Recent Advances in Stalk Lodging Research.

Approaching the problem of stalk lodging from a structural engineering perspective can provide unique insights and produce new methodologies for addressing stalk lodging.

For example, a new field deployable device to non-destructively predict stalk lodging propensity has been developed based on engineering principles. The device has been validated in experimental field trials on maize and sorghum and is able to statistically distinguish stalk strength among elite varieties. It can be deployed by a single user and process approximately 300 to 400 stalks an hour. Monsanto is currently using the device and evaluating its utility in breeding trials. Recent improvements to the device include a graphical user interface, addition of temperature, humidity, and GPS sensors, and improved device ergonomics.

In addition, CT-scans, engineering finite element models, mechanical three point bending tests and compositional analysis of sorghum stalks have demonstrated the dominating effect of stalk geometry on stalk strength. In particular, it has been shown that stalk geometry is able to predict up to 90% of the observed variation in stalk strength, whereas stalk composition (e.g., lignin, cellulose, etc.) is only able to predict up to 20% of the variation in stalk strength. This new finding suggests the need for increased studies investigating the effects of stalk morphology and geometric stress concentrations on stalk strength.