Investigating the Production Potential of Soybean Cultivars Tolerant to Heat Stress from Brazil in Khuzestan Province

Khuzestan province has good potential for oilseed crops production, such as soybeans. At present, however, there are no suitable soybean cultivars in the country that can tolerate the hot conditions of this province well. Therefore, Gelareh Kalhor Agriculture Company, in coordination with the Ministry of Agriculture Jihad, has imported four soybean cultivars (BRS391, BRS232, BRS511, and BRS284) from Brazil. This study aimed to compare the yield of imported soybean cultivars tolerant to heat stress with common cultivars in the country (Rahmat, Caspian, and SK-93) in Dezful climate conditions. The experiment was performed in 2021 in a randomized complete block design with three replications. Results of the analysis of variance showed that soybean cultivars had significant effects on the number of branches per plant, pod production per plant, seeds per pod, 1000-seed weight, and seed yield. But, there was no statistically significant difference among the cultivars studied for seed oil and protein contents. The results showed that imported soybean cultivars were able to produce about 25% more pods per plant, 21% more seeds per pod, and 8% higher seed weight, and in total, 20% higher seed yield than common cultivars. Conversely, the potential for branching in common soybean cultivars in the country was about 33% higher than that of the imported cultivars from Brazil. Among the cultivars imported, BRS232 and BRS284 with seed yields of 2793 and 2697 kg ha-1, respectively, showed higher production potential than the other two cultivars.