Response to NaCl of alfalfa plants regenerated from non-saline callus cultures

Abstract

Salinity restricts crop productivity in many arid environments. Inadvertent selection for tolerance to osmotic stress may occur under cell or tissue culture conditions and could affect the performance of regenerated plants. The effect of NaCI on forage produced by alfalfa (Medicago sativa L.) plants regenerated from non-saline callus cultures was examined in this study. Plants of Regen-S, which was selected for improved callus growth and regeneration in non-saline cultures, had higher forage weight when grown on SHII medium at NaC1 levels up to 100 mM compared to its parental cultivars, Saranac and DuPuits. Five additional original-regenerant plant pairs, each derived from non-saline callus cultures of different alfalfa plants, were evaluated in a solid (soil-like) substrate under saline and non-saline conditions. Weight of forage produced by rooted stem cuttings of regenerated plants was 33% higher at 50 mM NaCI compared to cuttings of explant donor plants. Self progenies from four of five regenerants had higher relative forage weight at 100 mM NaCI (percent of 0 NaCI treatment) than the original plants indicating increased NaC1 tolerance.

The effect of salt stress and abscisic acid on proline production, chlorophyll content and growth of in vitro propagated shoots of Eucalyptus camaldulensis

“…callus, suspension culture and shoot culture) to screen for cells and tissues that show variation in their ability to tolerate relatively high levels of salt (NaCl) in media. Investigators have concentrated on agricultural species with some success (at least initially) in plants such as legumes (Smith and McComb, 1983;Winicov, 1991;Johnson and Smith, 1992), tomato (Rus et al, 2000), and rice (Lutts et al, 1999). Often plants regenerated from such systems fail to exhibit their salt tolerance when regenerated into whole plants or when grown in soil (Gonzales, 1994;Flowers, 2004).…”