STUDIES OF COTYLEDON PROTOPLAST CULTURES FROM BRASSICA-NAPUS, BRASSICA-CAMPESTRIS AND BRASSICA-OLERACEA .1. CELL-WALL REGENERATION AND CELL-DIVISION

Citation
Kn. Zhao et al., STUDIES OF COTYLEDON PROTOPLAST CULTURES FROM BRASSICA-NAPUS, BRASSICA-CAMPESTRIS AND BRASSICA-OLERACEA .1. CELL-WALL REGENERATION AND CELL-DIVISION, Plant cell, tissue and organ culture, 40(1), 1995, pp. 59-72
Citations number
40
Categorie Soggetti
Plant Sciences
ISSN journal
01676857
Volume
40
Issue
1
Year of publication
1995
Pages
59 - 72
Database
ISI
SICI code
0167-6857(1995)40:1<59:SOCPCF>2.0.ZU;2-W
Abstract
Protoplasts isolated from cotyledons of a number of cultivars of Brass ica napus, B. campestris and B. oleracea were cultured in different me dia to study the characteristics of cell wall regeneration and cell di vision at early stages of culture. Time course analysis using Calcolfl uor White staining indicated that cell wall regeneration began in some protoplasts 2-4 h following isolation in all cultivars. 30-70% of cul tured cotyledon protoplasts exhibited cell wall regeneration at 24 h a nd about 60-90% at 72 h after the initiation of culture. Results also indicated that a low percentage (0.4-5.4%) of cultured cotyledon proto plasts entered their first cell division one day after initial culture in all twelve cultivars. The percentage of dividing cells increased l inearly up to 40% from 1 to 7 day, indicating that cotyledon protoplas ts of Brassica had a high capacity for cell division. Factors that inf luence the level of cell wall regeneration and cell division during co tyledon protoplast culture have been investigated in this study. Cotyl edons from seedlings germinated in a dark/dim light regime provided a satisfactory tissue source for protoplast isolation and culture for al l Brassica cultivars used. The percentages of protoplasts exhibiting c ell wall regeneration and division were significantly influenced by cu ltivar and species examined, with protoplasts from all five cultivars of B. campestris showing much lower rates of cell wall regeneration th an those of B. napus and B. oleracea over 24-120 h, and with the level s of cell division in B. napus cultivars being much higher than those in B. campestris and B. oleracea over 1-9 days. The capacity of cell w all regeneration and cell division in cotyledon protoplast culture of the Brassica species appears under strong genetic control. Cell wall r egeneration in protoplast culture was not affected by the culture medi um used. In contrast, the composition of the culture medium played an important role in determining the level of cell division, and the inte raction between medium type and cultivars was very significant.