Samples were flash-frozen in liquid nitrogen, and ground into fine powder using a beadbeater. Total RNA was extracted using an RNeasy Plant Mini Kit (Qiagen) followed by purification using the RNA Clean & Concentrator Kit (Zymo Research). Purified RNAs were quantified using a Nanodrop (ThermoFisher) and quality control was performed by an Agilent Bioanalyzer 2100. PacBio Sequel II library preparation and RNA-sequencing (Iso-Seq) was performed by UC Davis DNA Technologies & Expression Analysis Core (https://dnatech.genomecenter.ucdavis.edu/pacbio-library-prep-sequencing/). PacBio Sequel II