Current and future agronomic perspectives on rainfed soybean production systems in South Africa

Abstract

AbstractAlternative crop and soil management practices can offer additional tools to address current soybean [Glycine max (L.) Merr.] yield gaps in South Africa. Despite recent genetic advancements and the introduction of novel weed management strategies, soybean yield remained static. Inconsistent rainfall patterns, high temperatures, and soil compaction have been limiting soybean productivity. Uncertainty exists among farmers regarding optimal nitrogen fertilizer management due to inconsistent yield responses and likely due to a shortage of locally generated scientific information. The benefits provided by including soybean in a maize (Zea mays L.) monoculture production system has been identified, however, crop rotation effects on yield in combination with newly introduced agronomic practices such as no‐tillage and crop residue retention are inconsistent. Modern germplasm offers several opportunities to improve water use efficiency by limiting water‐stress conditions during the reproductive growth stages when yield components are highly sensitive. The introduction of less rigorous soil tillage practices alongside greater residue retention can lessen surface runoff and evaporation losses. Scientifically evaluated research is crucially needed to advance the understanding of current soybean yield gaps and to facilitate the development of tailored management practices to address farm‐specific challenges while beneficial soil and crop conditions are taken advantage of.