Taxonomic evidences supporting the establishment of ‘sibujing', a traditional condiment crop from the Philippines, as Allium chinense G.Don

Abstract

‘Sibujing' is an emerging crop species in the Philippines with recorded traditional use as condiment in localized areas in Mindanao. However, its taxonomic identity is confused as it has been attributed to various taxa of Allium. We characterized the morphological, phytochemical and molecular characteristics of a ‘sibujing' accession to establish the taxonomic belonging and correct species name of the crop and elucidate its baseline characteristics for its continued utilization. Through next‐generation sequencing, we assembled the quadripartite genome of a ‘sibujing' accession from Zamboanga del Norte. The generated chloroplast genome revealed 100% similarity to the earlier established 152 525‐bp‐long A. chinense G.Don. plastome from China. Morphological characteristics also support this identification as both bears leaves with hollow 3–5‐angled cross‐sections, scapes that are terete and solid, and distinctly toothed filament base. Saponins were also detected from its methanolic extract. Phylogenetic reconstruction based on the sequenced ITS region, a nuclear barcode, suggested that the species was closest to taxa belonging to Allium sect. Sacculiferum subg. Cepa, further supporting its potential identity with A. chinense. Using a separate accession from a different locality in the Philippines, these findings were validated as the chloroplast genome assembled, phytochemical and morphological characteristics recorded were similarly established as close to A. chinense. This is the first definitive record of an Allium species from sect. Sacculiferum in the Philippines.