In vitro chili pepper biotechnology

Abstract

Chili pepper is an important horticultural crop that can surely benefit from plant biotechnology. However, although it is a Solanaceous member, developments in plant cell, tissue, and organ culture, as well as on plant genetic transformation, have lagged far behind those achieved for other members of the same family, such as tobacco (Nicotiana tabacum), tomato (Lycopersicon esculentum), and potato (Solanum tuberosum), species frequently used as model systems because of their facility to regenerate organs and eventually whole plants in vitro, and also for their ability to be genetically engineered by the currently available transformation methods. Capsicum members have been shown to be recalcitrant to differentiation and plant regeneration under in vitro conditions, which in turn makes it very difficult or inefficient to apply recombinant DNA technologies via genetic transformation aimed at genetic improvement against pests and diseases. Some approaches, however, have made possible the regeneration of chili pepper plants from in vitro-cultured cells, tissues, and organs through organogenesis or embryogenesis. Anther culture has been successfully applied to obtain haploid and doubledhaploid plants. Organogenic systems have been used for in vitro micropropagation as well as for genetic transformation. Application of both tissue culture and genetic transformation techniques have led to the development of chili pepper plants more resistant to at least one type of virus. Cell and tissue cultures have been applied successfully to the selection of variant cells exhibiting increased resistance to abiotic stresses, but no plants exhibiting the selected traits have been regenerated. Production of capsaicinoids, the hot principle of chili pepper fruits, by cells and callus tissues has been another area of intense research. The advances, limitations, and applications of chili pepper biotechnology are discussed.

Direct shoot regeneration via organogenesis in chieh-qua (Benincasa hispida Cogn. var. Chieh-qua How)

“…However, some problems were encountered, such as the formation of ill-defined buds and shoot-like structures either resisting elongation or producing rosettes of distorted leaves, which generally do not produce normal shoots. Similar problems have been observed in melon (Gaba et al, 1999) and pepper (Steinitz et al, 1999;Ochoa-Alejo and Ramirez-Malagon, 2001). These problems may be linked to genotypes or the medium for shoot regeneration.…”

An Immunological Investigation of Leaf Development in Capsicum frutescens

“…Solanaceae members such as L. esculentum (tomato), N. tobaccum (tobacco) and S. tuberosum (potato) are the model systems have been subjected to biochemical and immunological investigations (Ochoa-Alejo & Ramirez-Malagon, 2001). Advanced techniques such as genetic transformation, genetic modification can improve the crop qualities and these crop cells are capable of regenerating organs by cell, tissue and organ cultures and eventually to a whole plant in vitro.…”

Induction of in vitro flowering in Capsicum frutescens under the influence of silver nitrate and cobalt chloride and pollen transformation

“…Capsicum is highly recalcitrant species and there are lots of variations with in the species for their response in tissue culture studies (Ochoa-Alejo and Ramirez-Malagon, 2001). Especially in C. annuum different cultivar varieties that are specific to geographical locations show significant variations morphologically for growth and even pungency.…”

“…Mild and high pungent varieties of peppers are used for the fresh market and for processing while those of the low pungent varieties are used for production of oleoresin and additives. Even though other Solanaceae members easily undergo morphogenesis, chili was found to be highly recalcitrant (Ochoa-Alejo and Ramirez-Malagon, 2001). Application of cell and molecular biology techniques for genetic improvement has been limited because of the difficulties in plant regeneration (OchoaAlejo and Ramirez-Malagon, 2001).…”