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.

The composition and content of phenolic compounds in tea, grown in humid subtropics of Russia

The article presents the results of studies on the dynamics, qualitative and quantitative composition of phenolic compounds of tea raw materials and tea of new forms of selection of the Institute. The regularity in their synthesis by months is determined, which affects the quality indicators of the end product and necessitates blending to the repaired tea. The accumulation of tannins in tea raw materials depends on hydrothermal conditions, in particular, the amount of precipitation. The content of tannin increases from May to June, then there is some decline in their content, due to hydrothermal stress, slowing the synthesis of tannins in the tea leaf. The content of the water-soluble fraction gradually increases from May to July, and then there is a slight decline. It is shown that the accumulation of phenolic compounds in tea raw materials varies during the collection season. The contents of theaflavins increased from the beginning of the collecting sheet to its completion. The content of thearubigins showed peaks: the lowest rate in June, the highest in August. It was revealed that a sharp drop in the synthesis of thearubigins in June is associated with the onset of the summer dormancy of growth and synthetic processes. The synthesis of both indicators depends on meteorological conditions. The comparative analysis of the samples of tea raw materials collected from experimental plants is carried out. It is shown that the content of tannin and extractive substances in the raw materials of the studied varieties and mutant forms is high. In terms of the ratio of theaflavins and thearubigins, tea made from experienced raw materials meets international requirements. Determination of the qualitative composition of the catechin group of green tea, produced from raw materials of new forms, showed a high level of accumulation of the main groups of catechins.

The effect of foliar feeding on physiological condition of apple trees and chemical content of fruits

Chemical content of leaves and fruits of the low growing apple trees on the rootstocks SК4 and М9 in the result of application of foliar feeding with water solutions of various mineral fertilizers was studied. Special ballastless multi-nutrient fertilizers in solid and liquid forms containing a wide range of chelated microelements were used. The effect of foliar feeding on the content in plants and fruits of macro- and microelements at the fruit maturity stage was estimated with the help of the method of leaf analysis. Significant stable increase of the content of nitrogen and potassium was observed in the leaves of apple trees on the rootstocks SК4 and М9. The content of potassium and calcium in apples became higher. With the help of statistical analysis it is shown that there exists close correlation between the content of elements in leaves and fruits: (N) r = 0.79; (K) r = 0.77; (Ca) r = 0.94; (Cu) r = 0.75; (Mn) r = 0.89; (Zn) r = 0.75; (B) r = 0.70. In the result of our physiological and biochemical tests positive effect of mineral feeding on the functional condition of apple trees during summer season when being subjected to intensive hydrothermal stress factors was established. The foliar feeding effect appeared as changing of the ratio of water fractions in the apple tree leaves at the background of increasing atmospheric drought, which in some years in July and August reached the criteria of "hazardous weather". Sufficient level of water content in the cells of apple trees on the rootstocks SК4 and М9 in case of foliar application of fertilizers was ensured as a result of bound water increasing. Statistic analysis of the experimental data showed significant changes in the ratio of bound and free water fractions. In August, in the environment of strong impact of negative abiotic factors, at higher level of water content in the tissues it was found that the content of pigments in leaves was much higher than in the reference version. The functional changes confirm that application of mineral nutrients contributes to activation of the adaptation mechanism. When foliar feeding is used the content of biologically active substances in apples is the highest: content of vitamin C increases by 13.6 - 15.2%, vitamin Р - by 8.7 - 24.6%.