About Us | Help Videos | Contact Us | Subscriptions

Proximal sensing can estimate forage sorghum yield


Proximal crop sensing has been used for predicting crop yield, the first step in development of algorithms for sensor-based N management. Most studies were conducted with grain crops, but a recently published article in Agronomy Journal discusses the use of crop sensors for yield prediction of brown midrib dwarf brachytic forage sorghum (Sorghum bicolor L.) in the Northeast.

Sorghum field

The study evaluated the impact of timing, sensor orientation and height of scanning, and the use of Normalized Difference Vegetation Index (NDVI) data versus in-season estimated yield (INSEY = NDVI/days after planting [DAP] or growing degree days [GDD]) on the ability of sensor data to predict yield of forage sorghum harvested at soft dough.

Sensor height and orientation impacted measurements up to 45 days after planting but not once the canopy was fully developed. The most accurate yield predictions were obtained 49 DAP when sorghum was 0.76 m tall. The INSEY expressed as plant growth per day (INSEYDAP) best correlated with yield. The results of the study show that crop sensors can be used to accurately predict forage sorghum yield, but timing of scanning and scanning height and orientation need to be standardized to obtain algorithms that can cover a larger region.

Read the full open access paper in Agronomy Journal