Sustainability of the Local Maize (Zea mays L.) Varieties and Populations Cultivation

Within the project “Small-scale grants for biodiversity actors in South-East Europe 2023–2025”, whose main mission is the collection of local varieties and populations, a fundamental question arises: “Why are ‘ancestral’ maize varieties and populations still cultivated?” To answer this question, we conducted a comprehensive set of investigations on 14 maize (Zea mays L.) varieties and populations and on one hybrid, collected from the historical regions of Romania—Transylvania, Moldova, Oltenia and Muntenia. The studies combine quantitative, qualitative and computational methods and focused on energy consumption associated with maize cultivation; maize grain production and related agronomic characteristics; the content of energy macronutrients (protein, fat, starch) and energy elements (CHNS-O, ash, moisture); and nutritional and thermal energy values (upper and lower) of whole cornmeal. The sustainability of the cultivation of local maize varieties was also evaluated based on the energy balance and the energy efficiency ratio. The results demonstrated that the cultivation of “ancestral” maize varieties and populations is sustainable, because the amount of energy obtained, expressed in kJ ha−1, as nutritional energy (24,740,195.04–90,287,743.07), higher heating energy (55,162,983.798–193,374,572.55) and lower heating energy (32,329,465.37–113,906,753.63), is greater than the amount of energy consumed for the establishment and maintenance of these crops (1,742,798.75–19,524,555.05).