MINIRHIZOTRON WHEAT ROOT DATA - COMPARISONS TO SOIL CORE ROOT DATA

A nondestructive, quick, and efficient root measurement technique that quantifies root dynamics is critical to understanding environmental effects on rooting. The objective of this study was to compare roots of three cultivars of soft red winter wheat (Triticum aestivum L.) observed in minirhizotrons with those washed from soil cores. Minirhizotron determinations were root count (C(a), count cm-2) and root length (L(a), cm cm-2) per unit area; soil core determinations were root length (L(v), cm cm-3) and root dry Weight (W(v), mg cm-3) per unit volume. Growth stages studied were double ridge, early boot, milk, and soft dough. Analysis of variance showed that growth stage and soil depth were significant for L(v), W(v), C(a), and L(a). Cultivar was significant at early boot and milk growth stages for C(a). Linear regression of L(v), W(v), or L(a) as a function of C(a) provided highly significant slope and, except for W(v), intercept values. Statistically, C(a) was the most discriminating minirhizotron measurement parameter.