In the maize breeding the local landraces could presented a special interest, evenly like useful gene sources for adapting capacity and for physiological and agronomical traits and for valuable quality. The exploration of these resources can be possible only through complexes studies and measures which will determine the biodiversity keeping and the sustainable use of this. The creation of maize hybrids which, among other features, to be early it is a big concern of breeder teams. In northern and pre-montane areas, due to thermal lowered resources, precocity is indispensable to achieving maturity. The objectives of this research were: -to explore the phenotypic variability existing for early maturity in a large range of maize local and synthetic populations; -to identify genotypes that could be interesting in heritability of short growing season. It was noticed some maize local populations which can be used like initial genetic material for breeding of precocity, such as: Avram Iancu, Bereni, Corbu 189-84, Cerbal, Dumbravita, Desesti, Mara1, Mara2, Eremitu, Giulesti, Satu Lung, Satu Mare, Tarna Mare, Vlaha, and synthetic populations Tu Syn. 6, Tu Syn Mara1, Tu Syn Gutin, Tu SRR 2I(5D), Myn Syn AS-G, Carnota Composite. The highest values of additive effects for grain dry matter content were recorded at: Tu Syn Mara (ĝ n = +1.80), Tu SRR 5D (2I) (1) (ĝ n = +0.62) and Tu Syn 1 (ĝ n = +0.45). Therefore, Tu Syn Mara, Tu SRR 5D (2I)(1) and Tu Syn 1 produced hybrids with the most early maturity.

maize germplasm, precocity, GCA, general combining ability; SCA, specific combining ability

Presentation: oral