The purpose of this study consists in establish the optimal variant of soil conservation that ensure favorable conditions for plant growth and development, in pedoclimatic conditions of Moldavian plain. The experience was carried out in the eastern part of Romania in experimental field of Didactical Station of USAMV Ia ș i, Ezăreni Farm and the main objective is to assess the degree of compaction and the productivity of soybean crop under the influence of conventional system: ploughed at 30 cm (V 1 ) and unconventional systems – paraplow (V 2 ) chisel (V 3 ) and disk harrow variant on a cambic chernozem with a clay loamy texture, 6.6 – 6.9 pH units, 33 – 34 % clay content middle provided in N and P 2 O 5 and agreebly in K 2 O. Studies of many researches has concluded that some areas such tillage systems are incomplete discussed and showed a new approach and a pronounced increase of research in the development of systems for their conservation. The results obtained from the research can be generalized in terms of production in Moldavian plain and in other areas with similar climatic conditions, farmers can apply these treatments to improve and maintain the physical condition of soil. Indicators of state of compaction increased from sowing to harvesting and with the depth in all experimental variants. The values of bulk density at the end of vegetation period change under the influence of tillage systems and soil depth. The values on 0 – 10 cm depth increased with 0.07 g/cm 3 compared with 10 – 20 and 20 – 30 cm , where the mean values of bulk density were 0.05 g/cm 3 and respectively 0.03 g/cm 3 . The degree of compaction at sowing showed reduced values, then increased with depth, reaching to harvest at a slightly compacted soil. The values of penetration resistance showed a clear distinction through the soil profile, with maximum values at disk harrow (0.84 – 2.34 MPa), minimum values in ploughed at 30 cm variant (0.69 – 2.27 MPa) and intermediate values at chisel variant (0.65 – 2.29 MPa) and paraplow variant (0.67 to 2.30 MPa). The crop yield performed by unconventional tillage systems (2954 - 3134 kg / ha) have values of those obtained by plough variant (3339 kg/ha) except disk harrow variant (2656. 6 kg / ha).

physical properties; tillage systems; bulk density; resistance to penetration; soybean

Presentation: oral