Growth Inhibition of In Vitro Plantlets and Improvement of Survival Rate of Acclimated Plant of Strawberry according to Polyethylene Glycol during Bioreactor Culture

This study was carried out treatment of polyethylene glycol (PEG) in order to increase of survival rate of acclimated plants of strawberry's in vitro plantlets through bioreactor culture. We used PEG with molecular weight 6000 (PEG 6000) in this study. Concentration of PEG is non-treatment, 5, 10, 15, and $20g{\cdot}L^{-1}$ each bioreactor. $5g{\cdot}L^{-1}$ of PEG was treated at $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$, and $5^{th}$ week during culture. We investigated growth characteristics of in vitro plantlets after 6 weeks cultivation. Growth amount of all PEG treatment decreased as compared to non-treatment. The more concentration increased, the more plant growth decreased. In $5g{\cdot}L^{-1}$ of PEG, shoot length was shorter than non-treatment that shoot length was 7.9 cm and especially fresh weight that is 1.6 g was more decrease than non-treatment. Shoot length was ranged 3.0-3.9 cm at $1^{st}$ week treatment to $4^{th}$ week treatment of $5g{\cdot}L^{-1}$ PEG. The shoot length was not significant by 5.3 cm at $5^{th}$ week treatment. The survival rate was improved 5.4% at the treatment of $4^{th}$ week and was improved 8.7% at the $5^{th}$ week as compared to non-treatment. In order to improve of survival rate of strawberry' in vitro plantlets through bioreactor culture, the method is suitable that adding $5g{\cdot}L^{-1}$ of PEG in the medium and $5^{th}$ week's treatment is suitable.

딸기 조직배양묘의 생물반응기 배양 시 Polyethylene Glycol 처리에 따른 기내 생육억제 효과 및 순화율 향상

본 실험은 생물반응기를 이용한 딸기 조직배양묘의 대량증식 시 순화 생존율 향상을 위하여 polyethylene glycol(PEG 6000)을 농도별, 처리시기별로 실험하였고 기내생육조사는 배양 6주 후에 실시하였다. 모든 PEG처리구의 생장량은 대조구에 비해 매우 감소하였고, 농도가 높아질수록 생장억제 효과가 급격히 나타났다. PEG $5g{\cdot}L^{-1}$처리 시 초장은 대조구의 7.9cm보다 매우 짧아졌고, 특히 생체중은 1.60g으로 대조구보다 감소하였다. PEG $5g{\cdot}L^{-1}$의 배양1주차에서 4주차까지의 처리시 초장이 3.0-3.9cm 범위로 대조구보다 매우 짧았으나, 배양5주차 처리의 초장은 5.3cm로 큰 차이를 보이지 않았다. PEG $5g{\cdot}L^{-1}$의 처리시기별 순화 생존율은 대조구에 비해 배양4주 처리에 5.4%, 배양5주차 처리에 8.7% 향상되었다. 따라서 생물반응기를 통해 대량증식된 딸기 조직배양묘의 순화율 향상을 위해 PEG는 $5g{\cdot}L^{-1}$의 농도로 배양 5주차에 처리하는 것이 적당하였다.