Effect of plant growth regulators on biochemical compounds of tangerine (Citrus unshiu Marc.)

We investigated the effect on tangerine of new generation plant growth regulators. The use of drugs in the period of fruit ripening has led to increased 2.0 – 3.7 times abscisic acid (AA) and 1.9 – 4.7% of Indole-acetic acid (IAA) acid in the leaves. Studies have shown that Indole-acetic acid and abscisic acid beginning of a sharp accumulation of their hormones coincides with action of stress factors and growth dormancy period. The use of the regulators had an impact not only on their content in leaves but also on fruit quality. For example, treatment Indole-acetic acid and Obstaktin led to an increase in the fruit of vitamin C. After treatments with plant growth regulators has been a significant decline in the total number of organic acids (up to 2.35% at the option of Melaphen and to 2.50% at Obstaktin, LSD (p ≤0.05) = 0.06). By reducing the content in the fruits of organic acids to all variants increased the sugar-acid index. After each spraying tangerine on the treatment options plant growth regulators has been a significant increase the dry matter. Thus, the positive effect of plant growth regulators on all the quality characteristics of tangerine was shown. In the summer period, the treatment by regulators may have a protective effect, increases the content in plants the content of Indole-acetic acid. The plant growth regulators of new generation have a positive effect on quality of dwarf tangerine. Given that the plants of tangerine in the subtropical zone of Russia each summer have to drought and are losing not only in yield, fruit quality too, new regulators may exert a protective effect, because increases the content in plants is Indole-acetic acid, which activates gene expression of drought resistance.