Linkage between tolerance to high soil acidity and genetically high protein content in the kernel of wheat,Triticum aestivum L. and its possible use in breeding

Summary The winter wheat variety Atlas 66 has both the characteristics high protein content in the kernel and tolerance to high soil acidity. In a group of 121 F₄ lines, all derived from crosses with Atlas 66, a correlation coefficient of 0.39 was found between the two traits. A comparable group of 49 advanced generation lines, reselected for high protein content behaved similar, with a correlation coefficient of 0.37.The frequency distribution over the different categories of tolerance to soil acidity was tested within F₃ and F₄ populations of each two crosses between an Atlas 66-derived high-protein selection and a HRWW-variety. Both crosses slightly differed in frequency distribution but there were no differences between F₃ and F₄ distribution curves of one cross combination.Samples of varieties were tested, each sample having a phenotypically different protein content. The results indicated that protein content per se did not influence the level of tolerance to soil acidity. So it is concluded that although the two characteristics are genetically different they are linked to a certain extent.Individual regression lines were calculated for separate groups of F₄ selections derived from one cross combination. Two groups deviated from the majority and general pattern in that they showed a negative correlation between high protein and better tolerance. One of them differed significantly. A hypothesis is suggested to explain these exceptions.It is possible to screen lines for tolerance to high soil acidity in order to select within segregating populations for high protein content in the kernel, provided that positive selection is applied and that one of the parents combines both characteristics.