THE INFLUENCE OF NITROGEN AND RHIZOBIUM APPLICATıON ON FATTY ACID COMPOSITION OF SOYBEAN [GLYCINE MAX (L.) MERR.]

Abstract

The content of soybean seeds can vary widely and is influenced by the environment and management techniques. An experiment was conducted in Siirt province of Turkey in 2019 to investigate the influences of Rhizobium japonicum under various fertilizer nitrogen doses on the fatty acid composition of soybean variety Gapsoy-16 soybean. The experimentation was arranged in split plot design with five different nitrogen doses (0 kg/ha, 50 kg/ha, 100 kg/ha, 150 kg/ha, and 200 kg/ha in pure form) as main plots treatments and Rhizobium inoculation (with or without bacteria) as the sub-plot treatments. Results showed that higher nitrogen dosage (200 kg/ha) with and without rhizobium inoculation reduced linoleic and linolenic acids contents but increased oil ratio, oleic, arachidic, stearic and palmitic acids contents of soybean seeds. The determined content of oil ratio, oleic acid (C18:1), linoleic acid (C18:2), linolenic acid (C18:3), arachidic acid (C20), stearic acid (C18) and palmitic acid (C16) were between 14,8-19,03%; 29,73-31,36%; 31,16-33,06%; 7,32-7,82%; 1,33-1,51%; 3,52-3,86% and 14,91-15,78%, respectively. Rhizobium inoculation increased the oil ratio without nitrogen (N1=0 kg N/ha) and with adding 200 kg N/ha (N5) dosage, whereas it reduced the ratio at other N doses