In vitro production of potato microtubers in liquid medium using temporaryimmersion

CIRAD developed a new apparatus for plant tissue culture, using temporary i mmersion in a liquid medium. This apparatus was adapted to the microtuber p roduction in potato. The procedure is as follows: single node cultivation o n MS medium containing 30 g/l sucrose in the light for 2 weeks, induction o f microtuberisation with 80 g/l sucrose over a 2 week period in the light, followed by a further 6 weeks in the dark. All experiments were performed a t 20 degreesC. The basic vessel had a capacity of approximately 11; 30 node s were cultivated per vessel. Depending on the cultivars tested (Bintje, Os tara and Desiree) 47 to 115 microtubers were harvested per vessel. Between 30 and 60% of the microtubers weighted over 0.5 g and between 10 and 40% ov er 0.8 g. Sprouting is still under investigation. Preliminary results indic ate that the dormancy period was relatively short and several stems were ob tained per microtuber. These results seem to be better than those usually r eported. Only one simple protocol has been tested and further improvements are probably easy to obtain.