Abstract
The effect of organic and mineral nitrogen, phosphorus, and bio-fertilizers on growth, yield, and fixed oil content of borage (Borago officinalis L.) and viper's bugloss (Echium vulgare L.) plants were studied in two field experiments. Nitrogen as ammonium nitrate at 0.75 and 110 kg N hectare−1; phosphorus as calcium super-phosphate at 50 and 75 kg P2O5 hectare−1; compost at 1.32 and 2.64 metric tons hectare−1; rhizobacterine + compost at 1.32 ton hectare−1; and phosphorine + compost 1.32 metric tons hectare−1 were used as experimental treatments. The most growth, yield, and fixed oil were recorded with the ammonium nitrate at the 150 kg application rate. Compost mixed with the biofertilizers phosphorine or rhizobacterine produced higher yield than the application of compost only. Chemical analysis of the borage and viper's bugloss plants showed borage oil contained ecosane as a major hydrocarbon (8.62%), and viper's bugloss contained β-sitosterol (9.08%) as the major component in the oil. Each of the species contained γ-linolenic acid with 21.45% for borage and 9.2% for viper's bugloss.