Protein and Oil Content in the Grain Composition of Soybean Varieties
Keywords:
Soybean, Variety, Protein, Oil, Term, StandardAbstract
Soybean is a strategic agricultural crop due to its high protein and oil content, which play an essential role in human nutrition and industrial production. The quality of soybean grain, particularly protein and oil composition, is influenced by agronomic factors such as sowing dates and seeding rates. However, the optimal combination of sowing time and seeding rate for maximizing these quality indicators in newly developed soybean varieties remains insufficiently clarified. This study aimed to determine the effect of sowing dates and seeding rates on protein and oil content in soybean grain. The findings showed that early sowing (April 25–30) at a rate of 60 kg/ha resulted in the highest protein and oil content in both “Madad” (38.9% protein, 19.8% oil) and “Sevinch” (37.3% protein, 18.7% oil) varieties, while delayed sowing and lower or higher seeding rates led to a decrease in these indicators. A consistent pattern was observed across all experimental variants, where deviations from the optimal seeding rate reduced both protein and oil content. The study identifies a clear quantitative relationship between sowing timing, seeding rate, and grain quality parameters for specific soybean varieties. These results suggest that adopting early sowing with an optimal seeding rate of 60 kg/ha is essential for achieving higher protein and oil content, thereby improving the economic and nutritional value of soybean production.
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