The aim of our research was to study the peculiarities of alfalfa seed varieties formation with the purpose, first of oll removal of batteries weeds from the soil in varying degrees agrophytocenoses weed-infested.
The processes of plant growth and development in agrophytocenoses alfalfa seeds studied at the Mykolayiw Institute of APV for three years. The main control in the experiment were Synska crop varieties (without application of herbicides and hand weeding grass).
The results of research. I is established that the spring sowing lucerne herbage under the open land very clogged. At the control sites (no herbicides) the number of weeds during their mass occurrence ranged between 418-437 individuals/m2 (high degree of contamination) and crude and air-dry weight – 162,0-168,0 and 28,8-29,3 g/m2, depending on the variety. In areas with the introduction of herbicide (with ground – Eptam 6E normally 4,5 l/ha after germination – Bazahran, 48% – 2 l/ha) during the mass appearance of weed noted weak degree of contamination (8-9 pcs./m2). Crude and air-dry weight of these were depending on the variety 18-19 and 2,2-2,7 g/m2, respectively.
During crooked ripening seeds in areas with the settings of herbicide the weed number decreased to 94,3 (sort Synska) 88,9 (sort Darkie), 91,2% (sort Torch) compared to untreated crops. Chemical weeding alfalfa helped to reduce air-dry biomass of weeds, which was 5,6; 5,8; 5,9% of the value accumulated in controls (454,0; 468,0; 452,0 g/m2), respectively, for the aforementioned grades. Weeds absorb from the soil of the high degree of contamination 37,1-38,4 kg/ha nitrogen 6,3-6,6 kg/ha – phosphorus 86,3-89,4 kg/ha of potassium depending on their sorts. This related to an average of 4,2 GJ/ha of non-renewable energy. Due sowing and post settings of herbicides the absorption from the soil decreases and is only 0,2 GJ/ha, ie 21 times less than in control.
Thus, the controlling unwanted vegetation in crops of alfalfa seed designation in time allows more efficient use of fertilizer and does not degrade the indexes of the natural fertility of the soil.
Key words: alfalfa seed, weeds, nutrients, exchange energy, productivity of crop sowing.