Project title : Regulation of Farnesene Synthesis to Control Scald PI : Bruce D . Whitaker Organization : USDA - ARS , Produce Quality and

Objectives: (1) Obtain a genomic clone of the apple α-FS gene including the promoter and ethylene response element(s); (2) Isolate and characterize the promoter region from the genomic clone of the apple peel HMG2 gene and determine whether expression of HMG2 is regulated by ethylene; (3) Evaluate the correlation of ethylene-induced transcription of genes encoding enzymes in the αfarnesene synthetic pathway with accumulation of α-farnesene during storage, and with the incidence and severity of scald development; (4) Transform apple shoots with antisense or RNAi constructs of the α-FS gene (and the HMG2 gene if time allows) driven by either the CaMV 35S or apple α-FS promoter and test transgenic apple plants for suppression of α-farnesene production.