Since in vitro regeneration and transformation systems in hot pepper (Capsicum annuum L.) have not been available, the application of new genetic manipulations has been limited. Here we report an efficient procedure to regenerate whole pepper plants and to generate transgenic plants expressing a foreign gene was established. High frequency of plant regeneration was observed when hypocotyl and cotyledon explants were cultured on MS/B5 medium supplemented with NAA 0.05 mg·L–1 plus zeatin 2.0 mg·L–1, NAA 0.05 mg·L–1 plus zeatin 2.0 mg·L–1, IBA 10.0 mg·L–1 plus BA 1.0 mg·L–1, IAA 0.02 mg·L–1 plus zeatin 3.0 mg·L–1. An addition of AgNO3 5–10 μm to these media improved the regeneration rate by about 10%. For plant transformation, hypocotyl and cotyledon explants of pepper were preconditioned on kanamycin-free shoot induction medium for 48 hours. Then, co-cultivation with Agrobacterium tumeaacience was done on the co-culture medium for 2 days. The explants were then blotted in sterile filter paper and placed on shoot induction and selection medium containing kanamycin sulfate (100 mg·L–1) and carbenicillin (500 mg·L–1). PCR showed that the introduced ADA gene was integrated and stably expressed in the regenerated plants. ADA enzyme activities were checked by spectrophotometric analysis.
Hak-Tae Lim, Kei-youn Lee, Yeoung-Sook Yoo, and Duck-Chun Yang
Won Bae Kim, Kwan Soon Choi, Young Hyun Om, and Hak Tae Lim
In an attempt to obtain the basic data for the development of Hanabusaya asiatica as horticultural plants, studies were conducted on the habitat environment, ecological characteristics, various treatments for breaking seed dormancy, and morphological and flowering characteristics of H. asiatica at different growth stages. Hanabusaya asiatica was distributed around areas of 850–1400 m above sea level with an inclination of 5–43°. The vegetation structure of H. asiatica was represented in groups as Quercus mongolica and H. asiatica. In a subgroup, Symplocos chinensis v. leucocarpa for. pilosa, Magnolia sieboldii, and Acer mono were included. Indication species of Quercus mongolica and H. asiatica were Quercus mongolica (B1 layer), Tilia amurensis (B2 layer), Rhododendron schlippenbachii (S layer), Ainsliaea acerifolia v. subapoda, Athyrium nipponicum, Spuriopimpinella brachycarpa, and Carex siderostica (K layer). Soil pH was about 5.4, and soil fertility was relatively in a good condition. The optimum conditions for seed germination was at 25Y.