Effect of three live covers (Pueraria phaseoloides, Vigna radiata and Crotalaria juncea) on the plant-soil interface of a clonal plantation of Tectona grandis L.f.

Abstract

[Introduction]: The use of cover crops for weed management is an agroecological strategy that influences physical, biological, and chemical properties of the soil. [Objective]: This study evaluated the effect of three cover crop species in a clonal Tectona grandis plantation in Pocosol, San Carlos, Costa Rica. Three aspects of the agroecosystem were analyzed: weed suppression, development of clonal teak trees, and soil physicochemical properties. [Methodology]: A randomized complete block design with four replications was used. Three cover crop species were established: Pueraria phaseoloides (kudzu), Crotalaria juncea (crotalaria), and Vigna radiata (mung bean). The experiment began in 2021, and in 2024, evaluations were conducted for macro- and micronutrients, soil penetrability, bulk density, soil chromatography, tree growth, and weed cover. [Results]: Increases were observed in carbon, organic matter, pH, and calcium saturation, along with a decrease in acidity saturation, phosphorus, and copper. The combination of V. radiata and C. juncea showed the highest values in tree height and diameter. [Conclusions]: P. phaseoloides was the only cover crop species that remained on-site, effectively controlling weeds. However, proper management during the early years of establishment and determination of the optimal planting density are required.