Field Behavor, Genetic Integrity And Biochemical Compound Assessments In Plants Of Chrysanthemum Morifolium Hangju’ After Cryopreservation, And Cryopreservation Of Transgenic Torenia Fournieri

Plant Germplasm is an prerequisite for breeding of new varieties. Due to deteriorating environments and human errors, plant germplasm has been seriously threatened. Therefore, conservation of plant germplasm is very important. Cryopreservation. has been considered to be an ideal.means for long-term conservation.Chrysanthemum morifolium ‘Hangju’ is an important medicinal plant in China. We previously reported successful cryopreservation for this plant. The present study further evaluated field performance, genetic stability and analyzed biochemical compounds in greenhouse-grown plants recovered from cryopreservation. Torenia fournieri is an important ornamental flower and is also a model plant for transgenic research. In this study, a cryopreservation was described for shoot tips of transgenic T. fournieri. Mormorlogies and foreign gene in plants regenerated from cryopreservation were analyzed. The main results are summarized as followings.1. Plantlets regenerated from cryopreservation were grown in the greenhouse conditions, for vegetative and reproductive growth. Although some minor alternations were detected in vegetative growth, including mean length of lateral stems and number of nodes of lateral stem, major parameters of vegetative growth were unchanged. Morphologies of leaves and flower, and reproductive ability were maintained the same in the plants regenerated from cryopreservation and control. Assessments by ISSR and RAPD markers did not find any polymorphic bands, and by FCM did not detect alternations at ploidy levels, in the plants recovered from cryopreservation. Analysis of UPLC-MS/MS showed that types and number of biochemical compounds were identical in the plants derived from cryopreservation and control. Quantitative determination by HPLC revealed contents of the 5 selected biochemical were the same between the two types of plants.2. Transgenic T. fournieri shoot tips were used as materials to optimize the key factors influencing cryopreservation and established its cryopreservation system. Shoot tips(2.0 mm in size) were excised from the 4-weeks old in vitro shoots of transgenic T. fournieri and precultured on MS solid medium containing 0.5 M sucrose for 1 day. Precultured shoot tips.were treated.with loading solution. for 20 min at.room temperature. Loaded. shoot tips were dehydrated. with plant vitrification. solution(PVS2).for 30 min at. 0 oC and made.into droplets. containing a shoot.tip on aluminium. foils, then put.the aluminium.foils in liquid nitrogen(LN).for 1 h. Frozen.foils with shoot.tips were immediately. put into unloading.solution for 20 min at room temperature. Thawed shoot tips were cultured on.shoot recovery. Medium(SRM) composed.of MS containing. 0.1 mg L-1 NAA. under dark.condition for.3 days, Then. shoot tips.were transferred.to the same.medium under. standard light.conditions for.shoot recovery. After 4 weeks of post-culture, plantlets were developed from cryopreserved shoot tips. No polymorphic bands were detected by ISSR markers in the plants recovered from cryopreservation. Analysis by PCR showed that cryopreservation did not change expression of the Cry1 Ab, and did not alter morphologies of transgenic T. fournieri...