Starch gel electrophoresis and isoenzyme staining were studied in raspberry (Rubus idaeus L., R. X neglectus Peck, and R. occidentalis L.). Seven isoenzymes could be separated using one of two gel-electrophoresis buffers: tris-citric acid at pH 7.1 for aconitase (ACO), isocitrate dehydrogenase (IDH), phosphoglucomutase (PGM), and triose phosphate isomerase (TPI) and histidine-citric acid at pH 5.7 for malate dehydrogenase (MDH), phosphoglucoisomerase (PGI), and shikimate dehydrogenase (SKDH). There were no variations detected between samples obtained from micropropagated shoots, greenhouse-, or field-grown plants. Tissue type and age had no effect on isoenzyme banding patterns except for PGM where this affected the relative densities of the bands. Fifty-five out of 78 raspberry cultivars could be uniquely characterized using the above isoenzymes. Analysis of cultivars obtained from multiple sources detected occasional mislabelled plants. The mode of inheritance of raspberry isoenzymes was studied and analysis of co-segregating loci revealed two possible linkage groups: Mdh-2/Tpi-2/Pgm-1 and Idh-1/widh. / A high rate (70%) of adventitious shoot regeneration was observed from leaf-petiole explants of micropropagated shoot cultures of 'Comet' red raspberry cultured on modified Murashige-Skoog medium containing 1 mg/l thidiazuron (TDZ) and 0.5 mg/l 1H-indole-3-butanoic acid (IBA). Variation in the agar concentration or incubation temperature, orientation or scoring of the leaf-petiole explants and use of separate leaf or petiole explants had no effect on shoot regeneration while incubation in the dark for 1, 2, or 3 weeks prior to growth in the light depressed the number of adventitious shoots formed. Only 8 of 22 raspberry cultivars were capable of regenerating from leaf explants of greenhouse-grown plants.

No description available.