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 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Evaluation of Constitutive Promoters for Gene Expression in Dendrobium Protocorms and Flowers) ผู้เขียน: Chidchanok Suwannaketchanatit, พรสุข ชัยสุข, Jitraparn Piluek,  ดร.สุรินทร์ ปิยะโชคณากุล, รองศาสตราจารย์ , พัฒนา ศรีฟ้า ฮุนเนอร์ สื่อสิ่งพิมพ์:pdf AbstractActively dividing protocorms of Dendrobium Jaquelyn Thomas orchid were produced on VW medium and transferred to 1/2 MS medium before subjecting to particle bombardment to evaluate the promoter efficiency. Three different constitutive promoters, rice Act-1, CaMV35S, and maize Ubi-1, were determined for the efficiency to control spatial transgene expression in protocorms and sepal tissues of Dendrobium orchid. Each promoter was fused to b-glucuronidase (uid A) gene and nos terminator in the plant expression vectors including pActin1-D, pAHC27, and p2K7. The plasmid vectors were individually bombarded into protocorms and fresh sepals of Dendrobium. Transient gus gene expression was assayed after 3 days of bombardment. The results demonstrated that all tested promoters could drive gus gene expression in the orchid protocorms at different levels. Ubi-1 promoter conferred the most efficient promoter in protocorms giving the highest level of gus gene expression, whereas GUS activity was distinctly observed under the control of Act-1 and CaMV35S in the Dendrobium sepal tissues. Both Act-1 and CaMV35S promoters performed well in the vascular tissue of flower as opposed to the Ubi-1 promoter that did not perform in flower. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effect of Sucrose and ABA on Survival Rate of Cryopreserved Protocorms of Dendrobium gratiosissimum Rchb.f.) ผู้เขียน:Sumontip Bunnag, Praweena Maneerattanarungroj, Anawat Suwanagul สื่อสิ่งพิมพ์:pdf AbstractDendrobium gratiosissimum Rchb.f. is a rare wild orchid. Cryopreservation is an alternative and important tool for ex situ preservation of orchid germplasm. In this study, protocorms of D. gratiosissimum were induced and cultured on solidified New Dogashima (ND) medium containing 0.3 mg/l NAA for two months. These protocorms were used as explants in cryopreservation using an encapsulation – dehydration method. For treatment with ABA, encapsulated protocorms were precultured in liquid ND medium containing various concentrations of ABA made up of 0, 0.01, 1 and 10 mg/l. For the sucrose treatment, beads were precultured in a semi-solid ND medium containing 0.25 M sucrose in the dark for one week at 4oC and then transferred into liquid ND medium containing 0, 0.5, 0.75 and 1 M of sucrose and then cultured for two days before dehydration. The highest percentage regrowth of cryopreserved explants was observed when precultured in the liquid ND medium supplemented with 1 mg/l ABA for one week and then dehydrated with silica gel in a laminar air-flow for five hours prior to immersion in liquid nitrogen for one hour. Regrowth ability testing performed after two weeks of treatment produced a rate of regrowth of 67% ? 0.5. Consequently, a simple and reliable protocol for the cryopreservation of D. gratiosissimum was clearly revealed in this study. |
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