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Rice Husk Biochar Influences Seedling Emergence of Junglerice (Echinochloa colona) and Herbicide Efficacy  [PDF]
Bhagirath S. Chauhan
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.47164
Abstract:

The use of carbonized rice husk biochar improves the fertility and productivity of poor soils in rice-based cropping systems. However, biochar may also influence weed seedling emergence and the efficacy of soil-applied herbicides. Experiments were conducted in a screenhouse to evaluate the effect of biochar rates (0, 20, 40, and 80 t·ha?1) and seed burial depth (0, 1, and 2 cm) on seedling emergence of junglerice (Echinochloa colona) and the effect of biochar rates and pendimethalin (0, 500, 1000, and 1500 g·a.i.·ha?1) and pretilachlor doses (0, 300, 600, and 900 g·a.i.·ha?1) on seedling emergence and seedling biomass of junglerice. Data were analyzed using nonlinear regression. The burial depth to inhibit 50% of maximum seedling emergence was 0.76 cm when biochar was not added to soil and the depth increased with an increase in biochar rates for soil. Similarly, compared with the soil with no biochar, the use of bichoar increased the pretilachlor dose to inhibit 50% of maximum emergence or biomass. The pretilachlor dose to inhibit 50% of maximum biomass of junglerice was 100, 130, 240, and

Invasive Species Echinochloa colona Reduces Abundance and Diversity of Resident Plant Communities in Tropical Wetland  [PDF]
Samora M. Andrew
Open Journal of Ecology (OJE) , 2018, DOI: 10.4236/oje.2018.89029
Abstract:
Although the relationship between invasive alien species (IAS) and plant community structure has attracted considerable interest, the impacts of IAS on abundance and diversity of resident plant communities in species rich-ecosystems, such as tropical wetlands are poorly understood. Consequently, this has impeded development of improved management strategies and successful restoration of invaded tropical wetlands. Therefore, data on vegetation were collected from 60 plots of 20 × 50 m to study the impacts of alien invasive grass Echinochloa colona (L.) Link abundance on plant community abundance, richness, evenness and diversity of resident plant species within grasslands of the Kilombero Valley wetland, Tanzania. Moreover, the impacts of abundance of E. colona on plant functional groups (i.e. graminoids, forbs and shrubs) richness were also explored. Generalized linear models showed that community richness, evenness, diversity and abundance of resident species were negatively related to the E. colona abundance. There was a negative relationship between richness of graminoids and shrubs and the abundance of E. colona. Similarly, the abundance of graminoids, forbs and shrubs is related negatively to the abundance of E. colona. Given that most of the community and functional group attributes of resident plants is related negatively to E.
Allelopathic Activity of Crop Residue Incorporation Alone or Mixed Against Rice and its Associated Grass Weed Jungle Rice (Echinochloa colona [L.] Link)
Khaliq,Abdul; Matloob,Amar; Ata Cheema,Zahid; Farooq,Muhammad;
Chilean journal of agricultural research , 2011, DOI: 10.4067/S0718-58392011000300012
Abstract: weed suppression is one of the several benefits achieved by soil incorporation of crop residues and such suppression is believed to be allelopathic in nature. the allelopathic potential of different crop residues: viz. sorghum (sorghum bicolor [l.] moench), sunflower (helianthus annuus l.), brassica (brassica campestris l.) was evaluated in rice (oryza sativa l.) and jungle rice (echinochloa colona [l.] link). chopped crop residues were soil-incorporated alone and mixed at 6 g kg-1 soil (12 t ha-1) and compared with a control without residues. soil incorporation of residues substantially delayed germination of jungle rice. the time to start germination, time to 50% emergence, mean emergence time, emergence index, and final germination percentage were all depressed by residue incorporation. final germination of rice and jungle rice dropped by 11 to 15% and 11 to 27% with residue application alone and by 18 to 22% and 8 to 34% with a combination of crop residues, respectively. residues were more suppressive to germination dynamics of jungle rice than rice. crop residues exerted a pronounced negative influence on the shoot (25 to 100% and 14 to 44%) and root lengths (22 to 100% and 10 to 43%) of rice and jungle rice, respectively. shoot and root dry weight of both rice and jungle rice also decreased significantly. an appreciable quantity of phenolics was recorded in soil amended with sorghum+sunflower+brassica residues. since soil incorporation of allelopathic crop residues was detrimental to both rice germination and seedling growth, it is suggested that the time of residue application for jungle rice suppression and rice seeding time need to be adjusted so as to minimize rice crop damage.
Rice Husk Biochar for Rice Based Cropping System in Acid Soil 1. The Characteristics of Rice Husk Biochar and Its Influence on the Properties of Acid Sulfate Soils and Rice Growth in West Kalimantan, Indonesia  [cached]
Agusalim Masulili,Wani Hadi Utomo,Syechfani MS
Journal of Agricultural Science , 2010, DOI: 10.5539/jas.v2n1p39
Abstract: The experiments were carried out to study the characteristics of biochar made from rice husk and its potential as a soil amendment in acid soils. Biochar was produced by pyrolysis; after which it was applied as a soil amendment. The soil was incubated for 30 days, and then it was planted with rice. For comparison, soil was applied with: rice straw, rice husk, rice husk ash, Chromolaena odorata biomass, and no soil amendment. The characteristics of biochar were: water content 4.96%, pH 8.70, C 18.72%, P 0.12%, CEC 17.57cmol kg-1, K 0.20%, Ca 0.41%, Mg 0.62%, and Na 1.40%. Application of biochar decreased soil bulk density, soil strength, exchangeable Al, and soluble Fe and increased porosity, available soil water content, C-organic, soil pH, available P, CEC, exchangeable K, and Ca. Out of these improvements, only soil carbon, phosphorus, exchangeable Al, soluble Fe, and soil strength significantly influenced rice biomass.
Allelopathic Activity of Crop Residue Incorporation Alone or Mixed Against Rice and its Associated Grass Weed Jungle Rice (Echinochloa colona [L.] Link) Actividad Alelopática de Residuos de Cultivo Incorporados Solos o en mezcla contra arroz y su maleza asociada pasto del arroz o pasto Shama (Echinochloa colona [L.] Link)  [cached]
Abdul Khaliq,Amar Matloob,Zahid Ata Cheema,Muhammad Farooq
Chilean Journal of Agricultural Research , 2011,
Abstract: Weed suppression is one of the several benefits achieved by soil incorporation of crop residues and such suppression is believed to be allelopathic in nature. The allelopathic potential of different crop residues: viz. sorghum (Sorghum bicolor [L.] Moench), sunflower (Helianthus annuus L.), brassica (Brassica campestris L.) was evaluated in rice (Oryza sativa L.) and jungle rice (Echinochloa colona [L.] Link). Chopped crop residues were soil-incorporated alone and mixed at 6 g kg-1 soil (12 t ha-1) and compared with a control without residues. Soil incorporation of residues substantially delayed germination of jungle rice. The time to start germination, time to 50% emergence, mean emergence time, emergence index, and final germination percentage were all depressed by residue incorporation. Final germination of rice and jungle rice dropped by 11 to 15% and 11 to 27% with residue application alone and by 18 to 22% and 8 to 34% with a combination of crop residues, respectively. Residues were more suppressive to germination dynamics of jungle rice than rice. Crop residues exerted a pronounced negative influence on the shoot (25 to 100% and 14 to 44%) and root lengths (22 to 100% and 10 to 43%) of rice and jungle rice, respectively. Shoot and root dry weight of both rice and jungle rice also decreased significantly. An appreciable quantity of phenolics was recorded in soil amended with sorghum+sunflower+brassica residues. Since soil incorporation of allelopathic crop residues was detrimental to both rice germination and seedling growth, it is suggested that the time of residue application for jungle rice suppression and rice seeding time need to be adjusted so as to minimize rice crop damage. La represión de malezas es uno de los beneficios logrados por la incorporación de residuos de cosecha al suelo y se cree que es de naturaleza alelopática. Se evaluó el potencial alelopático de diversos residuos de cultivos: sorgo (Sorghum bicolor [L.] Moench), girasol (Helianthus annuus L.) y coles (Brassica Compestris L.) en arroz (Oryza sativa L.) y pasto arroz o pasto Shama (Echinochloa colona [L.] Link). Los residuos de cosecha picados se incorporaron solos y en mezcla a 6 g kg-1 de suelo (12 t ha-1) y se compararon con un testigo sin residuos. La incorporación de los residuos al suelo retrasó sustancialmente la germinación del pasto arroz o pasto Shama. El tiempo para empezar la germinación, el tiempo a 50% de emergencia, el tiempo medio de emergencia, el índice de emergencia, y el porcentaje de germinación final fueron influidos negativamente por la incorporación d
稻壳/高密度聚乙烯复合材料与稻壳炭/高密度聚乙烯复合材料性能对比
Comparison of properties between rice husk/high density polyethylene and rice husk biochar/high density polyethylene composites
 [PDF]

张庆法,杨科研,蔡红珍,孔令帅,刘建彪,姜戌雅
- , 2018, DOI: 10.13801/j.cnki.fhclxb.20180227.002
Abstract: 采用挤出法制备稻壳/高密度聚乙烯(HDPE)和稻壳炭/HDPE复合材料。利用SEM、XRD对稻壳/HDPE和稻壳炭/HDPE复合材料进行表征,并对其力学性能和抗蠕变性能进行测试对比。结果表明,稻壳和HDPE之间的结合方式与稻壳炭和HDPE之间的结合方式存在根本性的差异,稻壳/HDPE复合材料表现为稻壳被HDPE所包裹,稻壳炭/HDPE复合材料表现为HDPE嵌入稻壳炭的孔隙中;稻壳和稻壳炭的加入都会影响HDPE基复合材料的结晶峰强度,但不会对其微晶结构产生影响;无论是抗弯强度、拉伸强度还是抗蠕变强度,稻壳炭/HDPE复合材料都远远强于稻壳/HDPE复合材料。 The extrusion method was applied to prepare rice husk/high density polyethylene (HDPE) and rice husk biochar/HDPE composites. The morphological properties of the rice husk/HDPE and rice husk biochar/HDPE composites were evaluated by SEM and XRD analysis, the mechanical properties and creep resistance of composites were also observed and compared. The results show that the combination of rice husk/HDPE composites is so different from rice husk biochar/HDPE composites:rice husk/HDPE composites show that the husk is covered by HDPE, rice husk biochar/HDPE composites show HDPE is embedded in the pores of rice husk biochar; The XRD shows that both rice husk and rice husk biocar can affect the intensity of the peaks of the composites but have little effect on the crystallite structure; And whether it is bending, tensile or creep resistance, rice husk biochar/HDPE composites are much stronger than those of rice husk/HDPE composites. 2016年山东省重点研发计划(重大关键技术)(2016ZDJS11A01);山东省泰山学者特聘专家;山东省高等学校优势学科人才团队培育计划
The Impact of Biochar Application on Soil Properties and Plant Growth of Pot Grown Lettuce (Lactuca sativa) and Cabbage (Brassica chinensis)  [PDF]
Sarah Carter,Simon Shackley,Saran Sohi,Tan Boun Suy,Stephan Haefele
Agronomy , 2013, DOI: 10.3390/agronomy3020404
Abstract: The effect of rice-husk char (potentially biochar) application on the growth of transplanted lettuce ( Lactuca sativa) and Chinese cabbage ( Brassica chinensis) was assessed in a pot experiment over a three crop (lettuce-cabbage-lettuce) cycle in Cambodia. The biochar was the by-product of a rice-husk gasification unit and consisted of 28.7% carbon (C) by mass. Biochar application rates to potting medium of 25, 50 and 150 g kg ?1 were used with and without locally available fertilizers (a mixture of compost, liquid compost and lake sediment). The rice-husk biochar used was slightly alkaline (pH 7.79), increased the pH of the soil, and contained elevated levels of some trace metals and exchangeable cations (K, Ca and Mg) in comparison to the soil. The biochar treatments were found to increase the final biomass, root biomass, plant height and number of leaves in all the cropping cycles in comparison to no biochar treatments. The greatest biomass increase due to biochar additions (903%) was found in the soils without fertilization, rather than fertilized soils (483% with the same biochar application as in the “without fertilization” case). Over the cropping cycles the impact was reduced; a 363% increase in biomass was observed in the third lettuce cycle.
Allelopathy of Rice Husk on Barnyardgrass  [PDF]
Jonghan Ko,Seok Hyun Eom,Myong Jo Kim,Chang Yeon Yu
Journal of Agronomy , 2005,
Abstract: Research efforts in seeking allelopathic compounds play an important role in developing natural herbicides. The objective of this research was to investigate the allelopathic effects of rice (Oryza sativa L.) husk extracts and to bioassay allelopathic compounds. The husk extracts of seven rice varieties were used to examine allelopathic effects on the growth of barnyardgrass (Echinochloa crusgalli (L.) Beauv.). After that, allelopathic substances effective on the growth of barnyardgrass were sought using an open chromatography and analyzed using a GC/MS. Husk extract from Ilpum rice (a national variety in South Korea) showed the prominent allelopathic effect on barnyardgrass. The organic compounds analyzed by the GC/MS were found to be 9-octadecenoic acid; 7-octadecenoic acid; 5, 8, 11-heptadecatriynoic acid and androstan-17-one. The minimum inhibition concentration of the isolated allelochemical compounds was 50 ppm. The results suggest that there is a possibility of developing a rice husk oriented natural herbicide effective on barnyardgrass.
The Different Expressions of Draft Cherry Tomato Growth, Yield, Quality under Bamboo and Rice Husk Biochars Application to Clay Loamy Soil  [PDF]
Tran Thi Thu Hien, Yoshiyuki Shinogi, Tomoyuki Taniguchi
Agricultural Sciences (AS) , 2017, DOI: 10.4236/as.2017.89068
Abstract: This study evaluated the different expressions of cherry tomato growth, yield and quality under bamboo and rice husk biochar applications to soil. The experiment was conducted under glasshouse conditions at Hakozaki campus, Kyushu University, Japan and consisted of 5 treatments, namely 1) no biochar application as a control; 2) 2% (RH2) and 3) 5% (RH5) of rice husk biochar; 4) 2% (BB2) and 5) 5% (BB5) of bamboo biochar. Bamboo biochar application significantly improved tomato growth, including number of leaves, fresh biomass yield of aboveground and underground parts for BB5; number of fruit; fresh yield from 24% - 25% for BB2 and BB5. In particular, both bamboo and rice husk biochar application at two rates 2% and 5% had positive effects on tomato quality, demonstrated by the increased total sugar content from 56% to 91%, and the enhancement of ascorbic acid content for BB2 and RH2 by 12% and 17%, respectively. Those improvements reflected the soil physiochemical property changes after biochar application, including the increase in plant available water for bamboo biochar amendment before and after cultivating by 25% - 38% and 9% - 18%, respectively, compared with those of control; and the increased total soil N for bamboo biochar treatments (11% - 14%). Generally, all data above support bamboo biochar utilization for the purpose of improving soil properties and developing crop production.
Controle de Capim-Arroz (Echinochloa spp.) em fun??o de métodos de manejo na cultura do arroz irrigado
Pinto, J.J.O.;Galon, L.;DAL Magro, T.;Procópio, S.O.;Concen?o, G.;Pinho, C.F.;Ferreira, E.A.;
Planta Daninha , 2008, DOI: 10.1590/S0100-83582008000400008
Abstract: the objective of this work was to evaluate the efficiency of the herbicide penoxsulam as a function of the start of permanent irrigation and time and rate of application, in controlling echinochloa crusgalli and e. colona, as well as its selectivity to the rice culture, cv. qualimax 1. the trial was conducted under field conditions in a completely randomized block design, in a factorial scheme 2x3x4 with four replications. the factorial scheme were the irrigation starting times (21 and 30 days after emergence - dae), application times (pre-emergence and early and late post-emergence) and penoxsulam rates (0, 18, 36 and 72 g h 1). the evaluated variables were echinochloa control, rice plant phytotocixity, and rice grain yield. early irrigation increased the efficiency of penoxsulam in echinochloa control; however, the effect of late irrigation was partially offset by the increase in the penoxsulam rates. when irrigation started late, reduced grain yield was observed independently time and rate of herbicide application.
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