Factors affecting soybean productivity and seed quality are weedery (soybean has low competitiveness to weeds), as well as defeat of plants by numerous diseases of different etiology, arisen from the soybean crops area expansion in different regions of Ukraine. As modern soybean technologies need a reliable, environmentally safe and economically viable systems to protect crops from weeds and diseases, it is important to select the herbicides (tank mixes) and highly efficient fungicides for double using to soybean crops in order to protect plants for a long vegetational season.

The paper presents the results of a three-year (during 2012-2014) experimental research on the effect of the herbicides and fungicides usage in order to protect soybean crops from weeds and affection for a long growing season, the formation of photosynthetic and grain productivity of soybean, and quality indicators of grain as well.

The study was carried out on dark grey degraded (podzolized) soil with the following agrochemical indices: humus at a depth of 0-20 cm by Turin is 2,0-2,11 %; providing alkali-hydrolyzed nitrogen is low; a degree of mobile forms of phosphorus and potassium is high.

The reaction of soil solution is nearly neutral – 5,9.

It is a three-time repeated experiment. Randomization method was used for option placement. It was used Ustya soybean variety (originator – NSC "Institute of Agriculture NAAS"). Soybean cultivation technology was common for the soil-climatic zone.

The results of a three-year research show that yield and grain quality indicators of Ustya soybean largely depend on the weed and disease protection system. Thus, in the first variant with using the soil herbicide Harnesses (2,5 l/ha) the soybean productivity was the lowest and amounted to 2,21 t/ha.

In the second variant Harnesses (2,5 l/ha) + Bazahran (2,0 l/ha) + Harmony (7 g/ha) were used in a three-leaf phase. It provided grain yield at the level of 2,62 t/ha, which is 0,41 t/ha or 18,6 % higher compared to the first variant with soil herbicide Harnesses (2,5 l/ha).

The application of herbicides Bazahran (2,0 l/ha) + Harmony (7 g/ha) provided soybean yield at the level of 2,32 t/ha, which is 0,11 t/ha or 4,9 % higher compared with the control variant. It is necessary to note that at this variant soybean plantings much suffer from grass weeds.

The application of Pulsar (0,75 l/ha) + Bazahran (2,5 l/ha) in a three-leaf phase provided the highest yield (2,74 t/ha). It is 0,53 t/ha or 24,0 % higher to control variant.

A direct relationship (r = 0,67) was detected as a result of correlation and regression analysis between yield and herbicides.

By using fungicides the lowest yield (2,20 t/ha) was observed at variant with Impact K (0,8 l/ha) + Coronet (0,6 l/ha).

The highest soybean yield (2,70 t/ha) was observed at variant with Coronet (0,6 l/ha) + Abakus (1,5 l/ha). It is 0,50 t/ha or 22,7 % higher compared with the first variant.

Results of regression-correlation analysis showed that there is direct strong relationship (r = 0,99) between yield and using of fungicides.

It was found that the highest protein content (34,5 %) was formed at variant with herbicides Pulsar (0,75 l/ha) + Bazahran (2,5 l/ha).

The highest oil content (20,5 %) was observed at variant with Harnesses (2,5 l/ha). It was checked strong inverse relationship (r = -0,71) between protein and oil.

With the use of fungicides the highest protein content (37,8 %) was noted at variant with Coronet (0,6 l/ha) + Abakus (1,5 l/ha). That is 5,3 % higher compared to the first variant with Impact K (0,8 l/ha) + Coronet (0,6 l/ha).

Oil content in this variant was 19,4 %. It was found a strong inverse relationship (r = -0,99) as a result of correlation analysis between oil and protein.

In the Western Forest-steppe the highest grain yield of Ustya soybean (2,74 t/ha) is formed by applying in a three-leaf phase Pulsar (0,75 l/ha) + Bazahran (2,5 l/ha). The highest protein content (34,5 %) is set at this variant.

Double serial using of fungicides Coronet (0,6 l/ha) + Abakus (1,5 l/ha) in the early stages of budding and flowering completion provided obtaining the highest yield (2,70 t/ha) and the highest protein content (37,8 %). It was observed inverse correlation dependence between protein and oil.

Key words: productivity, soybean, variety, protein, oil, herbicides, fungicides.