Cytogenetic characterization of Schinus terebinthifolius Raddi (Anacardiaceae) accessions from Rio Grande do Sul State, Brazil

摘要

Schinus terebinthifolius (Anacardiaceae), popularly known as red aroeira, occurs naturally in Argentina, Paraguay, Uruguay, and Brazil. It has medicinal properties and is one of the species most sought by avifauna, so it is useful in heterogeneous reforestation intended for the recomposition of degraded areas of permanent preservation. Information about chromosomes, from simple chromosome counting to detailed molecular cytogenetics, is relevant in systematic and evolutionary studies. This study aimed to perform chromosomal characterization of 22 accessions of S. terebinthifolius native to Rio Grande do Sul, aiming to verify the intraspecific variability in this species, besides the conservation and sustainable use of this species. For the determination of chromosome number, tissues of root tips were subjected to a cold pretreatment (+ 4 degrees C) for 18 h. Afterwards, the roots were fixed in Carnoy 3:1 (ethanol/acetic acid) for 24 h at room temperature and stored under alcohol (70%) under cooling. The slides were prepared by the squashing technique and stained with 2% acetic orcein. The chromosome number of S. terebinthifolius found in 22 accessions was 2n = 28, and these studied accessions do not exhibit intraspecific variability.