THE INFLUENCE OF SOWING DENSITY ON CERTAIN PLANT AND COB CHARACTERS ON SOME EARLY MAIZE ( ZEA MAYS L. ) HYBRIDS PUBLISHEDEmilia TINCA, Ana COPÂNDEAN, Voichița V. HAȘ, Roxana E. CĂLUGĂR, A. VARGA, AB. GHEȚE, CG. BĂLAȘ-BACONSCHI, I. HAȘ
In the 2014-2015 years there were studied eight early maize hybrids (Zea mays L.), which were coming from ARDS Turda, and the research goal was to establish interactions between sowing density and certain characters, such as leaf length and width (leaf area) at the main cob insertion, and also cobs length and weight. It is known that leaves above the first cob are primarily considered the "kitchen plant" in the sense that it provides the necessary nutrients for cobs development.Therefore it is important to know, and that represents the stage of the research, whether there are differences between different sowing densities on these characters, and if this are manifested to all studied genotypes. The study was carried out on breeding fields, at three culture densities: first density- 40.000 plants/ha, second density- 60.000 plants/ha and third density- 80.000 plants/ha.Method of settlement of the experience was randomized block, consisting of two experimental years, eight experimental variants and two repetitions. Cob weight is a component of production which is directly correlated with production, therefore knowledge of the sowing density that influenced positively this character, is important and helpful in the process of maize improvement.The research degree of novelty is represent by studying the most recents eight hybrids omologated on ARDS Turda, under low and high densities. In both experimetal years positive correlations were identified for most variants, between sowing density 1 and 2, and the leaf lenght and width of the main cob insertion. Turda 332 hybrid was significantly positive influenced by the sowing densities of 40,000 and 80,000 pl / ha in terms of leaf area. The first and second sowing densities, had a significantly negative influence for this character for Turda 248 hybrid.Turda 248 hybrid was very significantly positive influenced for both weight and length of the cob and its distinct significantly positive influenced for kernel depth.Turda 332 and Marius TD hybrids were also distinctly positive significantly influenced for the cobs weight and kernel depth. Despite heat during pollination in 2015, affected the foliage of the plants, in the case of three early maize hybrids, were registered increased values of the studied vegetative characters. Although the two experimental years were different in terms of environmental conditions, 2014 year has proven to be favorable to maize crop, there can be detached some conclusions on the topic addressed: of the eight studied hybrids at the 3 sowing densities only 3 hybrids were noted: Turda 332, Turda 248 and Turda Favorit for cobs characters, and two hybrids: Turda 332 and Turda 248 for plants characters.
sowing densities, early maize hybrids, cob weight, leaf area