Fig 1.
Images of lentil seeds with normal brown (Ggc Tgc Tan), zero-tannin gray (Ggc tan), and zero-tannin transparent (ggc tan) lentil seed coats.
Table 1.
Phenolic compound characteristics in selected reaction monitoring (SRM), including sub-class, retention time, molecular ion, and optimum fragment ion in positive or negative mode.
Table 2.
Proanthocyanidin characteristics in single ion monitoring (SIM), including retention time and molecular ion in positive mode.
Fig 2.
Mean area ratio per mg sample obtained for different sub-classes of phenolic compounds in (A) selected reaction monitoring (SRM) mode and (B) single ion monitoring (SIM) mode in cotyledon, embryo, and seed coat fractions of lentils with genotype Ggc Tgc Tan; C and G indicate catechin/ epicatechin and gallocatechin/ epigallocatechin, respectively.
Fig 3.
Mean area ratio per mg sample obtained for different sub-classes of phenolic compounds in (A) SRM mode and (B) SIM mode for transparent, gray translucent, and brown opaque lentil seed coats; C and G stand for catechin/ epicatechin and gallocatechin/ epigallocatechin, respectively.
Fig 4.
Structure of LcubHLH highlighting the region of the variant related to tan.
The tan lines (Cedar, Shasta and CDC Gold) all have a deletion relative to the Tan lines (964a-46, CDC Redberry, and CDC Robin). The gene structure and the sequence alignment were obtained by FancyGene [28] tool and BioEdit [29] alignment software, respectively.
Fig 5.
Putative biochemical pathway of phenolic compounds in lentil seed coats, as well as whether or not the final product of different branches of phenylpropanoid are observed in Tan and/ or tan genotypes.
Abbreviations: PAL, phenylalanine ammonia lyase; C4H, cinnamic acid 4-hydroxylase; 4CL, 4-coumaric acid:CoA ligase; STS, stilbene synthase; CHS, chalcone synthase; F3H, flavanone-3-hydroxylase; F3’H, flavonoid-3’-hydroxylase; F3’5’H, flavonoid-3’,5’-hydroxylase; FLS, flavonol synthase; DFR, dihydroflavonol reductase; ANS, anthocyanidin synthase; LAR, leucoanthocyanidin reductase; ANR, anthocyanidin reductase; gluc, glucoside; rut, rutinoside; robin, robinoside; rhamn, rhamnoside. Filled circles represent the transparent, gray, and brown seed coat colours. Information with respect to the pathway originates from [9–12].
Table 3.
Mobile phase gradient used in this experiment, where solvent A and B were water: formaic acid (99;1, v/v) and water: acetonitrile: formic acid (9:90:1, v/v/v), respectively.