SOMACLONAL VARIATION OF Phanaenopsis sp. var. Dudu PLANTS REGENERATED BY DIRECT SOMATIC EMBRIOGENESIS

Abstract

Background: Nowadays, a growing demand for hybrids of Phalaenopsis sp. exists to satisfy this demand it is necessary to develop protocols for massive propagation that ensure high percentages of clonal regeneration, such as somatic embryogenesis. Besides, studying genetic variation within regenerated plants offers a greater understanding of the suitability of the micropropagation protocol in relation with genetic stability of the materials used. Objective: The present research work aimed to evaluate three concentrations of two types of plant growth regulators (RCV). 6-benzylaminopurine cytokinin (BA) (1.0, 2.0 y 3.0 mgL-1) in combination with three concentrations of 2,4-diclorofenoxiacetic acid (2,4-D) (3.0, 4.0, 5.0 mgL-1), for the induction of somatic embryos. In addition, the genetic stability of the regenerated plants was analyzed using molecular markers type RAPD (Random Amplified Polymorphic DNA). Methodology: The induction of somatic embryogenesis was induced from two leaf explants with different stages of develop from 15-20 cm in height Phalaenopsis sp. var. Dudú seedlings, cultivated in vitro; first leaf as mature explant (PH) and third leaf as young explant (TH). Results: The highest number of regenerated plants was 29.8 at 135 days after the start of the culture (ddic) with 2.0 and 5.0 mgL-1 of BA and 2,4-D, respectively, using TH as explant. In the morphogenetic response of the regenerated explants, a correlation was observed between the age of the explant and the RCV concentration. Polymorphic bands were observed with the four primers used, indicating somaclonal variation in regenerated plants. Implications: The results obtained provide an alternative for regeneration, as well as offering a methodology to initiate genetic improvement programs in Phalaenopsis sp. var. Dudú. Conclusions: In vitro regeneration of Phalaenopsis sp. var. Dudú by somatic embryogenesis was achieved, as well as the analysis of the genetic integrity of the regenerated material.

Keywords

• phalaenopsis sp.
• protocorm like bodies (plb´s)
• cultivo in vitro
• variación genética
• ácido 2,4-diclorofenoxiacético
• 6-bencilaminopurina
• amplificación aleatoria de polimorfismo de adn (rapd).