TECHNIQUE TO STUDY THE INTERNAL MICROMORPHOLOGY OF HARD SEEDS IN Opuntia

Abstract

The study of internal morphology of hard seeds is a challenge, since it is difficult to section this kind of specimen. The present technique uses a lime to polish the seed until a median section in obtained. The polished surface is photographed under a stereomicroscope to obtain a digital image, which is studied using an image analysis software to get qualitative and quantitative data of the internal structure. Data can be submitted to several statistical analyses. Application of this technique is presented as an example in a comparative study of the seed micromorphology of 24 genotypes of Opuntia spp. which allowed to separate them in four groups. Group 2 showed genotypes with funicular seedcoat thinner in their ventral region. Group 3 showed genotypes with thinner funicular seedcoat in their dorsal region and Group 4 had ticker funicular seedcoat.