Potato (Solanum tuberosum L.) is one of the crops that could be maintained and multiplied by vegetative procedures, including micropropagation through in vitroculture of meristems and plantlets.
For in vitroconservation is used the slow growthmethod. The aim is to limit the growth of plantlet developed from minicuttings, resulting in a prolonged duration between two subcultures, along with an improvement in survival of biologic material.
Slow growth media in combination with temperature decreasing in the conservation room were tested.
Photo 1. Aspect from the conservation room of the potato varieties collection
Photo 2. Detail of the minicuttings development, depending on culture medium and genotype
Photo 3. Detail of the minicuttings development, depending on culture medium and genotype
In the collection of Solanum tuberosum, regenerated through in vitro meristem culture, there are 82 local potato genotypes, originating in Romania.
As a result of international bilateral projects in the collection were added two varieties of Solanum tuberossum ssp andigena received from Hungary and three potato varieties brought from China.
For this moment the conservation conditions of plantlets (24 - 39 months), could be synthesized as below:
- 1/2 MS medium;
- low content of growth regulators;
- 3-5% manitol or sorbitol or 30â€“35 mg/l daminozide;
- 2% sucrose;
- photoperiod 10 h /24 h:
- light intensity/ 1000 lx;
- temperature: 7 to 10Â°C;
- 20 plantlets per culture medium;
- 60 plantlets per genotype;
Photo 4. Aspects of in vitro development of potato genotype SVGB-16115 (Gura Vaii - Brasov County), in slow growth conditions, during 38 months
Microtubers, regenerated in the micropropagation process are also stored at low positive temperatures.
Preservation conditions for microtubers (10 -12 months) are:
- 24 h dark;
Photo 5. Phenotypic variability of microtubers, regenerated during the micropropagation phase, of potato collection