Properties of crezacin as a growth stimulant of vegetable amaranth (Amaranthus L.)

Abstract

Crezacin, tris(2-oxyethyl)ammonium ortho-cresoxy acetate-based adaptogen of humans and animals, is applied in Russia as a stimulant of growth and productivity of crops (wheat, oats, spinach, potatoes, etc.). In other countries, crezacin is not used for these purposes. There is no information about its use in the cultivation of food amaranth (Amaranthus L.), a source of high-quality protein and other useful substances. In this paper, we first report data on the effect of pre-sowing treatment with crezacin on seed germination, development and biometric parameters of amaranth plants during ontogenesis, and on their productivity and nutritive value. Our findings indicate the ability of crezacin to increase nitrate reductase activity, to influence the nitrite nitrogen content in the early stages of vegetation, to increase the electron transport rate ATP synthesis. The aim of the work was to assess the effect of different crezacin concentrations on seed germination, seedling quality, growth parameters, and activity of photosynthesis and nitrogen assimilation apparatus. Seeds of Amaranthus caudatus L. (sample K173) and Amaranthus cruenthus L. (sample K185) were soaked for 1 day in crezacin solutions (test) or in distilled water (control), and used in the experiments after airdryingat room temperature. In experiment 1, 10-10 π 10-5 M aqueous crezacin was applied to seeds then allowed for germination on wet filter paper in Petri dishes for 72 h at 24 °C. The proportion of germinated seeds was calculated. In experiment 2, we studied the effect of crezacin on the growth and physiological and biochemical parameters of plants. Seeds were treated with 10-7 M crezacin, germinated, and calibrated seedlings were transplanted into sand- filled container. Biometric parameters were measured every 15 days until harvest (120 days), productivity was estimated by the green mass increase. Chlorophyll concentration was assessed in the leaves of 45-day-old plants. The photochemical activity of isolated chloroplasts was evaluated by the rate of electron transport and photophosphorylation. From day 15 to day 45, the activity of nitrate reductase, the concentrations of NNO2 and total protein were measured in the leaves. The net photosynthesis (NP) for the period from day 45 to day 60 was calculated by A.A. Nichiporovich's method. Experiment 1 revealed a change in seed germination depending on the concentration of the preparation in both studied samples. A 10-8 concentration increased seed germination capacity by 10 % compared to control (P = 0.95), 10-7 M had maximum stimulating effect (by 25 %), and at 10-5 M the germination rate decreased by 22 %. Other concentrations had no significant effect. In experiment 2, in both varieties during latent growth stage the seedlings from the treated seeds were twice as high as the control, and the length of the main root was 1.6 times as much as in control. During later stages, the green mass of plants in the experiment exceeded the control 1.3-2.0-fold depending on the phase of ontogenesis. The treatments did not affect the height of plants. The NF value in leaves after treatment exceeded the control by 26 % (P = 0.95). At the same time, the chlorophyll content in the leaves did not change, and the electron transport rate in chloroplasts increased by more than 30 % while photophosphorylation by 60 %. The nitrate reductase activity in leaves on day 45 increased by almost 60 %, the total protein level by 20 %, and nitrite nitrogen amount by 16 % (P = 0.95). These findings indicate the stimulating effect of crezacin on amaranth seeds, plant growth, photosynthesis and protein synthesis, which leads to an increase in the productivity and nutritional value of plants.