Poster: Genetics, Genomics, and Molecular Evolution
P15043: Low co-cultivation temperature at 20oC improved Agrobacterium tumefaciens-mediated transformation of tobacco leaf disks
Murai, Norimoto Contact Presenter||Authors||Murai, Norimoto (A) Su, Guiying (A) Park, Sunjung (A) Lee, Seokhyun (A) |
(A): Louisiana State University and LSU Agricultural Center|
The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Nicotiana tabacum L. cv. Xanthi (nn, Smith) leaf disks. We compared the effect of temperatures ranging from 15, 18, 20, 22 to 25oC on the stable expression of β-glucuronidase (GUS) activity of 14 days old hygromycin-selected leaf disks, and on the increase in the fresh weight yield of 28 days old kanamycin-selected calli.
The highest average of GUS activity was obtained at 20oC among the five temperatures tested although the differences among the 18, 20, and 22oC treatment were not statistically significant. The lowest average of GUS activity was observed at 25oC. The GUS activity in 15oC treatment was an intermediate between the highest and lowest averages, and was not statistically significantly different. We concluded that co-cultivation at 20oC is the most effective condition for the stable expression of maximum GUS activity after transformation of tobacco leaf disks.
The highest increase in the plate average of fresh weight yields was obtained at 20oC among the five temperature tested. The 20oC treatment was statistically significantly better than the 15 and 18oC treatments. The 20oC co-cultivation treatment resulted in the higher FW yield than 22 and 25oC even though the differences were not statistically significant. We concluded that low co-cultivation temperature at 20oC under the most physiologically relevant conditions is the most critical determinant for the reproducible maximum increase in both the fresh weight yield and stable expression of GUS activity after transformation of tobacco leaf disks.