ESTABLISHMENT OF in vitro GERMINATION AND GROWTH CONDITIONS OF Distichlis spicata.

Abstract

Highly tolerant plant species, such as the native grass Distichlis spicata var. stricta (L) Greene shows great potential for use as a model system to study salinity and water stress tolerance in plants; and as forage during drought or flooding periods, or in saline/alkaline and infertile soils. However, D. spicata is known to have an extremely low germination rate (3%) in field. To strictly and consistently study this system, it is essential to establish in vitro germination and growth conditions, as in field multiple factors affect results during experimentation. In order to establish in vitro germination and growth under controlled laboratory conditions as well as to enhance germination rates, we tested the effects on contamination and germination rates of several antiseptic agents and mechanical scarification and stratification seed treatments. Results from seed treatments that included mechanical scarification, stratification and treatment with sodium dicloroisocyanurate (NaDCC) 20% (w/v) proved to be the best procedure to significantly enhance disinfection and germination up to 80% in only 6 days. After germination tests, ten days after seeded, plantlets were successfully established in pots in growth chamber and green house conditions. Thus, we have successfully established D. spicata in vitro germination and growth conditions which allow the study of this grass under controlled conditions, and increase its potential for propagation in poor soil conditions.