diarch

1. The primary meristem consisted of calyptrogen, primordial epidermis, periblem and plerome, while the primary structure consisted of epidermid, cortex and central cylinder.Primary xylem is diarch.

原分生组织来源于胚根，由3群原始细胞组成，具有典型分生组织的细胞学特征；

2. The results showed that the primary xylem of the root is diarch, triarch and tetrarchy;