BIOMASS PRODUCTION AND MACRONUTRIENTS UPTAKE BY FABA BEAN (VICIA FABA L. ) PLANTS GROWN ON SANDY SOIL IN RESPONSE TO FOLIAR AND FERTIGATION OF BORON AND MAGNESIUM APPLICATION

A pot experiment was conducted using sandy loam soil collected from Quesna, Menoufia Governorate, Egypt, to evaluate the effects of magnesium (Mg) and boron (B) applied through foliar spraying and fertigation on faba bean (Vicia faba L.). Treatments included three levels of Mg (as Mg SO₄) and B (as boric acid), supplied individually and in combination, in addition to a control. Plant growth was assessed at 45 days by measuring fresh matter yield (FMY), dry matter yield (DMY), and macronutrient uptake (N, P, K).The results showed that applying Mg and B, either individually or in combination, significantly increased biomass production and nutrient accumulation compared to the control. The interaction between Mg and B led to an increase in the assimilation of N, P, and K, which in turn improved the growth and yield. The highest combined foliar treatment (B3Mg3) increased N uptake to 143.07 mg pot⁻¹ (relative increase (RI) = 252%), P uptake to 42.08 mg (RI = 231%), and K uptake to 65.75 mg (RI = 241%) at 45 days. Fertigation (B3Mg3) resulted in strong responses, including N uptake of 131.10 mg pot⁻¹ (RI = 213%), P uptake of 40.48 mg pot⁻¹ (RI = 195%), and K uptake of 60.72 mg pot⁻¹ (RI = 203%). The most intensive combined treatments resulted in RI levels exceeding 100%, as FMY and DMY followed a similar pattern. In general, foliar application had a greater impact than fertigation, although both methods significantly enhanced growth and nutrition compared to the control.The study highlights the importance of integrating foliar and fertigation approaches for optimizing Mg and B nutrition in faba bean cultivated on Egyptian sandy soils, offering a pathway to enhance productivity and resource-use efficiency in reclaimed lands.