RESEARCH ON CHOOSING THE OPTIMAL DOSAGE OF HERBICIDES CEREDIN SUPER (300 g/l 2.4-D + 100 g/l Dicamba) AND ASTRAL 40 SC (Nicosulfuron 40 g/l) APPLIED TO CONTROL WEEDS IN MAIZE CROP

Studies have been conducted for two consecutive years, 2013 and 2014 respectively, in the climatic conditions of Braila Plain. The experience was monofactorial, including six variants in three repetitions, placed on the Latin rectangle method, experimental plot measuring 12.6 square meters and a total area measuring 300sqm. Graduation experimental factor were: V1 (Ceredin Super 0.8 l/ha + Astral 40 SC 0.8 l/ha); V2 (Ceredin Super 1 l/ha + Astral 40 SC 1 l/ha); V3 (Ceredin Super 1.2 l/ha + Astral 40 SC 1.2 l/ha); V4 (Ceredin Super 1.5 l/ha + Astral 40 SC 1.5 l/ha); V5 (untreated) and V6 (hand weeding). Hybrid corn used was PR39D34. Particular sensitivity to weed corn manifested predominantly untreated variant, noticing increasing weed from 89 plants/sqm in 2013 and 92 plants/sqm in 2014, in phase 4-6 leaves of corn, 165 plants/2013 sqm and 169 plants/sqm in 2014, at the end of the vegetation period of maize. Compared to hand weeding were revealed statistically significant two variants, namely V3 (Ceredin Super 1.2 l/ha + Astral 40 SC 1.2 l/ha) and V2 (Ceredin Super 1 l/ha + Astral 40 About 1 l/ha), with an average of weed 81 and 77% in 2013 and 80 and 74% in 2014 compared to control 88% manual weeding. Also, we determined the elements of productivity and yield obtained from each experimental variant compared with untreated variant, and was established correlations between doses of fertilizer and values of productivity elements.