Assessment of the biostimulative effect of Lithovit and Kelpak on selected biometric and qualitative features of winter oilseed rape

Abstract

Biostimulants are products that can modify physiological functions of plants, strengthen plant natural defenses against different biotic and abiotic stresses and improve nutrition efficiency. They can help plants to adapt to unfavorable conditions by either suppressing or eliminating plant growth-limiting factors affecting plant during its life. Seaweeds are the most essential living organisms used commercially as biostimulants on a wide scale. Fertilizers containing numerous microelements are another group affecting positively plant response to environmental stress. Field trials evaluating application of two biostimulants were carried out at the Institute of Plant Protection – National Research Institute in Poznan (Poland) in the 2011–2013. The aim of the study was to assess the influence of carbon dioxide leaf fertilizer (Lithovit) and seaweeds (Kelpak) applied separately or in the mixtures on winter oilseed rape plants. The results obtained in the study confirm the significant impact of weather conditions on seaweeds and nanofertilizer activity. Positive effect of the examined substances on plant height, chlorophyll content, number of seeds in pods, mass of 1000 seeds and yield was revealed in the year with worst humidity conditions. Kelpak and Lithovit activity was more beneficial to oilseed rape when used at the earlier plant growth stage (BBCH 32), regardless of whether the products were applied separately or in a mixture. The type of biostimulator (algae extract or mineral biostimulator) was not a factor determining its effect on winter rapeseed plants.