By Laura Edwards
SDSU Extension State Climatologist
Soybeans are in their moisture-critical reproductive stage. Drought stress during this growth stage can significantly impact yield, so here are some things to look for.
When soybean is drought stressed, the leaves will flip over to show their silvery-green undersides (Figure 1). This is a defensive mechanism they use to reflect more light, reducing the amount of sunlight the plant takes in through its leaves. This also reduces the photosynthetic process, which in turn can affect the growth and productivity of the plant.
Soybean plants will also fold in their leaves to conserve water. Similar to leaf flipping, the plant is minimizing the leaf area that is exposed to the sun to reduce photosynthesis. This drought response can also reduce plant growth and productivity. Both of these drought defense mechanisms can reduce yield by reducing the plants uptake of moisture and converting it to energy.Click here to see more...