Excised leaf sections of lance coreopsis cultured on Murashige Skoog (MS) medium produced adventitious shoots in response to BA. When the combinations of 0, 0.5, 1, or 2 μm NAA with 0, 5, 10, 20, or 40 μm BA were tested, shoots were induced by any of the four BA concentrations used in the medium, regardless of the presence of NAA. The average number of shoots formed per leaf section ranged from 1.4 to 4.3 seven weeks after culture initiation. Roots were induced at the base of individual shoots on the same regeneration medium when cultures were kept longer than 7 weeks. The rooted plants were transferred successfully into soil. The regenerated plants had the same growth and flowering characteristics as the seed-grown plants. Chemical names used: benzyladenine (BA); naphthaleneacetic acid (NAA).
Chiwon W. Lee, Joel T. Nichols, Lijuan Wang, and Shanqiang Ke
Jing-jing Zhao, Xun Chen, Li-juan Fan, and Ling Wang
Lijuan Fan, Yu Gao, Karl H. Hasenstein, and Ling Wang
Chiwon W. Lee, Lijuan Wang, Shanqiang Ke, Mingbo Qin, and Zong-Ming Cheng
The phenotypic expression and inheritance of the rolC gene in the transgenic plants of Salpiglossis sinuata L. were investigated. The chasmogamous salpiglossis plants with solid yellow flower color (ccrrDD) were transformed with Agrobacterium tumefaciens strains LBA4404 and EHA101 carrying rolC, GUS, and NPTII genes via a leaf disc co-cultivation system. The transgenic plants were shorter in plant height, produced more branches with a compact growth habit, and developed smaller flowers and narrower leaves as compared to the control plant. While the transgenic plants showed the same corolla color and color shades as the parental line, they became male sterile. A backcross between a male-sterile transgenic plant (ccrrDD plus rolC) and a nontransformed red-flowering line (ccRRDD) produced a progeny with red flower color and the same altered growth habit as the transgenic female parent. Only 4 out of 32 plants in this progeny population showed the negative GUS staining as well as the non transgenic phenotype. These results suggest that at least two copies of the rolC gene were integrated into one homologous chromosome pair during transformation and that a cross-over event may have occurred during meiosis.
Lijuan Wang, Nian-Oine Shi, Murray E. Duysen, and Chiwon W. Lee
Cleistogamy in Salpiglossis sinuatu L. involves a sequence of events, including arrested corolla development, precocious pollen germination inside anther, pollen tube penetration of the pistil, and eventual self fertilization, that takes place. within a tightly closed flower bud. A single dominant gene (C) controls cleistogamy in this plant. During early blooming period, cleistogamous (CC, Cc) plants produce both chasmogamous (open) and cleistogamous (closed) flowers. Enzymes in various tissues of both cleistogamous and chasmogamous buds were detected by isozyme banding patterns in starch gel electrophoresis. The onset of cleistogamy may be signalled in the calyx and corolla tissues in the early stage of flower development. The levels of specific enzymes (PGM, PGI, G-6PD, PGD, MPI) involved in gluconeogenesis, pentose phosphate shunt and glycolysis in both calyx and corolla tissues of the cleistogamous buds were greatly reduced. These enzymes were present in the pistil and anthers of cleistogamous buds and in all floral parts of the chasmogamous buds.