Search Results (13)

The sustainable productivity of rice–wheat cropping systems relies on soil health, and soil health can be positively influenced by treating previous crop residues using conservation tillage practices. The present study examined the impact of three rice residue-management practices under zero-tilled wheat (ZTW) and conventionally tilled wheat (CTW), along with two rice-sowing practices, during rice cultivation on soil functional microbial diversity, physiological profiling, and grain yields of rice and wheat. Anchored residues (ARs) under ZTW exhibited significantly (p ≤ 0.05) high average well color development—31.43% more than CTW with no residue (NR). CTW with residue burning (BUR) showed a 5.42% increase in the Shannon diversity index compared to CTW-NR. Substrate richness was 10.02% higher in CTW-BUR compared to CTW-NR. CTW-BUR demonstrated the highest 17.98% increase in the Shannon evenness index compared to CTW-NR. The direct-seeded rice (DSR) system generally surpassed puddled transplanted rice (PTR) in most indices, except for the Shannon evenness index values. ZTW-AR exhibited the highest utilization of amino acids, carboxylic acids, and phenolic compounds, while CTW-BUR exhibited the highest utilization of carbohydrates and polymers utilization, and ZTW with no-residue (NR) exhibited the highest utilization of amines. Rice and wheat grain yields were highest with full residue in ZTW and lowest in CTW-NR. PTR supported higher rice yields, while DSR was superior for wheat. These findings highlight the favorable role of residue retention with no tillage during wheat cultivation in the maintenance of soil quality and rice–wheat productivity. Full article

Extreme precipitation and flooding frequency associated with global climate change are expected to increase worldwide, with major consequences in floodplains and areas susceptible to flooding. The purpose of this review was to examine the effects of flooding events on changes in soil properties and their consequences on agricultural production. Flooding is caused by natural and anthropogenic factors, and their effects can be amplified by interactions between rainfall and catchments. Flooding impacts soil structure and aggregation by altering the resistance of soil to slaking, which occurs when aggregates are not strong enough to withstand internal stresses caused by rapid water uptake. The disruption of soil aggregates can enhance soil erosion and sediment transport during flooding events and contribute to the sedimentation of water bodies and the degradation of aquatic ecosystems. Total precipitation, flood discharge, and total water are the main factors controlling suspended mineral-associated organic matter, dissolved organic matter, and particulate organic matter loads. Studies conducted in paddy rice cultivation show that flooded and reduced conditions neutralize soil pH but changes in pH are reversible upon draining the soil. In flooded soil, changes in nitrogen cycling are linked to decreases in oxygen, the accumulation of ammonium, and the volatilization of ammonia. Ammonium is the primary form of dissolved inorganic nitrogen in sediment porewaters. In floodplains, nitrate removal can be enhanced by high denitrification when intermittent flooding provides the necessary anaerobic conditions. In flooded soils, the reductive dissolution of minerals can release phosphorus (P) into the soil solution. Phosphorus can be mobilized during flood events, leading to increased availability during the first weeks of waterlogging, but this availability generally decreases with time. Rainstorms can promote the subsurface transport of P-enriched soil particles, and colloidal P can account for up to 64% of total P in tile drainage water. Anaerobic microorganisms prevailing in flooded soil utilize alternate electron acceptors, such as nitrate, sulfate, and carbon dioxide, for energy production and organic matter decomposition. Anaerobic metabolism leads to the production of fermentation by-products, such as organic acids, methane, and hydrogen sulfide, influencing soil pH, redox potential, and nutrient availability. Soil enzyme activity and the presence of various microbial groups, including Gram+ and Gram− bacteria and mycorrhizal fungi, are affected by flooding. Waterlogging decreases the activity of β-glucosidase and acid phosphomonoesterase but increases N-acetyl-β-glucosaminidase in soil. Since these enzymes control the hydrolysis of cellulose, phosphomonoesters, and chitin, soil moisture content can impact the direction and magnitude of nutrient release and availability. The supply of oxygen to submerged plants is limited because its diffusion in water is extremely low, and this impacts mitochondrial respiration in flooded plant tissues. Fermentation is the only viable pathway for energy production in flooded plants, which, under prolonged waterlogging conditions, is inefficient and results in plant death. Seed germination is also impaired under flooding stress due to decreased sugar and phytohormone biosynthesis. The sensitivity of different crops to waterlogging varies significantly across growth stages. Mitigation and adaptation strategies, essential to the management of flooding impacts on agriculture, enhance resilience to climate change through improved drainage and water management practices, soil amendments and rehabilitation techniques, best management practices, such as zero tillage and cover crops, and the development of flood-tolerant crop varieties. Technological advances play a crucial role in assessing flooding dynamics and impacts on crop production in agricultural landscapes. This review embarks on a comprehensive journey through existing research to unravel the intricate interplay between flooding events, agricultural soil, crop production, and the environment. We also synthesize available knowledge to address critical gaps in understanding, identify methodological challenges, and propose future research directions. Full article

A three-year field experiment was carried out to assess the efficacy of various tillage and residue management practices, as well as weed management approaches, in a rice–wheat–green gram rotation. The treatments included: conventional till transplanted rice–conventional till wheat–fallow (T₁); conventional till transplanted rice–zero-till wheat–zero-till green gram (T₂); conventional till direct-seeded rice—conventional-till wheat—zero-till green gram (T₃); zero-till direct-seeded rice—zero-till wheat—zero-till green gram (T₄); zero-till direct-seeded rice + residue zero-till wheat + residue zero-till green gram (T₅). In weed management, three treatments are as follows: recommended herbicides (W₁); integrated weed management (W₂); and unweeded (W₃). The integrated weed management treatment had the lowest weed biomass, which was 44.3, 45.3, and 33.7% lower than the treatment W₃ at 30 and 60 days after sowing and harvest, respectively. T₁ grain and straw yielded more than T₂ in the early years than in subsequent years. The conventional till transplanted rice–zero-till wheat–zero-till green gram system produced 33.6, 37.6, and 27.7% greater net returns than the zero-till direct-seeded rice—zero-till wheat—zero-till greengram system, respectively. Conventional till transplanted rice–conventional till wheat–fallow had the biggest reduction (0.41%) in soil organic carbon from the initial value. The findings of the study demonstrated that adopting the transplanting method for rice, followed by zero tillage for wheat and green gram, enhanced productivity and profitability, while simultaneously preserving soil health. Full article

A growing population, changing climate, scarcity of resources, and the urgent need to achieve sustainable development goals makes it imperative to reimagine agriculture in a way that makes it economically profitable, climate-resilient, resource-efficient. Traditional rice production technology involving puddling and transplanting has often been criticized for its inefficient resource utilization, high cost of production, and emission of greenhouse gases such as methane. Direct-seeded rice (DSR), promoted for its climate-resilient nature, is often utilized by farmers in three different ways: broadcasting, line sowing, and zero tillage. However, these establishment methods have certain advantages and limitations, as perceived by farmers. The present study attempts to closely study the crop performance of rice under the abovementioned crop establishment methods. The study was conducted in farmers’ fields in a way where both the farmers’ freedom and research conditions were equally taken care of. The study aims to analyze crop performance while emphasizing farmers’ field-based knowledge to ensure a lab-land-lab loop for understanding the scope of refinement in agronomic as well extension strategies. The results of this study reveal the superiority of zero tillage over broadcasting and line sowing in terms of crop performance and economic performance in the northwest alluvial plain zone of Bihar. The study has also identified the constraints associated with adoption of line sowing and zero tillage. Full article

Conventional tillage practices coupled with irrational use of fertilizer in the rice-wheat cropping system (RWCS) often leads to poor productivity, low nutrient use efficiency, and cause environmental pollution. Conservation tillage with surface residue retention in combination with intelligent nutrient management might improve productivity and use efficiency of water as well as nutrients in zero-till direct-seeded rice (ZTDSR). Keeping this in mind, during the kharif season of 2018 and 2019, a trial was carried out at the ICAR-IARI in New Delhi to investigate the varying nutrient management approaches following a precise manner in DSR. The treatments consisted of soil-test-based NPK (STB-NPK) and Nutrient Expert^® (+LCC_N) based NPK (NE-NPK) applications, Fertilizer applied at the recommended dose (RDF) [120-60-40 kg/ha NPK], the state recommended NPK (110-50-40 kg/ha) and omission plot technique of NPK [i.e., STB (N₀PK, NP₀K & NPK₀); SR (N₀PK, NP₀K & NPK₀) and NE-(N₀PK, NP₀K & NPK₀)]. The results indicated that STB NPK application led to a 12% higher grain yield over RDF. However, NE-NPK resulted in a 7% and 35% increase in N (AEN) agronomic efficiency and P (AEP) over the STB-NPK application respectively. In contrast, AE_k was 24% higher in STB-NPK over NE-NPK treatment. The comparison of two years’ results that the first year performed better than the succeeding year in these respect (productivity and AE) except in the case of AE_k. The N₂O emission in NE-NPK treatment was also significantly reduced (49%) over the control (no N). STB-NPK treatment also improved profitability by 22% over RDF. Precision nutrient management (PNM) increased the crop yield, income, and use efficiency of nutrients and water and reduced greenhouse gas (GHG) emissions of DSR in Southeast Asia. Full article

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. Full article

Interest in conservation measures, including reduced tillage, zero tillage, and crop residue retention, is growing in major rice growing areas of the world; particularly in the Indo-Gangetic plains. Of late, research interest is increasing in India for a specialised method of cultivation known as natural farming, which aims at maintain the functional biodiversity of the farm with little or no use of external inputs. With the increasing water crisis at a global level, it became imperative to develop technologies that can reduce the water use, particularly in water-guzzling low land paddy, by developing alternate cultivation methods; direct seeded rice is one such technology. A two-year field experiment was carried out at two locations during 2019–2020 and 2020–2021 to find out the impact of different cultivation and varieties on the productivity and profitability of the rice–wheat cropping system. The experiments were conducted in split plot design, replicated thrice, with cultivation practices in the main plot and varieties of both wheat and rice in the sub plot. The results so obtained reveal that conventional tillage significantly out yielded other methods of cultivation in both the crops at both the locations, while significantly lower grain yield in both crops was observed from natural farming. Adoption of reduced tillage, zero tillage and natural farming reduced the grain yield of wheat by 4.6%, 10.9%, and 59.4% over conventional tillage, while the corresponding decline in grain yield of rice was 10.8%, 16.1%, and 34.0% with reduced tillage, zero tillage, and natural farming, respectively. Among the varieties tested, HPW 368 and Him Palam Lal Dhan 1 (HPR 2795) produced significantly higher grain yield of wheat and rice, respectively, at both the locations during both years. Conventional tillage among cultivation practices and HPW 368 and Him Palam Lal Dhan 1 (HPR 2795) among wheat and rice varieties also proved to be better in terms of various economic indicators, including gross return, net return, and ratio benefit cost ratio (B:C ratio). Full article

Climate-smart agriculture (CSA) practices are becoming increasingly important due to their better adaptability to harsh climatic conditions (in general) and the unpredictability of monsoons in India (in particular). Conventional rice cultivation (e.g., PTR) involves intensive tilling followed by intensive puddling in standing water that destroys the soil aggregation and depletes carbon pools. Therefore, alternative crop establishment methods need to be devised for the sustainability of system productivity, and the suitabilities of potential oilseeds and pulses need to be tested for cropping intensification in rice-fallow regions. Hence, an ongoing experiment (implemented in 2016) was evaluated to identify the appropriate CSA management practices in restoring soil C and physical health under diversified cropping systems in the rice-fallow system of eastern India. Six tillage and crop establishment methods along with residue management were kept as the main plots [zero-till-direct-seeded rice (ZTDSR), conventional-till-DSR (CT-DSR), puddled transplanted rice (PTR), ZTDSR with rice residue retentions (ZTDSR_R+), CTDSR with rice residue retention (CTDSR_R+), PTR with rice residue retention (PTR_R+)] while five winter/post-rainy crops (oilseeds and pulses) were raised in a subplot. In the ZTDSR_R+ production system, soil macro-aggregate (%), macro-aggregate-associated C, MWD, and GMD of aggregates increased by 60.1, 71.3, 42.1, and 17.1%, respectively, in comparison to conventional tillage practices (PTR). The carbon management index (CMI) was 58% more in the ZTDSR_R+ production system compared to PTR. Among the winter crops, chickpeas recorded higher values of soil structural indices and C content. In the PTR production system, system productivity, in terms of rice equivalent yield, was comparable to ZTDSR_R+. ZT with residue retention in rice followed by post-rainy/winter pulses led to higher C content and structural stability of the soil. Thus, CSA management practices can improve the crop productivity as well as soil health of rice-fallow production systems of eastern India and comparable agroecotypes of South Asia. Full article

The escalating scarcity of irrigation water, transplantation of rice on light-textured soils and labour cost acted as major drivers for the transition towards direct-seeded rice (DSR) cultivation from the conventionally flooded transplanting system. Despite these advantages, DSR is a challenge in light texture soil due to heavy weed infestation and a slight decline in crop yield. The weeds compete for nutrients and have an adverse effect on the growth and yield of crops. Hence, to assess the removal of macro and micronutrients by weeds and direct-seeded rice, a field experiment was carried out on sandy loam soil for two consecutive Kharif seasons (2018 and 2019). Three treatments from rice, namely: DSR under zero tillage (DSR-ZT), DSR under conventional tillage (DSR-CT) and DSR under reduced tillage (DSR-RT) were taken as main plots with three tillage treatments in wheat, namely: Conventional tillage without rice straw (CTW-R), Zero tillage without rice straw (ZTW-R) and Zero tillage with straw as mulch using Happy Seeder (ZTW+R) as subplots, replicated thrice. Among the rice establishment methods, DSR-RT showed an edge in terms of rice grain and straw yield (6.18 and 8.14 Mg ha⁻¹, respectively) as well as macro- and micronutrient uptake by rice. Under management practices, ZTW+R proved as an efficient strategy in terms of yield and nutrient uptake by crops. The contribution of weeds towards biomass production was maximum under the ZTW-R (9.44%) treatment followed by DSR-ZT (7.72%). The nutrient budgeting showed that macro- and micronutrient removal by weeds was minimum under reduced tillage (24.51 and 50.35%, respectively), whereas it was 21.88 and 44.87% when wheat was grown under conventional tillage without rice straw. In overall, the research study concluded that weeds on an average remove 25.65 % macronutrients (N, P, K) and 51.47% of micronutrients (Zn, Cu, Fe and Mn) in DSR under rice-wheat cropping system. Full article

In Nepal and elsewhere in the Indo-Gangetic plains where rice-wheat is a major crop rotation, interest in conservation practices such as direct-seeding of rice on zero-tilled soil and retention of crop residue is increasing. However, the use of herbicide is increasing in the region due to a shortage of labor and its ease of operation compared to manual weeding. This field experiment was conducted to identify the response of rice to tillage and planting systems, level of wheat residue retention and weed managements under rice-wheat cropping system. This study was conducted during three growing seasons of rice (June through November) in 2014, 2015 and 2016 at the National Wheat Research Program (NWRP), Rupandehi, Nepal. The experiment was conducted in a split-split plot design. Tillage and planting systems were the main plots where rice was either transplanted on puddled field managed with conventional tillage (CT) or direct seeded on zero till (ZT) soil. The level of residue retention was the sub-plot which included three levels of residue retention as whole (WR), partial (PR) or no (NR) retention. Forms of weed management were the sub-sub plots with manual weeding (MW) compared with chemical weeding (CW) through the application of bispyribac-sodium. Each treatment combination consisted of three replicated units. Averaged across the years, grain yield of rice under the CT system (4.8 t ha⁻¹) was significantly higher than ZT (4.4 t ha⁻¹). Increased level of wheat residue retention increased grain yield consistently in all three years. Grain yield was not influenced by systems of weed management. The following conclusions were drawn from the results: (i) rice grain yield might decrease under a direct-seeded ZT system more than the conventional system, (ii) wheat residue retained in the field can increase rice grain yield significantly, and (iii) application of bispyribac-sodium could be equally effective as manual weeding for weed control in both tillage/planting systems of rice. Full article

Rice-based intensive cropping systems require high input levels making them less profitable and vulnerable to the reduced availability of labor and water in Asia. With continuous conventional puddled rice transplanting, the situation is exacerbated by damaged soil structure, declining underground water and decreasing land and water productivity. To minimize these negative effects a range of new crop establishment practices have been developed (zero tillage, dry direct seeding, wet direct seeding, water seeding, strip planting, bed planting, non-puddled transplanting of rice, mechanical transplanting of rice crop and combinations thereof) with varying effects on soil health, crop productivity, resource saving and global warming mitigation potential. Some of these allow Conservation Agriculture (CA) to be practiced in the rice-based mono-, double- and triple cropping systems. Innovations in machinery especially for smallholder farms have supported the adoption of the new establishment techniques. Non-puddling establishment of rice together with increased crop residue retention increased soil organic carbon by 79% and total N (TN) in soil by 62% relative to conventional puddling practice. Rice establishment methods (direct seeding of rice, system of rice intensification and non-puddled transplanting of rice) improve soil health by improving the physical (reduced bulk density, increased porosity, available water content), chemical (increased phosphorus, potassium and sulphur in their available forms) and biological properties (microbiome structure, microbial biomass C and N) of the soil. Even in the first year of its practice, the non-puddled transplanting method of rice establishment and CA practices for other crops increase the productivity of the rice-based cropping systems. Estimates suggest global warming potential (GWP) (the overall net effect) can be reduced by a quarter by replacing conventional puddling of rice by direct-seeded rice in the Indo-Gangetic Plains for the rice-based cropping system. Moreover, non-puddled transplanting of rice saves 35% of the net life cycle greenhouse gases (GHGs) compared with the conventional practice by a combination of decreasing greenhouse gases emissions from soil and increasing soil organic carbon (SOC). Though the system of rice intensification decreases net GHG emission, the practice releases 1.5 times greater N₂O due to the increased soil aeration. There is no single rice establishment technology that is superior to others in all circumstances, rather a range of effective technologies that can be applied to different agro-climates, demography and farm typologies. Full article

The Eastern Gangetic Plains (EGPs) has the potential to become a major contributor to South Asian regional food security, despite the world’s highest concentration of rural poverty and a strong dependence on agriculture. A regional project entitled ‘Sustainable and Resilient Farming Systems Intensification (SRFSI), managed by CIMMYT with over 20 partners with ACIAR/DFAT funding was launched in May 2014 to sustainably reduce the poverty. A total of 436 farmer-participatory on-farm trials comparing the performance of three conservation agriculture based sustainable intensification (CASI) technologies like Zero/Strip till as base (ZT/ST) over the conventional tillage (CT; T1) practices were conducted across eight districts in northwest Bangladesh, Bihar and West Bengal in India, and eastern Terai of Nepal for two consecutive years i.e. 2015/16 and 2016/17. The three CASI treatments comprised a “partial CASI” option (T2: at least one crop in the cropping system established with ZT management) and two “full CASI” options (T3 and T4: all crops established with ZT/ST management; in T3 rice was direct seeded (DSR) while in T4, it was unpuddled transplanted (UPTR)). Multicriteria assessment showed an increase in rice equivalent system yield (RESY) by 4%, gross margin by 19–20%, input water productivity by 7–9% and energy productivity by 13–14% while decrease in requirements for irrigation water, energy, labor and the production cost by 15–17%, 10–11%, 32–38% and 15–18% respectively, and reduction in CO₂ equivalent emission by 8–13% in full CASI over CT. CASI has shown great promise for food security and livelihood improvement at small scale. Full article

Soil fertility in Ghana continues to decline due to the overdependency on farm machinery to till the land coupled with the continuous application of mineral fertilizer, which has a resultant effect on agricultural non-point source (AgNPS) pollution. A two-year field experiment was conducted to evaluate the effects of different tillage methods on soil properties, nitrogen loss reduction and rice productivity of a gleysol, developed over granite. Five tillage methods—namely, zero tillage direct seeding (ZTDS), zero tillage transplanting (ZTTS), reduced tillage direct seeding (RTDS), reduced tillage transplanting (RTTS), and conventional tillage (CT)—were studied in a Randomized Complete Block Design (RCBD) with three replicates. After two cropping seasons, soil bulk density was in the order of (ZTTS = ZTDS) ˃ RTDS ˃ RTTS ˃ CT. ZTDS and ZTTS were associated with significantly higher levels of nutrients in the top soil (0–20 cm) as compared with the rest of the treatments. Plant height was in the order of CT > RTTS = ZTTS > RTDS > ZTDS. The highest grain yield was recorded by both CT and ZTTS significantly different from the rest of the treatments. ZTDS recorded the highest stover yield for both years. Subsequently, CT was associated with high release of potential pollutant loads which could lead to AgNPS pollution, as is evident from the high nutrient loss. Considering the high nutrient concentration at 0–20 cm, the reduced nutrient movement and the corresponding yield improvement, ZTDS and ZTTS are recommended for farmers in Ghana to ensure sustainable rice production, reduce AgNPS pollutant movement and ultimately provide an eco-protective and friendly environment for sustainable rice production. Full article