Production of Intergeneric Hybrids Between <i>Argyranthemum frutescens</i> (L.) Sch. Bip. and <i>Rhodanthemum gayanum</i> (Cross. & Durieu) B.H. Wilcox, K. Bremer & Humphries Using Embryo Culture and Gene Markers for Discrimination

Abstract

In this study, we performed intergeneric crosses betweenArgyranthemum frutescens (L.) Sch. Bip. and seven perennial species of closely related genera [Artemisia absinthium L., Chrysanthemum lavandulifolium (Fisch. ex Trautv.) Makino × Chrysanthemum × morifolium Ramat., Dimorphotheca sinuata DC., Osteospermum ecklonis (de Candolle) Norlindh, Pericallis hybrida B. Nord., Rhodanthemum gayanum (Cross. & Durieu) B.H. Wilcox, K. Bremer & Humphries., and Rhodanthemum hosmariense (Ball) B.H. Wilcox, K. Bremer & Humphries.].Using an embryo culture technique to generate intergeneric hybrids, we produced two putative hybrids from the crosses between A. frutescens and R. gayanum. In the putative hybrid derived from the cross between A. frutescens 'Brilliant rouge' × R. gayanum 'Elf pink', its ligulate flower color was similar to the 'Brilliant rouge' seed parent while the composition and total amount of anthocyanidins and/or leucoanthocyanidins were different. In the putative hybrid derived from the cross between A. frutescens 'Sunday ripple' and R. gayanum 'African eyes', its ligulate flower color differed from those of the parents. The ligulate flowers of the parents were white and produced no anthocyanidins, whereas the putative hybrids had light pink ligulate flowers and produced three anthocyanidins pigments [pelargonidins (including pelargonidin and/or leucopelargonidin), cyanidins (including cyanidin and/or leucocyanidin, peonidin), and delphinidins (including delphinidin and/or leucodelphinidin, malvidin)]. In addition, the cleaved amplified polymorphic sequence (CAPS) markers (Afl II) developed in this study confirmed that the putative hybrids were intergeneric hybrids of A. frutescens × R. gayanum. Therefore, these CAPS selection markers can be used to determine whether plants resulting from crosses are hybrids.Islands (Spain) and Madeira Islands (Portugal) (Bramwell and Bramwell, 2001;Press and Short, 1994). Plants of the genus Argyranthemum, of which there are 24 wild species, were introduced to Japan sometime between 1860 and 1880 (Bremer, 1994;Kitamura, 1988). To date, more than 200 cultivars of A. frutescens have been registered, many of which are bred for the cut and potted flower trade in Japan.The two primary methods for breeding plants are cross-breeding (intraspecific, interspecific, and intergeneric hybridization) and mutation breeding including

Development of the sequence-characterized amplified region (SCAR) marker for distinction of intergeneric hybrids between <i>Argyranthemum frutescens</i> (L.) Sch. Bip. and <i>Rhodanthemum gayanum</i> (Coss. & Durieu) B.H. Wilcox, K. Bremer & Humphries

“…Furthermore, to obtain new intergeneric hybrids with better cultivation characteristics than the current hybrids, we created a hybrid of A. frutescens×Rhodanthemum gayanum using an embryo culture technique, and the cleaved amplified polymorphic sequences (CAPS) marker was able to distinguish between hybrids of A. frutescens×R. gayanum (Muto et al 2020). To increase the efficiency of breeding, it is necessary to consider improving the embryo culture conditions and simplifying distinction method of hybrids.…”

Obtainment and confirmation of intergeneric hybrids between marguerite (<i>Argyranthemum frutescens</i> (L.) Sch.Bip.) and two <i>Rhodanthemum</i> species (<i>R. hosmariense</i> (Ball) B. H. Wilcox, K. Bremer & Humphries and <i>R. catananche</i> (Ball) B. H. Wilcox, K. Bremer & Humphries)

“…Nine A. frutescens strains as seed parents ("08-23-1-X-1", "08-23-1", "P18-93-01", "11-16-2", "P12-26-1", "P14-32-1", "P16-62-03", 'Moonlight' , and "P19-34-02") and three Rhodanthemum species (R. hosmariense, R. catananche, and R. gayanum [Control plants; intergeneric hybridization with A. frutescens via embryo culture has been reported (Muto et al 2020a)]) as pollen parents were used in this study. All cross combinations are shown in Table 1.…”

“…A DNeasy Plant Mini Kit (Qiagen, Hilden, Germany) was used to extract genomic DNA from 50 mg of young leaves collected from each plant. Hybridization was determined using genetic markers and performed according to a previously reported method (Muto et al 2020a). The ITS region of nuclear ribosomal DNA was amplified using the primer pair 5′-AGA AAT CGT AAC AAG GTT TCC GTA GG-3′ (Zhao et al 2010) and ITS4 5′-TCC TCC GCT TAT TGA TAT GC-3′ (White et al 1990).…”

“…PCR products were subsequently digested with the restriction enzyme Afl II, which was used for hybrid determination (Muto et al 2020a). The restriction enzyme reaction mixture (10 µl) contained 5 µl PCR amplification products, 0.5 µl restriction enzyme Afl II (10 U•µl −1 ), 1 µl 10×M buffer, 1 µl 0.1% BSA, and sterilized water to make 10 µl.…”

“…Bip., and Rhodanthemum gayanum (Coss. & Durieu) B. H. Wilcox, K. Bremer & Humphries as pollen parents (Katsuoka et al 2022;Muto et al 2020a;Ohtsuka and Inaba 2008). Among these crosses, the hybrid cultivars "Bijoumum rosequartz (tentative name, former strain name "Izu No.…”