Phylogenetic tree of PtHMGR and other HMGRs. The GenBank accession numbers of the HMGRs are as follows: Populus trichocarpa, XM_002316990.2; Arabidopsis thaliana, NM_106299.4; Camellia sinensis, KF649853.1; Camptotheca acuminata, AAB69727.1; Capsicum annuum, XM_016704840.1; Capsicum baccatum, MLFT02000002.1; Capsicum chinense, CIT02000002.1; Cephalotus follicularis, BDDD01003560.1; Cestrum nocturnum, KY703396.1; Coffea arabica, HQ540670.1; Cucumis melo, NM_001297451.1; Cucurbita moschata, XM_023090472.1; Dimocarpus longan, JN034591.1; Eucalyptus grandis, XM_010062927.2; Euphorbia lathyris, JQ694150.1; Euphorbia pekinensis, EF062569.1; Hevea brasiliensis, XM_021830837.1; Ipomoea nil, XM_019327336.1; Jatropha curcas, XM_012232190.2; Juglans regia, XM_018987497.1; Lactuca sativa, XM_023892538.1; Litchi chinensis, JN034589.1; 728.1; Nicotiana benthamiana, LC382275.1; Nicotiana sylvestris, XM_009782484.1; Nicotiana tabacum, NM_001326284.1; Nicotiana tomentosiformis, XM_009602774.2; Oryza sativa, AF110382.1; Panax quinquefolius, FJ755158.2; Papaver somniferum, XM_026548454.1; Ricinus communis, XM_002510686.3; Solanum chacoense, JF802615.1; Solanum pennellii, XM_015210528.1; Solanum tuberosum, NM_001288155.1; Withania somnifera, KX574809.1; Zea mays, NM_001153261.1; and Ziziphus jujuba, XM_016024520.2. The tree was constructed using the neighbor-joining method in MEGA 5.1 and bootstrapped 1000 times. Bootstrap percentages are indicated at the branch points. In all cases, tree topologies obtained using the NJ, minimum evolution, and maximum parsimony methods were identical. The numbers on the nodes represent the bootstrap values.