Structural and functional changes in the leaves of black currant seedlings using nanoparticle solutions

Abstract

When propagating black currant by lignified cuttings in order to obtain high-quality planting material in one growing season in the conditions of the forest-steppe zone of the Krasnoyarsk Territory, solutions of biogenic ferrihydrite nanoparticles were used in three modifications with the addition of traditional growth hormone (indolyl-3-acetic acid): control (soaking cuttings in water); treatment of cuttings with indolyl-3-acetic acid (IAA); IAA+ferrihydrite (IAA+Feh); IAA+Co-doped ferrihydrite (IAA+Feh_Co); IAA+ferrihydrite doped with Mn (IAA+Feh_Mn). The object of the study is blackcurrant plants of the Selechenskaya variety. The area of the assimilation surface and the pigment composition of the leaves were assessed in dynamics. Before planting, black currant cuttings were soaked in nanoparticle solutions (exposure 12 h), then, during the growing season, four times (with an interval of 14 days) exogenous treatment of the leaf surface of rooted cuttings with the same solutions of nanoparticles, but without the addition of IAA, was carried out. The results of studying the concentration of pigments in leaves and biometric observations in the dynamics of the growing seasons of 2021 and 2022 are presented. It has been established that the maximum concentration of chlorophyll a and b, carotenoids in black currant leaves by the end of the growing season was affected by the use of solutions of ferrihydrite nanoparticles doped with cobalt and manganese with the addition of IAA. Thus, the concentration of chlorophyll a, b increased by 1.3 and 1.6 times, respectively, in the variant with cobalt-doped ferrihydrite nanoparticles compared to the control. In our studies, the values of the assimilation surface of leaves depended on the climatic parameters of the year of study and on the content of photosynthetic pigments in blackcurrant leaves. Between the area of the leaf blade and the concentration of chlorophyll a, a direct relationship was noted (r=0,87), a close relationship: in 2021 between the area of the leaf blade of black currant and the amount of precipitation (r=0,83-0.94), in 2022 between the area of blackcurrant leaf blade and air temperature (r=0,85-0,93). It has been established that the best conditions for the formation of the assimilation surface of blackcurrant leaves of the Selechenskaya variety are created by soaking cuttings and foliar treatment of vegetative plants with ferrihydrite nanoparticles doped with cobalt and manganese.