• Korean Journal of Environmental Agriculture
• /
• v.32 no.4
• /
• pp.268-272
• /
• 2013

BACKGROUND: The mixtures of legumes and non legumes can be an efficient tool to combine the benefit of the single species in the cover crop practice. However, there is a lack of information on how the species proportion may affect N accumulation and how this can influence the nitrogen use of subsequent rice production. METHODS AND RESULTS: In this study barley and hairy vetch was selected as a green manure. The pure stands or mixtures with different seeding ratios was tested on green manure N accumulation and its following rice cultivation. Total aboveground biomass and N accumulation of mixture were higher compared to that of pure barley and hairy vetch. Among the mixtures, the highest aboveground biomass (8.07 Mg/ha) and N accumulation (131 kg/ha) was observed in B75H25 (barley 75% + hairy vetch 25%). The N accumulation of the mixture ranged from 99 kg/ha to 131 kg/ha which was much higher than amount of recommended (90 kg/ha) for rice. All mixture (barley 75%+hairy vetch 25%, barley 50%+hairy vetch 50%, barley 25%+hairy vetch 50%) produced 7-8% more rice yield than the conventional cultivation (NPK). The rice yield of in barley monocrop was 4% less than that of NPK. COLCLUSION(S): Adopting mixtures of barley and hairy vetch could be efficient strategy for rice production as an alternative of nitrogen fertilizer.

• Applied Biological Chemistry
• /
• v.24 no.4
• /
• pp.230-237
• /
• 1981

For the investigation of efficient use of fertilizer nitrogen NPK simple trials were carried out using newly bred Tongil line(japonica indica hybrid selection) and the leading local varieties with sulfur coated area in fields for two years. The yield of Tongil line was higher than that of leading local varieties by 16% in the cool year and 23% is warm year with high solar radiation from NPK simple trials including SCU and 2-split application which were carried in 130 fields at 32 locations. Warm year increased yield by 9% in Tongil but only 3% in the local than the cool year did. Optimum nitrogen level was higher in Tongil by 3.8㎏ in the cool year and 5.5㎏ in warm year than for the local. Yearly variation of optimum nitrogen in the carne variety was greater than varietal variation in the same Year. Two-split application resulted in 1 to 2% of inconsistent yield variation. Sulfur coated urea increased yield by average 2 to 4% even at 20% reduced rate of nitrogen. It was remarkably effective in same $(27{\sim}39%)$, virgin (20%) and unmatured (10%) soils.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.7 no.1
• /
• pp.31-42
• /
• 1999

To investigate the effects of the composts made of sewage sludges on the physico-chemical properties of soil and growth of paddy rice, the variations of chemical properties in soil, the contents of inorganic matters and heavy metals in plant tissues, the contents of heavy metals in brown rice, the growth response of paddy rice and grain yield were investigated. The results were summarized as follows : The contents of organic matters, N, available $P_2O_5$ and exchangeable K in soil were increased by application of the composts. The contents of N and available $P_2O_5$ in soil were remarkably decreased at the harvesting time in comparing with the 20th day after application of the composts. The contents of heavy metals in soil were increased very slightly by application of the com-post. At the harvesting time, the contents of N and K were not varied in all plant tissues at the plot of the compost in comparing with the plot of the NPK. The content of $P_2O_5$ in plant was increased by application of the composts. The contents of heavy metals in plant tissues and brown rice were not changed among the treatments. When the composts were applied to the pot at the rates of 1,000, 2,000, 4,000 and 6,000kg/10a with NPK, the numbers of grain yield were increased with 3, 18, 44 and 54% in comparing with NPK plot, respectively. Dry weight, the numbers of tillers and spikelet of the rice plant were increased by application of the composts.

• Food Science and Preservation
• /
• v.10 no.1
• /
• pp.75-79
• /
• 2003

Total nitrogen(TN) contents in all samples were in the range of 308.3 to 925.9 mg% and TN value of kanjang prepared with high pressure(HPK)-heated bean was lower than that of normal pressure(NPK) and steam(SPK)-heated bean. TN content was slightly increased according to the heating time of bean. Amino type nitrogen(AIN) contents in all samples were in the range of 133 to 451.5 mg％ and AIN value of NPK(451.5 mg%) was higher than that of HPK(133∼171.5 mg%) and SPK(178.9∼224 mg%). Ammonia type nitrogen(AON) contents in all samples were in the range of 23.5 to 142.0 mg% and AON value of HPK was lower than that of HPK and SPK. Free amino acid(FA) contents in all samples were in the range of 133 to 451.5 mg%, and then FA content of NPK was higher than that of SPK(178.9∼224 mg%) and HPK(133 ∼171.5 mg%). Lightness(L) value of Hunter color in all samples were in the range of 45.13 to 49.08 and was similar with each other. Redness(a) and yellowness(b) value were in the range of 25.30∼34.43 and 52.55∼74.13, respectively.

• Korean Journal of Environmental Agriculture
• /
• v.35 no.1
• /
• pp.39-45
• /
• 2016

BACKGROUND: This study aimed to evaluate the combined effects of three components (NPK) of chemical fertilizers with basal application of compost on soil organisms.METHODS AND RESULTS: The soil was treated with five treatments continuously for 15 years: control, PK, NK, NP and NPK. The application of N increased plant growth or biomass, and enhanced organic matter content in the soils. Levels of microbial phospholipid fatty acids (PLFAs) in the soils did not show marked differences among the soils treated with different treatments. However, the principal component analysis showed the changes in the structure of the microbial community in the soil, depending on treatments added. Nitrogen application caused a decrease of pH and an increase of EC in the soils, and these environmental stresses appeared to offset the promoting effect of increased organic matter content on microbial abundance. The abundance of bacterivorous nematodes was the highest in the soils after treating NPK; however, the abundance of fungivorous nematodes was unaffected. There was no significant correlation between the abundances of microbial groups and their feeders. Organic matter content was significantly correlated with the abundance of nematodes in the soils.CONCLUSION: Our results showed that chemical fertilizers affect the soil food chains through both biotic and abiotic factors, and a trophic cascade in the soils may not occur in response to long-term fertilization.

• Korean Journal of Environmental Agriculture
• /
• v.31 no.4
• /
• pp.308-312
• /
• 2012

BACKGROUND: The nutrient balance in Korea during 1985-2006 had continually increased and maintained the highest levels among OECD countries. The use of green manure crops such as barley and hairy vetch is common practice for reducing chemical fertilizer application and maintaining soil fertility. However, green manure crops can also be used as a livestock feeding material which may reduce nutrient balance in the national scale. We calculated nitrogen and phosphate balance under green manure-rice cultivating system where all green manure was removed and used for feeding livestock. METHODS AND RESULTS: The barley and hairy vetch grown in pure stands or in mixtures with different sowing rates were tested for rice cultivation without chemical fertilization. The conventional fertilization (NPK) for rice cultivation was selected to compare nutrient balance with green manure-rice cultivation. Nitrogen and phosphate balance were calculated according to the surface balance method of the PARCOM guidelines. Total aboveground biomass of mixture (barley and hairy vetch) was higher compared to that of pure barley or hairy vetch. Among the mixture with barley and hairy vetch, the highest aboveground biomass was observed in B75H25 (barley 75%+hairy vetch 25%). The nitrogen and phosphate balance in the B75H25 mixture was-104 kg N/ha and-50.3 kg P/ha, respectively. CONCLUSION(S): The barley and hairy vetch mixture proved to be a very effective strategy for biomass production of green manure. The amount of nitrogen and phosphate fertilizer to be applied is estimated to be 104 kg N/ha and 50.3 kg P/ha in order to maintain soil fertility if all green manure and rice straw were removed from rice field for livestock feeding.

• Research in Plant Disease
• /
• v.12 no.2
• /
• pp.108-114
• /
• 2006

This study was conducted to elucidate the interactions among soil microorganisms in a special field where one, two or three of N, P, K fertilizers were continuously not applied for 29 years. Crop yield (barley, soybean), soil chemical properties and microflora and microfauna including nematodes, nematophagous fungi, actinomycetes, bacteria, and fungi were examined for two years. Tylenchorhynchus sp. was the most important plant-parasitic nematode (range $11{\sim}642/300 cm^3$ soil) followed by Pratylenchus sp. and Helicotylenchus sp. Among nematophagous fungi, Monacrosporium spp. was the most frequently found followed by Harposporium sp. and Cystopage sp. In general, plots treated with phosphate fertilizer yielded more, had more nematodes, bacteria and actinomycetes. In contrast, total fungal population densities including nematophagous fungi, Cystopage sp. and Harposporium sp. were in reverse; they were more abundant in the plots with lower phosphate contents. Phosphate and pH are positively correlated and two most important determining factors for the population density of soil organisms under investigation. According to correlation analysis, Ca, Mg, and $SiO_2$ contents in soil and population densities of Tylenchorhynchus sp., saprophitic nematodes, actinomycetes, and bacteria were positively correlated with pH, but were negatively correlated with fungal population densities. We hope that the study will add an additional knowledges to understand our mysterious underworld.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.15 no.2
• /
• pp.93-100
• /
• 1995

This experiment was carried out to investigate how to effect the application of nitrogen, phosphate and potassium on the vegetation and dry matter yield in the mixed sward of orchardgrass and crabgrass (Digitaria sanguinalis [L.] Scop.). The experimental sward wa5 consisted of eight plots of non-application, P, K, PK, N. NK, NP and NPK. These plots were sown with seeds mixture of orchardgrass 17.5 kglha and crabgrass 17.5 kg/ ha on 22 April 1975 in the forage experimental field of Kangwon National University, Chunchon, Korea, and were cut four times from 6 July to 18 November 1975. The results obtained were summarized as follows: 1. In orchardgrass density measured after summering, the plot of nitrogen applied without phosphate marked only 3 1.0% of the plot of nitrogen applied with phosphate while in crabgrass density measured at that time the plot of nitrogen applied without phosphate marked as high as 112.5% of the plot of nitrogen applied with phosphate. 2. Application of phosphate and potassium improved wintering record of orchardgrass. In orchardgrass density measured after wintering, the plot of nitrogen applied without phosphate marked only 9.7% of the plot of nitrogen applied with phosphate, and the plot of NP applied without K marked 63.6% of the plot of NP applied with K. 3. In surface coverage of orchardgrass, in midsummer any plot applied with nitrogen regardless of accompanying with or not with phosphate wa5 0%, but in autumn the plot of nitrogen applied with phosphate was 56-58% and the plot of nitrogen applied without phosphate was 5%. While after wintering the plot of nitrogen applied with phosphate was 28-37% though the plot of nitrogen applied without phosphate was only 0.3-0.6%; the application of phosphate improved summering and wintering record of orchardgrass. 4. Application of phosphate demonstrated remarkable effect on increasing dry matter yield in orchardgrass. In year total yield of orchardgrass, the plot of nitrogen applied without phosphate marked as low as 11.3% of the plot of nitrogen applied with phosphate, but in crabgrass the plot of nitrogen applied without phosphate was almost equal to the plot of nitrogen applied with phosphate showing 97.5% of this plot. 5. Application of potassium was not effective on increasing dry matter yield of orchardgrass but its application was effective on increasing dry matter yield of crabgrass. In dry matter yield of orchardgrass significant difference was not found between NP plot and NPK plot, but in dry matter yield of crabgrass NPK plot recorded significantly higher yield compared with NP plot (p<0.05). 6. In botanical composition of the plot of nitrogen applied with phosphate, crabgrass recorded 46.5-50.5% in early summer (July) but in midsummer (August) it dominated the plot recording 85.6-91.2%. 7. In botanical composition based on the year total yield, in the plot of nitrogen applied with phosphate orchardgrass marked 21.7-26.2% and crabgrass recorded 73.8-78.370, but in the plot of nitrogen applied without phosphate orchardgrass marked only 3.5% being overwhelmingly dominated by crabgrass which recorded 96.5%. 8. Application of nitrogen not accompanied with phosphate strengthened competitive power of the crabgrass unilaterally, making orchardgrass be oppressed fatally by the crabgrass.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2006.04a
• /
• pp.434-435
• /
• 2006

• 한국약용작물학회:학술대회논문집
• /
• 2008.05a
• /
• pp.85-86
• /
• 2008