SELECTION OF DROUGHT TOLERANCE OLIVE PLANTS

Abstract

ABSTRACT

The current study was carried out to investigate the effect of low wate potential generated by polyethylene glycol (PEG 6000) on growth of in vitro propagated ‘Manzanillo’ olive cultivar and to identify possible molecular marker for drought tolerance. The response of ‘Manzanillo’ olive cultivar to in vitro multiplication was studied on Rugini olive and Murshige and Skoog media with three zeati concentrations. Different levels of water stress were induced using fou concentrations of PEG 6000 (0, 2.5, 5 and 7.5%).

The obtained results showed that nutrient media and zeatin concentrations hav a slight effect on sprouting% of Manzanillo olive. Plants grown on OM medium recorded higher multiplication rate, leaves number/shoot and shoot length compared with MS media. There was an obvious difference between the used zeatin regarding the shoot length and leaves number/shoot. Plants grown on rooting medi supplemented with IBA 2 mgL recorded higher rooting percentage compared wit rooting media supplemented with NAA 2 mgL -1 while the combination of the tw auxins gave intermediate results. Regarding water stress treatments; survival percentage decreased graduall with increasing PEG in growth media. The evaluation of growth reveals a significant reduction in plants length, shoot fresh weight, moisture percentage and chlorophy pigments of drought stressed plants. Water stress increased defoliation percentag and leaves proline content. Protein profile in olive shoots has been changed unde drought stress. Protein profile of stressed and non-stressed plants showed the presence of five protein types. Plant length, leaves number and defoliation percentage showed a high variation among the selected olive seeds (Manzanillo).

-1