Genetic analysis of root growth in wheat

Abstract

SUMMARY The growth characteristics of root systems were studied in the wheat varieties Chinese Spring' Hope and the chromosome substitution lines of Hope into Chinese Spring. The growth patterns varied considerably between the lines and this was due to the fact that the plants formed different numbers of tillers and grew for different periods of time. A correlation existed between the development of the shoot and root systems although some lines differed widely in their shoot root ratios. Differences between the lines in the early stages of growth were small and they reacted uniformly to different levels of phosphorus supply. The relation between shoot and root growth was also shown by the fact that the conclusions from genetical analyses were very similar. These showed that the method of control was largely additive in nature. It was concluded that variations in shoot and root characteristics were markedly influenced by single genes affecting the duration of the vegetative growth period as well as by polygenic systems.