Proceedings
of the XLV Italian Society of Agricultural Genetics - SIGA Annual Congress
Salsomaggiore Terme, Italy - 26/29 September, 2001
ISBN 88-900622-1-5
Poster Abstract
PLANT REGENERATION FROM CALLUS OF THE APOMICTIC GRASS PASPALUM
SIMPLEX
MOLINARI L., BUSTI A.,
PUPILLI F., ARCIONI S.
Istituto di Ricerche sul
Miglioramento Genetico delle Piante Foraggere del CNR, Via della Madonna alta
130, 06128 Perugia, Italy
Paspalum simplex is a wild
subtropical grass characterised by both sexual and apomictic reproduction.
Tetraploid apomictic accessions are sexually compatible with diploid sexual
races making this species an interesting model system to study apomixis through
map-based strategies. The aim of
this research was to develop a protocol for plant regeneration from both
sexual and apomictic lines of this species in the perspective of testing the
effect of apomixis-related sequences isolated from the apomictic genotypes
through transformation. Different explants and concentrations of growth regulators
were tested and a rapid and efficient regeneration was obtained. The best
explants were hypocotyls dissected from ten-day-old seedlings grown in aseptic
conditions and controlled environment. The best culture medium for callus
induction was based on MS salts (Murashige and Skoog, 1962) enriched with
thiamine-HCl 0.4 mg l-1, myoinositol 100 mg l-1, sucrose
30 mg l-1, solidified with 8 g l-1 of agar and containing
2 mg l-1 of 2,4-D and 0.05 mg l-1 kinetine as growth
regulators. Early regenerating structures were observed on callus surface after
6-weeks of culture on callus induction medium. Such structures evolved into
well developed shoots after two weeks of culture on the same culture medium as
before, replacing the growth regulators with NAA 0.5 mg l-1, and
6-BAP 2 mg l-1. The shoots formed well developed root systems after
two weeks of incubation on the same medium without growth regulators.
No significant differences for regeneration capability were noted between
sexual and apomictic genotypes.