Estabolishment Of Sweetpotato ISSR Molecular Markers And Molecular Cloning And Functional Identification Of The Isopentenyl Diphosphate Isomerase Gene From Ipomoea Batatas (L.) Lam.

Sweetpotato , Ipomoea batatas (L.) Lam., ranks the forth staplest foodstuff crop in China, of which productivity and planting area are the first in the world. Because of its many biological complexities such as natural hereozygote and cross-incompatibility, the analysis of the genetic relationships among cultivars is of interest not only for germplasm conservation but for breeding purposes. Molecular techniques have been used widely for germplasm characterization, variety identification, phylogenetic study and diversity analysis. There have been very simple reports analyzing genetic relationships among sweetpotato cultivars with known origin using molecular markers. In the present study, genetic relationships among thirteen sweetpotato cultivars with known origin were analyzed using Inter-simple sequence repeat (ISSR) molecular markers.Sweetpotato provide both carbohydrate and important nutrients for human; among them, carotenoids, especially p-carotene are the most important nutrients in sweetpotato that is the precursor of vitamin A. In fact, sweetpotato is the main source that provides p-carotene for the people in the developing countries in Africa and Southeast Asia. The limiting contents of β-carotene in sweetpotato causes vitamin A deficiency related diseases such as xerophthalmia, corneal lesions, keratomalace and, in many instances, death. Carotenoids including p-carotene belong to the family of isoprenoids, which is synthesized from the general essential 5-carbon precursor isopentenyl diphosphate (IPP)and its isomer, dimethylallyl diphosphate (DMAPP). Isopentenyl diphosphate isomerase (IPI) is the enzyme that catalyzes the reversible conversion of IPP and DMAPP. In the present study, a new isopentenyl diphosphate isomerase gene from carotenoid-rich sweetpotato cultivars (namely YUSU303 developed ourselves) involved in the carotenoid precursor pathway was cloned, characterized and functionally expressed.1 Sweetpotato ISSR Molecular MarkersIn the present study, a method was established that could be employed to isolate high-quality...