Transcriptome analysis to elucidate puffing disorder in Citrus

To identify genes associated with citrus peel development and manifestation of peel disorders, we analyzed flavedo, albedo and juice sac tissues from navel orange displaying, and not displaying, the puff disorder. Symptomatic and healthy “Navel” orange fruits were harvested from an orchard located in in Pauma Valley, San Diego County, California, USA. Sampling for all analysis (healthy or disordered Navel orange) was performed at the same time, from trees grown under the same agronomic, soil, and environmental conditions. Healthy and disordered fruits were analyzed at the mature stage. All transcriptome analysis was performed on mature fruit. For each type of fruit, three tissues (flavedo, albedo, and juice sacs) from three different trees (biological replicates) were separately analyzed. Four symptomatic fruits comprised one biological replicate each. Two healthy fruits comprised two biological replicates of control samples. A 1 cm-thick equatorial disc and four sections (N, S, E, and W) were cut per fruit. Each section of flavedo, albedo, and juice sac tissue was dissected. gene expression variation underlying quality trait, different genotypes