Liliana Panaitescu

Climatic variability and recurrent drought increasingly threaten rainfed sunflower production in south-eastern Europe, highlighting the need for practical adaptation strategies. This study evaluated the effects of two sowing dates, early sowing on 24 March (SD1) and conventional sowing on 14–15 April (SD2), corresponding to the common sowing practice in the region, on sunflower productivity and seed quality during three consecutive growing seasons (2023–2025) under rainfed no-till conditions in the Dobrogea Region of Romania. A randomized complete block design with three replications was used, while all agronomic practices remained identical except for sowing date. Crop performance was assessed through yield, oil content, plant density, plant height, seed weight per capitulum, thousand-grain weight (TGW), test weight, and seed moisture, and data were analyzed using ANOVA, Student’s t-test, Pearson correlation, and redundancy analysis (RDA). Early sowing resulted in higher mean values than conventional sowing, increasing seed yield by 25.4% (1341.65 vs. 1070.20 kg ha⁻¹), oil content from 44.80% to 45.90%, TGW from 47.39 to 53.96 g, test weight from 37.46 to 41.64 kg hL⁻¹, and seed weight per capitulum from 34.45 to 38.72 g. The magnitude of the sowing-date response varied among growing seasons, highlighting the importance of considering naturally occurring interannual variability when interpreting treatment effects. RDA indicated that precipitation showed the strongest association with variation in agronomic performance. Advancing sowing by approximately three weeks was associated with improved crop performance across the three growing seasons, which were characterized by naturally occurring interannual meteorological variability. These findings provide site- and hybrid-specific evidence to inform sowing-date decisions for rainfed no-till sunflower production.

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.

This study evaluated the effects of hybrid, climatic variability, and tillage systems on maize grain quality and antioxidant composition under sprinkler irrigation in South-Eastern Romania during 2023–2025. Three maize hybrids (P0900, P0937, and P1441) and three tillage systems (conventional, minimum, and no-tillage) were investigated under field conditions. Grain quality was assessed using hectoliter weight, protein, starch, and moisture content, while antioxidant composition was assessed using tocopherols and β-carotene. The hybrid was the main factor influencing grain quality and antioxidant composition. P0900 recorded the highest hectoliter weight (74.13 kg hL⁻¹), P1441 showed the highest protein content (9.14% DM), α-tocopherol concentration (9.18 µg g⁻¹ DW), and β-carotene content (4.41 µg g⁻¹ DW), whereas P0937 exhibited the highest starch content (74.39% DM). A strong inverse relationship between protein and starch accumulation was observed (r = −0.84, p < 0.01). Climatic variability significantly affected grain quality, with protein content increasing by 28.9%, grain moisture by 7.1% and hectoliter weight by 1.9% from 2024 to 2025, whereas starch content decreased by 1.6%. Tillage systems had comparatively minor effects, with reduced soil disturbance increasing protein and moisture content while slightly decreasing starch concentration. These findings highlight the dominant role of hybrid selection in determining maize grain quality and antioxidant composition under irrigated conditions.

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.

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

Research Journal of Agricultural Science