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1.
Environ Res ; 258: 119351, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38844030

RESUMO

The sustainable management of huge volume of agricultural waste in India can be resolved through composting and used as soil amendment. Agriculture waste compost amendments can optimistically alter the physicochemical (pH, C, N, & P) as well as biological nature (microbial activity/biomass and enzymatic activity) of infertile soil. Hence this study, the agriculture wastes such as sugarcane trash, corn stover, and pearl millet stalks were converted to composite through decomposition pit. Interestingly, test crops residues individual composites and their mixed form contained considerable quantity of vital elements like TC, TN, TP, TK, and C:N ratio and can effectively convert infertile soil to fertile soil. These test crop composites also had a significant impact on MBN (42.3 µg g-1), MBC (198.4 µg g-1), and MBP (196.4 µg g-1) in test soil, as well as dehydrogenase and alkaline phosphatase enzyme activity. However, the mixed composite effects are significantly greater than the individual test crop composite effects. Furthermore, it effectively remediates/converts infertile soil to fertile soil, and it ultimately demonstrated positive effects on Vigna mungo biometric (SH, RH, WB, and DB) and biomolecule (total chlorophyll, total carbohydrate, and total proteins) profiles, followed by individual test crop composites. According to the findings of this study, the incorporation of crop residue-based mixed composite significantly transforms infertile soil into fertile soil and promotes the growth of V. mungo.


Assuntos
Compostagem , Produtos Agrícolas , Solo , Vigna , Solo/química , Vigna/crescimento & desenvolvimento , Vigna/química , Produtos Agrícolas/crescimento & desenvolvimento , Compostagem/métodos , Índia , Zea mays/crescimento & desenvolvimento , Agricultura/métodos
2.
Phytopathology ; 114(1): 269-281, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37505095

RESUMO

Fungicide resistance in foliar fungal pathogens is an increasing challenge to crop production. Yield impacts due to loss of fungicide efficacy may be reduced through effective surveillance and appropriate management intervention. For stubble-borne pathogens, off-season crop residues may be used to monitor fungicide resistance to inform pre-planting decisions; however, appropriate sampling strategies and support sizes for crop residues have not previously been considered. Here, we used Pyrenophora teres f. teres (Ptt) with resistance to demethylase inhibitor fungicides as a model system to assess spatial dependency and to compare the effects of different sampling strategies and support sizes on pathogen density (Ptt DNA concentration) and the frequency of fungicide resistance mutation. The results showed that sampling strategies (hand-picked versus raked) did not affect estimates of pathogen density or fungicide resistance frequency; however, sample variances were lower from raked samples. The effects of differing sample support size, as the size of the collection area (1.2, 8.6, or 60 m2), on fungicide resistance frequency were not evident (P > 0.05). However, measures of pathogen density increased with area size (P < 0.05); the 60 m2 area yielded the highest Ptt DNA concentration and produced the lowest number of pathogen-absent samples. Sample variances for pathogen density and fungicide resistance frequency were generally homogeneous between area sizes. The pattern of pathogen density was spatially independent; however, spatial dependency was identified for fungicide resistance frequency, with a range of 110 m, in one of the two fields surveyed. Collectively, the results inform designs for monitoring of fungicide resistance in stubble-borne pathogens.


Assuntos
Ascomicetos , Fungicidas Industriais , Hordeum , Fungicidas Industriais/farmacologia , Hordeum/microbiologia , Doenças das Plantas/microbiologia , DNA , Análise Espacial
3.
Arch Anim Nutr ; 78(2): 125-141, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38907616

RESUMO

In Africa, a wide variety of diets (forage + crop co-products or other agricultural by-products) is being used by livestock farmers in different production systems to adapt to climate change. This study aimed to assess the performance of various local feeding strategies on Sudanese Fulani zebu cattle. Two experiments were carried out on 10 steers aged initially 33 months (142 kg body weight - BW). The animals were fed eight different diets at an intake level of 3.2% LW in dry matter (DM), including two control diets of 100% rangeland forage (100% RF) and six experimental diets made up of forage and crop co-products (75:25 DM ratio). In the first experiment, the control diet was made up of rangeland forage (RF) and supplements consisted of four cereal co-products (CC), i.e. maize, sorghum, millet, and rice straws. In the second experiment, the control diet consisted of Panicum maximum (Pmax) hay, and the supplements tested were two legume co-products (LC), i.e. cowpea and peanut haulms. Each experiment lasted 3 weeks, including 2 weeks of adaptation to the diet and 1 week of data collection on individual animals (intake, apparent digestibility, and enteric methane). The NDF content of the diets was different within each experiment (p < 0.05). Among diets containing CC, DM intake [g/kg BW] was significantly higher (+31%; p = 0.025) for the diet containing rice straw than for the other diets, which showed similar levels to the RF diet. Among diets containing LC, intake was significantly higher (p = 0.004) than for the Pmax diet. Intake was higher for the peanut haulm diet than for the cowpea haulm diet. The DM digestibility was similar between the different diets in each experiment. Enteric methane (eCH4) yield [g/kg DMI] from the CC and LC-containing diets were reduced by an average of 23% and 20% compared to the RF and Pmax control diets respectively. Raising awareness among agro-pastoralists about the use of crop co-products offers real prospects for eCH4 emissions mitigation in the Sahel region.


Assuntos
Ração Animal , Dieta , Animais , Ração Animal/análise , Bovinos/fisiologia , Dieta/veterinária , Masculino , Suplementos Nutricionais/análise , Fenômenos Fisiológicos da Nutrição Animal , Metano/metabolismo , Sorghum/química , Arachis/química , Digestão/fisiologia , Digestão/efeitos dos fármacos , Zea mays/química , Vigna/química , Oryza/química
4.
Glob Chang Biol ; 29(24): 6846-6855, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37800369

RESUMO

Crop residues are important inputs of carbon (C) and nitrogen (N) to soils and thus directly and indirectly affect nitrous oxide (N2 O) emissions. As the current inventory methodology considers N inputs by crop residues as the sole determining factor for N2 O emissions, it fails to consider other underlying factors and processes. There is compelling evidence that emissions vary greatly between residues with different biochemical and physical characteristics, with the concentrations of mineralizable N and decomposable C in the residue biomass both enhancing the soil N2 O production potential. High concentrations of these components are associated with immature residues (e.g., cover crops, grass, legumes, and vegetables) as opposed to mature residues (e.g., straw). A more accurate estimation of the short-term (months) effects of the crop residues on N2 O could involve distinguishing mature and immature crop residues with distinctly different emission factors. The medium-term (years) and long-term (decades) effects relate to the effects of residue management on soil N fertility and soil physical and chemical properties, considering that these are affected by local climatic and soil conditions as well as land use and management. More targeted mitigation efforts for N2 O emissions, after addition of crop residues to the soil, are urgently needed and require an improved methodology for emission accounting. This work needs to be underpinned by research to (1) develop and validate N2 O emission factors for mature and immature crop residues, (2) assess emissions from belowground residues of terminated crops, (3) improve activity data on management of different residue types, in particular immature residues, and (4) evaluate long-term effects of residue addition on N2 O emissions.


Assuntos
Produtos Agrícolas , Óxido Nitroso , Óxido Nitroso/análise , Solo/química , Poaceae , Biomassa , Nitrogênio/análise , Agricultura , Fertilizantes
5.
Environ Sci Technol ; 57(8): 3031-3041, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36790312

RESUMO

Tenebrio molitor and Tenebrio obscurus (Coleoptera: Tenebrionidae) larvae are two commercial insects that eat plant and crop residues as diets and also biodegrade synthetic plastics polyethylene (PE). We examined biodegradation of low-density PE (LDPE) foam (Mn = 28.9 kDa and Mw = 342.0 kDa) with and without respective co-diets, i.e., wheat brain (WB) or corn flour (CF), corn straw (CS), and rice straw (RS) at 4:1 (w/w), and their gut microbiome and genetic metabolic functional groups at 27.0 ± 0.5 °C after 28 days of incubation. The presence of co-diets enhanced LDPE consumption in both larvae and broad-depolymerized the ingested LDPE. The diet type shaped gut microbial diversity, potential pathways, and metabolic functions. The sequence of effectiveness of co-diets was WB or CF > CS > RS for larval development and LDPE degradation. Co-occurrence networks indicated that the larvae co-fed with LDPE displayed more complex correlations of gut microbiome than the larvae fed with single diets. The primary diet of WB or CF and crop residues CS and RS provided energy and nitrogen source to significantly enhance LDPE biodegradation with synergistic activities of the gut microbiota. For the larvae fed LDPE and LDPE plus co-diets, nitrogen fixation function was stimulated compared to normal diets and associated with LDPE biodegradation.


Assuntos
Besouros , Microbioma Gastrointestinal , Tenebrio , Animais , Larva/metabolismo , Tenebrio/metabolismo , Polietileno , Poliestirenos , Carbono/metabolismo , Besouros/metabolismo , Dieta
6.
Trop Anim Health Prod ; 55(6): 377, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37878030

RESUMO

Small ruminants are of great importance to the livelihoods of many people in Sub-Saharan Africa (SSA) since they act as a source of meat, income, hides and skins and for cultural identity. Despite their great importance, especially to rural smallholder farmers, their production in Africa is hindered by poor nutrition. The first stage of establishing development strategies to increase feed quality and quantity is to conduct a comprehensive inventory of the feed resources that are currently available, especially in SSA. Therefore, this study aims to evaluate the availability and nature of the common feed resources that are used in the feeding of small ruminants in Uganda. This study involved a comprehensive review of various scientific, technical and economic literature that has been published up to date. Our results show that the available feed resources in Uganda can be grouped mainly into:- crop wastes and residues, agro-industrial by-products, conserved feeds, natural pastures and browse. The main feed resources for small ruminants in Uganda have been identified as natural pastures, which are generally characterised by a low nutritive value. However, browses are seen to have a high crude protein content and could be used as a supplement to grass forages and crop residues. It has been noted that farmers lack knowledge related to feed processing and management, in addition to a lack of policy governing feed quality. Therefore, there is a need to train farmers on how to process and utilise crop residues, in addition to proper feed management practices like pasture cultivation and conservation. It is also necessary to introduce widely new pasture species with better nutritional values that are suitable for the local production systems.


Assuntos
Desnutrição , Estado Nutricional , Humanos , Animais , Uganda , Valor Nutritivo , Desnutrição/veterinária , Ruminantes
7.
J Sci Food Agric ; 102(6): 2445-2453, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34636045

RESUMO

BACKGROUND: The growing food-feed-fuel competition, declining availability of traditional feeds, higher prices, and the urgent need to provide long-term sustainability for animal production have all triggered global research into the optimum extraction of energy and nutrients from lignin-rich plant biomass. Recent studies have shown that the Pleurotus species of white rot fungus can selectively degrade lignin in lignin-rich plant biomass; however, its effectiveness in selectively degrading lignin depends on the type of substrate and species of fungus. This study was therefore designed to treat wheat straw, rice straw, and corn cob, with Pleurotus eryngii, P. ostreatus, and P. florida for 30 days under solid-state fermentation, to identify a promising fungus-substrate combination for the selective degradation of lignin and optimal improvement in the nutritional value and digestibility of each substrate. RESULTS: The type of fungus strongly influenced (P < 0.01) selectivity in lignin degradation, and the level of improvement in crude protein (CP), in vitro dry matter digestibility (IVDMD), and in vitro gas production (IVGP), in wheat straw, rice straw, and corn cob. Fungus-substrate interaction data revealed that P. ostreatus caused maximum (P < 0.05) degradation of lignin, and greater (P < 0.05) improvement in CP, IVDMD, and IVGP in wheat straw and rice straw. The lowest (P < 0.05) degradation of lignin and improvement in CP, IVDMD, and IVGP was caused by P. eryngii in corn cob. Among the fungi, the maximum (P < 0.05) degradation of lignin, and greater (P < 0.05) improvement in CP, IVDMD, and IVGP were caused by P. florida as compared with those of P. ostreatus and P. eryngii. CONCLUSION: The results highlight significant influence of fungus-substrate combination for selective lignin degradability and the consequent improvement in the nutritional value of the substrates. Maximum selective lignin degradability and improvement in nutritional value and digestibility was caused by P. ostreatus in wheat straw and in rice straw, and by P. florida in corn cob. © 2021 Society of Chemical Industry.


Assuntos
Oryza , Pleurotus , Ração Animal/análise , Animais , Fermentação , Lignina/metabolismo , Valor Nutritivo , Oryza/metabolismo , Pleurotus/metabolismo , Triticum/metabolismo , Zea mays/metabolismo
8.
Environ Monit Assess ; 195(1): 171, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36459271

RESUMO

The intensification of specific land management operations (tillage, herbicide, etc.) is increasing land degradation and contributing to ecosystem pollution. Mulches can be a sustainable tool to counter these processes. This is particularly relevant for rural areas in low-income countries where agriculture is a vital sector. In this research, the environmental impact of different rates of wheat residues (no residues, 25, 50, 75, and 100%) in corn silage cultivation was evaluated using the life cycle assessment (LCA) method under conventional tillage (CT) and no-tillage (NT) systems in a semi-arid region in Karaj, Iran. Results showed that in both tillage systems, marine aquatic ecotoxicity (ME) and global warming potential (GWP) had the highest levels of pollution among the environmental impact indicators. In CT systems, the minimum (17,730.70 kg 1,4-dichlorobenzene (DB) eq.) and maximum (33,683.97 kg 1,4-DB eq.) amounts of ME were related to 0 and 100% wheat residue rates, respectively. Also, in the CT system, 0 and 100% wheat residue rates resulted in minimum (176.72 kg CO2 eq.) and maximum (324.95 kg CO2 eq.) amounts of GWP, respectively. However, in the NT system, the 100% wheat residue rate showed the minimum amounts of ME (11,442.39 kg 1,4-DB eq.) and GWP (120.21 kg CO2 eq.). Also, in the NT system, maximum amounts of ME (17,174 kg 1,4-DB eq.) and GWP (175.60 kg CO2 eq.) were observed with a zero wheat residue rate. On-farm emissions and nitrogen fertilizers were the two factors with the highest contribution to the degradation related to environmental parameters at all rates of wheat residues. Moreover, in the CT system, the number of environmental pollutants increased with the addition of a higher wheat residue rate, while in the NT system, increasing residue rates decreased the amount of environmental pollutants. In conclusion, this LCA demonstrates that the NT system with the full retention of wheat residues (100%) is a more environmentally sustainable practice for corn silage production. Therefore, it may be considered one of the most adequate management strategies in this region and similar semi-arid conditions. Further long-term research and considering more environmental impact categories are required to assess the real potential of crop residues and tillage management for sustainable corn silage production.


Assuntos
Poluentes Ambientais , Silagem , Zea mays , Triticum , Ecossistema , Dióxido de Carbono , Monitoramento Ambiental
9.
Trop Anim Health Prod ; 54(2): 92, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35137252

RESUMO

The insufficiency and variability of pasture production is a determining factor in milk production, particularly in the Sahelian zone. The objective of this study was to characterize dairy production systems and their relationship with crops to meet livestock needs. It consisted of surveys of 120 farmers in four communes in the Séno province. The results show three groups of dairy farmers that are essentially differentiated by the main activity and the sex of the farmers as well as the size of the cattle herd on the farm. The first group is made of male agropastoralists, with herds averaging 12 cattle. Group 2 consists of male agropastoralists with an average of 22 cattle. Group 3 consists of female pastoralists (96.15%), with a herd size of about 19 head. The cows are fed on pasture and supplemented with crop residues and cottonseed cake. The supplementation is more important in group 2, where more farmers have hayloft for fodder conservation and manure pits compared to the other two groups. Crop residues are used primarily as feed in all groups from January to May. This supplementation allows the maintenance of milk production in the dry season and group 2, with more dairy cows, records more milk milked (6.5 and 3.8 l) and consumed in wet and dry seasons compared to the other two groups. The results suggest that the farmers in the area have low technical level and need capacity building in improved agro-pastoral production techniques to increase their production.


Assuntos
Ração Animal , Indústria de Laticínios , Agricultura , Ração Animal/análise , Animais , Burkina Faso , Bovinos , Fazendas , Feminino , Lactação , Leite
10.
Trop Anim Health Prod ; 54(2): 115, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35220483

RESUMO

An experiment was executed to determine the effects of replacing wheat straw with corn stover on growth performance, behavioral characteristics, blood metabolites, and nutrient digestibility in Beetal bucks (23.92 ± 0.79 kg; age = 10 ± 1 month). A total of twenty four Beetal bucks were assigned randomly to one of three treatment groups, having eight animals each, for 15-week experimental period excluding adaption period of 2 weeks. The dietary treatments included conventional (25% wheat straw and 75% concentrate), corn stover 50 (50% of wheat straw (12.5%) was replaced with corn stover), and corn stover 100 (wheat straw was completely replaced with corn stover). Parameters were evaluated regarding growth performance, behavioral recording, digestibility, chemical analysis of feed and fecal materials, rumen pH, fecal score, and blood metabolite measurements. Dietary replacement of wheat straw with corn stover has resulted in an increased dry matter intake and average daily gain significantly (P ≤ 0.05) by 10 and 26%, respectively in the bucks. Rumen pH and fecal score, however, remained unaffected by dietary replacement of wheat straw with corn stover in the bucks. The replacement of wheat straw with corn stover has resulted in an increased feeding and rumination time, improved lying time and length, and decreased number of bouts in the bucks. Blood glucose, urea, bilirubin, and calcium levels were remained unaffected by replacing wheat straw with corn stover. The blood phosphorous level, however, was lower in bucks fed corn stover-based ration. The bucks fed corn stover-based ration has resulted in an increased digestibility of organic matter, crude protein, and neutral and acid detergent fiber compared to those fed wheat straw-based total mixed ration. It was concluded that replacement of wheat straw with corn stover as fiber residue in the ration of bucks has resulted in an increased dry matter intake and higher average daily gain, improved behavioral characteristics, and higher nutrient digestibility.


Assuntos
Triticum , Zea mays , Ração Animal/análise , Animais , Dieta/veterinária , Fibras na Dieta/metabolismo , Digestão , Nutrientes , Rúmen/metabolismo , Triticum/metabolismo , Zea mays/metabolismo
11.
Waste Manag Res ; 40(6): 698-705, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34387123

RESUMO

Lignocellulosic by-products from agricultural crops represent an important raw material for anaerobic digestion and clean renewable, which is a key component of the circular economy. Lignocellulose is recalcitrant to biodegradation and pretreatments are required to increase methane yield during anaerobic digestion. In this work, the efficacy of different physicochemical pretreatments was compared using corn stover biomass as substrate. Anaerobic digestion of untreated and pretreated corn stover was performed in batch mode at mesophilic temperature (38°C) and organic matter solubilization of pretreated substrates was also investigated. The highest organic matter solubilization occurred in autoclave pretreatment (soluble chemical oxygen demand = 5630 ± 42 mg O2 L-1). However, the highest methane yield was obtained using alkaline pretreatment (367 ± 35 mL CH4 g-1 VSadded). Alkaline pretreatment increased methane yield by 43.3% compared to untreated control (256 ± 15 mL CH4 g-1 VSadded). Two mathematical models (i.e. first-order kinetics and transfer function) were utilized to fit the experimental data with the aim of assessing anaerobic biodegradation and to obtain the kinetic constants in all cases studied. Both models adequately fit the experimental results. The kinetic constant, k, of the first-order model increased by 92.8% when stover was pretreated with sulphuric acid compared with control. The transfer function model revealed that the maximum methane production rate, Rm, was obtained for the sulphuric acid treatment, which was 63.5% higher compared to control.


Assuntos
Metano , Zea mays , Anaerobiose , Biocombustíveis , Análise da Demanda Biológica de Oxigênio , Biomassa , Zea mays/metabolismo
12.
J Appl Microbiol ; 130(1): 208-216, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32619320

RESUMO

AIMS: The aims of this study were to determine the occurrence of Fusarium graminearum species complex (FGSC) on soybean pods, seeds and roots, including rhizoplane, during the period of soybean crop in rotation with wheat and to evaluate the FGSC dynamics on wheat and soybean residues during two soybean growing seasons in rotation with wheat, particularly F. graminearum sensu stricto (FGss). METHODS AND RESULTS: Soybean roots, pods and seeds were analysed during 2012/13 and 2013/14 seasons. The morphological identification of FGSC and mycotoxin analysis was done. Crop residues were taken in both soybean season in wheat rotation and FGss were quantificated by real-time PCR. The results showed that Fusarium species, mainly FGSC, survive in a soybean crop in rotation with wheat. Isolation frequency of these species was higher on soybean pods than on seeds at R6 stage. Deoxynivalenol contamination on soybean seeds was higher in the 2013/14 season in comparison with the 2012/13 season. Low isolation levels of Fusarium species and species that did not belong to FGSC were observed in soybean root, whereas in rhizoplane a higher level was observed. Fusarium species inoculum on residues remained stable during crop succession and the FGSC were recovered from both wheat and soybean residues. Real time PCR data showed a higher DNA concentration of FGss in wheat residues in the first developmental stages of soybean plants, being the levels more significant during 2012/13 season. With regard to soybean residues collected during the wheat growing stages, an increase in DNA from anthesis until wheat harvest was observed. CONCLUSIONS: In a no-till production system, the populations of FGSC can colonize wheat and soybean residues to become an inoculum source. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides new data on the occurrence of FGSC populations in soybean plant and FGss on residues in soybean-wheat rotation, a cultural practice commonly used in in Argentina.


Assuntos
Agricultura/métodos , Fusarium/isolamento & purificação , Glycine max/microbiologia , Triticum/microbiologia , Argentina , Fusarium/classificação , Fusarium/genética , Micotoxinas/análise , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Sementes/química , Sementes/microbiologia , Glycine max/química , Tricotecenos/análise , Triticum/química
13.
J Basic Microbiol ; 61(8): 721-735, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34251681

RESUMO

This study was aimed to assess the suitability of four fungal species for operating in the residues of three crops in Golestan province, Iran. For this, four experiments were conducted to analyze their ability to grow on five culture media (Experiment I) and on the residues (Experiment II) and their growth responses to different pHs (Experiment III) and temperature levels (Experiment IV). Then, the possibility of establishing these fungi in the cultivated lands of studied crops was examined. Fungal growth was high on soybean and cotton residues and low on those of rice, and all the fungi produced a significant reduction in the carbon to nitrogen ratios in relation to noninoculated residues. The amount of nitrogen in fungal-treated cotton residues increased about four times compared with the control and in other studied residues increased twice as much as the control. The lowest C:N values for cotton and rice residues were found for Pleurotus ostreatus while Aspergillus niger was the most efficient for those of soybean. The results also showed that these fungi will not show the best performance in respect to temperature and pH, but will not be ineffective. The results could be the basis for further studies on the use of these fungi to improve nutrient cycling, focusing on multicriteria zoning on climatic and soil-related components.


Assuntos
Produtos Agrícolas/microbiologia , Fungos/fisiologia , Aspergillus niger , Carbono , Fungos/patogenicidade , Gossypium/microbiologia , Concentração de Íons de Hidrogênio , Irã (Geográfico) , Nitrogênio , Oryza/microbiologia , Pleurotus/crescimento & desenvolvimento , Solo , Glycine max , Temperatura
14.
J Environ Manage ; 300: 113753, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34537561

RESUMO

The use of pesticides has been increasing in recent years for maintaining traditional agricultural practices. However, these chemicals are associated with several environmental impacts, demanding urgent remediation techniques. Biochar is a carbonaceous material produced by pyrolysis that has the potential for pesticide sorption and remediation. In this context, this interdisciplinary review systematically assessed the state of the knowledge of crop residues to produce biochar for pesticide sorption. We focused on maize, rice, and wheat residues since these are the three most-produced grains worldwide. Besides, we evaluated different biochar handling, storage, and soil dispersion techniques to ease its implementation in agriculture. In general, pyrolysis temperature influences biochar characteristics and its potential for pesticide sorption. Furthermore, biochar amended soils had greater pesticide sorption capacity, limiting potential leaching and runoff. Most studies showed that the feedstock and specific surface area influence the biochar sorption properties, among other factors. Also, biochar reduces pesticides' bioavailability, decreasing their toxicity to soil organisms and improving soil fertility and crop yields. Nonetheless, the retrieved papers assessed only 21 pesticides, mainly consisting of lab-scale batch experiments. Therefore, there is still a gap in studies evaluating biochar aging, its potential desorption, pesticide co-contaminations, the associated microbiological processes, and field applications. Determining flow properties for biochars of different sizes and pellets is vital for reliable handling equipment design, and performing techno-economic assessment under different farm contexts is encouraged. Ultimately, coupling biochar production with residue management could address this challenge on sustainable agricultural systems.


Assuntos
Recuperação e Remediação Ambiental , Oryza , Praguicidas , Poluentes do Solo , Adsorção , Carvão Vegetal , Solo , Poluentes do Solo/análise , Triticum , Zea mays
15.
Anim Feed Sci Technol ; 262: 114419, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32255896

RESUMO

Feed scarcity is a major challenge for livestock production in West Africa, especially during the dry season when grass quality and quantity on grazing lands are inadequate. In the dry season, crop residues are a key source of livestock feed. The residues of grain legumes, also known as grain legume fodders (GLFs), are stored and traded for feeding in the dry season. The objectives of our experiment were to evaluate the effects of storage conditions and duration on dry matter (DM) and nutritional quality of GLFs, and to assess the risk of aflatoxin in stored groundnut fodder. The experiment was designed as a factorial trial with 18 treatment combinations with four replicates (4 farms). The treatments included: 3 types of GLFs (cowpea, groundnut and soybean fodder), 3 types of storage locations (rooftop, room and tree-fork) and 2 types of packaging (packed in polythene sacks and unpacked but tied with rope). Over a 120 day storage period, DM quantity reduced by an average of 24 % across all storage conditions, showing a range from 14 % in the best condition (sacks and rooms) to 35 % in the worst condition (bundles tied with rope and stored on rooftops or tree-forks). Soybean fodder had no leaves, the lowest crude protein content (CP) and organic matter digestibility (OMD), and the highest content of cell wall components compared to cowpea and groundnut fodder. These nutritional quality parameters in soybean fodder hardly changed during storage. Cowpea and groundnut fodder showed a decrease in leaf-to-stem ratio (LSR), CP and OMD, and an increase in the content of cell wall components during storage, but their nutritional value remained better than that of soybean fodder. Storage in sacks resulted in less DM loss, in less reduction of LSR and in a smaller increase of the content of cell wall components than storage of bundles tied with rope. Our study shows that the DM loss, the decrease in LSR, and the increase in the content of cell wall components can be prevented partly by storing GLFs in sacks instead of tying bundles with rope, and to a minor extent by storing in rooms instead of in the open air. Aflatoxin was not detectable in the groundnut fodder samples. Our results highlight that attention to storage conditions can improve the feeding value of GLFs which are key for livestock nutrition during the dry season.

16.
Asian-Australas J Anim Sci ; 33(1): 24-34, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29879812

RESUMO

OBJECTIVE: The effects of Pleurotus ostreatus on the feed utilization improvement of broad bean stalks (BBS), rape straw (RS), paddy straw (PS) and corn stalk (CS) was examined. METHODS: The four roughages were co-cultured with Pleurotus ostreatus. The chemical composition; enzyme activities of laccase, carboxymethylcellulase (CMCase) and xylanase; carbohydrate and protein fractions (based on CNCPS) were assessed at different days after inoculation (7, 14, 21, 28 d) and un-inoculated roughages (control, 0 d). The digestibility of nutrient compenentscomponents and the gas production of roughage with various incubation times were monitored at 0, 2, 4, 6, 9, 12, 24, 36, 48, 60 and 72 h using an in vitro ruminal fermentation method. RESULTS: A higher CMCase activity (0.1039 U/mL) and earlier time to peak (14 d) were detected in Pleurotus ostreatus cultured with CS (P &lt; 0.05). Significantly, the incubation length-dependent responses of cumulative gas production were observed from 24 to 72 hours post fermentation (P &lt; 0.05), and these incubation length-dependent effects on cumulative gas production of PS and CS were appeared earlier (24 h) for PS and CS than those (48 h) for BBS and RS (P &lt; 0.05). The fast-degradable carbohydrate (CA) content for all four roughages significantly increased over time (P &lt; 0.05). Nonetheless, increased degradation efficiency for CA treated with Pleurotus ostreatus was detected at both 21 and 28 days of incubation (P &lt; 0.05). With the exception of PS (P &lt; 0.05), there were no significant difference among the roughages (P &gt; 0.05) in slowly-degradable carbohydrate (CB2) at different incubation times (P &lt; 0.05). CONCLUSION: Assessment of the alterations in chemical composition, CNCPS system fractions, and the fermentation kinetics after biological pretreatment may yield valuable database for evaluating the biological pretreatment of Pleurotus ostreatus in ruminants feed.

17.
Waste Manag Res ; 38(7): 753-761, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32347193

RESUMO

Annually 500 M t organic wastes are produced in India from the agriculture sector. Transportation of bulky organic manures for centralized collection, processing and distribution to farms is cost prohibitive. Hence, recycling of agricultural wastes using vermicompost technology at the farm level is a practical way of managing agriwaste for meeting the plant nutrient requirement. Our experience with a 1.584 ha farm for three years (2015-2016 to 2017-2018) revealed that 8.1 t vermicompost was produced in three batches from 24 t agriwastes produced within the farm area. The system productivity by recycling these farm generated agriwastes and run-off water was 18.05 t (≈11.4 t ha-1) rice equivalent yield which was higher by 2.6 times as compared to rice fallow (4.46 t ha-1). Also, the net return from this system (Indian rupees 70141 ha-1) was higher by 2.3 times, after considering the fixed cost towards construction of a water recycling pond. An increase in carbon stock in soil for the four years study period was 0.66 Mg ha-1 year-1 with the agriwaste recycling system under organic nutrition. For the inorganic fertilizer plot, the increase in carbon stock was 0.53 Mg ha-1 year-1. A decrease in bulk density from 1.56 to 1.46 Mg m-3, increase in water holding capacity from 0.43 to 0.52 cm3 cm-3 and increase in available P and K content in soil from 38.0 and 174.7 kg ha-1 to 45.8 and 186.5 kg ha-1, respectively, were noted. Thus, recycling of agricultural waste at the farm level is useful in improving soil health and crop productivity.


Assuntos
Agricultura , Fertilizantes/análise , Fazendas , Índia , Solo
18.
Waste Manag Res ; 38(9): 978-986, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32594899

RESUMO

The research and application of biochars enriched with minerals have increased in recent years; however, the mineral fraction used consists of specific minerals, such as clay minerals and synthesized compounds. In this work, the effects of adding two specific soil types (sandy and clayey) to rice and coffee husks in order to generate biochars via pyrolysis was investigated. Chemical, physical-chemical, thermal, spectroscopic and crystallographic analyses were conducted on the produced biochars. The study confirmed that the presence of mineral soils during the pyrolysis process increases the yield, C retention ratio, and specific surface area. It also decreases the pH, cation exchange capacity (CEC), nutrient content, and carbon-to-nitrogen ratio of biochars. However, the biochars produced by mixing coffee husks and mineral soils still demonstrate a capacity to increase the pH and the CEC of tropical soils. In addition, increased C retention demonstrates an environmental benefit of this biochar production method. Biomass pyrolysis combined with clayey soil results in a biochar with a higher degree of aromaticity and higher thermal stability when compared to biomass pyrolysis alone. These characteristics give the biochar a recalcitrant character, without the necessity for steps related to the synthesis of specific mineral compounds, which reduces the economic and energy cost of the process.


Assuntos
Carvão Vegetal , Solo , Minerais , Temperatura
19.
J Environ Manage ; 244: 144-153, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31121501

RESUMO

To accelerate the process of decomposition using consortia of thermophilic ligno-cellulolytic fungi, different crop residues viz. sorghum (SG), soybean (SS), maize (MS), sugarcane (SC), cotton (CS) and pigeon pea (PS) with a varied C:N ratio and sawdust (SD) having high lignin content were collected and used for decomposition process. Compost quality assessed by evaluating different maturity and stability indices at five succeeding stages [first mesophilic (M1), thermophilic (T), second mesophilic (M2), cooling (C) and humification (H)]. A significant reduction was observed in the C:N ratio, biodegradability index, nitrification index, ratio of water-soluble carbon to organic nitrogen (WSC/Org.N) with an increase in concomitant over time while Ash (%), organic matter loss (%), CEC/TOC ratio, cellulose biodegradation ratio (BR) and lignin/cellulose ratio were significantly increased with time. By correlation study, biodegradability index (BI) and fluorescein diacetate (FDA) hydrolysis emerged as the most suitable compost maturity and stability parameters, respectively. Principal component analysis (PCA) results confirmed that BI, BR, WSC/Org. N and FDA can be regarded as key indicators for assessing compost quality. Our findings conclude that fungal consortia of Tricoderma viride, Rhizomucor pusillus, Aspergillus awamori and Aspergillus flavus can accelerate decomposition time from 8 to 12 months (which is normal farming practice) to 120 days.


Assuntos
Solo , Gerenciamento de Resíduos , Carbono , Fungos , Nitrogênio , Temperatura
20.
J Environ Manage ; 250: 109466, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31487602

RESUMO

Soil carbon (SC) is important for food security, ecosystem functioning, and environmental health, especially in light of global climate change. The physico-chemical character of biochar (pyrolyzed crop residue) has been shown to augment SC levels. This review systematically compares the environmental and economic benefits of applying crop residue versus biochar produced from crop residues to soils and the potential implications for SC sequestration. Crop residues enhance the mineralization rate of SC, while biochar can increase or decrease SC depending on the types of biochar/soil and duration. Therefore, converting crop residues to biochar may be more efficient for sequestering SC, but may/may not be more cost-effective. In this review, special emphasis is given to understanding the underlying mechanisms and biogeochemical processes of biochar production, in particular: surface (crystallinity), redox, and ability to control electron transfer reactions. By using meta-analytics, we determined the role of biochar compared to crop residue to enhance the status of organic SC.


Assuntos
Sequestro de Carbono , Solo , Agricultura , Carbono , Carvão Vegetal , Ecossistema
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