W530 Chilling Requirement and Bloom Date in Peach: Genetic and Genomic Approaches for Deciphering a Complex Gene Network

Date: Tuesday, January 17, 2012
Time: 4:30 PM
Room: Royal Palm Salon 4,5,6
Tatyana Zhebentyayeva , Clemson University, Clemson, SC
Shenghua Fan , Clemson University, Clemson, SC
Bode Olukolu , North Carolina State University
Abdelali Barakat , Clemson University, Clemson, SC
Sherri Hughes-Murphree , Clemson University, Clemson, SC
Carmen Leida , Instituto Valenciano de Investigaciones Agrarias (IVIA), Valencia, Spain
Marisa Badenes , Instituto Valenciano de Investigaciones Agrarias (IVIA), Valencia, Spain
Douglas G. Bielenberg , School of Agricultural, Forest & Environmental Sciences, Clemson University, Clemson, SC
Gregory L. Reighard , School of Agricultural, Forest & Environmental Sciences, Clemson University, Clemson, SC
Chittaranjan Kole , Institute of Nutraceutical Research, Clemson, SC
William R. Okie , ARS-USDA S.E. Fruit & Tree Nut Research Lab , Byron, GA
Albert G. Abbott , Department of Genetics and Biochemistry, Clemson University, Clemson, SC
In spite of significant progress in understanding flowering biology in Arabidopsis and rice, in perennial plants the mechanisms establishing and controlling bud dormancy and its release are poorly understood.  We used a combined genetic and genomic approach to gain insights into control of dormancy related traits in fruit trees. Using QTL mapping data in two Prunus species (peach and apricot) and the peach genome (Prunus persica v1.0, www.rosaceae.org), we identified the sequences of genomic regions underlying the significant QTL intervals. Based on flowering and vernalization pathways in Arabidopsis, we mined the peach genome for candidate genes that are co-localized with QTLs and potentially involved with chilling requirement and bloom date.  Due to lack of recent genome wide duplications, potential molecular network for control of dormancy release in peach is simplified compared with that in other perennial woody species and Arabidopsis. This fact might explain the significant “strength” of a limited number of peach QTLs for dormancy related traits compared with that in other trees. To get further insight into QTL intervals, we are employing an Illumina platform for deep re-sequencing of 2 high- vs. 2 low-chill individuals with fixed haplotypes within major QTL intervals on G1 and G7. We generated ~15 mln 100bp-paired-ends-reads representing ~13x coverage per haplotype and mapped them against the peach genome using the CLCbio software (http://www.clcbio.com). In this communication, we present these data in combination with other data that have been used to develop a potential network of candidate genes for control of these phenological traits.