Wet Agriculture in the Lowlands: Maize Marceña

Core Ideas The milpa marceña is an ancient maize agrosystem on herbaceous wetlands “popals” in the dry season. Three improved maize cultivars and the traditional cultivar mején were evaluated. The mején cultivar showed the highest performance. The milpa marceña is compatible with the hydrological dynamics of wetlands and without the use of industrial inputs. Although herbaceous wetlands are one of the most productive ecosystems and their functions provide benefits to humankind, they have been subjected to a number of disturbances over the past 65 yr. Wetlands have been drained to convert them into permanent agricultural land and urban areas, or used by the oil industry or for construction of hydroelectric dams. Moreover, little has been done to innovate the milpa marceña, an ancient maize (Zea mays L.) agrosystem on herbaceous wetlands dominated by hojilla (Thalia geniculata f. rheumoides) named popals in the dry season (March–June). From an agroecological perspective for improving milpa marceña, in a popal soil (Eutric Molic Gleysol), three improved maize cultivars (CP‐560, CP‐561, and CP‐562) and the traditional cultivar mején were evaluated under three planting densities (50,000, 53,000, and 60,000 plants ha–1) with no use of mineral fertilizers, herbicides, or pesticides. The results show that precipitation during the milpa marceña growth cycle was 50% lower than the amount required for a successful maize crop (>1 Mg ha–1), hence avoiding the risk of flooding. Maize cultivars take groundwater and nutrients from popal soil; however, these results suggest that cultivars were subject to N deficiency and water stress in the flowering stage. We concluded that the mején cultivar showed the highest performance, with 3.3 Mg ha–1, i.e., it has attributes not previously considered (e.g., plant × microbe interactions) in plant breeding programs for drought‐tolerant or flood‐tolerant cultivars. There is a need for further research and conservation on the use of popals.