The Role of Green Manures on Weed Control and Sunflower Production on the Poorly Fertile Soils

The cultivation of acidic soils presents a major challenge for agriculture, as it obstructs crops productivity due to mineral toxicity, nutrient deficiency, and poor water uptake. The identification of new methods to improve the agricultural properties of the poorly productive acidic soils requires the development of research to increase quantitative and qualitative of production. Organic fertilizers can ameliorate soil quality. The aim of this study was to investigate how different green manures influence quantity and quality of production, as well as weed control of the sunflower crop under acidic soil conditions. The research was conducted in 2023 and 2024 on an albic luvisol in northwestern Romania (Livada, Satu Mare County), using various plants as green manure and evaluating their effects individually and in interaction with chemical fertilizers to increase sunflower crop yields. The experiments were set up at the Livada Agricultural Research and Development Station using the split-plot method with two factors: Factor A - green manure with six levels (sunflower, triticale, soybean, pea, rapeseed, and control) and Factor B - two levels (chemical fertilization and no chemical fertilization). Results indicated that highest number of weeds/sqm was recorded on the plot with peas as green manure with 46% higher that the control. Also results show that the level of dicotyledonous weed infestation was reduced by 32% by using green manures. As for the sunflower yield, there was clearly a positive result especially on the plots with peas as green manure, with 1036 kg/ha over the control unit, without green manure. As a conclusion we can declare that on the poorly fertile and acidic soils from the region, green manures had a clear benefic effect on the sunflower crop, from both the weed infestation and the crop production aspects.