Maize yield under Urochloa ruziziensis intercropping and previous crop nitrogen fertilization

Abstract

Maize intercropping with forage crops and N under no-tillage management have led to discrepant results regarding the impact on crop yield. Therefore, understanding various production systems is necessary to assist producers in decision making.The aim of this experiment was to evaluate whether maize (Zea mays L.) intercropping with Urochloa ruziziensis (R. Germ. and C.M. Evrard) Crins promotes differences in the agronomic performance of maize and if split top-dressing N fertilization in the previous crop (common bean [Phaseolus vulgaris L.]) promotes increase in maize agronomic performance. The experiment was conducted during two agricultural years in southeastern Brazil, with treatments arranged as a split-plot fitted in a randomized block design, with four replications. Main plot was cropping systems (two systems -maize sole and maize intercropped with U. ruziziensis) while subplots comprised 10 combinations of split top-dressed N applications, totaling 90 kg ha −1 , applied to the previously cultivated common bean crop. Regardless of the agricultural year, intercropping with U. ruziziensis sown simultaneously with maize reduced maize yield by 12% on average. Intercropping maize and U. ruziziensis increased soil coverage from an average of 64-100% over maize as an only crop. The agronomic performance of maize grown in sole crop or intercropped with U. ruziziensis was not influenced by the effect of top-dressing N fertilization applied in common bean under no-tillage as previous crop. Intercropping maize with U. ruziziensis is a viable option for producers seeking improved soil coverage or grazing opportunities, however, caution is needed since maize yields may be reduced.

Do the intercropping with Crotalaria spectabilis and Urochloa ruziziensis reduce the maize agronomic performance?

“…Therefore, studies on different production environments, soil types, intercropping models, plant arrangements and crop seasons are needed to base more reliable recommendations. Mingotte et al (2021) found that intercropping maize with U. ruziziensis with simultaneous sowing of the two species decreases the maize yield in up to 12 %, similarly to what was observed by Arf et al (2018). In addition, Crusciol et al (2013) concluded that intercropping maize with U. brizantha decreases the maize yield.…”

“…Focused on sustainability, the use of intercrops is a way of integrating financial return and soil protection (Mingotte et al 2021). Thus, the present study shows that maize intercropping systems are viable, and may possibly be part of crop-livestock integration systems, since there are no decreases in grain yield, when compared to single maize crops.…”

“…In situations of scarcity of vital elements to plants, it supplies reserves immediately to the drains, decreasing the concentration of these substances in the culm, resulting in smaller diameters, as observed by and Mingotte et al (2021), when comparing single maize crops to intercropping systems with U. ruziziensis.…”

“…Agropec. Trop., Goiânia, v. 52, e70513, 2022 Most areas with intercropping systems in the world involve maize crops, because one of the requirements for the successful implementation of intercropping systems is that the species used for soil cover or as green fertilizer do not interfere negatively with the agronomic performance of the main species or species of direct economic interest (Crusciol et al 2013, Arf et al 2018, Mingotte et al 2021.…”

“…They generate benefits such as the possibility of implementation of croplivestock integration systems, result in a higher nitrogen (N) availability for the maize crop, and satisfactory straw production for the implementation and maintenance of a quality no-tillage system. However, the intercropping species may generate competition with the maize crop for water, light and nutrients, decreasing the maize agronomic performance (Borghi & Crusciol 2007, Crusciol et al 2013, Mingotte et al 2021. Therefore, studies on different production environments, soil types, intercropping models, plant arrangements and crop seasons are needed to base more reliable recommendations.…”