Abstract

ANDRESSEN, Diana et al. Optimization of the in vitro proliferation of jojoba (Simmondsia chinensis (Link) Schn.) by using rotable central composite design and inoculation with rhizobacteria. Bioagro [online]. 2009, vol.21, n.1, pp.41-48. ISSN 1316-3361.

Jojoba (Simmondsia chinensis (Link) Schn.) is a plant wich seeds produce oil of high commercial value used in cosmetology and as lubricant. Experiments were conducted using the rotable central composite design (RCCD) in order to get the optimum of its proliferation in vitro and to evaluate the effect of the plant growth-promoting rhizobacteria PGPR). Nodal segments were cultivated in Murashige & Skoog basal medium with different relations of sucrose (S) and 6- benziladenin (BA), calculated by the RCCD. According to the response surface graph, it was obtained that the optimun number of buds developed as shoots was 5.68, corresponding to 22.3/1.6 S/BA relationship. The biotization with 5 x 10⁶ cfu·bud^-1 of Azotobacter chroococum increased significantly the number of shoots generated per bud (rate of multiplication). In presence of 0.5 and 1 mg·L^-1 of BA, increments of 46 and 28 % were obtained, respectively. The inoculation with Azospirillum brasilense and A. lipoferum did not show any significative increase in the rate of multiplication.

Keywords : Micropropagation; Azospirillum brasilense; A. lipoferum; Azotobacter chroococcum; biotization.