Effect of salt stress on anatomical features of Lycopersicum esculentum M. and Capsicum annuum L.

Abstract

Salinity soil causes a constant threat to the survival of vegetable crops, particularly tomatoes and sweet pepper. Thus, choosing adaptive or saline-bearing items is the best solution. The aim of this study was to know the mechanism of adaptation and sensitivity to saline stress during the seedling phase. So, we designed two experiments for two types of sweet pepper vegetables Capsicum annuum L. variety Marconi and tomatoes Lycopersicum esculentum M. variety Berner rose treated with three different saline concentrations 2.5-5-10 g/l of NaCl in addition to the witness. After the seedlings reached the seven-sheets stage, an anatomical study was conducted on the stems of these two species to determine the effect of saline stress on the anatomical composition of the stems. After coloring the sections with double coloring, the samples were observed. The layers thickness was measured with a special camera type OPTICA Vision Lite 2.1 (2009) which was connected to a photomicroscope and a computer. Stems microscopic study demonstrated that salinity stress significantly decreased epidermal layer, hypodermal, pericycl, vascular cambium and pith area. In addition to an increase in the endodermal layers and the cells size in general, the lack or absence of space between cells, especially in high salt concentration (10 g/l) was also noticed. The present observations indicate tested tomato variety exhibited a resistant behavior compared to the sweet pepper plant, which exhibited a semi-sensitive behavior.