벼 알곡내 미량원소 함량 증진을 위한 시비방법

사란냐쿠푸사미 ( Saranya Kuppusamy ),윤영은 ( Young-eun Yoon ),김송엽 ( Song Yeob Kim ),김장환 ( Jang Hwan Kim ),이용복 ( Yong Bok Lee ) 한국환경농학회 2016 한국환경농학회 학술대회집 Vol.2016 No.-

Various strategies like application of fertilizers to soil are being proposed and pursued to increase the concentration and bioavailability of micronutrients in cereal grains like rice/wheat to meet human health requirements. To the best of our knowledge, so far no research has been published on how optimized, long-term fertilizer application (treatments: unfertilized/UF, NPK, compost and NPK + compost) affects the concentration of micronutrients in the milling fractions of rice grains (bran or edible grain part) with details of their dietary exposure upon consumption. In this study, we report results from a more than 45 years old field plot experiment conducted in the southern part of Korea. In general, long-term fertilization (NPK + compost > NPK > compost) had significant effect on grain As, B, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, V and Zn fortification, although it promoted the overall soil micronutrient density. The beneficial effects of intensive fertilization in our study on the micronutrient contents of the edible portion of rice (grain) seem to be related to the combined and continuous application of organic and inorganic fertilizers (Fig. 1). The highest contributors for micronutrient intake as demonstrated in our experiment could be the rice grains from the long-term NPK + compost fertilized plots (Fig. 2), however the estimated levels were still lower than the recommended dietary intake levels for micronutrients established by FAO/WHO. From our study, it is important to note that 70-75% of the micronutrients with important implications for human nutrition and health (Fe, Mn, Zn, Co, Ni, Se and V) are concentrated in the rice bran. Hence, long-term fertilization will not reasonably benefit the individuals who consume just the white rice, because the bran with enriched micronutrients will be removed by milling. We suggest to replace the consumption of white rice with brown rice to enable improved micronutrients for the individuals. In conclusion, optimized long-term application of compost with N, P and K chemical fertilizers to soils holds promise as a grain fortification strategy; but how micronutrient availability in rice grains changes with different v

논 토양에서 무기질비료 장기연용에 따른 정조내 양분함량 변화

사란냐쿠푸사미 ( Saranya Kuppusamy ),윤영은 ( Young-eun Yoon ),김송엽 ( Song Yeob Kim ),김장환 ( Jang Hwan Kim ),이용복 ( Yong Bok Lee ) 한국환경농학회 2016 한국환경농학회 학술대회집 Vol.2016 No.-

Soil fertility directly influence the essential micronutrient contents of crops. In this study, attention was given to the role that long-term inorganic fertilization can play in increasing the micronutrient output of the paddy cropping system. After more than 45 years of inorganic fertilizer application (treatments: unfertilized/UF, N, P, K, PK, NP and NK fertilized soils), combined application of fertilizers substantially increased As, B, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, V and Zn density in the soil and rice grain compared to the control plots and that received single fertilizers. Combined application of PK followed by NK and NP fertilizers significantly enhanced the total and potentially bioavailable fractions of the investigated micronutrient contents in the soil. Optimized and continuous application of PK fertilizers increased the overall micronutrient densities in the rice milling fractions (both grain and bran). Micronutrient concentrations were usually highest in the bran and lowest in the grain. Notably, both the rice bran and grain were rich in Fe, Mn and Zn contents (Figure 1). Though long-term fertilization enhanced the proportion of micronutrients in the rice grain, the levels were still much lower than the recommended dietary intake levels for micronutrients. We hence, suggest high intake levels, relatively high brown rice consumption (with micronutrient dense bran layer) which may still modestly increase the daily intake level of micronutrients and could help to meet the nutritional requirements for a sound health. Correlation analysis indicated that soil pH and organic matter exerts a significant and direct effect on the micronutrient concentration of rice. The results of this study also suggest that, soil total/bioavailable micronutrient content, as well as other soil properties such as available P, should be taken into account for precisely predicting micronutrient contents in rice plants under field conditions.

논 토양에서 장기연용 시비가 유용 미생물 군집구조에 미치는 영향

김장환 ( Jang Hwan Kim ),사란냐쿠푸사미 ( Saranya Kuppusamy ),김송엽 ( Song Yeob Kim ),윤영은 ( Young-eun Yoon ),이용복 ( Yong Bok Lee ) 한국환경농학회 2016 한국환경농학회 학술대회집 Vol.2016 No.-

Balanced fertilization stimulate the beneficial soil microbial abundance, diversity and activity, and ultimately enhance the soil health as well as crop yield. In this study, forty-five years of fertilizer application (compost, NPK, NPK + compost, PK, NK and NP) in a paddy field soil in South Korea significantly altered the beneficial soil bacterial community structures, as assessed by pyrosequencing analysis. The major classified bacterial phyla for all treatments were Proteobacteria, Actinobacteria, Cyanobacteria and Firmicutes with nutrient cycling potential. Major changes in the community composition of the Actinobacterial orders was not evident in the fertilized soils. However, positive influence of fertilization on the abundance of rest other dominant phyla were found. The known N-fixing and P-solubilizing Cyanobacteria, Thiobacillus, Rhizobium, Pseudomonas and Bacillus diversity and richness significantly increased under long-term mineral and/or organic fertilizer applications, such as NP, PK, compost and NPK + compost. Supported by high throughput sequencing approach we hereby propose that the mechanism of N and P cycling under long-term balanced fertilization in a rice ecosystem is largely governed by microbes, notably by the free living N-fixing and/or P-solubilizing heterocystous and/or non-heterocystous cyanobacteria, autotrophic bacteria and heterotrophic bacteria. Further, the current study warrants that balanced fertilizers may be used without detrimental effects on agricultural soils in the long-run. This knowledge would be valuable towards the better understanding of effective fertilization on the beneficial microbial community in agro-ecosystem (Table 1).

장기연용 시비가 논 토양의 미생물 군집구조 변화에 미치는 영향

김송엽 ( Song Yeob Kim ),사란냐쿠푸사미 ( Saranya Kuppusamy ),김장환 ( Jang Hwan Kim ),윤영은 ( Young-eun Yoon ),이용복 ( Yong Bok Lee ) 한국환경농학회 2016 한국환경농학회 학술대회집 Vol.2016 No.-

Using 454 pyrosequencing of 16S rRNA genes, the current study investigated how bacterial succession changed under different fertilizer regimes (unfertilized, compost, NPK, NPK + compost, PK, NK and NP) in a more than 45 year old paddy field trial (Figure 1). Of the selected treatment variables, application of compost enhanced soil fertility. Notably, long-term fertilization had no significant effects on soil microbial structure in paddy soils. The dominant bacterial communities were Proteobacteria and Chloroflexi. Further, Actinobacteria and Firmicutes were substantially abundant in the compost and NPK + compost treatments. Findings of this study highlight that organic fertilizer amendment activates diverse groups of Gram positive microorganisms as compared with conventionally used chemical fertilizers. Abundance of Rhizobiales that directly influences rice growth through symbiosis or indirectly through nutrient cycling, and Methylococcales that combat greenhouse gas (methane) emission were high in treatments that received compost as compared to inorganic fertilizers amended and unfertilized treatments. This could further indicate that organic fertilizer may be used without detrimental effects on the promising soil microbial diversity in the long-term. Thus, long-term organic fertilizer application have a reasonable impact on beneficial bacterial community inhabiting the soil for the prospects of crop yield.