Abstract - Wild ornamental germplasm exploration and domestication based on biotechnological approaches. In vitro colchicine treatment to obtain a new cultivar of Scoparia montevidiensis

Wild ornamental germplasm exploration and domestication based on biotechnological approaches. In vitro colchicine treatment to obtain a new cultivar of Scoparia montevidiensis

Alejandro S. Escandón*
Instituto de Floricultura
Instituto Nacional de Tecnologia Agropecuaria (INTA)
INTA Castelar, De los Reseros y Las Cabañas s/n. 1712
Pcia. Buenos Aires, Argentina
Tel/Fax: 54 11 46 21 94 75
E-mail: aescandon@castelar.inta.gov.ar

Ikuo Miyajima^#Centro Tecnológico de Flori, Fruti y Horticultura of
Japan International Cooperation Agency in Argentine (JICA-CETEFFHO)
INTA Castelar, De los Reseros y Las Cabañas s/n. 1712
Pcia. Buenos Aires, Argentina
Tel/Fax: 54 11 46 21 94 75
E-mail:cxx00130@nifty.com

Marisol Alderete
Instituto de Floricultura
Instituto Nacional de Tecnologia Agropecuaria (INTA)
INTA Castelar, De los Reseros y Las Cabañas s/n. 1712
Pcia. Buenos Aires, Argentina
Tel/Fax: 54 11 46 21 94 75
E-mail: limarial@hotmail.com

Juan Carlos Hagiwara
Instituto de Floricultura
Instituto Nacional de Tecnologia Agropecuaria (INTA)
INTA Castelar, De los Reseros y Las Cabañas s/n. 1712
Pcia. Buenos Aires, Argentina
Tel/Fax: 54 11 46 21 94 75
E-mail: jhagiwara@cnia.inta.gov.ar

Gabriela Facciuto
Instituto de Floricultura
Instituto Nacional de Tecnologia Agropecuaria (INTA)
INTA Castelar, De los Reseros y Las Cabañas s/n. 1712
Pcia. Buenos Aires, Argentina
Tel/Fax: 54 11 46 21 94 75
E-mail: gfacciuto@cnia.inta.gov.ar

Diego Mata
Instituto de Floricultura
Instituto Nacional de Tecnologia Agropecuaria (INTA)
INTA Castelar, De los Reseros y Las Cabañas s/n. 1712
Pcia. Buenos Aires, Argentina
Tel/Fax: 54 11 46 21 94 75
E-mail: dmata@cnia.inta.gov.ar

Silvina M. Soto
Instituto de Floricultura
Instituto Nacional de Tecnologia Agropecuaria (INTA)
INTA Castelar, De los Reseros y Las Cabañas s/n. 1712
Pcia. Buenos Aires, Argentina
Tel/Fax: 54 11 46 21 94 75
E-mail: ssoto@cnia.inta.gov.ar

Website: http://cirn2.inta.gov.ar/jica/

*Corresponding author

Financial support: The present work was supported by the INTA JICA agreement, project: Argentina Floriculture Development.

Keywords: chimera, flow cytometry, micropropagation, ornamental plants, tetraploid.

^#Present address: Institute of Tropical Agriculture, Kyushu University, Fukuoka 812-8581, Japan.

Abbreviations:

BAP- 6: benzyl amino purine;
DMSO: dimethylsulfoxide;
MS: Murashige and Skoog (1962);
NAA: naphthalene acetic acid.

The genus Scoparia is native from Argentina. The diversity of colours and shape of their flowers bestows this genus a very interesting ornamental potential. The purpose of the present study is to explore the Scoparia species germplasm by means of in vitro polyploidization in order to improve their ornamental qualities. Accessions of S. montevidiensis var. montevidiensis, S. montevidiensis var. glandulifera, S. nudicaulis, S. hasleriana and S. dulcis were collected and maintained under greenhouse conditions. The Murashige-Skoog medium, supplemented with 0.25 mg/L BAP was used for the nodal segments multiplication of the five Scoparia species. Except for S. hasleriana, the multiplication rate of the other species ranged between 10 and 12 shoots per explant. The colchicine doses tested with S. montevidiensis were: 0.0; 0.1; 0.05; 0.01 and 0.001% (24 and 48 hrs). From a total of 364 recovered plants, 4 solid tetraploid and 16 chimeras were detected. Significant differences were observed for the size of flower, leaves, and the stem diameter among the tetraploid plants and between them and the control. The tissue culture proved to be a powerful tool both to multiply the Scoparia material incorporated to our germplasm collection and to obtain new improved varieties of this beautiful genus.