Plant growth regulators on the micropropagtion of Actinidia cultivars

Reguladores de crescimento vegetal na micropropagação de cultivares de Actinidia

ABSTRACT

Actinidia Lindl., commonly known as kiwifruit, is a valuable berry crop. The area of commercial kiwifruit plantations is increasing; the global production of kiwifruit is about 0.62% of the total production of major fruit crops. The use of biotechnological methods, which can significantly accelerate the propagation of quality planting materials, is considered to be relevant for the propagation of this crop. In this study, we optimized the culture medium composition at the micropropagation stage for the effective cultivation of promising cultivars of A. arguta, A. kolomikta, and A. polygama. We investigated the features of Actinidia morphogenesis depending on the genotype, the concentration of 6-Benzylaminopurine (0.5, 0.8, and 1.0 mg L^-1), and plant growth regulators (6-Benzylaminopurine, meta-topolin, and 2-isopentenyladenine at a concentration of 0.5 mg L^-1) in the media Quoirin and Lepoivre. Actinidia arguta (multiplication rate of 8.0) and A. polygama (6.8) developed faster at the micropropagation stage compared to A. kolomikta (4.9). The studied Actinidia representatives were cultured most effectively on Quoirin and Lepoivre media supplemented with 0.5 mg L^-1 meta-topolin, compared to the media containing 0.5 mg L^-1 6-Benzylaminopurine and 0.5 mg L^-1 2-isopentenyladenine. The use of meta-topolin in the medium contributed to the increase in various morphometric traits, such as the height of microshoots (up to 28% depending on the species), their number (up to 52%), and their multiplication rate (up to 42%). We also recorded a high morphogenic capacity of the investigated species.

Index terms: A. arguta; A. kolomikta; A. polygama; cytokinin; regeneration.