L Martínez Calsina1, JV Sáez1, PD Fontana1, M Christina2, A Felipe1, S Zerrizuela1, M Gallac1, S Pérez Gómez1, JI Vallejo3, MM Acreche4 and LE Erazzú5
1INTA, CR Tucumán-Santiago del Estero, EEA Famaillá, Tucumán, Argentina; martinez.luciana@inta.gob.ar
2CIRAD, UPR 115 AIDA, Agropolis, Montpellier, Francia
3INTA, CIAP, IIACS Leales, Tucumán, Argentina
4INTA, CR Salta-Jujuy, EEA Salta, Salta, Argentina
5INTA, CR Tucumán-Santiago del Estero, Tucumán, Argentina
Sugarcane monocropping leads to soil degradation over time, compromising ecosystem services. This work aimed to design an intercropping system of vetch (Vicia villosa-Rizhobium) and sugarcane and assess its yield benefits in comparison to monocropping. Three field experiments were conducted in a dry-subhumid depressed plain in a typical Haplustoll soil. The first and second experiments compared a sugarcane-vetch intercropping system over 2 years. The first experiment evaluated different legume sowing densities (8, 15 and 30 kg/ha), whereas the second experiment evaluated spatial arrangements (number of rows, 62 and 124 rows/ha, and location, 0.8 and 0.2 m distance from row). The third experiment compared monocropping and intercropping combined with and without fertilizer over 3 years in three independent lots of first-ratoon crop. A strip-plot design with three pseudo-replicates per treatment was used for all the experiments. The accumulated rain during the three crop cycles evaluated was lower than the historical mean. The highest aerial biomass of V. villosa at flowering was at 15 and 30 kg/ha sowing density, compared to 8 kg/ha. Additionally, higher aerial biomass was found for 124 versus 62 rows/ha. Sugarcane yield was influenced by the interaction between the cropping system and fertilization, with similar responses found for the first and second evaluated cycles. In the first two cycles, sugarcane yield decreased in the following order: fertilized intercropping > unfertilized intercropping > fertilized monocropping > unfertilized monocropping. For the third evaluated cycle, the driest one, no differences in yield were found for intercropping, with or without fertilization, and both had higher yields than fertilized monocropping, which exceeded the unfertilized monocropping treatment. With an optimized spatial arrangement, V. villosa-sugarcane intercropping systems, whether fertilized or not, demonstrated the potential to outperform conventional monocropping systems in our dry-subhumid areas. Future studies on these systems will explore the other ecosystem services provided by Vicia villlosa.