Tropentag, October 5 - 7, 2004 in Berlin "Rural Poverty Reduction through Research for Development and Transformation"

Dry Synthetic Seed Production and Desiccation Tolerance Induction in Somatic Embryo of Sweet Pepper

¹Chiang Mai University, Department of Agronomy, Thailand
²Georg-August-Universität Göttingen, Institute of Agricultural Chemistry, Germany

Abstract

The conventional hybrid seed production of sweet pepper (Capsicum annuum L.) is a long process with various problems of interspecific incompatibility andhigher number of F1 hybrid sterile. Synthetic seed technology may be of value in breeding programs and allow the propagation of many elite genotype-derived plants in a short time. The ability of somatic embryos to withstand drying to low moisture contents is important for storage, and plays a big role in the developmental transition between maturation and germination. Nodular, friable, and yellowish sweet pepper embryogenic callus developed from mature zygotic embryos cultured on MS (Murashige and Skoog) agar basal medium supplemented with 3 mg/l 2,4-D and 3 percent sucrose under light condition. Somatic embryos were induced and achieved by using embryogenic cell suspension culture in liquid MS basal medium, which supplemented with 1 mg/l 2,4-D and 3 percent sucrose. Somatic embryos at the torpedo stage were subjected to various different treatments in order to achieved increase somatic embryos desiccation tolerance. The treatments were exogenous applications of abscisic acid (ABA) in various concentrations (0.1-2.0 mg/l). It was found that somatic embryos which treated with 0.5 mg/l concentration of ABA for 20 days before encapsulated with 3% sodium alginate, and dehydrated in the laminar flow hood until 80 percent water loss still remained germinated to 58 percent. Furthermore improvements of dry somatic embryos can be accomplished by adding 60 g/l sucrose in the maturation medium, which resulted 40 percent of plantlets conversion after 4 weeks of storage in ambient temperature. The poor success number of viable synthetic seedling from this experiment showed that there is still some more researches needed in enhancing seedling vigorous in order to achieved better of survival germinated seedling.

Keywords: Capsicum annuum, desiccation tolerance, sweet pepper, synthetic seeds

Contact Address: Phonphat Phonkajornyod, Chiang Mai University, Department of Agronomy, Chiang Mai, Thailand, e-mail: phonphat_pyahoo.com