Speaker
Description
In recent decades, forage production systems have become more concerned about the effects of global climate change on animal feed. Choosing forage species that thrive in adverse conditions and adopting sustainable management methods, such as intercropping, are crucial aspects in building resilient systems. Self-seeding annual legumes can benefit low-input systems by providing forage and abundant seeds in the next season. The soil seed bank, primarily composed of hard seeds acts as a crucial reserve, ensuring pasture regeneration during harsh winters or growth disturbances (Ley farming). Medicago intertexta L., or Calvary medick, is a relatively underexplored annual self-seeding plant that could be significant in these systems. In semi-arid areas of the Mediterranean, incorporating this species into forage systems can have beneficial effects on livestock production, nutritional quality, nitrogen fixation, and soil fertility. This is achieved by maintaining soil organic matter and enhancing soil structure. Despite these favorable factors and its widespread wild distribution in the Mediterranean region, the practical utilization and diffusion of this species in agricultural systems are currently hindered by a lack of scientific knowledge regarding its agronomic management. This study aimed to evaluate the forage production performance of M. intertexta in both pure stands and mixed cropping systems, simulating various utilization and management methods.
Field experiment was conducted during the 2023-2024 growing season at the experimental farm "Carboj" (Department of Agricultural, Food and Forest Sciences, University of Palermo, Castelvetrano, Trapani, Italy). The experiment was set up in a split-plot design with four replications. The main plots consisted of Calvary medick (M. intertexta), ryegrass (Lolium multiflorum), berseem clover (Trifolium alexandrinum) in pure stands, and their mixtures arranged in alternating rows, adopting a substitutive intercropping design. Sub-plot treatments included five different utilization methods:
(1) High-intensity utilization: first cut at 100 days after sowing at 3 cm and subsequent cuts at 35-day intervals.
(2) Low-intensity utilization: first cut at 100 days after sowing at 8 cm and subsequent cuts at 35-day intervals.
(3) Double high-intensity utilization: first cut at 100 days after sowing at 3 cm and subsequent hay production.
(4) Double low-intensity utilization: first cut at 100 days after sowing at 8 cm and subsequent hay production.
(5) Only one cut at the flowering moment for hay production.
For M. intertexta, the intercropping with ryegrass showed significant benefits. Under high-intensity cutting, this combination was advantageous for the yield of M. intertexta but also for ryegrass. The intercropping with Trifolium alexandrinum still provided a superior yield compared to pure stands. Under low-intensity conditions, pure M. intertexta had the highest yield, but the difference with intercropping with ryegrass was not significant. For hay production, intercropping with ryegrass offered a significantly higher yield than pure M. intertexta and intercropping with Trifolium alexandrinum. Thus, intercropping with ryegrass seems to be the best strategy to enhance the productivity of M. intertexta, especially for hay production.
