Growth in Tissue Culture of Single-Cell Clones From Grape Stem & Phylloxera Gall.

Information about the behavior of clones of plant tissue of single-cell origin is valuable for our understanding of diseased and normal cell growth. Questions appeared about the variability of the cells in the insect-induced galls. Perhaps only a few diseased cells were responsible for the mass of abnormal, rapidly increasing cells, and the majority of the other cells provided a favorable nutritional and physical environment. A large number of single-cell cultures from the mother callus strains of both the normal grape stem tissue and gall tissue incited by Phylloxera vastatrix Planch, were available for study of cell variability (8). Increase in wet weight of the tissue culture resulted from the cell division and growth of the cellular mass, and indicated the degree of the activity of the tissues. Differences were observed in the fresh weight of the clones after 4 to 5 weeks of growth of both the normal and diseased clones when grown on basal mineral salts, 2.0 % sucrose agar medium, supplemented with coconut milk (CM) and additional growth promoting substances including alpha-naphthaleneacetic acid (NAA), calcium pantothenate, and 2,4-dichlorophenoxyacetic acid (2,4-D). The purpose of this study was to clarify the behavior of the selected clones at different periods of their development, and to compare the growth characteristics of the clones with cell counts and dry weight.