Effect of organic and inorganic fertilizers on insect infestation, yield and seed components of soybean

A field experiment was conducted in North Sinai Governorate, Egypt to evaluate the effect of mixture of cow dung, poultry manure and compost on the yield and quality of soybean. Results revealed that soybean plants were infested with B. tabaci, L. glaycinivorella, N. viridula and S. littoralis. Application of chemical fertilizer gave the highest yield, followed by compost, poultry and cow dung manure as compared to control. All the resulted seeds contained 6 fatty acids, with same lipid profile pattern and oleic acid content. Cow dung showed content of Myristic acid (7.3 mg/g) in soybean seeds while chemical fertilizer produced highest content of linoleic acid (48.52 mg/g). Compost application showed high content of Omega 3-linolenic acid (7.33 mg/g), high content of protein 25% and the highest level of total phenolics content (12894.1 μg/100 g on dry weight basis) in soybean seeds. Poultry manure gave the lowest level of protein (19.6%). Cow dung registered the least content of phenolics (83051 μg/100 g on dry weight basis) in soybean seeds. Thus application of organic fertilizer was effective in recording less insect infestation and gave high yield and quality of soybean seeds safe as human food.