Shin Jong Hee, Kang Dong Kyoon, Sohn Jae Keun
Gyeongbuk Provincial Agricultural Technology Administration, Daegu, Republic of Korea.
Cryo Letters. 2013 Mar-Apr;34(2):149-57.
In the present study, Yam mosaic virus (YMV) could be efficiently eliminated by cryotherapy in Dioscorea opposita. Shoot apices were precultured for 16 h with 0.3 M sucrose, encapsulated in sodium alginate and dehydrated for 4 h prior to direct immersion in liquid nitrogen. Up to 90 percent of the plants regenerated from cryopreserved shoot tips were YMV-free, whereas only 40% of those regenerated using meristem culture were YMV-free. YMV-free yam plantlets could be propagated in vitro through nodal stem culture, with sequential subculturing at 6-week intervals on medium containing 0.5 mg per liter kinetin. The microtubers formed at the bottom and axil of the explants, incubated at 30 degreeC after being chilled (4 degree C) for 3 months, could be sprouted successfully under in vivo conditions. Healthy plants were established without any damaging symptoms of the virus. Thus, cryotherapy provides an alternative method for efficient elimination of yam viruses, and could be simultaneously used for long-term storage of yam germplasm and for the production of virus-free plants.
在本研究中，山药花叶病毒（YMV）可通过冷冻疗法在山药中有效消除。茎尖用0.3M蔗糖预培养16小时，包埋于海藻酸钠中，在直接浸入液氮前脱水4小时。从冷冻保存的茎尖再生的植株中，高达90%无YMV，而采用分生组织培养再生的植株中只有40%无YMV。无YMV的山药组培苗可通过茎节培养进行离体繁殖，每隔6周在含有0.5毫克/升激动素的培养基上继代培养。外植体底部和腋部形成的微型块茎，在4℃冷藏3个月后于30℃培养，可在体内条件下成功发芽。建立了无任何病毒损伤症状的健康植株。因此，冷冻疗法为有效消除山药病毒提供了一种替代方法，并且可同时用于山药种质的长期保存和无病毒植株的生产。
