Variety effects on cotton yield monitor calibration

Authors: Vories, Earl; JONES, ANDREA - Dow Agro Sciences; MEEKS, CALVIN - University Of Missouri; STEVENS, GENE - University Of Missouri

Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/11/2019
Publication Date: 6/17/2019
Citation: Vories, E.D., Jones, A., Meeks, C., Stevens, G. 2019. Variety effects on cotton yield monitor calibration. Applied Engineering in Agriculture. 35(3):345-354.

Interpretive Summary: While modern grain yield monitors are able to harvest variety and hybrid trials without imposing bias, cotton yield monitors are affected by varietal properties. With planters capable of site-specific planting of multiple varieties, it is essential to better understand cotton yield monitor calibration. ARS and University of Missouri scientists at Portageville, together with two southeast Missouri cotton producers, compared yield monitor-estimated weights and observed weights in on-farm variety trials. Consistent with earlier studies, calibration error varied among the varieties in the studies. Gin turnout and some fiber quality properties were correlated with the error in some studies but none were consistently correlated. Data from additional studies will be collected and analyzed and other factors will be investigated to try and achieve a better understanding of the variety-related properties that affect cotton yield monitor calibration. These findings will allow more reliable on-farm precision agriculture studies to help cotton producers remain competitive while improving their ability to efficiently manage their crop.

Technical Abstract: Cotton (Gossypium hirsutum L.) producers were some of the earliest adopters of practices employing site-specific management and yield monitors are an essential component of those precision agriculture methods. The agreement between measured cotton yields and those estimated with yield monitors must be improved to adequately advance precision agriculture, particularly the site-specific planting of multiple varieties. Six site-years of observations with two yield monitor systems were studied with the objective to compare yield monitor-estimated weights to observed weights in replicated cotton variety trials and investigate factors that could relate to any observed varietal effect. The results supported the findings of earlier research indicating that cotton yield monitor calibration is affected by variety. For the six site-years and three combinations of two site-years, correlations were sometimes observed between calibration errors and turnout or some of the HVI measurements, but no factor was consistently correlated across multiple studies. In one study, none of the included factors was significantly correlated with calibration error, while the HVI properties reflectance (Rd) and leaf were both significantly correlated in three comparisons, which was more than any other factor. Data from additional site-years must be collected and analyzed and other factors investigated to find what variety-related properties affect yield monitor errors and to allow the determination of calibration adjustments based on those factors.