Identification of Soybean Lines with Traits That Contribute to Drought Tolerance at Planting.

Drought occurring during soybean planting time is common in many areas of the United States. Planting period is one of the most drought-sensitive stages of a soybean crop. A drastically poor emergence will result from seeds remaining in the soil for ≥12 days after having imbibed water, but not having enough moisture to allow radicle elongation. The objective of our study was to identify soybean lines with traits contributing to better emergence percentage at low soil moisture conditions, and thus, drought tolerance at planting. We evaluated a soybean germplasm of 373 lines for (i) amount of moisture needed for germination, (ii) time to produce a radicle, (iii) primary root length, and (iv) seed size to identify (a) lines that require less amount of moisture for germination, (b) lines that quickly produce a radicle, and (c) lines with increased primary root length and to determine (d) whether any relationship exists between seed size and germination percentage. The experimental design was a completely randomized design with five replications. This study is currently underway. The study will identify soybean lines with drought tolerance at planting.