Desempenho agronómico de variedades da cultura de milho em diferentes níveis de irrigação e adubação

Abstract

Approximately 90% of Mozambican agriculture is dominated by the family sector, practiced on small plots with low use of inputs and improved technologies, resulting in low yields and limited resilience to climate change. Maize production does not escape this reality; although it is considered the most important crop in the country, it is still predominantly grown under rainfed conditions, with an average yield of 977 kg·ha−1, which is much lower when compared to other countries in sub-Saharan Africa. The present study aimed to evaluate the agronomic performance of maize varieties under different irrigation and fertilization levels. The experiment was conducted at the Agricultural Development Center of Sábie (CEDAS), Eduardo Mondlane University (UEM), from 17 June to 22 December 2024. A randomized complete block design (RCBD) in a factorial arrangement was used, with three factors: irrigation, with two levels: optimal irrigation (100% ETp) and water deficit (30% ETp) applied using a line-source sprinkler system; fertilization, with two levels (fertilized and unfertilized); and three (3) maize varieties: Matuba, SC 419, and MRI 514. The resulting factorial arrangement was 3 × 2 × 2. The evaluated variables included grain yield, above-ground biomass, ear insertion height, plant height, 100-seed weight, harvest index, and leaf area index (LAI). The results showed that water was the most determining factor for all evaluated variables, presenting a significant effect (P < 0.05) across all of them. The highest grain yields and above-ground biomass were obtained under optimal irrigation (100% ETp) and with fertilization. The leaf area index (LAI) showed a strong correlation with plant height and above-ground biomass (R2 = 0.80). The traditional variety Matuba did not show significant differences compared to hybrid varieties in terms of grain yield, harvest index, plant height, and 100-seed weight.