Micropropagation of two varieties of strawberry (Fragaria ananassa Duch.) in different culture media

Mamani-Sánchez Beatriz; Murillo-García Rafael Adolfo

Abstract

Strawberries spread asexually, causing a decrease in yield, loss of fruit quality and degeneration due to the accumulation of diseases. An alternative to obtain high-quality plant material for plant protection is through micropropagation. The objective of the present work was to determine a micropropagation protocol of two strawberry varieties (Big Bear and Sweet Charlie). Two types of explants (stolon buds and crown) were used and they were subjected to different disinfection treatments, varying NaClO concentrations and immersion times. In the multiplication and rooting phases in vitro, the two varieties were seeded with MS medium with 0.5, 1 and 1.5 mg L^-1 of BAP (0.5 mg L^-1 AIB was added to the culture media) and at 25, 50 and 75% DM respectively. The growth room registered an average temperature of 24ºC with a photoperiod of 16/8 hours of light / dark and a light intensity of 1800 lux. Disinfection was adequate for crown explants with 2% NaClO for 25 minutes and for stolons with 0.8% NaClO for 13 minutes. The latter regenerated in less time (13 days) compared to those of the crown that required 28 days. In the multiplication, in the first subculture both varieties managed to obtain more shoots in the medium MS+0.5 mg L^-1 of BAP+0.5 mg L^-1 of AIB. However, in the second and third subcultures Sweet Charlie generated a greater number of outbreaks in the MS medium+1 mg L^-1 of BAP+0.5 mg L^-1 of AIB and Big Bear in the medium MS+0.5 mg L^-1 of BAP+0.5 mg L^-1 of AIB. For rooting, the media at 50 and 75% DM concentration were the most adequate in both varieties, on the contrary, at 25% DM concentration, they showed symptoms of phosphorus and nitrogen deficiency.