Determination of the effects of urban sewage sludge and boron applications on seedling development and nutritional content of cowpea (Vigna unguiculata L.)

This study was carried out to determine the effects of urban sewage sludge and boron applications on some chemical and physiological properties of cowpea (Vigna unguiculata L.). The experiment was carried out in a factorial pattern with 3 replications according to a randomized plot design. In the study, Karagöz cowpea variety, 4 boron doses (B₀ – 0, B₁ – 50, B₂ – 100, B₃ – 200 mg kg^-1), and 4 sewage sludge doses (SS₀ – 0, SS₁ – 2.5%, SS₂ – 5%, SS₃ – 10%) were used. In the experiment, seedling and root length (cm), seedling and root fresh weight (g), seedling and root dry weight (g), number of leaves (number), leaf area (cm²), and macronutrient elements in the plant were examined. As a result, the effects of sewage sludge and boron applications on seedling and root length, seedling and root fresh weight, leaf number, leaf area, and seedling and root dry weight were found to be significant. In the study, it was determined that the effect of the mutual interaction of the factors on the seedling and root length, seedling and root fresh weight, and root dry weight was significant. In addition, the effects of boron and sewage sludge applications on plant nutrients (P, Ca, K, Mg) were found to be significant. The effect of the interaction of the factors on the elements was found to be significant and the highest phosphorus, calcium, potassium, and magnesium values (1.662 mg kg^-1, 3.159-3.158%, 3.524% and 1.309%) were obtained from B₀xSS₃, B₀xSS₀-B₂xSS₀, B₀xSS₀, B₃xSS₀ applications, respectively, while the lowest values (0.414-0.413 mg kg^-1, 0.454%, 1.361%, and 0.312%) were obtained from B₁xSS₀-B₂xSS₁, B₁xSS₃, B₁xSS₃, B₂xSS₂ applications, respectively.