การศึกษาความหลากหลายทางพันธุกรรมของส้มจุกโดยครื่องหมายอาร์เอพีดี

Abstract

Neck orange has the original planting area in Chana District, Songkhla Province. However, the planting area has dramatically decreased. The aims of this study are to collect and assess genetic diversity of neck orange by using fruit morphology and DNA markers. In this study, ninety-five samples were collected from Songkhla, Trang and Surat Thani provinces. Seventy-four samples were using for fruit morphological characterization. According to fruit physical characteristics, fruit weight was in the range of 201-250 g. An average fruit diameter was 7.52 cm. The high of fruit polar was on average 1.0 cm with ranged from 1.01- 1.50 cm Fruit chemical characteristics including juice content was on an average 35.5 percent. Total soluble solids (TSS), titratable acidity and the ratio between total soluble solids and titratable acidity (TSS/TA) were ranged from 8-10 oBrix, 0.31-0.50 percent and 15.1-20.0, respectively. Genetic diversity of ninetyfive samples was analyzed by five RAPD primers including OPA-10, OPA-12, OPA-18, OPB-01, and OPZ-11. Result from a dendrogram analysis based on RAPD markers, 2 clusters could be separated with similarity coefficients ranging from 0.48-0.98 with an average of 0.73. Genetic variability of neck orange progenies from 6 mother plants was investigated by two RAPD primers (OPA-18 and OPZ-11. There were 1 to 4 seedlings per seed with an average percentage of polyembryony was 42.5 percent. Therefore, seed propagation of neck orange may result in genetic variation. Farmers can propagate by seeds but they have to prove that seedlings are nucellus.