Implemented by: Michael Melkonian and Barbara SurekThe protocol for RNA isolation using TRI Reagent (Molecular Research Center, Cincinnati OH) is analogous to the TRIzol LS Reagent protocol except that 1 ml of TRI Reagent is added to each 250 μl of homogenized material (= approx. 50–100 mg packed cell volume) (step 3, Protocol 10). For background, TRI Reagent combines phenol and guanidine thiocyanate in a monophasic solution to inhibit RNase activity during RNA isolation.This protocol is part of a collection of eighteen protocols used to isolate total RNA from plant tissue. (RNA Isolation from Plant Tissue Collection: https://www.protocols.io/view/rna-isolation-from-plant-tissue-439gyr6)