Genetius

A comprehensive multi‑environment trial of 437 maize testcross hybrids derived from 38 MLN‑tolerant lines and 29 testers identified additive genetic effects as the primary driver of grain yield, disease resistance, and drought tolerance. Strong general combining ability and specific combining ability patterns were uncovered, with top hybrids delivering up to 5.75 t ha⁻¹ under MLN pressure while maintaining high performance under optimum and drought conditions. The study provides a framework for selecting elite parents and exploiting both additive and non‑additive effects to develop resilient maize hybrids for sub‑Saharan Africa.

The study evaluated double‑mutant hybrid maize (W22/B73) lacking miR394‑regulated genes ZmLCR1 and ZmLCR2 and found enhanced drought tolerance, marked by increased epicuticular wax, reduced ROS, and unchanged membrane damage. Under field rain‑fed conditions, the mutants maintained normal flowering and nutritional quality while delivering higher ear weight and kernel number compared with wild‑type hybrids.