Fruit growing
and viticulture of South Russia

Annotation

Under the conditions of the Tambov and the Lipetsk areas the influence of fertigation on apple-tree productivity and distribution of available phosphorus in the soil are investigated. The features of migration of available phosphorus in the apple-tree plantings of different varieties on soil layers of 0-20, 21-40, 41-60 and 61-80 cm are established: directly under a dropper, between the droppers in a row and at distance of 30 and 60 cm towards the center of a row-spacing. It is shown that a drop irrigation affects on the distribution of available phosphorus on the soil layers. Phosphorus is washed away from the upper horizons, especially under a dropper, and it distributes on all depth of root layer. It makes phosphorus more available for apple-tree plants. It is established that the fertigation provided the higher level of the content of available phosphorus in the soil, than in control, and also other distribution of it on layers of soil that promoted the increase of plants productivity. Under the conditions of fertigation the horizontal migration of phosphorus on distance of 30-60 cm as in the direction of a row, and so in direction of row-spacings, and the descending migration of phosphorus in the layers of 41-60 and 61-80 cm is noted. The content of phosphorus in these soil layers was much higher, than in the control. It is noted that in the plantings with a high density of landing the regime of plants nutrition is optimized and so the productivity of apple trees increases. In our experiences the increasing productivity at the intensive apple-tree of Imrus PB-9 was about 60 % and - 77-98% for Lobo variety, and 24-46% for Spartan apple-tree.

Annotation

Apple varieties have different response to fertilization and changes of root nutrition conditions. For three years, we studied the effect of fertigation on the content of nutrients in the leaves and the yield capacity in apple cultivars: Lobo and Spartan, grafted on rootstock 62-396. Planting scheme is 4 x 1 m, trees were cultivated on meadow-chernozem and dark gray forest soils. The experiment on meadow-chernozem soil was carried in AO "Dubovoe" (Tambov region), the experimental plot on dark gray forest soil was located in OAO "Agronom-Sad" (Lipetsk region). Leaf samples for analysis were taken during periods of the highest demand for the appropriate nutrients: phosphorus at the end of May, nitrogen at the end of June, and potassium in mid-August. Soil samples were taken before orchard planting and in August of the 3rd year of the study. The negative impact of drip irrigation on the content of soil nutrients was noted: the acidity increased on the meadow-chernozem soil, in both types of soil the content of available nitrogen decreased, as well as phosphorus and potassium in the upper layers of the soil. The content of the main nutrients in the leaves under fertigation depended on the variety response to fertilization, as well as on the soil type: the Lobo variety had a higher content of the studied nutrients in the leaves when fertigated on dark gray forest soil. The Spartan variety had a higher content of nutrients in leaves during fertigation on meadow-chernozem soil. Fertigation had a significant effect on increasing the yield capacity of Lobo variety on dark gray forest soil, and the yield capacity of Spartan variety on meadow-chernozem soil.