Abstract:

The density of oil gland is an important factor to determine the content of essential oil in citrus. To understand the genetic control of oil gland development，a segregation population of 159 F1 individuals was constructed by crossing Luowen kumquat[Fortunella japonica（Thunb.）Swingle]with Huapi kumquat（F. crassifolia Swingle‘Huapi’），a low oil gland density mutation variety. Thirty individuals of each extreme phenotype group with either high-density or low-density oil glands were chosen and their DNA were pooled to construct two DNA pools for genomic re-sequencing to identify candidate genes associated with oil gland development. The results of Bulked Segregant Analysis（BSA）indicated that the 25 980 001–29 160 001 bp region of chromosome 9 is highly correlated to the density of oil glands. Through analysis of recombination frequency of SNP，511 SNP loci distributed in 301 genes were found to be possibly associated with the density of oil glands. The homology function analysis suggested that 11 of these genes（Ciclev10005243m.g，Ciclev10005288m.g，Ciclev10005338m.g，Ciclev10005441m.g，Ciclev10006448m.g，Ciclev10005804m.g，Ciclev10004719m.g，Ciclev10005888m.g，Ciclev10006502m.g，Ciclev10005197m.g and Ciclev10004431m.g）involving in cell programmed death，the function and construction of cell wall，and cell elongation and expansion may be the important genetic factors controlling the development of oil gland.

Key words: kumquat, oil gland development, re-sequencing and BSA, homologous analysis, functional annotation