Cover cropping and liquid manure application are considered as effective ways to replace the use of chemical fertilizer in orchard. This study was conducted to investigate the effect of cover crop species and liquid manure application rate on green manure production, leaf mineral content, fruit quality and soil chemical properties in pear orchard. The treatments include rye and hairy vetch as cover crops, two liquid manure application levels based on N and K 2 O requirement on each cover crop species, and chemical fertilizer as control. Green manure production was higher in hairy vetch than in rye. K content of pear leaves and soil exchangeable K content increased in N based liquid manure application treatments. The yield was higher in rye + liquid manure and fertilizer treatments, and fruit quality was not different between the treatments. Taking all of these into account, rye + K 2 O requirement-based liquid manure application is recommended in pear orchard for not only sufficient nutrient supply but also prevention of any problem related with soil K 2 O accumulation in pear orchard in long-term perspective.

Many organic fruit growers adopt cover cropping in their orchards to improve soil properties. A field experiment was conducted to determine the effects of cutting frequency of cover crop (CF) and liquid manure application (LM) on green manure production (GMP) and returnable nutrient content (RNC) in pear orchard. The combined effects of CF and LM were tested at two levels, respectively, with liquid manure (L 1 ) and without liquid manure (L 0 ). After that, cover crops were cut once (C 1 ) and three times (C 3 ) in rye, and twice (C 2 ) and four times (C 4 ) in hairy vetch. The result showed that main factors related to green manure production were different depending on the species. In rye, LM was more effective in increasing the dry weight of cover crop and RNC than CF. In contrast, the parameters were more affected by CF rather than LM in hairy vetch. Thus, it is suggested that different management technique is needed depending on the cover crop species in order to maximize the green manure production in pear orchard.