Koretskiy A. Soybean breeding for resistance to downy mildew

The formation process of productivity and quality of soybean seeds for cultivars with different resistance to downy mildew depending from conditions and receptions of agro technology. Improvement of creation methods of high productivity of soybean cultivars resistance to downy mildew on the foundation of estimation of distribution and development of the disease within of northern Forest and Steep zone of Ukraine. The research methods are field, measuring and weighing, electrophotometric, chemical, mathematical and statistical, calculated-comparative. The plant breeding forms resistance to downy mildew are selected; inheriting stability for hybrids and influence of vegetation period duration and thickness of the cuticle on formation of this mark is defined. The possibility of decrease of the defeat soybean in primary links of seed breeding is proved at execution of the complex of technological methods, such as sowing in optimal periods (first decade of May), wide-rowed (row space 0.45 m), with norm of sowing 550-600 thousand vitae seeds on ha, with rotation of the crop is not more often, just per 4 years and to contain plantations clean from weeds. The guidelines designed for provide improvement of effectiveness of plant breeding work with soybean at creation new high productivity of soybean cultivars resistance to downy mildew, which provides increase of productivity on 0.3-0.4 т/ha. Selected resistances to downy mildew varieties were industrial check in Bukovinsky institute of AIP of UAAS, Plant breeding and genetic institute of UAAS and Institute of agriculture of UAAS. High productivity of soybean numbers resistance to downy mildew was used for hybridisation in plant breeding work. The field of application are plant breeding and agriculture.