Effects of ultrahigh frequency electromagnetic field and water deficit on spring wheat yields

Drought is one of the major limiting factors in crop growing especially in risky farming areas. The search for efficient, easy-to-implement and environmentally friendly ways to increase the adaptive abilities of plants through pre-sowing treatment remains relevant. One of these methods is exposure to ultrahigh frequency electromagnetic field. The research goal was to study the combined effect of the electromagnetic field of ultrahigh frequency and water deficit on spring wheat yields. In 2019 and 2020, during the greenhouse experiment, the conditions of drought (rainfall shelter) were simulated. The research targets were soft spring wheat seeds (Triticum aestivum L.) of the Novosibirskaya 31 variety. The experimental design included four treatment variants: 1) control, no treatment, normal moisture conditions; 2) no treatment, water deficit conditions; 3) pre-sowing treatment of seeds by ultrahigh frequency electromagnetic field, power 0.42 W, exposure 11 s, normal moisture conditions; 4) pre-sowing treatment of seeds by ultrahigh frequency electromagnetic field, water deficit conditions. Our experiments showed cereal response to the successive action of ultrahigh frequency electromagnetic field and drought. Under normal moisture conditions, the yield averaged 3.27 t ha. The treatment with ultrahigh frequency electromagnetic field resulted in yield gain of 31.5%. Water deficit leads to a 1.5-fold decrease of yield compared to the control. Pre-sowing UHF treatment eliminates water stress and yield loss: the difference is 11.3% compared to the control. Under the conditions of severe water deficit, wheat switches the flow of plastic substances and energy from growing processes to generative ones. The UHF treatment increases the kernel weight leading to the formation of more filled grains.