Root Growth of Green Pea (Pisum sativum L.) Genotypes

Abstract

Root development of 12 genotypes of green pea was followed using a minirhizotron system. Rooting‐depth development followed a simple pattern, consisting of an initial lag phase during germination and early growth, followed by a linear phase that ended ≈10 d after the onset of flowering. All genotypes followed this general pattern. Significant differences were found in the length of the linear phase of rooting‐depth development. These differences were due to variation in the length of the initial lag phase, and variation in the time until the onset of flowering. The genotypes with the lowest seed weight also showed the longest lag phase. No significant differences in the rate of rooting‐depth development during the linear growth phase were found among the genotypes. The rate of rooting‐depth development was estimated to be 0.086 cm d−1 °C−1 across the genotypes. Measurements on six of the genotypes in root‐observation boxes showed the same differences between genotypes as found in the field, although the rate of rooting‐depth development was much higher. The observed differences in rooting depth and the fact that these differences could also be observed in a simple way in the root‐observation boxes, suggest that efficient breeding methods for rooting‐depth development can be developed.