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The comfort level of human being can be increased by effective noise management without damaging the external environmental resources. The burning of rice stubble particularly in rice growing Asian countries makes the situation bad to worst. Rice stubble deserve for an immediate solution of in product development for its sustainable disposal. Rice stubble, cotton fly waste were used to manufacture composite material to be used as acoustic panel. Rice stubble powder 60%, 70%, and 80%, cotton fly waste 20%, 30%, and 40% by weight, and polyurethane (PU) resin were used to manufacture composite as acoustic panels. The composites were tested for pore size, morphology, water absorbability, and noise reduction coefficient (NRC) mainly. Acceptable level of NRC and other features were achieved. This study will provide a new pathway to use the discarded challenging waste materials to manufacture wealth-generating products. [ABSTRACT FROM AUTHOR]

Agronomic measures are the key to promote the sustainable development of ratoon rice by reducing the damage from mechanical crushing to the residual stubble of the main crop, thereby mitigating the impact on axillary bud sprouting and yield formation in ratoon rice. This study used widely recommended conventional rice Jiafuzhan and hybrid rice Yongyou 2640 as the test materials to conduct a four-factor block design field experiment in a greenhouse of the experimental farm of Fujian Agricultural and Forestry University, China from 2018 to 2019. The treatments included fertilization and no fertilization, alternate wetting and drying irrigation and continuous water flooding irrigation, and plots with and without artificial crushing damage on the rice stubble. At the same time, a 13C stable isotope in-situ detection technology was used to fertilize the pot experiment. The results showed significant interactions among varieties, water management, nitrogen application and stubble status. Relative to the long-term water flooding treatment, the treatment with sequential application of nitrogen fertilizer coupled with moderate field drought for root-vigor and tiller promotion before and after harvesting of the main crop, significantly improved the effective tillers from low position nodes. This in turn increased the effective panicles per plant and grains per panicle by reducing the influence of artificial crushing damage on rice stubble and achieving a high yield of the regenerated rice. Furthermore, the partitioning of 13C assimilates to the residual stubble and its axillary buds were significantly improved at the mature stage of the main crop, while the translocation rate to roots and rhizosphere soil was reduced at the later growth stage of ratooning season rice. This was triggered by the metabolism of hormones and polyamines at the stem base regulated by the interaction of water and fertilizer at this time. We therefore suggest that to achieve a high yield of ratoon rice with low stubble height under mechanized harvesting, the timely application of nitrogen fertilizer is fundamental, coupled with moderate field drying for root-vigor preservation and tiller promotion before and after the mechanical harvesting of the main crop.

Arable soils irrigated with wastewater (SIWs) cause ecological and human health issues due to the presence of heavy metals (HMs). Burning rice stubble (RS) poses severe environmental and human health hazards. Converting RS into rice stubble compost (RSC) and rice stubble biochar (RSB) can overcome these issues. Here, we considered the role of RS, RSC, and RSB as individual soil amendments and combined each of them with arbuscular mycorrhiza fungi (AMF) to observe their effectiveness for HM immobilization in SIW, their uptake in pea plants, and improvements in the physicochemical properties of soil. The results revealed that adding RSB and AMF reduced the bioavailable concentrations of Pb, Cd, Ni, Cu, Co, and Zn in SIW by 35%, 50%, 43%, 43%, 52%, and 22%, respectively. Moreover, RSB+AMF treatment also reduced Pb, Cd, Ni, Cu, Co, and Zn concentrations in grain by 93%, 76%, 83%, 72%, 71%, and 57%, respectively, compared to the control. Improvements in shoot dry weight (DW) (66%), root DW (48%), and grain yield (56%) per pot were also the highest with RSB+AMF. RSB+AMF treatment enhanced soil health and other soil attributes by improving the activity of urease, catalase, peroxidase, phosphatase, β-glucosidase, and fluorescein diacetate by 78%, 156%, 62%, 123%, 235%, and 96%, respectively. Interestingly, RSB+AMF also led to the strongest AMF–plant symbiosis, as assessed by improved AMF root colonization (162%), mycorrhizal intensity (100%), mycorrhizal frequency (104%), and arbuscular abundance (143%). To conclude, converting RS into RSB can control air pollution caused by RS burning. Moreover, adding RSB with AMF to SIW can reduce HM uptake in plants, improve soil health, and thus minimize ecological and human health issues. [ABSTRACT FROM AUTHOR]

ABSTRACT In the process of rice harvesting, the passability of the track combine harvester is often limited by the state of the soil. Meanwhile, wet and soft paddy soil is compacted under the rolling of harvesting machinery, which also affects the soil function and the ecological environment. Therefore, the relationship between the physical and mechanical properties of wet and soft paddy soil was studied in this paper. In addition, compaction from a track combine harvester on field soil with and without rice stubble was studied. The density and gradation of wet and soft paddy soil were positively correlated with cohesion and negatively correlated with the internal friction angle. In paddy soil with a moisture content of 16–36%, the soil moisture content was negatively correlated with cohesion and internal friction angle. Additionally, the plastic deformation of soil with rice stubble under compaction was greater than that without rice stubble, and the plastic deformation of the field with rice stubble mainly occurred in the second rolling stage. Increasing the speed of the track combine harvester effectively reduced the compaction risk of rice stubble soil.

Microbial degradation is an effective, eco-friendly and sustainable approach for management of the rice residue. After harvesting a rice crop, removal of stubble from the ground is a challenging task, that forces the farmers to burn the residue in-situ. Therefore, accelerated degradation using an eco-friendly alternative is a necessity. White rot fungi are the most explored group of microbes for accelerated degradation of lignin but they are very slow in growth. The present investigation focuses on degradation of rice stubble using a fungal consortium constructed with highly sporulating ascomycetes fungi, namely, Aspergillus terreus, Aspergillus fumigatus and Alternaria spp. All three species were successful at colonizing the rice stubble. Periodical HPLC analysis of rice stubble alkali extracts revealed that incubation with ligninolytic consortium released various lignin degradation products such as vanillin, vanillic acid, coniferyl alcohol, syringic acid and ferulic acid. The efficiency of the consortium was further studied at different dosages on paddy straw. Maximum lignin degradation was observed when the consortium was applied at 15% volume by weight of rice stubble. Maximum activity of different lignolytic enzymes such as lignin peroxidase, laccase and total phenols was also found with the same treatment. FTIR analysis also supported the observed results. Hence, the presently developed consortium for degrading rice stubble was found to be effective in both laboratory and field conditions. The developed consortium or its oxidative enzymes can be used alone or combined with other commercial cellulolytic consortia to manage the accumulating rice stubble effectively. [ABSTRACT FROM AUTHOR]

Rice stubble is an agricultural waste with 30.67% yield of cellulose (90.05% α-cellulose content) to be synthesized as carboxymethyl cellulose (CMC). Hemicellulose and lignin were first removed and later rice stubble cellulose was swollen in 30% NaOH and isopropanol as a solvent. Synthesis conditions such as chloroacetic acid content (5–7 g in 5 g of alkali cellulose), reaction temperature (50 and 70 °C) and time (180, 270 and 360 min) were investigated to obtain CMC from rice stubble (CMCr). The 7 g of chloroacetic acid at 50°C for 180 min provided the best quality of CMCr based on 5 g of rice stubble cellulose with degree of substitution, viscosity and purity of 0.64, 36.03 cP and 90.18%, respectively. The presence of carboxymethyl substituents was verified by Fourier transform infrared spectroscopy. CMCr showed commercially low viscosity material and possibly used as a film forming packaging material for food and pharmaceutical products.

Soil heavy metal contamination is an increasingly urgent problem throughout the world. Phytoremediation is a cost-effective and ecologically friendly in situ method for the remediation of heavy metal contaminated soils. Rice has the potential for use in soil remediation due to its high biomass production, however, risks related to food safety and low accumulation potential exist. Therefore, in the current study, rice stubble was used as the adsorbent in a modified rice-fish system (MRFS) to assess its accumulation capacity in a model paddy field dosed with 0–40.0 mg kg−1 Cd. The weighted mean concentration (WMC) of Cd in rice stubble increased from 0.498 to 36.365 mg kg−1 to 1.038–71.180 mg kg−1 from 0 to 60 days post-harvest (dph), and the corresponding increment rate was 107.68%, 117.42%, 157.77% and 95.73%, respectively. Sixty-days post-harvest, removal rate of Cd from contaminated soils was 1.11–1.40%, which was greater than that of the Cd-hyperaccumulator Thlaspi caerulescens. The WMC of the heavy metals Cd, Zn, Pb, Cr and Cu in rice stubble increased 51.11–97.50%, and removal rate was 1.93–2.66%. Overall, rice stubble had a high capacity of heavy metal accumulation, mainly benefiting from the synthesis effects of MRFS and the changes of accumulation mechanism within the plant from being alive until death. Notably, this study also provides a new idea for in situ, herbage-based phytoremediation of heavy metal-contaminated soils.

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to evaluate the efficacy of the fungal treatment (Pleurotus ostreatus) of urea-treated rice stubble on growth performance in slow-growing goats. Eighteen crossbred Thai-native x Anglo-Nubian male goats (average body weight: 20.4 ± 2.0 kg) were randomly assigned to three experimental total mixed rations containing 35% rice stubble (RS) that were either untreated (URS), urea treated (UTRS), or treated with urea and fungi (UFTRS). URS and UTRS were cultivated and harvested from an aseptically fungal spawn, incubated at 25–30 °C for 25 days. Indicators of growth performance were monitored, and feces were collected quantitatively to assess nutrient digestibility, during a 12-week feeding trial. All goats remained healthy throughout the experiment. The goats fed UFTRS had a lower feed conversion ratio (kg feed/kg growth) compared to goats fed URS or UTRS. Compared to URS, dietary UFTRS increased the nutrient digestibility of slow-growing goats, such as organic matter (OM) (+8.5%), crude protein (CP) (+5.5%), neutral detergent fiber (NDF) (+39.2%), and acid detergent fiber (ADF) (+27.4%). Likewise, dietary UFTRS tended to increase rumen ammonia concentrations, but rumen pH and volatile fatty acids were not affected by UFTRS. In conclusion, the present study indicates that the fungal treatment of RS is an effective tool to improve the growth performance of slow-growing goats.

Rice ratoon technology has a great potential to be developped in a tidal swamp because it can resolve various obstacles such as limited of production factor and labor, the time of planting which is depends on the season. The objective of this paper is to analyse the effect of the stubble cutting height after harvesting of first crop on the vegetative and reproductive phase of ratoon rice. The rice was planted in a tidal swamp using a direct seedling system. A randomized block design with five replicates was used. The treatment was the stubble cutting height ranged from 10, 20, 30, 40 and 50 cm from the surface of the soil. The results showed that the height of stubble cutting has significant effect on the vegetative and reproductive phases of rice ratoon. The plant height, number of tillers and number of productive tillers of ratoon was lower than first crop. The flowering of rice ratoon was faster than the first crop. Stubble cutting up to 50 cm from the surface of the soil increases plant height, number of tillers and number of productive tillers and accelerate flowering of rice ratoon. It can be known the impact of the height of stubble cutting to the vegetative and reproductive phase on rice ratoon. Future studies on effect of the height of stubble cutting for rice yield prodcution should be focussed after the ripening phase.

In recent years, Fusarium head blight (FHB) outbreaks have occurred much more frequently in China. The reduction of burning of the preceding crop residues is suggested to contribute to more severe epidemics as it may increase the initial inoculum. In this study, a large number of Fusarium isolates was collected from blighted wheat spikes as well as from rice stubble with perithecia originating from nine sampling sites in five provinces in Southern China. Fusarium asiaticum dominated both wheat and rice populations, although rice populations showed a higher species diversity. Chemotype analysis showed that rice is the preferred niche for NIV mycotoxin producers that were shown to be less virulent on wheat. In contrast, 3ADON producers are more prevalent on wheat and in wheat producing areas. The 3ADON producers were shown to be more virulent on wheat, revealing the selection pressure of wheat on 3ADON producers. For the first time, members of the Incarnatum-clade of Fusarium Incarnatum-Equiseti Species Complex (FIESC) were found to reproduce sexually on rice stubble. The pathogenicity of FIESC isolates on wheat proved very low and this may cause the apparent absence of this species in the main wheat producing provinces. This is the first report of the Fusarium population structure including rice stubble as well as a direct comparison with the population on wheat heads in the same fields. Our results confirm that the perithecia on rice stubble are the primary inoculum of FHB on wheat and that cropping systems affect the local Fusarium population. [ABSTRACT FROM AUTHOR]

Rice stubble is agricultural waste consisting of cellulose which can be converted to carboxymethyl cellulose from rice stubble (CMCr) as a potential biomaterial. Plasticizer types (glycerol and olive oil) and their contents were investigated to provide flexibility for use as food packaging material. Glycerol content enhanced extensibility, while olive oil content improved the moisture barrier of films. Additionally, CMCr showed potential as a replacement for up to 50% of commercial CMC without any changes in mechanical and permeability properties. A mixture of plasticizers (10% glycerol and 10% olive oil) provided blended film with good water barrier and mechanical properties comparable with 20% individual plasticizer. Principle component (PC) analysis with 2 PCs explained approximately 81% of the total variance, was a useful tool to select a suitable plasticizer ratio for blended film production. Therefore, CMCr can be used to form edible film and coating as a renewable environmentally friendly packaging material. [ABSTRACT FROM AUTHOR]

This investigation aims to study the value of synthesized zeolite in reducing greenhouse gasses (GHGs) emitted by rice stubble. The experiment was divided into 2 parts. Part I comprised a study of the efficiency of GHGs reduction by synthesized zeolite and part II involved application of synthesized zeolite to reduce the cumulative GHGs emissions over 110 days from paddy rice cultivation in Khlong 4, Pathum Thani Province. The experiments comprised 2 treatments: untreated control (I), and rice stubble with addition of synthesized zeolite (II). The study measured changes in the emissions of CH4 and CO2, conducted 3 d per week for 1.30 h during the cultivation period. The results showed that rice stubble synthesized zeolite could reduce GHGs CH4 and CO2 under irrigated conditions. In the experiment, synthesized zeolite had an efficiency of 8.91% and 24.5% in reducing CH4 and CO2, respectively. Footprint analysis showed that both gases were continuously emitted throughout cultivation. In Cumulative emissions from the control treatment were 42.57 g CH4 m-2 crop and 86.40 g CO2 m-2 crop. Zeolite addition reduced emission levels to 30.71 g CH4 m-2 crop and 57.77 g CO2 m-2 crop. The reduction efficiencies CH4 and CO2 were 27.87% and 33.14%, respectively. It can be concluded that the rice stubble synthesized zeolite was capable of reducing GHGs significantly and that the efficiency was rate-dependent. It was clear that the GHGs emission reduction rate of synthesized zeolite was 0.148 g CH4 m-2 g zeolite and 0.358 g CO2 m-2 g zeolite.

The disposal of rice stubbles after harvest of crop remains a major concern in all rice growing areas. In lowland rice ecosystems, where sole cropping is mostly practiced, low energy in situ composting may contribute tremendously towards recycling of solid waste and long-term sustenance of soil fertility. Spraying of a bacteria, isolated and characterized for its cellulose degrading ability (CDM), was done singly or in consortium with Azospirillum sp or with Bacillus sp or with both to rice stubbles under field condition after harvest of the crop. Spraying with glyphosate, or with glyphosate and sugar significantly reduced stubble dry weight, and carbon content during the three months period. Consortium of CDM, Azospirillum sp and Bacillus sp performed better compared to the others. Further works may complement the findings of the present study into a low energy, simple and easily acceptable in situ rice stubble management technology. [ABSTRACT FROM AUTHOR]

The substantial amount of agricultural waste associated with rice stubble is a critical issue in Thailand as it still contains a high amount of cellulose. Thus, the conditions for cellulose isolation from Thai rice stubble were developed. It was found that cellulose at a higher Na OH concentration (10%) or higher isolation temperature provided a higher whiteness index ( WI) value and α-cellulose content after 3 h of isolation process. Extraction using 10% Na OH at 55 °C for 3 h was determined as optimum conditions for the isolation of cellulose from rice stubble. The removal of most hemicelluloses and lignin was confirmed by Fourier transform infrared spectroscopy. The yield, WI value and α-cellulose content of rice stubble cellulose were 30.67%, 75.69% and 90.05%, respectively. Cellulose from rice stubble is suitable for use as fibre or for the synthesis of cellulose derivatives that are widely used in food and pharmaceutical products. [ABSTRACT FROM AUTHOR]

The present paper describes the methodology and results of assessment of seasonal progress of rice stubble burning for 10 major rice growing districts of Haryana state in India. These 10 districts contribute about 84 per cent of total rice area of the state. As the rice fields are immediately required to be vacated for the sowing of next crop the farmers opt for mechanized harvesting and easy way out of burning the stubbles in the field. Such burning result in release of polluting gases and aerosols. Besides, the heating of the soil kills the useful micro-flora of the soil causing soil degradation. Multi-date AWiFS data from Resourcesat 1 and 2 satellites acquired between October 16, 2013 to November 26, 2013 were used for estimating paddy stubble burning areas at different intervals for the year 2013 crop growing season. In season collected ground truth data using hand held GPS along with field photographs were used to identify paddy stubble burning areas and other land features. Complete enumeration approach and Iterative Self-organizing Data Analysis Technique (ISODATA) unsupervised classifier was used for digital analysis. Normalized Difference Vegetation Index (NDVI) of each date was also used with other spectral bands of temporal images. To improve the classification accuracy the non-agricultural areas were masked out. The area was estimated by computing pixels under the classified image mask. Progress of paddy stubble burning was estimated at different intervals for the year 2013 using available cloud free multi-date IRS-P6 AWiFS data to identify the crucial period when stubbles burning takes place in major area so that preventive measures can be taken to curb the menace. [ABSTRACT FROM AUTHOR]

Rice ratoon technology has a great potential to be developped in a tidal swamp because it can resolve various obstacles such as limited of production factor and labor, the time of planting which is depends on the season. The objective of this paper is to analyse the effect of the stubble cutting height after harvesting of first crop on the vegetative and reproductive phase of ratoon rice. The rice was planted in a tidal swamp using a direct seedling system. A randomized block design with five replicates was used. The treatment was the stubble cutting height ranged from 10, 20, 30, 40 and 50 cm from the surface of the soil. The results showed that the height of stubble cutting has significant effect on the vegetative and reproductive phases of rice ratoon. The plant height, number of tillers and number of productive tillers of ratoon was lower than first crop. The flowering of rice ratoon was faster than the first crop. Stubble cutting up to 50 cm from the surface of the soil increases plant height, number of tillers and number of productive tillers and accelerate flowering of rice ratoon. It can be known the impact of the height of stubble cutting to the vegetative and reproductive phase on rice ratoon. Future studies on effect of the height of stubble cutting for rice yield prodcution should be focussed after the ripening phase. [ABSTRACT FROM AUTHOR]

Efecto de rastrojos en el nitrógeno de biomasa microbiana en un agroecosistema arrocero inundado. Del año 2002 al 2004 se investigó en un agroecosistema arrocero inundado a fin de evaluar cambios en la actividad de la biomasa microbiana y su contenido de nitrógeno "N", durante cuatro ciclos consecutivos del cultivo. Se comparó la tendencia del contenido de nitrógeno de la biomasa microbiana "NBM" en los sistemas siembra directa sobre rastrojos "SDR" y labranza mecanizada convencional "LMC". Durante el tercer ciclo de arroz se evaluó el efecto de los rastrojos de mucuna Mucuna deeringiana (Bort.) Merr; se comparó la materia orgánica del suelo "MOS" y el NBM. Adicionalmente, durante el cuarto ciclo de arroz del estudio, fueron contrastados cambios en la actividad de la biomasa microbiana en tres diferentes etapas de crecimiento del cultivo. En los primeros 5 cm del perfil del suelo la cantidad de NBM siempre fue mayor en SDR. En esta capa del suelo, la combinación de rastrojos de arroz acumulados durante tres ciclos con rastrojos de mucuna del ciclo previo, permitió una mayor estratificación de la MOS. Se observó un incremento de la MOS de 2,3 a 4,1%, mientras que el NBM fue casi cuatro veces mayor. La respiración de los microorganismos del suelo y la mineralización del N fue afectada principalmente por la presencia continua de una lámina de agua sobre el suelo. Se concluyó que la SDR es un sistema capaz de complementar la fertilización química e incrementar los rendimientos del arroz mediante la gradual liberación de N y otros nutrimentos derivados de la descomposición de los rastrojos.

Copyright of Journal of Plant Protection Research is the property of Institute of Plant Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the first known values for emissions of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/Fs) from combustion of agricultural field biomass. Wheat and rice straw stubble collected from two western US states were tested in a field burn simulation to determine emission factors. The resulting emission factor was approximately 0.5 ng toxic equivalency (TEQ)/kg burned for both sources. When coupled with published agricultural data on crop residue burning, about 1 g TEQ/year can be expected from wheat and rice straw residue burning, making this an apparently minor source of PCDDs/Fs in the United States. [Copyright &y& Elsevier]

Soil heavy metal contamination is an increasingly urgent problem throughout the world. Phytoremediation is a cost-effective and ecologically friendly in situ method for the remediation of heavy metal contaminated soils. Rice has the potential for use in soil remediation due to its high biomass production, however, risks related to food safety and low accumulation potential exist. Therefore, in the current study, rice stubble was used as the adsorbent in a modified rice-fish system (MRFS) to assess its accumulation capacity in a model paddy field dosed with 0–40.0 mg kg−1 Cd. The weighted mean concentration (WMC) of Cd in rice stubble increased from 0.498 to 36.365 mg kg−1 to 1.038–71.180 mg kg−1 from 0 to 60 days post-harvest (dph), and the corresponding increment rate was 107.68%, 117.42%, 157.77% and 95.73%, respectively. Sixty-days post-harvest, removal rate of Cd from contaminated soils was 1.11–1.40%, which was greater than that of the Cd-hyperaccumulator Thlaspi caerulescens. The WMC of the heavy metals Cd, Zn, Pb, Cr and Cu in rice stubble increased 51.11–97.50%, and removal rate was 1.93–2.66%. Overall, rice stubble had a high capacity of heavy metal accumulation, mainly benefiting from the synthesis effects of MRFS and the changes of accumulation mechanism within the plant from being alive until death. Notably, this study also provides a new idea for in situ, herbage-based phytoremediation of heavy metal-contaminated soils. ga1 • Using stubble for heavy metal adsorption after rice harvest avoided food safety risks. • The principle of "Rice-fish" co-culture system was implemented in the method. • The accumulation capacity of rice plant increased a lot from being alive to death. • The method had high accumulation capacity of Cd. [ABSTRACT FROM AUTHOR]

The colonization pattern and extent of decay produced in paddy stubble by soil inhabiting mycoflora were done by using nylon net bag technique. Among the three methods used for isolation of fungi, dilution plate technique recorded the highest number of fungi followed by damp chamber and direct observation method. Nutrient availability and climatic conditions (temperature, humidity and rainfall) influenced the occurrence and colonization pattern of fungi. Maximum fungal population was recorded in October (48.99 × 10(4)/g dry litter) and minimum in May (11.41 × 10(4)/g dry litter). Distribution of Deuteromycetous fungi was more in comparison to Zygomycetes, oomycetes and ascomycetes. In the early stage of decomposition Mucor racemosus, Rhizopus nigricans, Chaetomium globosum and Gliocladium species were found primarly whereas at later stages of decomposition preponderance of Aspergillus candidus, Torula graminis, Cladosporiun cladosporioides and Aspergillus luchuensis was recorded.