The Effects of Some Agricultural Measures on Plum Behaviour under Different Pedo-Climatic Conditions from Romania

The greatest part of Romanian plum orchards is located on clayed - iluvial soils with a high clay content, low permeability and a water - air regime less favourable, showing frequently on excess deficit of moisture under our climatic conditions. To establish the best technological measures for improving such conditions, some investigations were carried out for a long period of time within the Research Institute for Fruit Growing Pitesti. The results obtained showed that on the albic pseudogleyed vertic luvosol, versus the ploughing at 23 cm, deep ploughing at 55 cm determined a significant increase by 43% of TCSA and by 107% of fruit yield. In exchange, on the typical planosol, versus the ploughing at 23 cm, deep ploughing at 55 cm determined an increase only by 20% of fruit yield per cm(2) of TCSA and a decreasing by 13% of TCSA. The clean cultivation versus the grass strips system between tree rows, determined a significant increase of tree growth and fruiting. However, because of the positive effects of grass strips system on physical and chemical soil properties, this system will be used in all zones where there is a good water supply for an optimum tree growth and fruiting. Application of the 20 kg/tree manure at planting, versus the application of 40-80 t/ha manure on the entire area before soil preparation, determined a better tree grows in fruiting.