The promotion of cotton in regions with long daylight hours is a priority for genetics. The creation of a new breeding material for a crop with a short growing season of 95-110 days makes it possible to organize the production of this fiber in the south of Russia. The studies were carried out in 2014-2020 at the experimental sites of the Volgograd State Agrarian University. Growth, development, ecological and biological characteristics were studied on new cotton varieties PGSSH 1 and PGSSH 7 in conditions of light chestnut soils. Field experiments were carried out according to generally accepted methods. As a result, it was found that the growing season of new varieties of cotton corresponds to the conditions of the season in the Volgograd region. Boll opening is celebrated from 25 August to 20 September. Bushes form 4 to 18 fruits, 58% are located in the middle tier. The limiting growth and development factors include sharp drops in daytime and nighttime temperatures in spring (up to 150C). In some years, cold and rainy weather in July leads to the development of diseases on plants. However, new varieties of cotton have time to mature and form high quality fiber. Hot, dry weather does not adversely affect plant growth and development. The potential yield of these varieties reaches 3.3-3.5 t / ha. These varieties have good prospects for implementation. The development of varietal agricultural technology will ensure the organization of cotton production in areas with long daylight hours.

The relevance of the study of mycoses is increasing due to their widespread distribution. Field experiments were carried out on sites in the region with short daylight hours (Dagestan) and long daylight hours (Volgograd). Fungal diseases were investigated on crops with short daylight hours: cucumber, pepper, and cotton according to the methods generally accepted in phytopathology. The species composition of aboriginal and exotic infections was revealed. Each culture under conditions of long daylight hours is characterized by damage by 4-5 species of fungi. The manifestation of exotic infections is observed at the beginning of the growing season at the seedling stage. The role of the introduction of short-day plants to the northern regions in the spread of exotic species of pathogenic fungi is shown. The species composition of fungi on crops in the study areas was found to be identical. They belong to different biological groups, but saprotrophs, biotrophs and hemibiotrophs predominate. It was found that Fusarium lolii (Wm.G. Sm.) Sacc and Rhizoctonia solani Kuehn (on cotton) and Verticillium dahliae Kleb and Rhizoctonia solani J.G. moved to new areas together with seeds. Kuhn (on pepper). These species are capable of causing epiphytotics at the beginning of the growing season with a low natural infectious background. The accumulation of native species of infection in the lands adjacent to the fields during the cultivation period leads to the appearance of epiphytoties in the second half of the growing season. First of all, the assimilation apparatus, flowers, ovaries and fruits are affected.