Response of Oil Lettuce to Bio-,mineral Phosphorus Fertilizers and Boron Foliar Application Under Calcareous Soil Conditions

The main purpose of this investigation was to evaluate the growth, yield and quality of oil lettuce under calcareous soil conditions. Two field experiments were carried out at Mariut Experimental Station, Desert Research Center, Egypt, during two successive winter growing seasons 2015/2016 and 2016/2017 to study the effect of four concentrations of boron, control (without boron), 300, 500 and 700 mg/L borax applied as foliar spraying at two times during growth season and assigned in the vertical plots and six treatments of mineral phosphorus and biofertilization; control (without mineral and biofertilization), 15.5 kg P2O5/fed., 31 kg P2O5/fed., biofertilizer, 15.5 kg P2O5/fed. + biofertilizer and 31 kg P2O5/fed. + biofertilizer which occupied the horizontal plots. Obtained results revealed that, all studied characters i.e. plant height, leaf area/plant, leaf area index, 1000 seed weight, seed yield/plant, seed yield/fed., biological yield/fed., straw yield/fed., harvest index, oil percentage, oil yield and crud protein percentage were significantly affected by either boron or mineral phosphorus and biofertilization in the two experimental seasons, except harvest index and crude portion percentage in the first season which were not affected significantly by the two studded factors. The interaction between born concentrations and mineral phosphorus with biofertilization treatments had significant effects on all previous studied traits for both seasons except, harvest index in the first season and crude protein percentage in the two seasons, which were not significantly affected by this interaction in this study.