Nanoparticles of biogenic ferrihydrite in the technology of green cuttings of steppe cherry

Steppe cherry is the most common stone fruit crop in the gardens of the Krasnoyarsk Region. The demand for cultivar seedlings increases annually. The main method of industrial reproduction of planting material is green cuttings. Synthetic stimulants of root formation of auxin nature are used in the propagation technology. To improve the rooting of cuttings, it is proposed to use indole-3-acetic acid (IAA) with the addition of biogenic ferrihydrite nanoparticles (Feh). The purpose of the research is to study the effect of biogenic ferrihydrite nanoparticles on rhizo- and organogenesis of green cuttings of steppe cherry induced by the phytohormone IAA. 1 mg of nanoparticles was added to 1 l of IAA solution. Green cuttings of the Subbotinskaya variety, harvested in the first ten-day period of July, were soaked in solutions of root formation stimulators for 12 hours. Experimental variants: 1) IAA, control; 2) IAA + nanoparticles of biogenic ferrihydrite (IAA + Feh); 3) IAA + nanoparticles of biogenic ferrihydrite doped with aluminum (IAA + Feh_Al); 4) IAA + nanoparticles of biogenic ferrihydrite doped with cobalt (IAA + Feh_Со); 5) IAA + nanoparticles of biogenic ferrihydrite doped with silicon (IAA + Feh_Si). After treatment, the cuttings were planted in a greenhouse with fine-drip irrigation in 3-fold repetition, 30 cuttings per plot. The substrate was peat + sand in a volume ratio of 1:1. The cuttings were placed 7 ? 7 cm. The effect on stem cuttings of the rhizogenesis-initiating compositions IAA + Feh, IAA + Feh_Со, IAA + Feh_Si contributed to a statistically significant increase in rooting by 18.9: 22.2 and 24.8%, respectively, compared to the control, as well as to better development of the root system of rooted cuttings. All modifications of rooting stimulants with the addition of nanoparticles had a reliable effect on increasing the total length of shoots and the rooting zone on the cutting. The composition IAA + Feh_Al is inferior to other experimental stimulants in terms of the effectiveness of the effect on the morphometric parameters of rooted cuttings.