reduction in evaporation loss. No tillage (NT), residue retention and crop rotation combined effect the soil organic carbon concentration. Different crop rotations and residue retentions and crops with different rooting depths used in CA practices have proved to reduce the compaction constraints.CA can help to mitigate GHG emissions, viz methane (CH4) and nitrous oxide (N2O) from agriculture by improving soil C sequestration, enhancing soil quality, nitrogen and water use efficiencies, and decreasing fuel consumption. But effect of CA and conventional agricultural practices of porosity and pore size distribution is very much limited. When CA is practiced for six to ten years there is improvement in soil structure, porosity and pore size distribution, macro-micro faunal activity, and organic matter content..The soil under ZT has the lowest porosity as compared to conventional management practices. The highest porosity and the maximum connected pores are frequently seen in conventionally tilled soil. In this paper, an attempt has been made to review the variation of porosity and pore size distribution and other soil physical properties under conservation agricultural practices.