Response of Soybean Genotypes to Varied Organic Fertilization Under Greenhouse Conditions

This study investigated the response of three soybean genotypes (Giza 21, Giza 35, and Giza 111) to various organic fertilization treatments under greenhouse conditions. A pot experiment was conducted during the summer of 2022 at the Faculty of Agriculture, Mansoura University, Egypt. Our results revealed significant variations in performance among the tested soybean genotypes across most measured characteristics. Giza 21 consistently outperformed Giza 111 and Giza 35 in root length, shoot, and root fresh weight, number of nodules, and both of fresh and dry nodules and root weights. While Giza 21 and Giza 111 were exhibited comparable performance in shoot length, seedling vigor index, and shoot dry weight. Organic fertilization significantly influenced all evaluated parameters, encompassing field emergence, shoot and root growth, fresh and dry biomass, and nodulation. Among the treatments, vermicompost combined with 6 times application of seaweed generally produced the highest values for these characteristics. Notably, vermicompost + 6 times seaweed and chicken manure + 6 times seaweed treatments showed no significant difference in field emergence. Furthermore, a significant interaction effect was observed between soybean genotypes and organic fertilization for all examined traits. The most favorable results for root length, nodule number, and root and nodule fresh and dry weights were consistently achieved by combining the Giza 21 genotype with the vermicompost + seaweed treatment. This combination represents a valuable approach for improving early plant establishment and nutrient acquisition, which are critical precursors to maximizing soybean productivity. Further validation through field trials and yield assessment is warranted.