• Journal of Microbiology and Biotechnology
• /
• 제32권10호
• /
• pp.1292-1298
• /
• 2022

Soil autotrophic bacterial communities play a significant role in the soil carbon (C) cycle in paddy fields, but little is known about how rhizosphere soil microorganisms respond to different long-term (35 years) fertilization practices under double rice cropping ecosystems in southern China. Here, we investigated the variation characteristics of rhizosphere soil RubisCO gene cbbL in the double rice ecosystems of in southern China where such fertilization practices are used. For this experiment we set up the following fertilizer regime: without any fertilizer input as a control (CK), inorganic fertilizer (MF), straw returning (RF), and organic and inorganic fertilizer (OM). We found that abundances of cbbL, 16S rRNA genes and RubisCO activity in rhizosphere soil with OM, RF and MF treatments were significantly higher than that of CK treatment. The abundances of cbbL and 16S rRNA genes in rhizosphere soil with OM treatment were 5.46 and 3.64 times higher than that of CK treatment, respectively. Rhizosphere soil RubisCO activity with OM and RF treatments increased by 50.56 and 45.22%, compared to CK treatment. Shannon and Chao1 indices for rhizosphere soil cbbL libraries with RF and OM treatments increased by 44.28, 28.56, 29.60, and 23.13% compared to CK treatment. Rhizosphere soil cbbL sequences with MF, RF and OM treatments mainly belonged to Variovorax paradoxus, uncultured proteobacterium, Ralstonia pickettii, Thermononospora curvata, and Azoarcus sp.KH33C. Meanwhile, cbbL-carrying bacterial composition was obviously influenced by soil bulk density, rhizosphere soil dissolved organic C, soil organic C, and microbial biomass C contents. Fertilizer practices were the principal factor influencing rhizosphere soil cbbL-carrying bacterial communities. These results showed that rhizosphere soil autotrophic bacterial communities were significantly changed under conditions of different long-term fertilization practices Therefore, increasing rhizosphere soil autotrophic bacteria community with crop residue and organic manure practices was found to be beneficial for management of double rice ecosystems in southern China.

• Korean Journal of Soil Science and Fertilizer
• /
• 제49권6호
• /
• pp.819-825
• /
• 2016

Monitoring of soil fertility and crop productivity in long-term application of silicate fertilizers is necessary to use fertilizers efficiently. This study was conducted to investigate effects of continuous application of silicate fertilizer for rice cultivation from 1969 to 2014. The treatments were no silicate fertilizer treatments (N, NC, NPK, and NPKC) and silicate fertilizer treatments (N+S, NC+S, NPK+S, and NPKC+S). The 46-yr input of $2\;ton\;ha^{-1}yr^{-1}$ of silicate fertilizer increased pH 0.6 ~ 1.1 and exchangeable Ca $2.0{\sim}2.4cmol_c\;kg^{-1}$ in silicate fertilizer treatments (N+S, NC+S, NPK+S, and NPKC+S) compared with no silicate fertilizer treatments (N, NC, NPK, and NPKC) because silicate fertilizer included Ca component. Also, available silicate concentrations of silicate fertilizer treatments (N+S, NC+S, NPK+S, and NPKC+S) increased $169mg\;kg^{-1}$ compared to no silicate fertilizer treatments. In Period II ('90~'14), the mean annual Si field balance varied from 62 to $175kg\;ha^{-1}yr^{-1}$ in silicate fertilizer treatments, indicating continuous accumulation of soil Si. Silicon uptake and grain yield of rice had greater differences between N treatment and N+S treatment than other treatments. This showed that the application of silicate fertilizer had greater effect in nutrient-poor soils than in proper nutrient soils. Thus the application of silicate fertilizer led to improvement the fertility of soil and increasement of rice production for the lack of soil nutrients.

• Korean Journal of Soil Science and Fertilizer
• /
• 제44권4호
• /
• pp.551-558
• /
• 2011

The aim of this study was to know whether leaf nitrate can be a substitute of total leaf N to justify plant N status and how nitrate influences macro elements uptake and physiological parameters of tomato plants under different nitrogen levels. Leaf nitrate content decreased in low N, while showed similar value with the control in high N, ranging from 55 to $70mg\;g^{-1}$. Differences in nitrate supply led to nitrate-dependent increases in macro elements, particularly cations, while gradual decrease in P. Physiological parameters, photosynthesis rates and antioxidants, greatly responded in N deficient conditions rather than high N, which didn't show any significant differences compared the control. Considering nitrogen forms and physiological parameters, total-N in tomato plants represented positive relation with growth (shoot dry weight), nitrate and $CO_2$ assimilation, whereas negative relation with lipid peroxidation.

• Korean Journal of Soil Science and Fertilizer
• /
• 제50권2호
• /
• pp.100-105
• /
• 2017

Various methods for assessing soil total nitrogen (TN) and inorganic N content have been developed to manage nutrient and to understand N cycle in soil. This paper address the technical procedures in arable soil samples to conduct soil sampling, sample preparation, and measuring total N and inorganic N. Among various methods for measuring soil total nitrogen contents, Kjeldahl distillation and Indophenol blue method have widely used due to reliability and economic advances. Also, two methods can analyze more samples at the same time compared with other nitrogen measuring methods. For evaluating inorganic N content, mainly in forms of nitrate-N ($NO_3{^-}-N$) and ammonium-N ($NH_4{^+}-N$), extraction with a single reagent such as 2M KCl has been employed, followed by Kjeldahl distillation or indophenol blue methods.

• Korean Journal of Soil Science and Fertilizer
• /
• 제47권3호
• /
• pp.205-212
• /
• 2014

Chronological changes of soil organic carbon (SOC) must be prepared by IPCC guidelines for national greenhouse gas inventories. IPCC suggested default reference SOC stocks for mineral soils and relative stock factors for different management activities where country own factors were not prepared. 3.4 million data were downloaded from agricultural soil information system and analyzed to get chronological changes of SOC for some counties and for land use in Korea. SOC content of orchard soil was higher than the other soils but chronological SOC changes of all land use had no tendency in differences with high standard deviation. SOC contents of counties depended on their own management activities and chronological SOC changes of districts also had no tendency in differences. Thus, Korea should survey the official records and relative stock factors on management activities such as land use, tillage and input of organic matter to calculate SOC stocks correctly. Otherwise, Korea should establish a model for predicting SOC by analyzing selected representative fields and by calculating SOC differences from comparing management activities of lands with those of representative fields.

• Korean Journal of Soil Science and Fertilizer
• /
• 제48권1호
• /
• pp.30-35
• /
• 2015

This study was conducted to investigate investigated the effect of nitrogen fertilizer on nitrate concentration in soil solution and to determine the relationship between yield and nitrate concentration in soil solution for cucumber cultivation under plastic film house. Nitrogen as urea was applied at rates of 0, 120, 240, 360, and $480kg\;N\;ha^{-1}$ as an additional fertilizer by trickle irrigation during cucumber cultivation. Monitoring of nitrate concentration in soil solution was investigated using porous cups at 25 cm depth under soil surface. Nitrate concentration in soil solution increased with increasing the rate of additional nitrogen. Correlation coefficient between EC value and nitrate concentration was positive in soil and soil solution (p<0.05). An additional nitrogen of about $300kg\;ha^{-1}$ was shown the highest yield of cucumber, and improved yield by 5% compared to N recommendation of $240kg\;N\;ha^{-1}$. The highest yield was determined at nitrate concentration of $82mg\;L^{-1}$ in soil solution by regression equation ($Y=74.2+0.73X+0.000504X^2$, $R^2=0.629^*$). These results means indicate that nitrate concentration in soil solution would be useful method to rapid determination for additional nitrogen during cucumber cultivation under plastic film house.

• Korean Journal of Soil Science and Fertilizer
• /
• 제46권3호
• /
• pp.216-222
• /
• 2013

Fertilizer management has the potential to promote the storage of carbon and nitrogen in agricultural soils and thus may contribute to crop sustainability and mitigation of global warming. In this study, the effects of fertilizer practices [no fertilizer (Control), chemical fertilizer (NPK), Compost, and chemical fertilizer plus compost] on soil total carbon (TC) and total nitrogen (TN) contents in inner soil profiles of paddy soil at 0-60 cm depth were examined by using long-term field experimental site at $42^{nd}$ years after installation. TC and TN concentrations of the treatments which included N input (NPK, Compost, NPK+Compost) in plow layer (0-15 cm) ranged from 19.0 to 26.4 g $kg^{-1}$ and 2.15 to 2.53 g $kg^{-1}$, respectively. Compared with control treatment, SOC (soil organic C) and TN concentrations were increased by 24.1 and 31.0%, 57.6 and 49.7%, and 72.2 and 54.5% for NPK, Compost, and NPK+Compost, respectively. However, long term fertilization significantly influenced TC concentration and pools to 30 cm depth. TC and TN pools for NPK, Compost, NPK+Compost in 0-30 cm depth ranged from 44.8 to 56.8 Mg $ha^{-1}$ and 5.78 to 6.49 Mg $ha^{-1}$, respectively. TC and TN pools were greater by 10.5 and 21.4%, 30.3 and 29.6%, and 39.9 and 36.3% in N input treatments (NPK, Compost, NPK+Compost) than in control treatment. These resulted from the formation and stability of aggregate in paddy soil with continuous mono rice cultivation. Therefore, fertilization practice could contribute to the storage of C and N in paddy soil, especially, organic amendments with chemical fertilizers may be alternative practices to sequester carbon and nitrogen in agricultural soil.

• Korean Journal of Soil Science and Fertilizer
• /
• 제47권2호
• /
• pp.120-126
• /
• 2014

An accurate analysis of nutrient balance in different cropping systems is necessary for improving soil fertilities, causing higher crop yields and quality. This study was carried out to investigate the nutrient balance, changes in soil properties, and their effects on crop yield in long-term field cultivation under mono- and rotation-cropping systems (MCS and RCS, respectively). The analytical results of the soil properties showed that the application of mineral fertilizers alone in the MCS leads the reduction of soil CEC, exchangeable Ca, and microbial biomass C and N. Compared with the MCS of soybean, the RCS of soybean and barley significantly improved the soil properties, which increased crop yield. It might be due to the barley residue added to the RCS soil. Mean nutrient balances for 4 years were -55.9 kg N, +34.7 kg $P_2O_5$, and -0.3 kg $K_2O$ $ha^{-1}$ for the MCS and +19.7 kg N, +107.4 kg $P_2O_5$, and -48.6 kg $K_2O$ $ha^{-1}$ for the RCS, respectively. These nutrient imbalances mean that conventional fertilizer recommendations were inadequate for maintaining soil nutrient balance. From these results, we can conclude that the crop rotation may change comprehensive physical, chemical, and biological soil properties. These changes could affect the nutrient balance and then the crop yield.

• Korean Journal of Soil Science and Fertilizer
• /
• 제47권6호
• /
• pp.594-597
• /
• 2014

Crop yields depend on the limiting factor of crop growth; Liebig law of minimum. Identifying the kind and the necessary amount of the limiting factor is essential to increase crop yield. Although nitrogen is the most essential nutrient, N application does not always bring about yield increases when other elements are limiting in rice cultivation. Two experiments were compared to elucidate the effect of soil testing on rice yield response to N level. The one was an experiment about yield response of 3 rice cultivars to 7 levels of N application, which was conducted from 2003 to 2004 in 25 farmer's fields without ameliorating soil conditions by soil testing and the other was a demonstration experiment on N fertilizer recommendation equation by 0, 0.5, 1.0, and 1.5 times of N recommended level in 5 soil types from 30 fields after ameliorating soil conditions by soil testing. The N response patterns of the experiments conducted without soil testing showed a Mitscherlich pattern in some cultivars and soil types, but did not in the others. The N response patterns of the demonstration experiment showed a Mitscherlich pattern in all soil types. Because these results indicated that N was the minimum nutrient in the demonstration experiment by ameliorating soil conditions with soil testing, but not in the other experiment without soil testing, the supply of minimum nutrients by soil testing could increase the efficiency of N-fertilization.

• Korean Journal of Soil Science and Fertilizer
• /
• 제46권3호
• /
• pp.223-229
• /
• 2013

Sustainability index was calculated to determine the best management for rice productivity under long-term inorganic fertilizer management's practices. It is based on nutrient index, microbiological index and crop index related to sustainability as soil function. Indicators for calculating sustainability index were selected by the comparison of soil properties and rice response in paddy soil with fertilization. Total twenty two indicators were determined to assess nutrient index, microbiological index and crop index in order to compare the effect of different fertilization. The indices were applied to assess the sustainability with different inorganic fertilizer treatments such as control, N, NK, NP, NPK, NPK+Si, and NPK+Compost. The long-term application of compost with NPK was the highest sustainability index value because it increased nutrient index, microbial index and crop index. The use of chemical fertilizers resulted in poor soil microbial index and crop index, but the treatments like NP, NPK, and NPK+Si were maintained sustainability in paddy soil. These results indicate that application of organic and chemical fertilizer could be a good management to improve rice sustainability in paddy soil.