Influence of Plant Densities on Seed Production in Some Parental Inbred Lines of Turda Maize Hybrids

The sowing density of the parental inbred lines of maize hybrids shoud be chosen in such a way as to obtain the maximum seed yield without affecting the quality of the seed. Based on the data published in other articles on the production of hybrid maize seed, it is considered that for parental inbred lines, optimum density is in the range of 50-80000 plants/ha, while for parental single hybrids between 40-60000 plants/ha. Sowing density is conditioned both by environmental factors as well as suitability of parental forms to different densities. The present study was carried out in 2015 to 2017, at the ARDS Turda, to investigate the impact of three plant densities on behavior of five parental inbred lines of maize hybrids. The obtained results indicated that increasing the plant density (≥70000 plants/ha) determined the increase of the seed yield (kg/ha) for all genotypes. Although several production characters were reduced by increasing density, this decrease did not influence the level of yield, because it was compensated by higher number of plants per unit area. Parental forms TA 452 and TA 447 were identified as the most stable at changing the sowing density, while the lines TC 344 and TA 426 were sensitive to the increase of the plant density, with negative effects on the quality of the seeds.