Identification Of The F₁ Hybrids Of Malus Xiaojinensis Using RAPD And SSR Molecular Markers

Mains xiaojinensis Cheng et Jiang is the first apple genotype identified as being resistant to Fe deficiency and resistant (or tolerant) to multiple environmental stresses. It is also tolerant to latent virus of apple trees and a precious wild germplasm in the genus Malus Miller. Malus baccata is one of the most important root stocks of the cultivated apple in China and a well-known Fe-inefficient genotype in the genus Malus. A full use of these two germplasms in apple root stock breeding has important theoretical and practical meanings for both apple industry in China and the sustainable utilization of the Malus germplasm in the world. Because of its apomictic reproduction character, an accurate and rapid identification of the F₁ hybrid seedlings of Malus xiaojinensis is of great importance to both genetic study and utilization of the precious genes in the germplasm. RAPD (Random Amplified Polymorphic DNA) marker is a simple, fast, and economic molecular technique for identifying the hybrid of fruit trees, but the relatively low reproducibility of some bands is still a practical problem with the RAPD molecular technique. To find a solution to this problem, 79 F₁ seedlings from M. xiaojinensis ×M. baccata were first analyzed using RAPD molecular markers, and then the assumed hybrid seedlings based on RAPD makers were tested by using SSR (Simple Sequence Repeat) markers in the present study. In addition, we also analyzed the morphological characters of the assumed hybrid seedlings identified based on molecular markers. Based on the...