Filipova L. Efficiency of the natural and synthesized regulators of growth by useing under seed potato.

The dissertation deals with results of researches of efficiency some new regula-tors of growth on Zov, Svitanok kievskiy and Borodyanska rogeva potatoes. The significant inhibiting effect at application of a regulator of growth DG - 613 in concentration of 5,0 and 10,0 % was established before storing. The greatest stimulating effect has been provided with preplanting treatment of seed potato with a mix of preparations DGA-82 (0,5 %) and EPS (5,0 %). Prepara-tions promoted reduction of the photosynthetic area of leaves on 3,9 th.m2/h and quantity of stalks on 1,1 piece on a bush. It has provided formation in a jack much more of tubers (on 0,8 pieces) and big on weight (on 11,7 g.). Thus the productiv-ity increased on the average for three years on 53 c/h. Increasing an amount of stalks and the photosynthetic area of leaves also promoted the preplanting treat-ment of seed potato with preparations DGA-82 in concentration 2% and DSB - 10%. The increase of productivity has made accordingly 36 c/h and 27 c/h. Significant stimulating effect has been marked at preplanting treatment of seed potato with PABK (0,05%). The amount of stalks has been increased on 0,5-0,8 pieces by a bush, the leavs' area - on 4,3-4,5 th.m2/h, productivity - on 49-53 c/h. Highly effective there was an application of EPS in concentration 5,0% on both grades - tubers' productivity increased on 21-29 c/h. Together with a high level of productivity the preparations did not make worse the quality of tubers, and in some cases, on the contrary, promoted its increasing. Application of these preparations is also characterized by high economic and power efficiency.