Comparative study on shallot (Allium cepa L. Aggregatum Group) from Vietnam and the surrounding countries

Abstract

The relationship between the shallot strains in Vietnam and those in the surrounding countries was studied by comparing their morphological and physiological characteristics and DNA polymorphisms. The morphological and physiological observations demonstrated that the strain from Taiwan was similar to those of the North type cultivated in northern Vietnam while those from Thailand, the Philippines, Malaysia, and Indonesia were akin to the South type cultivated in central and southern Vietnam. The strain from China (Kunmin) was similar to the North type rather than the South type although it had characteristics of both types. In the RAPD analysis, the strains from Taiwan, China, and the North type were formed into one group, whereas those from Thailand, the Philippines, Malaysia, Indonesia, and the South type formed the other group. With the unique characteristics, restricted distribution and long history of cultivation, it is supposed that the North type shallot had differentiated in the North region of Vietnam, while the South type seems to be a variant of the shallot strain distributed universally in the tropical zone of Southeast Asia.