Medium Yield, Other
This experimental field was in Edmund County, South Dakota. Soybeans were planted in 30-inch rows in strips on June 1, 2021. The purpose of this experiment is to compare the effects of Sugar treatment against no sugar treatment. Sugar was applied in furrow during soybean planting in 80 feet wide strip. This experiment had 3 replications for sugar treatment and 3 replications for no sugar treatment. UAV data was collected using Fix-wing AgEagle UAV with a GoPro sensor (GoPro.com) with 4 band information. To determine the canopy coverage and plant density, the 4-band data was collected during early vegetative crop growth (June 22, 2021) and later growth phase of soybean crop (August 13, 2021) to determine canopy cover. The reflectance differences in the NIR and green bands were used to calculate GNDVI of the field. GNDVI value ranges from -1 to 1. Higher GNDVI values during early growth phase represent higher plant density and higher canopy coverage. Similarly higher GNDVI during later growing phase represent better plant heath and yield. UAV data was collected using Fix-wing AgEagle UAV having GoPro sensor with 4 different band information. To determine the canopy coverage and plant density, UAV data was collected during the early vegetation period i.e., June 22, 2021, and during the later reproductive growth phase of soybean crop i.e., August 13, 2021, to determine if differences could be observed between treatments. NIR band and green band reflectance was used to calculate GNDVI of the field. GNDVI value ranges from -1 to 1. The higher the GNDVI value the greater the plant density and/or canopy coverage.
Overall sugar application decreased yield by 10.7 bu/ac which was statistically significant (Figure 1 & Table 1) with all replicated strips having a lower yield. GNDVI maps did not have differences between treatments during the early vegetative stage of soybean (Table 2). No sugar strips had greater GNDVI values than the sugar strips (Table 3). Did the sugar result in early senecense of the crop and less pod fill? More research at multiple sites with more replications are required to better explain the contrast between two different treatments in different environmental conditions.