Assessment of growth and yield components following the application of different biological fertilizers on soybean (Glycine max L.) cultivation

In the present study, the effect of five biological fertilizers [b(1) (control), b(2), b(3), b(4) and b(5)] on the yield and quality properties of the seeds of two well-established in Iran soybean genotypes (Glycine max L. cv. Wlliams and Line No. 17) was examined, in order to evaluate their use as an alternative to chemical fertilizers. An experiment was conducted using a factorial arrangement based on a complete block randomized design with four replications. The results showed that by increasing Growing Degree Days (GDD), the Leaf Area Index (LAI) of cv. Williams was relatively higher than that of Line no. 17, whereas Line no. 17 had significantly more chlorophyll (a, b and total) than that of cv. Williams. The highest and lowest weight measurements of 1000 seeds were recorded when fertilizers b(4) and b(2) were applied. Overall, Line no. 17 had a higher total yield of seeds than that of cv. Williams. The application of fertilizer b(1), b(3) and b(5), resulted in the highest seed protein content. In addition, the highest and lowest measurements of seed oil content for cv. Williams, were recorded when fertilizers b(2) and b(3) were applied. Seeds of Line no. 17 had (a) higher phosphorus and zinc content than of cv. Williams, whereas cv. Williams had (a) higher iron and manganese content than of Line no. 17, regardless of the applied fertilizer. K content of seeds had the highest and lowest mean values when b(3) and b(5) fertilizers were applied, respectively. In conclusion, the implementation of biological fertilizers (especially b(3) and b(4)) could be a useful means for minimizing the chemical inputs during soybean cultivation, allowing at the same time for high yield and high quality products