Waterlogging and intercropping systems: how can they affect the growth and dissolved oxygen in rice and maize

ABSTRACT Rice and maize are common staple foods worldwide. While rice grows in wetlands, maize does not; however, climate changes make it probable; therefore, it is important to learn how radial oxygen losses affect neighboring plants in wetlands. With a new intercropping model in mind, we analyzed the effects of waterlogging and intercropping between rice and maize on dissolved oxygen (DO) and its influence on leaf gas exchange, growth and aerenchyma formation under waterlogging and at field capacity, alone or under intercropping. The experiment was conducted in 2 L pots with sand and commercial substrates. The pots had their water refilled daily to maintain treatment conditions. DO in the substrate was measured weekly, and gas exchange and dark green color index were analyzed at 15 and 30 days after germination. Plants were sampled for morphophysiological analysis at the end of the experiment, and their height, fresh and dry mass of organs were measured. Plant anatomy was evaluated according to the usual procedures of plant microtechnique. Rice and intercropping represented the highest means of DO, while maize represented the lowest means of DO. Aerenchyma proportion increased under waterlogging and intercropping without increasing DO. Maize plants seem to thrive, suggesting that rice is suitable for the intercropping model.