75 plant species have been studied. The plant species were selected on the basis of the following criteria: (1) the natural product composition of the species; (2) the commercial importance of the plant and/or the natural products; and (3) the availability of sufficient tissue for RNA and metabolite isolation.

Species Common name Family PI
Papaver bracteatumLindl. Persian poppy Papaveraceae Facchini, P.
Sanguinaria canadensisL. Bloodroot Papaveraceae Facchini, P.
Chelidonium majusL. Greater celandine Papaveraceae Facchini, P.
Stylophorum diphyllum(Michx.) Nutt. Celandine poppy Papaveraceae Facchini, P.
Eschscholzia californicaCham. California poppy Papaveraceae Facchini, P.
Glaucium flavumCrantz Yellow hornpoppy Papaveraceae Facchini, P.
Argemone mexicanaL. Mexican prickly poppy Papaveraceae Facchini, P.
Thalictrum flavumL. Meadow-rue Ranunculaceae Facchini, P.
Hydrastis canadensisL. Goldenseal Ranunculaceae Facchini, P.
Nigella sativaL. Black cumin Ranunculaceae Facchini, P.
Xanthorhiza simplicissimaMarshall Yellowroot Ranunculaceae Facchini, P.
Berberis thunbergiiDC. Japanese barberry Berberidaceae Facchini, P.
Mahonia aquifolium(Pursh) Nutt. Oregon-grape Berberidaceae Facchini, P.
Jeffersonia diphyllaL. (Pers.) Twinleaf Berberidaceae Facchini, P.
Menispermum canadenseL. Canadian moonseed Menispermaceae Facchini, P.
Corydalis cheilanthifoliaHemsl. Fern-leaf corydalis Papaveraceae Facchini, P.
Nandina domesticaThunb. Sacred bamboo Berberidaceae Facchini, P.
Cissampelos mucronataA. Rich. Abuta Menispermaceae Facchini, P.
Tinospora cordifolia(Thunb.) Miers Heartleaf moonseed Menispermaceae Facchini, P.
Cocculus trilobus(Thunb.) DC. Korean moonseed Menispermaceae Facchini, P.
Petasites hybridus(L.) G.Gaertn., B. Mey. & Scherb. Butterbur Asteraceae Ro, D.
Matricaria recutitaL. German chamomille Asteraceae Ro, D.
Valeriana officinalisL. Valerian Valerianaceae Ro, D.
Citrus paradisiMacfad. Grapefruit Rutaceae Ro, D.
Lippia dulcis(Trevir.) Moldenke Aztec sweet herb Verbenaceae Ro, D.
Arnica chamissonisLess. Chamisso arnica Asteraceae Ro, D.
Arnica montanaL. Leopard bane Asteraceae Ro, D.
Lactuca sativaL. Lettuce Asteraceae Ro, D.
Xanthium strumariumL. Rough cocklebur Asteraceae Ro, D.
Ligularia fischeri(Ledeb.) Turcz. Gomchwi Asteraceae Ro, D.
Thapsia garganicaL. Drias plant Apiaceae Ro, D.
Chrysanthemum coronariumL. Garland chrysanthemum Asteraceae Ro, D.
Artemisia chamaemelifoliaVill. Chamomile-leaved artemisi Asteraceae Ro, D.
Artemisia absinthiumL. Absinthe wormwood Asteraceae Ro, D.
Artemisia maritimaL. Sea wormwood Asteraceae Ro, D.
Humulus lupulusL. Common hop Cannabaceae Page, J.
Primula obconicaHance Poison/German primrose Primulaceae Page, J.
Hypericum perforatumL. St. John's wort Hypericaceae Page, J.
Cannabis sativaL. Cannabis Cannabaceae Page, J.
Piper methysticumG. Forst. Kava Piperaceae Page, J.
Helichrysum petiolareHilliard & B.L. Burtt Licorice-plant Asteraceae Page, J.
Vancouveria hexandra(Hook) C. Morren & Decne. White inside-out flower Berberidaceae Page, J.
Rheum rhabarbarumL. Garden rhubarb Polygonaceae Page, J.
Hydrangea macrophylla(Thunb.) Ser. Bigleaf hydrangea Hydrangeaceae Page, J.
Pelargonium x hortorumL.H. Bailey Common geranium Geraniaceae Page, J.
Prunella vulgarisL. Common selfheal Lamiaceae Covello, P.
Platanus occidentalisL. American sycamore Platanaceae Covello, P.
Centella asiatica(L.) Urban Indian pennywort, gotu kola Apiaceae Covello, P.
Saponaria vaccariaL. Prairie carnation, cowcockle Caryophyllaceae Covello, P.
Dianthus superbusL. Large pink Caryophyllaceae Covello, P.
Silene vulgaris(Moench) Garcke Bladder campion Caryophyllaceae Covello, P.
Acacia victoriaeBenth Gundabluie Fabaceae Covello, P.
Diospyros kakiL. f. Japanese persimmon Ebenaceae Covello, P.
Swietenia mahagoni(L.) Jacq. West Indian mahogany Meliaceae Covello, P.
Cedrela sinensis (Toona sinensis) (A. Juss.) M. Roem. Chinese mahogany Meliaceae Covello, P.
Vinca minorL. Lesser periwinkle, myrtle Apocyanaceae DeLuca, V.
Rauwolfia serpentina(L.) Benth. ex Kurz Indian snakeroot Apocyanaceae DeLuca, V.
Camptotheca acuminataDecne. Happy tree, tree of life Nyssaceae DeLuca, V.
Lonicera japonicaThunb. Japanese honeysuckle Caprifoliaceae DeLuca, V.
Cinchona ledgeriana(Howard) Bern. Jesuit's bark Rubiaceae DeLuca, V.
Catharanthus ovalisMarkgr. Catharanthus ovalis Apocyanaceae DeLuca, V.
Catharanthus longifolius(Pichon) Pichon Catharanthus longifolius Apocyanaceae DeLuca, V.
Tabernaemontana elegansStapf Milkwood, toad tree Apocyanaceae DeLuca, V.
Amsonia hubrichtiiWoodson Hubricht's bluestar Apocyanaceae DeLuca, V.
Catharanthus roseus(L.) G. Don Rosy periwinkle Apocyanaceae DeLuca, V.
Abies balsameaL. (Mill.) Balsam fir Pinaceae Bohlmann, J.
Grindelia integrifoliaDC. Entire-leaved gumwood Asteraceae Bohlmann, J.
Pseudolarix amabilis(J. Nelson) Rehder Golden larch Pinaceae Bohlmann, J.
Tripterygium wilfordiiHook. f. Thunder god vine Celastraceae Bohlmann, J.
Euphorbia peplusL. Cancer weed Euphorbiaceae Bohlmann, J.
Marrubium vulgareL. Common horehound Lamiaceae Bohlmann, J.
Jatropha gossypiifoliaL. Cotton leaf Euphorbiaceae Bohlmann, J.
Coleus forskohlii(Poir.) Briq. Coleus Lamiaceae Bohlmann, J.
Rosmarinus officinalisL. Rosemary Lamiaceae Bohlmann, J.
Isodon rubescensHemsl. Isodon Lamiaceae Bohlmann, J.