THE IMPACT OF POACEAE UNDERSOWN ON CO2 AND O2 CONCENTRATIONS IN MAIZE (ZEA MAYS L.) CROP

Abstract

The research was conducted in a long-term stationary field experiment, which is located at the Experimental Station of the VMU Academy of Agriculture. The research was conducted in 2024. The long-term field experiment was set up using the field splitting method and was carried out in 4 replications. There were 24 fields in total in the experiment. The initial field size was 18.4 m², the accounting field size was 18 m². The experimental variant fields were arranged randomly. The field protection strip was 0.5 m wide, and the width between the replications was 3 m. In the year of the experiment, the pre-sowing was black fallow. In the year of the experiment, hybrid corn (P7034) was grown with the following undersown from the Poaceae family plants: 1) winter rye, 2) spring barley, 3) annual ryegrass, 4) sowing oats. The studies found that in the fields, due to various unfavorable weather conditions, fluctuations in CO₂ and O₂ led to sluggish plant development and limited the respiration of the plant root system. Throughout the study period, in the upper (from 0 to 10 cm) tested soil layer, the CO₂ concentration was found to be higher by 0.01 to 0.11 percent. units. in the fields with annual ryegrass seeding, compared to the second control fields. After measurements were made at the beginning and end of the crop vegetation, it was found that in the deeper (from 10 to 25 cm) soil layer, the CO₂ concentration was lower (from 0.01 to 0.33 percent. units) in the fields with annual ryegrass seeding, compared to the first control fields. Different seedings had different effects on the soil O₂ content.