Title: The Effects of Barley-Hairy Vetch Mixtures on Green Manure Productivity and Soil Phosphorus Solubilization
Abstract: Soil phosphate accumulation has been problems in some organic farmlands in Korea.This study was conducted to solubilize the accumulated phosphate in organic upland soils using green manure mixtures as substitute for chemical materials (EDTA etc.).We investigated the effects of barley-hairy vetch mixtures on the productivity of biomass and nutrient and the solubilization of soil phosphate.Treatments were barley single (B), hairy vetch single (H), mixtures of B and H at the ratio of 2:1 (B2H1), 1:1 (B1H1), 1:2 (B1H2), and control (CON).Green manures were cultivated on phosphate accumulated soils (>1,000 mg Lancaster P 2 O 5 kg -1 ) for 3 years.Mixtures were more effective for stable production of yields and nutrient than B or H, because dry matter yields of green manures were more variable in B and H single.The quality of B as green manure improved in mixtures, because the C/N ratio of B in mixture increased less than B single.In addition, H was effective for phosphate solubilization, as water soluble phosphate contents of H single (2017 and 2019) and mixtures (2019) were significantly higher than B single (2017 and 2019) and CON (2019) despite of phosphate uptake by green manures.Therefore, barley-hairy vetch mixtures could be useful considering green manure productivity and phosphate solubilization in phosphate accumulated upland soils.