The economical efficiency of classic and no-tillage system at genetical modified soybean in conditions of Romania.

The technology of maize without plough land possible to apply in USA and other countries with advanced agriculture, only by atrazine and simazine herbicides synthesis by J. Geigy Company from Switzerland Phillips and Young (1973) said in their book that in USA is practicing no-tillage system on millions acres. After recently dates published by Derpsh (2001) in USA no-tillage is practice on 21,120,000 ha, in Brazil on 14,330,000 ha, in Argentina 10,500,000 ha etc. The chernozem soil in Romania is very properly for no-tillage system. First experiments with no-tillage system have been since 1965 at maize, and at soybean since 2002 until 2005, obtaining remarkable results concerning maize and soybean yields. At genetically modified soybean crop the economic efficiency is very big because fuel consumption was 75 l/ha at classic system and only 21 l/ha at no-tillage system. The expenses with mechanical working were 217 Euro/ha at classic system and only 45 Euro/ha at no-tillage system.

The residual effect of imazethapyr applied in soybean to barley and winter wheat in Romania.

Many experiments have been made in Romania in the period 1965-2000 regarding the remnant effect of atrazine herbicide on different plants: barley, wheat, peas, soybean, beans, potatoes, sugar beet, flax, hemp, etc. The remnant effect of imazethapyr herbicide is similar to the effect of atrazine. Selectivity in soybean is attributed to a rapid detoxication via hydroxylation and glycosylation in the course of the days 1-6. The persistence of the imazethapyr herbicide in the soil is very long. By the dates of American Cyanamid Company, soybean, barley and wheat treated with imazethapyr can be cultivated only after 2-3 years, and sugar beet only after 4 years. Based on experiments made on chernozem soils in Romania, the conclusion that after the treatment of the soybean with imazethapyr in doses of 100-150 g/ha barley and winter wheat can be cultivated already in that autumn after the soybean harvesting, has been drawn. The results at barley and winter wheat shall be presented in this study.

The chemical control of Shorgum halepense (Johnson grass) in soybean culture in the Danube meadow.

Soybean cultures, especially those from the Danube Meadow, are very strongly infested with Johnson grass, which causes big damages, by the reduction of production with 40-85%, depending on the infestation degree. Before the synthesis of special herbicides for Johnson grass control, this species was controlled by practicing deep tilling, repeated operations with the disk, and, after the sprouting of soy plants, by mechanical and manual hoeings. In the Danube Waterside, the lack of labour force for the manual hoeing is very sharp. For this reason, it was generalized the enlarged use of herbicides for annual weed control (monocotyledonous and dicotyledonous), including Johnson grass. For the control of Johnson grass species, in the conditions of the Danube Meadow, the best results were obtained with the herbicides Fusilade Super, Targa Super, Agil and Select, and for the control of annual dicotyledonous species, with the herbicide Pivot 100LC.

The chemical weed control of maize culture in the Danube meadow.

In the world, maize covers about 150 million hectares, following close to rice and wheat. (Balteanu 2000) In Romania, maize culture covers an area of more than 3,500,000 hectares from the overall arable soil, being cultivated in all Romanian districts. Chemical weed control took the greatest extension in the world, at the same time with the synthesis of Atrazine, in 1956, in the laboratories of J.R. Geigy Company, as a super-selective herbicide for the maize culture. This is why many researchers from all continents studied weed control of maize culture, using Atrazine together with other 50 herbicides synthesized until 2004. In the embanked meadow of the Danube, from the 500,000 hectares of arable soil, the maize covers the greatest area. For this reasons, the chemical weed control was granted a great attention by using different herbicides based on Atrazine, Alachlor, Acetochlor, Butilat, Pendimethalin, Dicamba, 2,4-D. At the same time, in the experiments from the Danube Meadow, the authors also studied the efficiency of some combined herbicides: Butizin, Magnific, Guardian Extra is Tazastomp.

The chemical control of Sorghum halepense species in sunflower culture, in the Danube meadow.

In the latest years, sunflower was cultivated in Romania on an area of 800-900 thousand hectares. On 100 or 150 thousand hectares we find it cultivated also in agricultural farms in the Danube Meadow, because sunflower has favorable conditions on these soils, productions exceeding sometimes over 4000 kg/ha, of course, in irrigation conditions. In the Danube Meadow, the first experiments on Sorghum halepense (Johnson grass) species were performed by Fane Popa and colleagues (1986), at the agricultural station of Braila, using the herbicide Fusilade. In our experiments, the herbicide fusillade was compared with different more recently synthesized herbicides: Super, Pantera, Agil, Select, with the specific purpose of identifying the most favorable dose.