Nutrient Supply Ability of Hairy Vetch and Rye as Green Manure in Organic Farming System.
Sang-Min LEE, NIAST, 250 Seodundong Kwonsungu, Suwon, South Korea
Crop rotation is prescribed for an essential practice in organic farming. Farmers cultivate some green manure crops during winter season to supply demanded nutrients for crop cultivation. The objectives of this work is to evaluate whether hairy vetch and rye as fertilizer source have a potential ability for the normal growth of red pepper and green onion. On a basis of dry matter shoot biomass of hairy vetch and rye was harvested from 3,001 to 4,080 kg per ha and from 4,082 to 4,190 kg per ha, respectively. Shoot/root ratio of hairy vetch and rye based on dry matter was 1.91 and 0.88, respectively. Expected root biomass obtained from shoot/root ratio ranged from 1,571 to 2,136 kg per ha in hairy vetch and from 4,639 to 4,762 kg per ha in rye. Considering above estimated results, the possible amount of nitrogen, phosphorus and potassium provided from rye residue addition was 64 to 66, 65 to 67 and 182 to 187 kg per ha, respectively, and those from hairy vetch had 118 to 160, 59 to 81 and 159 to 216 kg per ha. Key words : Hairy vetch, rye, organic farming, shoot/root ratio, nutrient supply.