Some Morphological Aspects of Fruit Tissues Grown In vitro

Abstract

1. Tissue explants from nearly mature fruit pericarp grown in vitro on agar nutrient media show cellular proliferation over the upper exposed surface. 2. Internal growth may result from cambial-like activity near the upper or lower surfaces. 3. Binucleate and multinucleate cells may exist for short periods. These result from rapid nuclear division and subsequent slower wall development. 4. Continued cell division without much subsequent cell enlargement gives rise to isolated "prothalli" of small cells or long lines of small cells within the mother-cell wall. 5. Tracheid cell types of various forms and sizes appear in older cultures especially where cambial activity has occurred. 6. Anthocyanin pigments may appear at random near the upper surface of actively growing avocado tissue in vitro. Conspicuous ergastic materials are apparently lacking in proliferating tissues.