The authors present the results of the study of pears clonal rootstocks, namely the following quince forms: IC 2-10, IC 4-6, S1 and Cydo in the nursery during 2010-2012. Experimental nursery was founded in the spring of 2010, with bushes planting designs of the following dimensions: 1,4*0,3 m. Diameter of the reference root collar of all forms of rootstocks in average over the years of the tests, ranged from 6,7 mm to 7,9 mm and satisfied the requirements of standard (6-12 mm). Among the quince forms under review the best biometric indicators for two years of examination have been registered for IC 2-10, IC 4-6 and S1quince. The IC 4-6 and S1 display better quality of the root system of vertical layers; highest standard layers yield is registered for ІC 2-10, 4-6 and S1forms. IC 2-10 rootstock and S1quince have proved to be the best varieties for the West Steppe of Ukraine by the complex of economic and biological characteristics.

The authors present the results of the study of pears clonal rootstocks, namely the following quince forms: IC 2-10, IC 4-6, S1 and Cydo in the nursery during 2010-2012. Experimental nursery was founded in the spring of 2010, with bushes planting designs of the following dimensions: 1,4*0,3 m. Diameter of the reference root collar of all forms of rootstocks in average over the years of the tests, ranged from 6,7 mm to 7,9 mm and satisfied the requirements of standard (6-12 mm). Among the quince forms under review the best biometric indicators for two years of examination have been registered for IC 2-10, IC 4-6 and S1quince. The IC 4-6 and S1 display better quality of the root system of vertical layers; highest standard layers yield is registered for ІC 2-10, 4-6 and S1forms. IC 2-10 rootstock and S1quince have proved to be the best varieties for the West Steppe of Ukraine by the complex of economic and biological characteristics.

Purpose. To identify the productivity of the genus Salix L. plants and study the relationship between its structural elements. Methods. Field study, laboratory analysis, analytical approach. Results. It was found that the height of a three-year plants of species ranged from 86.0 to 775.1 cm, of hybrid forms – from 197.0 to 488.0 cm. Average diameter of three-year plants varied in the range of 19.10 to 52.94 mm (species) and from 28.04 to 49.23 mm (hybrid forms). The highest stability for complex of morphological characters was observed in bog willow samples. It was determined that among species basket willow (16.94 t/ha) and white willow (21.19 t/ha) were the most productive for dry biomass yield per 1 hectare, among hybrid forms – purple willow × basket willow (23.36 t/ha) and basket willow × bog willow (18.57 t/ha). It was established that the value of the plants productivity was characterized by moderate, significant and close correlations with the average diameter of plants, length and number of shoots of the second order. Conclusions. A comprehensive assessment of productivity traits of three-year plants from willow collection was conducted, index of dry matter yield per 1 hectare was defined. The links between quantitative traits that characterize the contribution of some of them in productivity index were investigated. Method of cluster analysis was used to group samples for the similarity of complex agronomic characters. Basket willow and white willow as well as such hybrid forms as basket willow × bog willow and purple willow × basket willow were recommended to use as a source material for selection of samples with high productivity.