Table 1.

Comparison of stalk mechanical phenotyping devices.

Device	Crop	Measurement	Pros	Cons
Berry’s device a	Wheat (multiple plants at once)	Stem failure strength Root failure strength (with soil wetting)	Inexpensive Adjustable push‐bar height Digital force‐torque display Rapid measurements (6 min/plot)	Unable to measure individual plant properties Heavy battery pack Results dependent on soil conditions
Stalker b	Wheat, oat, barley	Resistance force	Open source Nondestructive Field‐portable Can test singular or multiple plants LED indicates maximum rotation at 45° Data stored on SD card Continuous force‐displacement data collection	No digital display Before data analysis, load values must be converted to newtons (N) using a calibration curve Only used for small grains Operator‐dependent data (prone to jitter)
Guo’s device c	Maize	Pulling force Equivalent force	Nondestructive Portable Digital display Data stored in flash memory Flexible pulling directions	Difficult to translate measurement to engineering principles Operator‐dependent data (prone to jitter)
DARLING d	Maize, sorghum	Failure strength Flexural stiffness	Replicates natural failure patterns Field‐portable Rapid measurements (17 s/test) Can be nondestructive Adjustable load cell Graphical user interface Continuous force‐displacement data collection	Only useful for large grains Accuracy of measurements decreases as rotation increases past 20° Dependent on soil conditions Operator‐dependent data (prone to jitter)

^aBerry et al. (2003b).

^bHeuschele et al. (2019).

^cGuo et al. (2018, 2019).

^dCook et al. (2019).