Cryopreservation Of Shoot Tips Of The Main Potato Cultivars In Inner Mongolia By Vitrification

Potato(Solarium tuberosum L.) belongs to the nightshade family, is the largest stample crop in the world. Recent development of vitrification is the most secure and best method for long-term preservation of germplasm resources. Shoot apical meristem has been recognized as an ideal material cryopreservation. Shoot-tips cryopreservation by vitrtification of four potato cultivars in Inner Mongolia:Kexinl, Zihuabai, Favorita, Holland potato91, designed to discuss the effects of potato cryopreservation of shoot tips’relationship between the optimal combination through the orthogonal experiment. The major results are as follows:1. Shoot tips of four potato cultivars were successfully cryopreserved wih the virtification procedure. A suitable procedure was established as follows:shoot tips about10mm in length were precultured for3days on MS medium supplemented with0.5mol/L sucrose at4℃.Then the excised shoot tips of2～3mm were pretreated in loading solution for40min at room temperature, and then treated with PVS2at0℃60min.After changing with fresh PVS2;then put them into liquid nitrogen directly and conserved for at least1h. After being rapidly thawed in a water bath at40℃for90s, shoot tips were rinsed twice in a1.2mol/L sucrose solution for20min at room temperature and transferred onto MS medium supplemented with6-BA0.5mg/L+NAA0.1mg/L+GA30.5mg/L. After culturing in darkness for5days rinsed to exposure to the light.The heighest survival rate of the shoot tips reached to86.67%, and regrowth rate reached80%.2. The differences of cryopreservation between different potato cultivars were compared. The survival rate of four patato cultivars(Kexinl,Zihuabai, Favorita, Holland potato91)was86.67%、80.00%、76.67%and66.67%respectively, and regeneration rate was80%、73.33%、50%and56.67%respectively.