Abstract—Soybean (Glycine max L.) is one of the world’s most important sources of high quality proteins and vegetable oils. In Indonesia, soybean is mostly cultivated in dry season, hence prone to the drought stress. Protein and oil content of 19 soybean genotypes were evaluated based on field research which was conducted in dry season (May – August 2015) in Probolinggo, Indonesia. The experiment was carried out in two environments, namely normal environment (plant was irrigated during the growth period), and drought environment (plant was irrigated only up to 40 days after planting). The results showed that variation in protein and oil contents depends on the genotype. Protein content was less sensitive to drought stress at reproductive stage, by an average decrease of 0.59%, whereas the decrease of oil content reached 2.82%. The protein contents of twelve genotypes decreased in normal to stressed environments, from 0.39 to 5.31%; and seven genotypes increased in stressed environments with a range of 0.28 to 7.05%. A similar pattern was shown in oil contents, with a range of decrease from 0.88 to 21.68% in twelve genotypes, and an increase from 0.37 to 5.57% in seven genotypes. Genotype of G511H/Anjs/Anjs///Anjs-3-3 showed a highest consistency of protein content in both of normal and stressed environments, i.e. 42.44% and 42.19%, respectively. Soybean G511H/Anjs/Anjs-5-5 had high oil content (19.71% and 20.08% in the optimal and drought environments, respectively) as well as G511 H/Anj//Anj///Anj////Anjs-6-8 (20.18% and 19.43% in the optimal and drought environments, respectively). Those genotypes identified as early maturing (<80 days) and large seeded-size (>14 g/100 seeds), but with a relatively low yield. Hence, it is recommended to use as gene sources for improvement of oil and protein contents within soybean breeding program in Indonesia.

Index Terms—Drought stress, Glycine max, oil, protein, reproductive stage.

The authors are with Indonesian Legumes and Tuber Crops Research Institute, Jl. Raya Kendalpayak KM 8, PO Box 66 Malang, Indonesia (email: my_ayda@yahoo.com).

Cite: Ayda Krisnawati, M. Muchlish Adie, "Protein and Oil Contents of Several Soybean Genotypes under Normal and Drought Stress Environments at Reproductive Stage," International Journal of Bioscience, Biochemistry and Bioinformatics vol. 7, no. 4, pp. 252-261, 2017.