Effect of Mineral Fertilization and Some Organic Compounds on Faba Bean Crop in some Soils at the New Valley, Egypt

 
 
FIELD experiments were carried out during two successive years in two sites at the New Valley, Egypt. The first site was clay soil located at El-KaserVillage, El-Dakhlla Oasis and the second site was sandy soil located at El-Monera village, El-Kharaga Oasis. Seeds of faba bean variety Rebaya were cultivated in both the two studied locations. This study was designed in order to improve the yield of faba bean under conditions of the NewValley soils by the combination of mineral fertilizers and some organic compounds. Nitrogen (N), phosphorus (P) and potassium (K) fertilizers were applied as soil and foliar applications at different rates. Different rates of boron (B), molybdenum (Mo) and zinc (Zn) were applied as foliar applications. Some organic compounds viz., humic acid (HA), amino acid (AA), ascorbic acid (AS) and licorice extract (LC) were combined with mineral fertilizers.
 
Application of N, P and K along or with B, Mo and Zn increased yield and nutrient contents of faba bean. The treatments of mineral fertilizers and organic compounds further increased yield components, nutrient contents, total antioxidants activity and total phenol of faba bean in both soils. Organic compounds increased the yield and their effectiveness could be arranged as: LC < HA < AA< AS in ascending order.  Mixing these compounds had higher effect on yield and nutrient contents than individual applications. Their effect could be arranged in ascending order as: LC + HA< LC + HA + AA< AS + AA + HA< AS + AA + HA + LC. The AS had the highest effect on total phenols and antioxidants. The LC had higher values than HA and AA treatments, respectively. The most effective treatment in the yield was (AS + AA + HA + LC + N₂P₂K₂ + with micronutrient), which achieved 5.95 and 2.73 t fed^-1 of shoot and seed, respectively in sandy soil. In clayey soil, these values were 8.91 and 4.30 t fed^-1, respectively. Regarding total antioxidants and phenols, the same treatment could achieve the highest values in both soils recording 216 and 227 μg ascorbic acid ml^-1 extract and 791 and 876 μmol of gallic acid ml^-1 extract for shoot and seed, respectively in sandy soil. These values were 231 and 243 μg ascorbic acid ml^-1 and 891 and 983 μmol of gallic acid ml^-1 in clayey soil, respectively. This study demonstrated that incorporating some organic compounds along with mineral fertilizers has a beneficial effect on yield and quality of faba bean.