Light spectral composition influence on strawberry microclonal propagation (Fragaria x Ananassa duch.) in vitro

The purpose of research is to study the effect of the spectral composition of light on the proliferation and rooting of shoots during microclonal propagation of the garden strawberry of a neutral day, the Cabrillo variety. The study was carried out in 2021-2022 in the Laboratory of Agricultural Biotechnology of the Federal State Budgetary Scientific Institution “Federal Scientific Center of Agricultural Biotechnology of the Far East named after A.K. Chaika”. The object of the study is the microshoots of garden strawberry of the remontant variety of neutral light day Cabrillo (Cabrillo) in in vitro culture under different light spectrum. The following lighting options were used for strawberry micropropagation: 1 - phyto-rack with white LED lamps (SPB-T5-eco) in combination with LED phyto-lamps (SPB-T8-Fito); 2 - phytoshelf of LLC ELSIS BelGU with LED lighting of the X-bright Fito series; 3 - phytoshelving of LLC AVTech with white fluorescent lamps (TL-D 36W / 33-640, Phillips) in combination with phytolamps (L 36W/77 Fluora, Osram). Illumination was measured with a TKA Luxmeter (Russia), and the irradiance level was measured with a TKA-Spectrum (FAR) spectrophotometer (Russia). The experiment took into account the number of shoots formed, the number of leaves, the number of roots; the height of the plants, the length of the roots were measured under different lighting conditions. Illumination with LED lamps with predominance of red light in the spectrum (option 2) ensured the regeneration of the largest number of garden strawberry shoots; the multiplication factor was 8.0 per explant. For the rooting stage, the best lighting option was also the 2nd option with LED lamps, in which strawberry plants of maximum height (4.5 cm) and a large number of roots (8.5 pieces) were formed. The largest number of roots (8.6 pcs.) was formed in plants under LED lighting with predominance of the blue spectrum (1st variant). In microclonal propagation of remontant garden strawberries of a neutral day, variety Cabrillo, it is more efficient to use LED irradiators for lighting than fluorescent ones.