Identification des sources de tolérance au stress hydrique sur des espèces sauvages de la famille des Cucurbitacées en cutlture in vitro

Identification of tolerance sources to the water stress on wild species of the cucurbitaceous family in in vitro culture. The objective of this survey is to identify sources of tolerance to the water stress. This will permit to choose the adequate material allowing the transfer of genes governing the drought tolerance to the gene pool of the main cultivated species. Indeed, a method has been developed to evaluate the water stress tolerance in vitro. It is based on the capacity of the calus recuperation after dehydration under a laminar flux hot until a loss of 50% of their fresh weight as a basis. The study included nine accessions of wild species and three cultivated varieties of the cucurbitaceous family. It comes out that the three cultivated varieties (melon, cucumber and watermelon), as well as some wild species accessions are sensitive to the water stress. The wild accessions of Cucumis africanus (L4), Cucumis dipsaceus, Citrullus colocynthis (Saudi Arabia) and Citrullus colocynthis (Niger) are obviously tolerant.