Measurement of Canopy and Ear Temperature in Maize: A Methodology for Determining Grain Filling Period

Each digital sensor was positioned within its respective shelter at the center of each plot. The GSP-6 sensor was affixed to the upper ear leaf in the middle of each plot, hanging vertically from the ground at a height of approximately 150 cm. Table 1 presents the recorded canopy temperature. Ear temperature was measured using a Yaxin-0233 tool based on thermal techniques (Beijing Yaxin Technology Co., Ltd., Beijing, China) between 12:30 and 1:30 pm. Ten ears were measured in each replication at DAS 85 in 2019 and at 5-7 day intervals throughout the grain filling period in 2020. The corn bract leaf was punctured with the probe, which was then inserted into the middle ear level to measure the temperature.