Initial Aspects of Fine Root Development Patterns in Perennial Ryegrass.

Little is known of the developmental patterns of fine roots (0.09 mm diameter) on perennial ryegrass (Lolium perenne L.) seedlings and tillering plants. We used time-lapse photography techniques with scanners and small aeroponic chambers to survey 48 ryegrass seedling root systems during their first month of development. The plants were then removed, planted into pots, and, after developing 5 or more tillers, broken apart, trimmed, and individual tillers placed back into aeroponic chambers. These tiller plants were recorded for a month of development and these images were then compared to images of their seedling parents. There were extensive differences between seedlings in lateral root development patterns, but little difference between tillers derived from different seedlings. These results suggest significant cryptic selection for uniform shoot-borne lateral fine root developmental patterns, and little for seedling root developmental patterns.