Electrofusion of mesophyll protoplasts from two varieties of sugar beet, (Beta vulgaris L.)

Somatic hybridization between different plants through protoplast fusion represent an efficient experimental approach to produce genetically transformed plant species. Electrofution of mesophyll protoplasts in sugar beet was occurred to overcome the barriers faced breeding program of this economically industrial crop Protoplasts were successfully isolated from leave's mesophyll of two varieties of sugar beet (Beta vulgaris L.). Various enzyme solutions were assessed for the cell wall degrading ability. They express different efficiency in isolation of mesophyll protoplasts of var. Baraka. The protoplasts yield was 18 × 104 cell ml-1 using the mixture consisting of 0.5% Cellulase RS, 1.0% Hemicellulase and 0.1% Pectolyase Y-23 with 13% mannitol. A total of 16 hrs. for cell wall digestion, and protoplast viability approached 93%. Protoplasts were isolated from leaf mesophyll of var. Carola using the same enzymatic mixtures. High protoplasts yield 20 × 104 cell ml-1 was obtained, requiring the same period 16 hrs. to approach viability 96%. The protoplasts were spherical in shape, varied in chloroplast distribution, having size ranged 12 – 52 µm. The present study succeeded in electrofusion between Baraka × Carola mesophyll protoplasts, producing somatic hybrid cells under conditions of 1MHz, 1000 Vcm-1, 2 pulses, 1.5 msec./pulse with fusion percent of 73%.