Zea mays L. popcorn, conv. Everta Sturt, sin. microsperma Körn, is one of the oldest cultivated form which, because of its reduces productivity, is cultivated on reduces surfaces being used for mixed cereals and pop corn. The varieties belonging to this convariety determined by Körn are oryzoides, xanthornis and axyornis of the group with reddish grains, and leucornis, gracillina haematornis and melanornis of the group with rounded coronary part of the grains. No zoned varieties or hybrids are mentioned in the official catalogue of the varieties (hybrids) of Romania, which is why up to this stage only varieties originating from three zones of Romania (Turda, Bărăgan and Jebel), one of Hungary (Kesclemeri) and one of the USA (Little jewels) are studied. The paper contains data referring to sowing period determination for the five biotypes and the results regarding the plant density influence upon the grain yield. The researches were conducted on a typical wet-phreatic chernozem with poor salinization under 100 cm, situated in the Timiş Plain region. The paper presents the results showing the superiority of early sowing, in the first decade of April, when the average yield for the five biotypes was 11% bigger than the yield obtained .When sowing in the last decade of April. Among the biotypes the best has proven to be the Turda biotype, with an average yield for the two sowing periods of more than 4900 kg/ha. The optimal density was of 50.000 harvestable plants/ha. The density increase to 60.000 harvestable plants/ha reduced the yield with 7%, and the density increase to 70.000 plants/ha reduced the yield with 12%. The paper presents the result of the influence the researched factors had on the number of corn cobs per plant, on the percentage of sterile plants and on the grain output.

Zea mays everta Strt – sowing technology

Presentation: oral