Project Summary:
Drought remains a major challenge, frequently limiting soybean yields across Minnesota. Even in high-productivity regions or fields, farmers often identify areas suffering severe water stress due to variations in soil texture, landscape position, and seasonal weather. These drought-prone areas reduce field productivity and drag the profitability of the entire field, contributing to significant financial losses.

While advancements in soybean varieties have increased yield potential, most variety trials focus on mid- or high-productivity areas, leaving a gap in knowledge for low-productivity, drought-prone conditions. As a result, farmers often select varieties based on yield potential alone, with limited consideration of their differential ability to tolerate water stress. This approach may lead to missed opportunities for increasing use efficiency of the other inputs and improved returns in more challenging environments.

This project aims to evaluate whether elite soybean cultivars differ intrinsically in their ability to tolerate water stress and quantify the economic value of these differences. By providing farmers with decision-making tools, the project seeks to: 1) Increase yields under stress, by helping farmers identify varieties that perform better and maximize yield under drought conditions. And 2) Reduce risk: Enhance yield stability in soybean performance across different environmental conditions, ensuring more predictable outcomes, reducing wasted input costs in low-productivity areas that are usually managed as the entire field.
Ultimately, this research orientates farmers in cultivar selection, increasing overall farm profitability and stability for soybean production in Minnesota.

Project Objectives:
1- Evaluate whether elite soybean cultivars differ intrinsically in their ability to tolerate water stress.
2- Quantify the economic value of these differences.

Project Methodology:
Field experiments:
Field experiments are going to be conducted at St. Paul campus and at Becker experimental station. Each experiment will be located in an even soil area with a reduced water holding capacity that ensures the occurrence of water stress in the absence of irrigation. Eight adapted commercial elite varieties (MR 1.7-2.) selected based on different seed companies’ recommendations are going to be planted in plots 20 feet wide and 30 feet long under a complete randomized block design. At St. Paul campus the experiment will be conducted under completely rainfed conditions. At Beker, the experiment will count with three faces: 1-water stress until R3, 2-water stress after R3, and 3-a control without stress. Nutrient, weeds, pathogens and pests will not limit crop yield in any treatment in any experiment.

Field Measurements:
Development: weekly.
Radiation interception: bi-weekly
Soil water content: bi-weekly
Water balance: daily bases.
Biomass accumulation at R1, R4 and R7.
Yield and yield components.

1- Evaluate whether elite soybean cultivars differ intrinsically in their ability to tolerate water stress.
2- Quantify the economic value of these differences.

Comprehensive evaluation of stress tolerance among elite soybean varieties:
Quantification of the value of differences of drought tolerance among commercially available elite soybean cultivars. Breakdown of the effects on crop development, radiation interception, water balance, biomass accumulation, yield, and yield components.
Practical recommendations for soybean variety selection tailored to low-productivity areas with recurring water stress issues that will be oriented to increase yield and yield stability.
Extension resources: Extension publications, workshop materials, and decision-support tools, to help farmers implement project findings effectively.

This project directly addresses a generalized issue for Minnesota soybean farms: drought-prone areas and drought generated yield losses. By identifying elite varieties with superior drought tolerance, growers could increase yield bottom line, overall yield and yield stability for their systems. Growers will benefit from reducing the risk of yield fluctuations associated with drought-prone fields and areas.