Growth stimulating activity of avermectin-containing preparations on tomato lines in vitro

Aim. Obtaining of the tomato lines of cvs. Money Maker and Lahidny in the presence of polyfunctional preparations Avercom and Avercom Nova and cytological analysis of their influence on tomato root cells. Methods. Cotyledons of 10–11-day-old tomato seedlings were cultivated on MST medium for 1–3 months in the presence of 1 mg/l zeatin, 1 mg/l indole-acetic acid and 25 µl/l of Avercom or Avercom Nova. Then, regenerated lines were grown on MST medium supplemented with biopreparations for 1 month. The roots of tomato plants were fixed in the solution of ethanol and glacial acetic acid (3:1), stained in 1 % acetoorseine solution and investigated at x600 magnification. Results. In this work, the tomato lines were obtained and grown in the presence of biopreparations Avercom or Avercom Nova. It was shown that mitotic index (MI) in the root meristematic cells of the plants grown in the presence of biopreparations was at 0.76–1.23 %, and it was higher than in the control plants (0.65–0.9 %). Moreover, the thickened cell walls of root cells of plants grown in the presence of biopreparations was detected compared to control plants. Conclusions. Tomato plants grown in the presence of biopreparations Avercom or  Avercom Nova are characterized not only by the increased MI of  meristematic cells but also by the thickened cell walls of root cells which indicate the growth stimulating effects of biopreparations and their capacity to enhance the resistance of plants to stressful factors.