Formation of yield of hybrid corn Khorol SV depends on the application of chemical protective measures during hybridization

Aim. To improve the yield of the hybrid and parental components of corn seeds by applying biological products and chemical protective agents at optimal times. Methods. The experiment was conducted on plots of the hybrid corn Khorol SV, the maternal component Uk Pg 103 and the parental Uk 26 SV. During the research, the field experiment method, weight, calculation and statistical methods were used. Results. The experimental scheme includes factors: treatment with the fungicide Acanto Plus, treatment time, castration method or without castration, use of the drug «Biogel», which together amounted to 24 options. The experimental plots were treated twice with the drug Biogel before sowing. The application rate for foliar treatment of crops is 2 l/ha. During the growing season, corn on the experimental plots was treated with the fungicide Acanto+, which is effective against helminthiasis and rust, according to the experimental scheme. The application rate is 1 l/ha. Conclusions. It was established that in 2021–2023, with double treatment with the fungicide Acanto+ and use of the drug «Biogel», compared with the control in the maternal component UkPg 103 C, the increase in the disease was not in all forms of castration. To a greater extent, the disease decreases from the control (–). With manual castration (prevalence –1.5%, development –3.23%), mechanical (prevalence –1.1% development –2%), without castration (prevalence 0.33% development –1.3%), with respect to vesicular smut. The decrease in the prevalence (–43.3-50%) and the development of the disease from the control occurred with all forms of castration (manual –2.43%, mechanical –2.23%, without castration –0.7%). The decrease in the prevalence of vesicular smut also occurred in the parent component Uk 26 SV, the prevalence with all forms of castration: manual (prevalence –2.5% development –3.03%), mechanical (prevalence –2.17% development –2.63%), without castration (prevalence –1.34% development –1.5%). The prevalence of vesicular smut was lower by –40–50%. The decrease in the development of the disease from the control occurred with manual –1.93% form of castration, mechanical –1.77% and without castration –1%. Hybrid Khorol SV the decrease in the damage by soot occurred in the spread with manual and mechanical forms of castration and development with all forms of castration. The form of castration is manual (spread –0.33% development –1.07%), mechanical (spread –0.44% development –0.94%), without castration (spread 0.17% development –2.37%). The development of helminthiasis manual -30%, without castration –0.33, mechanical prevailed over the control 0.1%. Regarding the effectiveness of castration methods or forms, on average, for all options for treating crops with Akanto+ and/or Biogel, mechanical castration contributed to an increase in seed yield by +1.3 t/ha or 10.8%, manual castration by +1.2 t/ha or 10.1% compared to crops where castration was not performed. That is, castration has a positive effect on yield. The greatest increase in yield was obtained with two-time treatment with the fungicide Akanto+ and Biogel before and after castration – +1.99 t/ha or 15.9%.