Physiological effect of citrate chelate nanoparticles on plants of wheat

Abstract

Aim. Complex study on the physiological effect of citrate chelate nanoparticles of silver and copper on spring wheat plants under presowing soaking of seeds and foliar treatment of plants. Methods. Physiological, biochemical, bio- physical, microbiological, statistical. Results. The data on the physiological effect of the presowing soaking of seeds in the solutions of citrate chelate nanoparticles of silver and copper on growth processes and photochemical activity of leaves in laboratory conditions have been studied, analyzed, and summarized along with the effect of foliar treatment of spring wheat plants using the solutions of nanoparticles, and simulated phytoplasma (Acholeplasma laidlawii var. granulum st. 118) on the elements of the performance of spring wheat plants in fi eld conditions. It was demonstrated that there was a considerable stimulating effect of presowing soaking of wheat seeds in 0.5 % and 1 % solutions of nanocomposites on the growth of leaves and mass accumulation of 6–7-day old sprouts. A considerable increase in the photochemical activity of the leaves of 7-day-old sprouts was found after presowing soaking in 0.5 % and 1 % solu- tions of nanocomposites which is in good agreement with the activation of growth processes. The negative effect of phytopathogens on the elements of grain productivity, fullness of grain in particular, was reduced in fi led conditions when wheat plants were infected and then treated with nanocomposites, though there was a weak phytotoxic effect of foliar treatment of intact plants with 1 % solution. Conclusions. A considerable stimulating physiological effect on the growth of leaves and mass accumulation of 6–7-day-old sprouts was established after the presowing soaking of spring wheat plants in 1 % and 0.5 % solutions of citrate chelate nanoparticles of silver and copper. The increase in photochemical activity was noted in the leaves of 7-day-old wheat plants in these conditions, namely, the increase in photochemistry effi ciency PSII, considerable decrease in stationary fl uorescence and considerable – almost trip- le – increase in the value of induction coeffi cient Ki (correlating with the activity of ribulose biphosphate carboxylase (RuBPco)) which testifi es to the increase in the intensity of photosynthetic processes in the leaf apparatus of juvenile wheat plants. The fi eld experiment established that infecting wheat plants with phytoplasma (A. laidlawii) resulted in the reduction of the grain productivity indices: the weight of 1,000 grains and grain productivity in g/plant – by 14.6 and 35.5 % respectively, whereas treating with 1 % solution of silver and copper nanocomposites inhibited this process to some extent, promoting the increase in these parameters almost to the control level. The treatment of infected plants with nanoparticles led to a notable increase in the percentage of full grains. There was a weak phytotoxic effect after foliar treatment of intact wheat plants using nanocomposite solution.