Effet de l’Acide Gibberellique sur la germination et de l’Acide Salicylique sur la teneur en Proteines de Prunus Africana (Hook.f.) Kalkam (Rosaceae)

Abstract

Prunus africana (Rosaceae) is an endemic tree species in Africa operated primarily for its bark for medicinal virtue. This species is threatened with extinction because of its abuse. Moreover germination of this specie under natural conditions is difficult, due to the fibrous seed endocarp. In this experiment, the issue was to evaluate the effect of gibberellic acid (GA 3) on seed’s germination and also to evaluate the effect of salicylic acid on the protein content during development of the seedlings of P. africana. Germination of seeds of P. africana has been made in media containing GA3 (at 0; 10; 50 and 100 mM). GA3 at 10 mM yielded shorter germination period (3 days). This concentration induces a seedling meristem elongation higher than the control (37%). After transfer onto solid substrate soil / sawdust, seedlings treated with salicylic acid (at 0; 2x10-7; 20x10-7 and 200x10-7 M) have observed a significant change in the total protein content according to the organs studied. Although the evolution of the content of these compounds is similar in the roots and leaves, there is a significant decrease in this parameter after 3 weeks of treatment in each organ. At contrary in the shoot, only 200 x 10-7 M salicylic acid allows a significant increase in soluble protein content after 2 weeks compared to the others treatments, according to our results. This could suggest the important role of salicylic acid in metabolic reactions requiring the use of protein molecules in plants to allow better adaptation in the post-germination stages. As only seedlings not previously treated with GA3 was used to post - germination treatment with salicylic acid we should consider it as favorable for plant development.