Grain moisture dynamics in maize lines belonging to different ripeness groups during ripening

Abstract

Purpose. To study the dynamics of moisture-yielding ability in maize lines belonging to different ripeness groups during different phases of development by laboratory thermostatic-weight method and field method using an AVD 6100 needle hydrometer.Materials and methods. The study was carried out in the crop rotation fields of thePlant ProductionInstitute of named after V.Ya. Yuriev of NAAS in 2017–2019. One hundred self-pollinated maize lines belonging to different ripeness groups were investigated.The water content in grain was determined by two methods: a laboratory thermostat-weight method and a field method using an AVD 6100 needle hygrometer modified to measure the water content in maize grain. The water content in grain was evaluated every ten days in two replications (on days 30, 40, 50 and 60 days after pollination).Results and discussion. The three-year study of the grain moisture dynamics showed that mid-late accessions had the highest moisture content in grain at all sampling timepoints. On day 60 of sampling, the lowest moisture content in grain was observed in mid-early lines: in 2017 – 13.9%; in 2018 - 15.0%; and in 2019 – 19.7%.Analyzing the intensity of moisture loss by grain of maize lines of different ripeness groups, we found that on days 30–40 day of sampling from mid-early lines this parameter was almost the same in the 3 years, however, on days 40–50 in2017 the moisture loss was minimal (0.6%), and in 2018, on the contrary, – maximum (1.7%). On days 50–60 in2017, on the contrary, the moisture loss intensified, and in 2018 it slowly came down to 0.1%. In 2019, there were no sharp fluctuations in the moisture loss intensity, and the values were almost at the same.Conclusions. In each ripeness group, we singled out lines with a low percentage of grain moisture, and this allows selecting maize lines with a good moisture-yielding ability. It was established that the intensity of moisture loss by grain of the maize lines differed, and in each of the three ripeness groups, lines with the maximum moisture loss per day were distinguished.To compare the results on the moisture content in grain obtained by laboratory thermostat-weight method and field method using the AVD 6100 needle hygrometer, correlation analysis was performed. It was found that the results of the laboratory thermostat-weight method and the field method using the AVD 6100 needle hygrometer completely coincided for two test years. This allows using needle hygrometers to determine the moisture content in maize grain, which greatly facilitates and speeds up work and shortens the test period.