Notes: A widely spread common NC root. The semantic correlation "bitter":"sweet" is quite common (cf. the various meanings of *sal- and its derivates in Indo-European), thus the WC-EC comparison seems quite satisfactory. Note the frequent appearance of reduplication in this root (in PD, PL, PWC); we can probably reconstruct a reduplicated variant *q̇ĕq̇ĕɦlV already for PNC.
In PTs the stem obtained prefixed class markers (*-Vq̇VlV) with further standard adjectival development > *-Vq̇lV > *-Vlq̇V > PTs *-ɨ̃q̇V (nasalisation is a normal reflex of medial resonants).