The article presents the results of field studies of the collection gene pool of spring barley in the conditions of the Ryazan branch of the Federal State Budgetary Scientific Institution "Federal Scientific Agroengineering Center VIM" in 2017-2021 against the natural background of the development of fungal diseases. The aim of the research was to carry out immunological clustering of the collection gene pool of spring barley in the conditions of the Ryazan region and to identify the most promising forms for inclusion in crosses as parental forms. It was revealed that the vast majority of the studied varieties belonged to the group of highly resistant varieties. It was found that more than half of the varieties (57.8%) of the studied collection possessed complex resistance to a group of pathogens (reticulated (Perenophora teres Drechs), dark brown mottling (Bipolaris sorokiniana Shoem), powdery mildew (Erisiphe gramminis D.C.f.sp. hordei Marchal), dusty smut (Usnilago nuda Jen.)). spring barley. The following varieties showed high complex stability: Nur, Reliable, Moskovsky 3, Moskovsky 2, Dvina, Kalita, Hopper, Clear, Griv, Miar, Risk, Choice (Russia); Timerkhan (Tatarstan); Divosny, Gonor, Yakub, Batka, Fest, Khago (Belarus); Hetman, Kharkiv 102, Vinnytsia 17 (Ukraine); Ilek-1, Ilek-34 (Kazakhstan); Delphin (France); Linga, Irbe (Latvia); Izotta, Graice (Germany); Prosa, Pejas (Czech Republic); Collie (UK); B-934 (Canada). The greatest approximate productivity over the years of research has been revealed in the following varieties: Notable (Russia), Gonar (Belarus), Vivaldi (Austria), Eufel, Pioneer (France), Stratus (Poland), which have an advantage over the Yaromir standard by 0.3 – 0.7 t/ha. Reliable variety (Russia) had the highest resistance to lodging out of the entire studied gene pool of spring barley – 8.6 points. The use of a comprehensive ranking assessment revealed the priority of varieties of the Belarusian selection Divosny, Gonar and Czech varieties Pegas, Prosa, which occupy leading positions on the rating scale in terms of resistance to lodging, disease damage and productivity.

The article presents the results of studies of the biological effectiveness of gibberelinic acid in the technology of cultivation of spring rapeseed, conducted in the conditions in 2019–2021. The purpose of the research is to identify the effect of gibberellic acid (GC) on the yield and quality of spring rapeseed oil seeds in the conditions of the forest-steppe zone of the Ryazan region. A clear advantage in the safety and overall survival of rapeseed plants for harvesting with the use of GC was revealed. It was found that the use of GC affected the date of the onset of the phenophases of the culture in the moistened year, reducing the growing season by 3 days. In a dry year, with a low vegetative mass, it did not have a significant effect. The use of GC had a positive effect on the structure of the spring rapeseed crop. The number of branches of the 1st order increased with the use of GC growth by 21,2-42,8 %, the number of pods by 5,9-25,0 %, the number of seeds from one pod by 8,3-52,2 %, the mass of seeds from the 1st plant by 20,6-28,0 %, the number of seeds from the 1st plant by 14,7-18,8 %, the mass of a thousand seeds by 5,5-17,5 %. The yield of oilseeds after the use of GC increased by 26,7-29,1 %. Processing of GC crops provided a reliable increase in yield by 2,6-3,2 c/ha, compared with the control in all years of research. The oil content of the seeds did not have a significant deviation from the control.