Morphological and anatomical characterization of six jojoba clones at saline and non-saline sites

Abstract

Various jojoba ( Simmondsia chinensis (Link) Schneider) clones have been demonstrated to differ in their susceptibility to salinity in northern Chile. Our objective was to characterize the anatomical and morphological response of six of these clones when grown under saline and non-saline conditions. Two of these clones are resistant to soil salinity (4.11.32 and Mirov), based on previous field evaluations, and four are susceptible (5.1, AT1487, 2.1 and 4.8). For each clone, three 2-year-old plants were planted at three locations in Chile. The Las Cardas Experimental Station is non-saline (soil EC=2 dS m −1), and the Quebrada de Camarones and Villa Frontera sites are saline (soil EC=38 and 63 dS m −1, respectively). Significant differences were found among clones at each site for several morphological and anatomical parameters studied, including number and size of stomata, density of trichomes, leaf size, branching characteristics and stem diameter. In general, plants grown under high salt levels did not show much difference from those grown under non-saline conditions for most of the morphological and anatomical parameters measured. Only leaf and cuticle thickness showed a high tendency to increase under saline conditions. The two resistant clones did not show consistent differences from the susceptible clones. However, the most salt-resistant clone (4.11.32) had the lowest stomata and trichome density and the largest stomatal size.