Application of Microbial Fertilizers in Sustainable Agriculture

Summary

This paper summarizes the conception and development of microbial fertilizers and inoculants in China that are used to improve soil quality and the growth, yield and protection of crops. The results presented show the relative effects of these microbial products applied singly or with chemical fertilizers on soil fertility, crop yield and protection. The paper discusses current trends in the development and use of microbial fertilizers in China and suggests areas of high priority research.     

Measure and Analysis on the Temperature Field of Sodium Silicate Bonded Sand Heating by Microwave Energy

The temperature field of sodium silicate bonded sand heating by microwave energy is measured and analyzed by the related characteristic quentities. The result shows that sodium silicate bonded sand heating by microwave energy has characters such as temperature rising speedy and heating occurring from inside to outside at the same time. The reasons of those characters are discussed by testing and analyzing. The viewpoint that the temperature rising of sodium silicate bonded sand heating by microwave energy is revocable by sodium silicate absorbing microwave energy is proposed. The results of this study are useful on rightly understanding the essentials of the heating by microwave energy for sodium silicate sand and rightly constituting heating technology.     

Coal Fly Ash and Phospho‐gypsum Mixture as an Amendment to Improve Rice Paddy Soil Fertility

Abstract

Rice is a plant that requires high levels of silica (Si). As a silicate (SiO₂) source to rice, coal fly ash (hereafter, fly ash), which has an alkaline pH and high available silicate and boron (B) contents, was mixed with phosphor‐gypsum (hereafter, gypsum, 50%, wt wt^?1), a by‐product from the production of phosphate fertilizer, to improve the fly ash limitation. Field experiments were carried out to evaluate the effect of the mixture on soil properties and rice (Oryza sativa) productivity in silt loam (SiL) and loamy sand (LS) soils to which 0 (FG 0), 20 (FG 20), 40 (FG 40), and 60 (FG 60) Mg ha^?1 were added. The mixture increased the amount of available silicate and exchangeable calcium (Ca) contents in the soils and the uptake of silicate by rice plant. The mixture did not result in accumulation of heavy metals in soil and an excessive uptake of heavy metals by the rice grain. The available boron content in soil increased with the mixture application levels up to 1.42 mg kg^?1 following the application of 60 Mg ha^?1 but did not show toxicity. The mixture increased significantly rice yield and showed the highest yields following the addition of 30–40 Mg ha^?1 in two soils. It is concluded that the fly ash and gypsum mixture could be a good source of inorganic soil amendments to restore the soil nutrient balance in rice paddy soil.     

Macronutrients in Marandu Palisade Grass as Influenced by Lime,Slag, and Nitrogen Fertilization

Soil acidity is one of the main limiting factors for the growth of pasture grasses in Brazilian soils. In addition to lime, slag can be used to correct soil acidity and help plants to absorb nutrients in adequate amounts. The objective of this experiment was to evaluate, under greenhouse conditions, the effects of slag and lime plus nitrogen (N) on marandu palisade grass plants' nutritional status as well as the absorption of macronutrients submitted to two cuts. The treatments consisted of two corrective materials (slag and lime), three corrective material rates (0.81, 1.61, and 3.22 g dm^?3 of ECaCO₃), three N rates (75, 150, and 300 mg dm^?3) plus a control treatment, with four replications. Macronutrient contents in the forage plants were found to be present in adequate levels. The mean value of N accumulated in the shoot was 40.1 mg per plant, phosphorus (P) was 4.6 mg per plant, potassium (K) was 38.6 mg per plant, calcium (Ca) was 7.3 mg per plant, magnesium (Mg) was 6.7 mg per plant, and sulfur (S) was 3.5 mg per plant at the first cut. At the second cut, the nutrient accumulations values were N 50.8 mg per plant, P 6.3 mg per plant, K 20.7 mg per plant, Ca 21.6 mg per plant, Mg 24.0 mg per plant, and S 4.7 mg per plant. Macronutrients accumulation in the shoot of grass increased with the addition of both the correctives as well as the N rates.     

Response of Sugarcane to Calcium Silicate on Yield,Gas Exchange Characteristics,Leaf Nutrient Concentrations,and Soil Properties in Two Different Soils

Silicon (Si), applied as calcium silicate (Ca-silicate), was evaluated for effects on yield; yield-contributing parameters in sugarcane, such as chlorophyll content, gas exchange characteristics, moisture content, and leaf nutrient concentrations; and soil fertility in the greenhouse in two different soil types. Seven levels of Si (0 20, 40, 60, 80, 120, and 150 g pot^–1) were tested by applying them with traditional fertilizers. Gas exchange characteristics such as photosynthesis, transpiration, and stomatal conductance were significantly greater with the plants fertilized with silicate over unamended control for both soils. Silicate fertilization increased chlorophyll and moisture contents in the top visible dewlap (TVD) leaf tissues, but results were not significantly better in both soils when compared with unamended control. In our 12-month study, we found that the Si content reached up to 2.64% and 1.86% per dry mass in TVD leaf tissues when amended with Ca-silicate fertilizer in soils 1 and 2, respectively. Results showed that as compared to unamended control, Si-amended treatments significantly increased maximum dry matter and cane yield by 77% and 66% in soil 1 and 41% and 15% in soil 2, respectively. With increasing silicate application, iron, copper, zinc, and manganese contents significantly decreased in leaf tissues and soil contents in both soils. Soil pH, Si contents, available sulfur, exchangeable Ca and magnesium, and cation exchange capacity were increased significantly more or less, whereas aluminum contents of soil decreased dramatically in both soils when amended with Ca-silicate. Our results indicate that different soil fertility status and rates of Si application are important factors influencing the yield, growth parameters, chlorophyll, and nutrient contents of sugarcane leaf as well as soil properties.     

硅酸钾与密旋链霉菌Act12菌剂配施对连作草莓生长、果实产量及品质的影响

为了探索硅酸钾与生防放线菌配合施用对草莓连作障碍的修复效果,以"红太后"草莓为材料,采用日光温室栽培,研究了硅酸钾与密旋链霉菌Act12菌剂配施对连作草莓生长、果实产量及品质的影响。结果表明:(1)硅酸钾与密旋链霉菌Act12菌剂配施对日光温室连作草莓具有明显的防病促生作用,可使连作3年草莓1级苗比例提高44.7%,3级苗比例下降58.3%,连作4年草莓死亡率降至0%;连作3年草莓植株总鲜重、根鲜重、叶片数及叶片鲜重分别增加73.7%、71.3%、11.1%及38.7%。(2)硅酸钾与密旋链霉菌Act12菌剂配施对草莓开花、果实产量及品质有明显影响,可使连作3年草莓开花提前10 d,花蕾数提高17.0%,果实数、单果鲜重及单株产量分别增加18.6%、90.6%及126.2%,盛果期草莓果实可溶性固形物含量、糖酸比及维生素C含量分别提高21.7%、36.2%及27.0%;可显著提高连作4年草莓单果鲜重和单株产量(P<0.05),增幅分别为194.7%和359.1%。(3)硅酸钾与密旋链霉菌Act12菌剂配施可提高草莓的诱导抗性,草莓叶片可溶性蛋白含量和盛果期PPO酶活性分别提高67.4%和101.0%。由此可知,硅酸钾与密旋链霉菌Act12菌剂配施可显著促进连作草莓生长,提高果实产量及品质,增强植株抗病性,可有效缓解日光温室草莓连作障碍,在生产上具有较好应用潜力。     

Evaluation of Decomposition Procedure to Determine Ba,Co, Cr,Cu, Ni,Mn, V,and Zn Total Content in Soil Samples

Different procedures have been proposed to decompose soil samples. Most of them regard determination with fertility aims. In this case, the contents available to the plants are considered. On the other hand, there are procedures to determine total content. The objective of this work was to propose a new decomposition procedure to determine barium (Ba), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), vanadium (V), and zinc (Zn) total content in tropical soils with high content of oxides and silicate. According to the results, the digestion procedure proposed in this study provided satisfactory results for the contents recovery for the elements Ba, Co, Cr, Cu, Mn, Ni, V, and Zn, above 90%, and the use of inverted aqua regia, hydrogen peroxide (H₂O₂), hydrofluoric acid (HF), pre-digestions and agitation was shown as a new alternative for the high silicate content soil sample total digestion, such as the oxisols.     

不同来源硅酸盐菌剂质量分析研究

对３种硅酸盐菌剂进行了菌群组成、含菌量及生物学活性的测定,作出了评价,提出了改良菌剂品质的建议     

Effect of calcium silicate on nutrient use of lowland rice and greenhouse gas emission from a paddy soil under alternating wetting and drying

In intensively irrigated rice cultivation, plant-available silicon (Si) is a crucial nutrient for improving rice productivity. As a source of Si, calcium silicate (CaSiO₃) was amended to evaluate the effect of silicate fertilizer on rice production, nitrogen (N) use efficiency, and greenhouse gas (GHG) emission under alternating wetting and drying in a pot experiment using a tropical soil from a paddy field of the International Rice Research Institute (IRRI) in the Philippines. Four levels of CaSiO₃ amendment, 0, 112.7, 224.5, and 445.8 kg ha^-1, with the recommended N rate were tested. The results showed that although CaSiO₃ amendment of 112.7 kg ha^-1 resulted in higher rice straw, improved N use efficiency, and reduced N₂O emission, there was no difference in grain yield among the four levels of CaSiO₃ amendment owing to relatively lower harvest index. Moreover, CaSiO₃ amendment showed a reverse trend between CH₄ and N₂O emissions as it reduced N₂O emission while led to significantly increased CH₄ emission and global warming potential. Thus, CaSiO₃ amendment was a possible alternative to improve N use efficiency and increase rice straw biomass, but it needs to be reviewed in line with grain yield production and GHG emission. It is also imperative to test an optimal method of silicate fertilizer amendment in future research in order to compromise a negative impact in tropical soils.     

喷施钙硅对设施春茬番茄根系生长、NPK吸收及产量和水分利用的影响

以番茄品种鑫语为试验材料,在开花盛果期喷施含Ca(NO_3)_2、Ca(H_2PO_4)_2、KSiO_4、Ca(NO_3)_2+KSiO_4及Ca(H_2PO_4)_2+KSiO_4的悬液,探讨钙硅单一及配合施用对设施春茬番茄根系生长、NPK吸收、产量及水分利用率的影响。结果表明:喷施钙硅悬液显著促进番茄根系生长及发育,显著促进根系和果实磷钾吸收;含钙悬液单独喷施处理的根系和果实氮吸收显著高于硅悬液及钙硅复配悬液;两种含钙悬液Ca(NO_3)_2和Ca(H_2PO_4)_2喷施处理取得最佳调控效果,与对照相比,分别使番茄增产9%和7%,水分利用率提升7、5.5 kg·m~(-3),喷施Ca(NO_3)_2+KSiO_4使番茄增产4.7%,水分利用率提升3.8 kg·m~(-3),喷施Ca(H_2PO_4)_2+KSiO_4和KSiO_4未取得显著的调控效果;含钙悬液单独喷施处理增加番茄产量与其促进根系发育及增加植株N吸收密切相关;两种含钙物质与KSiO_4对番茄产量的影响存在显著的交互效应,对产量的贡献呈:含钙物质含钙物质×KSiO_4KSiO_4。含钙悬液喷施技术简单高效,能实现番茄增产及生物节水能力提升。