In vitro cultivation of <i>Anacardium othonianum</i> Rizz.: Effects of growth regulator, explant orientation and lighting

Abstract

Anacardium othonianum Rizz. is a Brazilian savannah native species, commonly known as caju-deárvore- do-cerrado. Its usual reproduction is by seeds or asexually; however, its use in forest programs or for commercial orchards demands continuous and large scale seedling production. This study evaluated the effect of naphthaleneacetic acid (NAA) and 6-benzylaminopurine (BAP), the position of the explants and the effect of lighting in the regeneration of A. othonianum Rizz. stem segments. The Murashige and Skoog medium (MS) medium was used in the first test, amended with nine combinations of NAA (0, 5.37 and 10.74 μM) and BAP (0, 4.44 and 8.88 μM) in a completely randomized design. While the second test was arranged as a 2 × 2 factorial, evaluating the orientation of the explants (upright or horizontal) and incubation condition (absence or presence of light). The number of buds, the number and average length of leaves and the number of plantlets were evaluated after 30 and 60 days of growth. The results obtained indicate that the concentrations of BAP and NAA used had no effect on the multiplication of A. othonianum Rizz. stem segments, and the best morpho-physiologic in vitro response was obtained with horizontal segments in the presence of light.

Key words: Growth medium, micropropagation, savannah plants.