Goro Hashimoto

Floral anthocyanins in wild taxa of Petunia (Solanaceae)

The flowers of 20 native taxa of Petunia (Solanaceae) were investigated by HPLC for the occurrence of anthocyanins. The investigation revealed the presence of at least 24 anthocyanins in their flowers, of which 18 known anthocyanins isolated from the flowers of P. exserta, P. guarapuavensis, P. integrifolia, P. occidentalis, and P. reitzii were fully identified by chemical and spectral methods to be 3-glucoside of delphinidin; 3-rutinosides of cyanidin, delphinidin, and petunidin; 3-rutinoside-5-glucosides, 3-trans and -cis-p-coumaroylrutinoside-5-glucosides, and 3-trans-caffeoylrutinoside-5-glucosides of delphinidin, petunidin, and malvidin; and 3-transcaffeoylglucosyl-trans-(caffeoyl or p-coumaroyl) rutinoside-5-glucosides of malvidin. Six novel anthocyanins were isolated from the flowers of P. occidentalis, and their structures were identified to be 3-glucosyl p-coumaroylrutinoside-5-glucosides and 3-glucosylcaffeoylrutinosides of petunidin and malvidin, and also 3-caffeoylglucosylcaffeoylrutinoside-5-glucoside and 3-caffeoylglucosyl p-coumaroylrutinoside-5-glucoside of petunidin. Out of the six pigments, petunidin 3-glucosyl p-coumaroylrutinoside-5-glucoside was unambiguously determined by spectral methods to be petunidin 3-O-[6-O-(4-O-(4-O-(β-d-glucopyranosyl)-trans-p-coumaroyl)-α-l-rhamnopyranosyl)-β-d-glucopyranoside]- 5-O-[β-d-glucopyranoside]. The 20 native taxa of Petunia could be placed into four groups (A, B, C, and D) with one further into five subgroups (D1–D5) regarding their constituents and contents of major anthocyanins and also their pigment biosynthesis with respect to the blocks or inhibitors of the hydroxylation, glucosylation, and acylation reactions in them. The use of anthocyanins as taxonomic markers in the genus Petunia is discussed in relation to the flower colour and possible pollination vectors.

Phylogenetic analysis of the genus Petunia (Solanaceae) based on the sequence of the Hf1 gene

Polymerase chain reaction fragment length polymorphisms and nucleotide sequences for a cytochrome P450 gene encoding flavonoid-3′,5′-hydroxylase, Hf1, were studied in 19 natural taxa of Petunia. Natural Petunia taxa were classified into six groups based on major insertion or deletion events that occurred only in intron II of the locus. The maximum parsimony method was used to calculate strict consensus trees based on nucleotide sequences in selected regions of the Hf1 locus. Petunia taxa were divided into two major clades in the phylogenetic trees. Petuniaaxillaris (including three subspecies), P. exserta, and P. occidentalis formed a clade with 100% bootstrap support. This clade is associated with a consistently inflexed pedicel, self-compatibility in most taxa, and geographical distribution in southern and western portions of the genus range. The other clade, which comprised the remainder of the genus is, however, less supported (up to 71% bootstrap); it is characterized by a deflexed pedicel in the fruiting state (except P. inflata), self-incompatibility, and a northeastern distribution. A nuclear gene, Hf1, seems to be a useful molecular marker for elucidating the phylogeny of the genus Petunia when compared with the nucleotide sequence of trnK intron of chloroplast DNA.

Differences in the floral anthocyanin content of red petunias and Petunia exserta.

In order to resolve a conflict between previous papers regarding the floral anthocyanins of red flowers of Petunia exserta, a naturally occurring species, the HPLC profile of this species was compared with that of commercial red garden petunias. Both HPLC profiles extremely superficially resemble each other in terms of relative amounts and retention times of the major anthocyanins. However, co-elution on HPLC of the mixed sample resulted in clear separation of the components. Three major anthocyanins in red petunias were determined to be cyanidin 3-sophoroside, cyanidin 3-glucoside and peonidin 3-glucoside, which exhibited similar behaviors on HPLC to delphinidin 3-glucoside. delphinidin-3-rutinoside and petunidin 3-rutinoside, respectively, the major floral anthocyanins of P. exserta.

Distribution of self-compatible and self-incompatible populations of Petunia axillaris (Solanaceae) outside Uruguay

Petunia axillaris occurs in temperate South America and consists of three allopatric subspecies: axillaris, parodii, and subandina. Previous studies have revealed that subsp. axillaris is self-incompatible (SI), subsp. parodii is self-compatible (SC) in Uruguay, and subsp. subandina is SC in Argentina. The SI/SC status over the entire distribution range is not completely understood, however. The objective of this study was to examine the overall SI/SC status of the respective subspecies in comparison with floral morphology. The results confirmed that subsp. parodii and subsp. subandina were SC throughout the distribution range, and that subsp. axillaris was also SC in Brazil and in most of the Argentinean territory. The SI P. axillaris occurs in the natural population only between 34 and 36°S, along the eastern shore of South America. The Brazilian and Uruguayan subsp. axillaris differed in SI/SC status and floral morphology. We discuss the cause of this difference.

Three groups of species in Petunia sensu Jussieu (Solanaceae) inferred from the intact seed morphology

The intact seed surface morphology in 45 taxa of Petunia sensu Jussieu native to South America (Petunia sensu Wijsman plus Calibrachoa) was compared under scanning electron microscopy. The existence of three groups of species, differentiated in terms of seed morphology, was revealed as follows: (1) all species of Petunia sensu Wijsman, having coarse wavy middle lamellae and anticlinal walls; (2) Calibrachoa parviflora and C. pygmaea, having fine wavy middle lamellae embedded in straight anticlinal walls; and (3) the other species of Calibrachoa, having straight middle lamellae and anticlinal walls. Close relationships between seed morphology and the other characteristics observable in the groups of species are discussed.

Two new species of Petunia (Solanaceae) from southern Rio Grande do Sul, Brazil

Petunia bajeensis and P. riograndensis, two new species from southern Rio Grande do Sul, Brazil are described, and their morphological distinction from related species and features of their habitats are discussed.

A new Brazilian species of Petunia (Solanaceae) from interior Santa Catarina and Rio Grande do Sul, Brazil

Petunia interior, a new species from interior Santa Catarina and Rio Grande do Sul, is described, and its morphological distinction from related species and features of its habitat are discussed.

A new Brazilian species of Petunia (Solanaceae) from the Serra da Mantiqueira

Petunia mantiqueirensis, a new species from the Serra da Mantiqueira, is described, and its morphological distinction from related species and features of the habitats are discussed.

Petunia guarapuavensis (Solanaceae): A new species from planalto of Paraná and Santa Catarina, Brazil

Petunia guarapuavensis, a new species fromplanalto (high plateau) of Paraná and Santa Catarina in Brazil, is described, and its morphological distinction from related species, features of the habitats, and geographical distribution are discussed.

Acylated delphinidin 3-rutinoside-5-glucosides in the flowers of Petunia reitzii.

Two acylated anthocyanins were isolated from selected individuals of Petunia reitzii, and identified to be delphinidin 3-O-[6-O-(4-O-(4-O-(6-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-tr ans-p-coumaroyl)-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside]- 5-O-[beta-D-glucopyranoside] and delphinidin 3-O-[6-O-(4-O-(4-O-(beta-D-glucopyranosyl)-trans-p-coumaroyl)-alph a-L-rhamnopyranosyl)-beta-D-glucopyranoside]-5-O-[beta-D-glucopyranoside ]. Nine known anthocyanins were also identified.