Maize productivity in Southeastern Europe is increasingly affected by climatic variability, necessitating agronomic strategies to maintain yield under irrigated conditions. This study evaluated the effects of conventional tillage, minimum tillage, and no-tillage on maize yield, yield components, and weed dynamics, and analyzed the interaction between tillage intensity and hybrid performance under irrigated cambic chernozem conditions in Southeastern Romania. A three-year field experiment (2023–2025) was conducted as a randomized complete block design with three replications using three maize hybrids (P0900, P0937, and P1441) under sprinkler irrigation. Grain yield, kernel weight per ear, kernel number per ear, thousand-kernel weight, plant density, and weed density were analyzed using ANOVA, linear mixed models, and regression analysis. Grain yield ranged from 10.66 to 11.46 t ha⁻¹ across years, with the hybrid exerting the strongest effect on all productivity parameters. P0900 recorded the highest yield (12.43 t ha⁻¹) and the lowest associated weed density. Weed density increased from 207.44 plants m⁻² under conventional tillage to 266.11 plants m⁻² under no-tillage and was negatively associated with yield components and grain yield. Significant tillage × weed-density interactions indicated steeper productivity declines in reduced-tillage systems, particularly no-tillage. The results suggest that the agronomic performance of conservation-oriented tillage systems under irrigation depends strongly on hybrid adaptability and effective weed-management strategies.

This study investigates the impact of soil tillage systems on the productivity and economic performance of winter oilseed rape (Brassica napus L.), under the pedoclimatic conditions of Southern Dobrogea (Mereni, Constanța County, Romania), over three consecutive agricultural years (2021–2024). The experiment was conducted at the Iancu Ionuț Individual Enterprise, evaluating three commercial hybrids: Kicker (Rapool), Umberto (KWS), and PT 264 (Corteva Pioneer), cultivated under conventional and no-till management systems. The research aimed to assess the interaction between genotype, tillage system, and environmental factors on key yield components (plant height, number of siliques per plant, thousand-seed weight, test weight, and seed yield), as well as to determine the economic efficiency of both technological variants. Statistical analyses included ANOVA, Pearson correlations, and multiple regression models to identify the main determinants of yield variability.Results demonstrated that, although the no-till system produced on average 7–11% lower yields compared to conventional tillage (ranging from 2.7 to 3.1 t·ha), it significantly reduced production costs by 10–12%, maintaining a comparable profitability level and a higher return on investment. Furthermore, in years characterized by low rainfall (<350 mm), the no-till plots exhibited superior soil moisture conservation and better plant uniformity, reflecting enhanced resilience to drought stress. The regression model (R² = 0.999) confirmed that rainfall amount and seed test weight were the primary factors influencing yield performance. The findings highlight that no-till technology, while slightly reducing productivity, ensures greater economic stability and resource efficiency under semi-arid conditions. Its integration into the crop rotation systems of Southeastern Romania could therefore represent a strategic pathway toward sustainable intensification, balancing productivity, profitability, and environmental protection.

Research Journal of Agricultural Science

Climate change and increasing drought frequency represent major challenges for agricultural systems in semi-arid regions of Southeastern Europe. In this context, identifying resilient crops capable of maintaining productivity under water-limited conditions is essential for sustainable agriculture. The present study evaluates the agronomic performance and resilience of three grain sorghum hybrids (Willy, Legend and Anggy) cultivated under rainfed conditions in southern Dobrogea (Romania) on cambic chernozem soil during the 2021–2024 period. The experiment investigated the influence of planting date on phenological development, thousand-kernel weight (TKW), plant density and grain yield. Two planting dates were tested (April 4 and May 2), and the results represent multiannual averages over three agricultural years. Early planting ensured balanced vegetative growth, optimal grain moisture at harvest and the highest yields, reaching 5319 kg/ha for the Legend hybrid. Delaying planting by 28 days resulted in an average yield reduction of about 30%, associated with decreases in TKW and final plant density. ANOVA analysis revealed a highly significant effect of planting date (p = 0.001) and a significant effect of hybrid (p = 0.01) on yield. A strong correlation between TKW and yield (r = 0.920; R² = 0.847) and between precipitation and yield (r = 0.872; R² = 0.760) highlights the influence of climatic factors on crop performance. The results confirm that sorghum is a climate-resilient crop suitable for sustainable agriculture in arid and semi-arid agroecosystems.

Seasonal climatic variability represents a major constraint on sunflower (Helianthus annuus L.) production in semi-arid environments, yet interannual and cultivar-related variation under long-term no-till management remains insufficiently characterized. This study evaluated interannual and cultivar-related variation in sunflower productivity and seed quality during three consecutive growing seasons (2023–2025) under rainfed long-term no-till conditions in the Dobrogea Region of Romania. Three commercial hybrids (Averon SU, Demetra, and Helesun) were evaluated in a randomized complete block design with three replications, while agronomic management remained unchanged throughout the experimental period. Agronomic traits, yield components, and seed quality parameters were analyzed using analysis of variance, paired t-tests, Pearson’s correlation analysis, and partial redundancy analysis (RDA). Pronounced interannual climatic variability was accompanied by substantial differences in sunflower performance. Mean seed yield reached 2169.06 kg ha⁻¹ in 2023, declined to 848.08 kg ha⁻¹ in the drought-affected 2024 season, which had the lowest March–August precipitation total, and partially recovered to 1178.68 kg ha⁻¹ in 2025. Similar seasonal responses were observed for plant density at harvest, seed weight per capitulum, thousand grain weight, test weight, and number of seeds per capitulum, whereas oil content remained comparatively stable (45.19–46.88%). Analysis of variance showed significant interannual variation across all evaluated traits, while significant cultivar effects were detected for plant density, number of seeds per capitulum, seed weight per capitulum, thousand grain weight, and seed yield. Partial RDA further detected a significant joint cultivar effect across the eight standardized response traits after conditioning on study year and block (F = 11.49, R² = 0.53, exact p = 0.027). Under the specific environmental conditions observed during the three study years, interannual variation in sunflower performance was substantial; however, annual climatic conditions were not independently replicated and therefore remain confounded with year. Consequently, the observed relationships describe associations within the 2023–2025 site conditions rather than establishing a general causal ranking of climatic and cultivar effects. The results highlight the importance of improving rainfall-use efficiency and integrating cultivar selection with climate-adaptive agronomic management to increase the resilience of sunflower production in water-limited environments.