The Experts below are selected from a list of 34197 Experts worldwide ranked by ideXlab platform
R K Jones - One of the best experts on this subject based on the ideXlab platform.
-
the effect of previous Crop Residues and tillage on fusarium head blight of wheat
Plant Disease, 2000Co-Authors: Ruth Dillmacky, R K JonesAbstract:ABSTRACT Effects of previous Crop Residues and tillage practices on Fusarium head blight (FHB) of wheat were examined. Fusarium head blight was monitored in plots of the FHB-susceptible spring wheat cultivar Norm following Crops of corn, wheat, and soybeans in 1995, 1996, and 1997. Moldboard plow, chisel plow, and no-till treatments were imposed perpendicular to Crop strips to establish a range of residue levels in each of the previous Crop Residues. Fusarium head blight incidence and severity were greatest when wheat followed corn and least when wheat followed soybeans. Incidence and severity were lower in moldboard plowed plots than in either chisel plowed or no-till plots, although differences among chisel plow and no-till treatments were not apparent. Yields of wheat were approximately 15% lower in plots where wheat followed corn or wheat than in wheat following soybeans and were 10% greater in moldboard plowed plots than in either chisel plowed or no-till treatments. The deoxynivalenol (DON) content ...
-
the effect of previous Crop Residues and tillage on fusarium head blight of wheat
Plant Disease, 2000Co-Authors: Ruth Dillmacky, R K JonesAbstract:Effects of previous Crop Residues and tillage practices on Fusarium head blight (FHB) of wheat were examined. Fusarium head blight was monitored in plots of the FHB-susceptible spring wheat cultivar Norm following Crops of corn, wheat, and soybeans in 1995, 1996, and 1997. Moldboard plow, chisel plow, and no-till treatments were imposed perpendicular to Crop strips to establish a range of residue levels in each of the previous Crop Residues. Fusarium head blight incidence and severity were greatest when wheat followed corn and least when wheat followed soybeans. Incidence and severity were lower in moldboard plowed plots than in either chisel plowed or no-till plots, although differences among chisel plow and no-till treatments were not apparent. Yields of wheat were approximately 15% lower in plots where wheat followed corn or wheat than in wheat following soybeans and were 10% greater in moldboard plowed plots than in either chisel plowed or no-till treatments. The deoxynivalenol (DON) content of harvested grain was significantly correlated with FHB incidence and severity. The DON level in wheat following soybeans, averaged across tillage treatments, was 25% lower than in wheat following wheat and 50% of the level in wheat following corn. These findings suggest that changes in regional tillage practices, principally the move toward conservation tillage and reduced-till systems, contributed to the recent FHB epidemics in the Upper Midwest. Because differences in the type and quantity of Crop Residues in small plots affected disease development, it is likely that local sources of inoculum, such as those within a grower's field, contribute directly to the inoculum load and disease potential. The implication of these findings is that selection of cultural practices aimed to reduce inoculum-borne Residues will assist in the control of FHB.
Weixin Ding - One of the best experts on this subject based on the ideXlab platform.
-
manure over Crop Residues increases soil organic matter but decreases microbial necromass relative contribution in upland ultisols results of a 27 year field experiment
Soil Biology & Biochemistry, 2019Co-Authors: Yongxin Lin, Weijin Wang, Yakov Kuzyakov, Deyan Liu, Jiafa Luo, Stuart Lindsey, Jianbo Fan, Weixin DingAbstract:Abstract Organic fertilizers increase soil organic matter (SOM) stocks, but the underlying processes depend on the fertilizer type and remain largely unknown. To evaluate the predominant C stabilization mechanisms, upland Ultisols subjected to 27 years of mineral and organic fertilization were analyzed for SOM content, aggregate size classes, and amino sugar composition. The long-term field experiment had seven treatments: no fertilization (Control), mineral NPK fertilizers (NPK), NPK plus lime (NPK + Lime), NPK plus peanut straw (NPK + PeanutStraw), NPK plus rice straw (NPK + RiceStraw), NPK plus radish residue (NPK + RadishResidue), and NPK plus pig manure (NPK + PigManure). The 27-year application of mineral fertilizers (NPK and NPK + Lime), NPK + Crop Residues, and NPK + PigManure increased SOM content by 11.0–13.2%, 16.3–25.3%, and 44.3%, respectively, compared with the Control. The aliphaticity and recalcitrance indices based on 13C nuclear magnetic resonance spectra of organic fertilizers were higher for pig manure than for Crop Residues. Both indices were closely correlated with SOM content after 27 years, so higher proportions of recalcitrant C in manure facilitated SOM accumulation. NPK + PigManure increased the mass proportion of large macroaggregates 2.9-fold compared with the Control, and reduced the effective diffusion coefficient of oxygen in the soil. Consequently, NPK + PigManure limited the activity and abundance of aerobes and the accessibility of SOM to microorganisms, in turn facilitating SOM accumulation. The application of mineral fertilizers, NPK + Crop Residues, and NPK + PigManure increased microbial necromass to 2.85–3.03, 3.21–3.45, and 3.62 g C kg−1, respectively, from 2.63 g C kg−1 in the Control. Compared with Crop Residues, pig manure did not affect bacterial necromass but increased fungal necromass from 2.19 to 2.39 g C kg−1 to 2.58 g C kg−1, which might associate with increased SOM stability. However, the relative contribution of microbial necromass to SOM was lower under NPK + PigManure than under NPK + Crop Residues, since more added C was protected in the NPK + PigManure soil. Our results suggest that manure may contribute to SOM accumulation and stabilization in three ways: directly through the input of recalcitrant organic C, indirectly through the stabilization of aggregates and physical protection of C, and to a lesser extent through increasing fungal necromass.
-
dominant effects of organic carbon chemistry on decomposition dynamics of Crop Residues in a mollisol
Soil Biology & Biochemistry, 2017Co-Authors: Zengming Chen, Jiafa Luo, Sebastien Fontaine, Wenqing Wang, Jianling Fan, Weixin DingAbstract:Abstract Understanding the change in chemical composition of Crop Residues during their decomposition is crucial to elucidate the mechanisms underlying the effects of residue retention on soil carbon (C) sequestration and nutrient cycling. Here a field experiment was carried out to investigate the decomposition process of maize, soybean, and wheat Residues in a cultivated Mollisol in northeast China over a year. Using a litterbag method, we monitored the dynamics of residue mass loss, concentration of C and nitrogen (N), and C/N ratio, and evaluated the decomposition rates of Residues and C functional groups. Chemical compositions of the Crop Residues were determined by solid-state 13 C nuclear magnetic resonance spectroscopy, and the cellulose crystallinity, lignin concentration, and syringyl to guaiacyl (S/G) ratio of lignin were estimated. After one year of incubation in field conditions, mass loss was 57% for soybean Residues, significantly greater than 52% for maize and 45% for wheat. The decomposition rate of Residues significantly decreased from 0.223 to 0.379 month −1 during the first month to 0.054–0.076 month −1 over the whole period. The proportion of decomposed C ranged at 57–63% among different Residues, and had a positive relationship with the mass loss of O-alkyl C, di- O -alkyl C, and carbonyl C. The decomposition rates of these three C functional groups were greater in soybean than those in maize and wheat Residues, which was also the case for lignin S/G ratio, possibly accounting for the higher decomposition extent of soybean Residues. As decomposition progressed, the C chemistry of maize, soybean, and wheat Residues exhibited an increasing divergence, which was mainly related to relative decreases in O-alkyl C and di- O -alkyl C contents, and relative increases in phenolic C and aromatic C contents in the Residues. Net N release was observed for all Residues after one-year decomposition, and was significantly related to the mass loss of alkyl C, O-alkyl C, and aromatic C. Overall, our study provides insight into chemical changes of Crop Residues over the degradation processes in the field, and highlights the significant effects of organic C chemistry on residue decomposition.
Ruth Dillmacky - One of the best experts on this subject based on the ideXlab platform.
-
the effect of previous Crop Residues and tillage on fusarium head blight of wheat
Plant Disease, 2000Co-Authors: Ruth Dillmacky, R K JonesAbstract:ABSTRACT Effects of previous Crop Residues and tillage practices on Fusarium head blight (FHB) of wheat were examined. Fusarium head blight was monitored in plots of the FHB-susceptible spring wheat cultivar Norm following Crops of corn, wheat, and soybeans in 1995, 1996, and 1997. Moldboard plow, chisel plow, and no-till treatments were imposed perpendicular to Crop strips to establish a range of residue levels in each of the previous Crop Residues. Fusarium head blight incidence and severity were greatest when wheat followed corn and least when wheat followed soybeans. Incidence and severity were lower in moldboard plowed plots than in either chisel plowed or no-till plots, although differences among chisel plow and no-till treatments were not apparent. Yields of wheat were approximately 15% lower in plots where wheat followed corn or wheat than in wheat following soybeans and were 10% greater in moldboard plowed plots than in either chisel plowed or no-till treatments. The deoxynivalenol (DON) content ...
-
the effect of previous Crop Residues and tillage on fusarium head blight of wheat
Plant Disease, 2000Co-Authors: Ruth Dillmacky, R K JonesAbstract:Effects of previous Crop Residues and tillage practices on Fusarium head blight (FHB) of wheat were examined. Fusarium head blight was monitored in plots of the FHB-susceptible spring wheat cultivar Norm following Crops of corn, wheat, and soybeans in 1995, 1996, and 1997. Moldboard plow, chisel plow, and no-till treatments were imposed perpendicular to Crop strips to establish a range of residue levels in each of the previous Crop Residues. Fusarium head blight incidence and severity were greatest when wheat followed corn and least when wheat followed soybeans. Incidence and severity were lower in moldboard plowed plots than in either chisel plowed or no-till plots, although differences among chisel plow and no-till treatments were not apparent. Yields of wheat were approximately 15% lower in plots where wheat followed corn or wheat than in wheat following soybeans and were 10% greater in moldboard plowed plots than in either chisel plowed or no-till treatments. The deoxynivalenol (DON) content of harvested grain was significantly correlated with FHB incidence and severity. The DON level in wheat following soybeans, averaged across tillage treatments, was 25% lower than in wheat following wheat and 50% of the level in wheat following corn. These findings suggest that changes in regional tillage practices, principally the move toward conservation tillage and reduced-till systems, contributed to the recent FHB epidemics in the Upper Midwest. Because differences in the type and quantity of Crop Residues in small plots affected disease development, it is likely that local sources of inoculum, such as those within a grower's field, contribute directly to the inoculum load and disease potential. The implication of these findings is that selection of cultural practices aimed to reduce inoculum-borne Residues will assist in the control of FHB.
Jeanfrancois Dallemand - One of the best experts on this subject based on the ideXlab platform.
-
optimal energy use of agricultural Crop Residues preserving soil organic carbon stocks in europe
Renewable & Sustainable Energy Reviews, 2015Co-Authors: F Monforti, Nicolae Scarlat, Katalin Bodis, Emanuele Lugato, Vincenzo Motola, Jeanfrancois DallemandAbstract:Abstract The European Union has committed itself to ambitious targets of Renewable Energy and bioenergy is expected to play a major role, increasing its contribution to Gross Final Energy Consumption from 2458 PJ in 2005 to 4605 PJ by 2020. Agricultural Crop Residues are considered a reliable resource for energy uses but important concerns still exist on the potential depletion of Soil Organic Carbon (SOC) stocks that may partially offset the environmental suitability and convenience of their large-scale exploitation. This paper provides an estimate of available agricultural Residues and related potential energy production obtainable without impacting the EU SOC stock showing how SOC content preservation imposes the application of different collection rates for agricultural Residues across the EU, depending on factors such as climate, soil type, current farming practices and pre-existing cultivation history. The results suggest that a potential amount of Residues of 146,000 kt/year of dry matter leading to a potential gross energy production of about 2300 PJ/year could be obtained in EU-27 1 without impacting the current SOC stocks. Agricultural Residues are then theoretically able to provide a substantial contribution to renewable energy targets in several EU-27 countries as well as accommodating competitive uses and SOC preservation. Nevertheless, the spatial pattern of results also clearly indicates regions and countries where Residues exploitation should be handled with care and current practices on Residues collection are risky in term of SOC content. The estimate provided builds on results from previous studies (e.g., Scarlat et al. Waste Manage 2010;30:1889–1897, Monforti et al. Renewable Sustainable Energy Rev 2013;19:666–677) and on the analysis of future scenarios of SOC content obtained from an innovative pan-EU modelling platform (Lugato et al. Global Change Biol 2014;20:313–326. doi:10.1111/gcb.12292. Such an integrated approach, making use of soil, climate and energy transformation modelling, is unique and constitutes a substantial applied value for assessing the sustainability of Crop Residues use.
-
the possible contribution of agricultural Crop Residues to renewable energy targets in europe a spatially explicit study
Renewable & Sustainable Energy Reviews, 2013Co-Authors: F Monforti, Nicolae Scarlat, Katalin Bodis, Jeanfrancois DallemandAbstract:Abstract This paper provides a geographical assessment of potential bioenergy production in the European Union from Residues of eight agricultural Crops (wheat, barley, rye, oat, maize, rice, rapeseed and sunflower). The evaluation is geographically explicit at the scale of 1 km2 and is based on two main computational steps. In the first step the amount of Crop Residues resulting from statistical assessment based on the methodology developed by Scarlat et al. [1] have been spatially allocated on the EU-27 1 territory using several auxiliary geospatial layers describing, for example, land cover, expected biomass productivity derived from soil parameters, climatic zones and topographical conditions. In the second step the number of model power plants (i.e., plants with a size of 50 MW thermal input and a raw material demand of about 100 kt/yr might be conveniently fed with available Crop Residues was estimated on the basis of two different allocation strategies implying a different grade of optimization. The results show that the estimated Crop residue resources in EU-27 could provide fuel for about 850 plants expected to produce about 1500 PJ/yr. Mobilization needs for the Residues are also estimated, leading to a total amount of 1.5×1012–2×1012 tkm are necessary for the full potential exploitation.
-
assessment of the availability of agricultural Crop Residues in the european union potential and limitations for bioenergy use
Waste Management, 2010Co-Authors: Nicolae Scarlat, Milan Martinov, Jeanfrancois DallemandAbstract:This paper provides a resource-based assessment of the available agricultural Crop Residues for bioenergy production in the European Union, at the level of the 27 Member States. The assessment provides the amount of the Residues produced, collected, their present uses and the Residues left available for bioenergy. This study considers the Crop production and yields and multi-annual yield variation for each Crop. The calculation was based on specific Residues to product ratios, which were determined, depending on the Crop type and Crop yield. Sustainable removal rates were considered in order to protect soil fertility. The results show large spatial and temporal variations of available Crop Residues within EU27. The average amount of Crop Residues available for bioenergy in EU27 was estimated at 1530 PJ/year, with a variation between 1090 and 1900 PJ/year. The average value represents about 3.2% in final energy consumption in the EU27 while the variation 2.3-4%. This variation, which is even larger at the level of Member States, may result in shortages in biomass supply in some years, when Crop Residues are available in a lower amount than the average.
K M Goh - One of the best experts on this subject based on the ideXlab platform.
-
nitrogen release from Crop Residues and organic amendments as affected by biochemical composition
Communications in Soil Science and Plant Analysis, 2003Co-Authors: Kuldip Kumar, K M GohAbstract:Although amounts and patterns of nitrogen mineralization from decomposing Crop Residues and other organic materials are known to be affected by their initial chemical composition and quality (e.g., C/N ratio, lignin and soluble polyphenol concentrations), published results differed in which properties correlated best with the N release. Six Crop Residues (leguminous and non-leguminous) and two organic materials (spent mushroom compost and dairy pond sludge) were incubated to determine the release of mineral N and its relationships to residue chemical composition. A previously proposed equation for calculating plant residue quality index (PRQI) was modified to PRQIM (Plant residue quality index-modified) to include C/N, lignin/N and polyphenol/N ratios of Crop Residues and organic materials so as to integrate these three major variables, which control the residue decomposition and nutrient release. The PRQIM was significantly and highly correlated with N release not only for the data obtained in the present study but also for three independent data sets obtained from the literature for a wide variety of organic materials ranging from arable Crop Residues, tropical savanna woodland litter and leguminous tree prunings.
-
Crop Residues and management practices effects on soil quality soil nitrogen dynamics Crop yield and nitrogen recovery
Advances in Agronomy, 1999Co-Authors: K Kumar, K M GohAbstract:This review reveals that Crop Residues of common cultivated Crops are an important resource not only as a source of significant quantities of nutrients for Crop production but also affecting soil physical, chemical, and biological functions and properties and water and soil quality. When Crop Residues are returned to the soils, their decomposition can have both positive and negative effects on Crop production and the environment. Our aim as agricultural scientists is to increase the positive effects. This can only be achieved with the better understanding of residue, soil, and management factors and their interactions, which affect the decomposition and nutrient release processes. Data on nitrogen benefits and nitrogen recoveries from Residues show that a considerable potential exists from Residues, especially leguminous Residues, not only in meeting the N demands of the succeeding Crops, but also in increasing the long-term fertility of the soils. In addition, Crop Residues and their proper management affects the soil quality either directly or indirectly. Intensive Cropping systems are very diverse and complex, so no one residue management system is superior under all situations. Ideally, Crop residue management practices should be selected to enhance Crop yields with a minimum adverse effect on the environment. It is suggested that in each Cropping system, the constraints to production and sustainability should be identified and conceptualized to guide toward the best option. Multidisciplinary and integrated efforts by soil scientists, agronomists, ecologists, environmentalists, and economists are needed to design a system approach for the best choice of Crop residue management system to enhance both agricultural productivity and sustainability.