Tillage and crop establishment effects on weeds and productivity of a rice-wheat-mungbean rotation

Impacts of future climate change and management practices to yield, eco-efficiency and global warming potential for rice-wheat rotation system

BACKGROUND

The rice-wheat rotation system (RWRS) is a predominant cropping pattern in mid-eastern China, playing a crucial role in ensuring food security. However, its intensive water and fertilizer inputs contribute significantly to greenhouse gas (GHG) emissions. With global climate warming, RWRS confronts the dual imperative of simultaneously enhancing productivity and eco-efficiency while significantly curtailing GHG emissions.

RESULTS

Future warming climate under most global climate models (GCMs) had adverse impacts on yield, water-use efficiency (WUE), nitrogen-use efficiency (NUE) and GHG intensity (GHGI) of RWRS in the central and southern regions of mid-eastern China. Compared to traditional management (TM) with high water and nitrogen inputs, optimized water and nitrogen management (OM) - utilizing intermittent irrigation and a nitrogen application rate of 390 kg ha-1 - can significantly enhance WUE and NUE while reducing GHGI, without compromising yield. Moreover, no tillage, as a conservation tillage (CT) practice could effectively mitigate the negative impacts of future climate change. The combination of OM and CT (OM + CT) can improve yield and eco-efficiency while reducing global warming potential. For RWRS with OM + CT, GHGI decreased by 45.6-60.9% under future climate scenarios compared to TM.

CONCLUSIONS

By using knowledge-based optimum management strategies, environmental risks can be reduced without sacrificing the yield of RWRS yield. This study demonstrates a useful approach with crop modelling to ensure yield for agriculture system at a lower environment cost, which can be adjusted and applied in other farming systems and regions. © 2025 Society of Chemical Industry.

False Seedbed and Stale Seedbed Against Important Broadleaf Weeds: A Case Study and a Step Closer to Agroecology

Wheat production can be reduced due to competition from weeds, with farmers relying almost exclusively on chemical solutions. However, there are alternative farming practices available. Therefore, in a field trial in Greece, we assessed the efficacy of false and stale seedbed against important broadleaf weed species and their impact on grain yield parameters. Our study determined that false seedbed resulted in a decrease in the density and biomass of broadleaf weed species like catchweed bedstraw (Galium aparine L.) up to 75% and 69% compared with the untreated control (normal seedbed preparation), respectively. The efficacy of false seedbed was higher when combined with post-emergence chemical control. Stale seedbed also resulted in adequate weed control, with a biomass reduction of up to 81%, and grain yield increased by 30% compared with the normal seedbed preparation without any herbicide use. Our results highlight the differences in the response between the weed species and also emphasize the potential of adding an alternative farming practice (like false and stale seedbed) as part of an integrated farming strategy for a sustainable and agroecological crop and weed management. In order to validate the trends observed in this case study, further field-to-field or year-to-year replication is required.

Conservation agriculture effects on ecosystem health and sustainability - A review of rice-wheat cropping system

Conventional tillage, extreme climate events, increasing weed incidence, pest and disease pressures, and diminished farm input availability negatively impact crop yield, stability, profitability, and water productivity in South Asia's rice-wheat (R-W) systems. This article reviews and evaluates the effectiveness and benefits of conservation agriculture (CA) practices in improving soil health, water productivity, and sustainability in R-W systems. CA practices focus on minimum soil disturbance, permanent soil cover, and crop rotations. Techniques such as direct seeding in rice and zero tillage in wheat are employed, supported by advancements in zero tillage sowing machinery like super-seeders. CA practices contribute significantly to ecosystem health by conserving soil and water, enhancing soil quality, reducing erosion, and improving nutrient use efficiency. They also lower production costs, increase water use efficiency, stabilize yields, promote crop diversification, and mitigate climate change effects through carbon sequestration and reduced greenhouse gas emissions. However, initial challenges include increased weed pressure and the need for suitable rice varieties for direct seeding. In conclusion, CA practices support sustainable and climate-resilient farming, improving land and water productivity, food security, and on-farm profits. Despite the benefits and growing government support, widespread adoption in South Asia remains limited. Effective support systems, including incentives, technical knowledge dissemination, and integrated weed management, are crucial for overcoming barriers and enhancing CA adoption in R-W systems.

Fertilization for Growth or Feeding the Weeds? A Deep Dive into Nitrogen's Role in Rice Dynamics in Ecuador

Rice (Oryza sativa L.) is a crucial crop for employment and agricultural output and heavily reliant on family labor. This study evaluated the effects of nitrogen levels (80, 120, and 160 kg·ha-1) on weed incidence and key agronomic variables, including vegetative growth, yield, and related traits, in Ecuador's primary rice-growing regions, Guayas and Los Ríos. A split-plot randomized complete block design was implemented using two rice varieties (INIAP-FL-Elite and SFL-11) and three planting densities (20 × 30, 25 × 30, and 30 × 30 cm). Weed incidence was higher in Los Ríos, dominated by grasses (55.28%), while Cyperaceae (46.27%) prevailed in Guayas. The data analysis included non-parametric tests to identify significant treatment effects, debiased sparse partial correlations (DSPCs) to reveal key agronomic interactions, and principal component analysis (PCA) to identify influential traits, ensuring robust and normalized interpretations. Analysis of variance indicated significant effects for all variables, with vegetative growth (VG) most affected (p < 0.001). The number of panicles (NP) and days to flowering (DF) showed significant though less pronounced effects, while the panicle length (LP) and 1000-seed weight (TSB) exhibited moderate responses. The DSPCs highlighted the grains per panicle (GP) and total biomass (SB) as critical variables, with significant correlations between the days to flowering and the tiller count at 55 days (r = 0.750, p < 0.001) and between the vegetative growth and the total biomass (r = 0.678, p < 0.001). PCA explained 58.8% of the total variance, emphasizing the days to flowering, plant height, total biomass, and yield as the most influential traits. These findings underline the importance of integrated nutrient and weed management strategies tailored to Ecuador's agroecological conditions.

Effect of conservation agriculture on soil fungal diversity in rice-wheat-greengram cropping system in eastern Indo-Gangetic plains of South Asia

Introduction

Conservation agriculture (CA) is emerging as an eco-friendly and sustainable approach to food production in South Asia. CA, characterized by reduced tillage, soil surface cover through retaining crop residue or raising cover crops, and crop diversification, enhances crop production and soil fertility. Fungal communities in the soil play a crucial role in nutrient recycling, crop growth, and agro-ecosystem stability, particularly in agricultural crop fields.

Methods

This study investigates the impact of seven combinations of tillage and crop residue management practices of agricultural production systems, including various tillage and crop residue management practices, on soil fungal diversity. Using the Illumina MiSeq platform, fungal diversity associated with soil was analysed.

Results and discussion

The results show that the partial CA-based (pCA) production systems had the highest number of unique operational taxonomic units (OTUs) (948 OTUs) while the conventional production system had the lowest number (665 OTUs). The major fungal phyla identified in the topsoil (0-15 cm) were Ascomycota, Basidiomycota, and Mortierellomycota, with their abundance varying across different tillage-cum-crop establishment (TCE) methods. Phylum Ascomycota was dominant in CA-based management treatments (94.9±0.62), followed by the partial CA (pCA)-based treatments (91.0 ± 0.37). Therefore, CA-based production systems play a crucial role in shaping soil fungal diversity, highlighting their significance for sustainable agricultural production.

Influence of conservation agriculture-based production systems on bacterial diversity and soil quality in rice-wheat-greengram cropping system in eastern Indo-Gangetic Plains of India

Introduction

Conservation agriculture (CA) is gaining attention in the South Asia as an environmentally benign and sustainable food production system. The knowledge of the soil bacterial community composition along with other soil properties is essential for evaluating the CA-based management practices for achieving the soil environment sustainability and climate resilience in the rice-wheat-greengram system. The long-term effects of CA-based tillage-cum-crop establishment (TCE) methods on earthworm population, soil parameters as well as microbial diversity have not been well studied.

Methods

Seven treatments (or scenarios) were laid down with the various tillage (wet, dry, or zero-tillage), establishment method (direct-or drill-seeding or transplantation) and residue management practices (mixed with the soil or kept on the soil surface). The soil samples were collected after 7 years of experimentation and analyzed for the soil quality and bacterial diversity to examine the effect of tillage-cum-crop establishment methods.

Results and Discussion

Earthworm population (3.6 times), soil organic carbon (11.94%), macro (NPK) (14.50-23.57%) and micronutrients (Mn, and Cu) (13.25 and 29.57%) contents were appreciably higher under CA-based TCE methods than tillage-intensive farming practices. Significantly higher number of OTUs (1,192 ± 50) and Chao1 (1415.65 ± 14.34) values were observed in partial CA-based production system (p ≤ 0.05). Forty-two (42) bacterial phyla were identified across the scenarios, and Proteobacteria, Actinobacteria, and Firmicutes were the most dominant in all the scenarios. The CA-based scenarios harbor a high abundance of Proteobacteria (2-13%), whereas the conventional tillage-based scenarios were dominated by the bacterial phyla Acidobacteria and Chloroflexi and found statistically differed among the scenarios (p ≤ 0.05). Composition of the major phyla, i.e., Proteobacteria, Actinobacteria, and Firmicutes were associated differently with either CA or farmers-based tillage management practices. Overall, the present study indicates the importance of CA-based tillage-cum-crop establishment methods in shaping the bacterial diversity, earthworms population, soil organic carbon, and plant nutrient availability, which are crucial for sustainable agricultural production and resilience in agro-ecosystem.