title: Correlations between various characters of inbred strains of corn and the relationship between inbred strains and their hybrids tested at three different ecological locations.
abstract: 1. The different reactions of inbred strains and hybrids often influence yield performance under different ecological conditions. Because of the negative correlation between length of vegetation period and yield of the hybrids (r=-0.473) it was possible in some cases to obtain higher yields in a shorter vegetation period up to tasseling and silking. In kernel yield, the relationship between inbred strains and their hybrids was small. Here, specific combining ability is much more important, and length of vegetation period did not show any apparent direct influence. Only in cases of a combination of both high-yielding performance and appropriate day length and temperature could high yields be obtained under corresponding climatic conditions. 2. Dry matter content in kernels at harvest time was distinctly influenced by length of vegetation period (r=0.639 for inbred strains and r=0.767 for hybrids). Correlation between strains and hybrids in dry matter content of kernels was not very close (r=0.335). 3. Grain yield was much more influenced by the number of kernels per plant in inbred strains (r=0.572) than in hybrids (r=0.338), but there was no dependence of the number of kernels per plant on length of vegetation period. The number of kernels was much more influenced by the number of rows per ear (r=0.761 for inbred strains and 0.531 for hybrids), by diameter of ear (r= 0.672 and r=0.414) and by length of ear (r=0.684 and 0.657) respectively. For these characteristics the correlation between inbred strains and hybrids was distinct for length of ear (r=0.537) and number of kernels per plant (r=0.384) only. Some strains, however, did show a closer correlation in these characteristics. 4. Yield is influenced quite clearly by TKW as well (r=0.546 for inbred strains and 0.703 hybrids). There was no relationship between the other tested characters and TKW. The inheritance of these characters between inbred strains and hybrids was quite clear, especially for Cr Mi (r=0.808). 5. Cob percentage (in % d.m. of the whole ear) was only weakly inherited by some of the lines, for example, F 2. Between kernel yield and cob percentage, a negative correlation with r=-0.542 for the inbred strains and r=-0.307 for the hybrids could be found.
authors.affiliation: Angewandte Biologie und Umweltsicherung, Justus-Liebig-University, Giessen, Federal Republic of Germany.
authors.forename: W
authors.initials: W
authors.lastname: Schuster
authors.forename: Z
authors.initials: Z
authors.lastname: Cernjul
authors.forename: U
authors.initials: U
authors.lastname: Posselt