PRODUCTION OF SEEDLING AND GROWTH OF HOPS ON SOIL UNDER DIFFERENT PH VALUES AND POTASSIUM RATES

Abstract

Hops (Humulus lupulus) is a plant with potential for cultivation in the Center-South region of Paraná, Brazil. However, there are no official Brazilian recommendations for production of seedlings or fertilization and liming. The aims of this work was to evaluate the production of hop seedlings and verify the development of hop plants grown in soil with different pH values and K₂O rates, in the Center-South region of Paraná, Brazil. Three experiments were carried out: i) cuttings of a plant were dipped in a 1% indole-3-butyric acid (IBA) solution and placed in different substrates – here was verified the sprouting and survival of the hop seedlings; ii) hop seedlings were transplanted to a soil with different pH values (4.5, 5.5, 6.0 and 6.5) – the development and nutrients uptake by the plants was evaluated; iii) hop seedlings were transplanted to a soil with different K₂O rates added – the development and K uptake by the plants was assessed. The substrate for seedling production did not influence the sprouting of hop cuttings, but the presence of IBA reduced sprouting and growth up to 41 days. The pH 5.5 value in the soil provided the best hop development by increasing the production of fresh and dry biomass in comparison with pH 4.5. Hop plants in soil with pH 6.0 and 6.5 showed lower chlorophyll content, but maintained the same nutrient uptake. The production of dry biomass of hop plants and the K content of the roots increased with the K₂O rates added to the soil, However, K was not transferred to the aerial part of the plants in the initial phase of development.