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Jianbo SHEN Qichao ZHU Xiaoqiang JIAO Hao YING Hongliang WANG Xin WEN Wen XU Tingyu LI Wenfeng CONG Xuejun LIU Yong HOU Zhenling CUI Oene OENEMA William J. DAVIES Fusuo ZHANG 《农业科学与工程前沿(英文版)》2020,7(1):5-13
Realizing sustainable development has become a global priority. This holds, in particular, for agriculture. Recently, the United Nations launched the Sustainable Development Goals (SDGs), and the Nineteenth National People’s Congress has delivered a national strategy for sustainable development in China—realizing green development. The overall objective of Agriculture Green Development (AGD) is to coordinate “green” with “development” to realize the transformation of current agriculture with high resource consumption and high environmental costs into a green agriculture and countryside with high productivity, high resource use efficiency and low environmental impact. This is a formidable task, requiring joint efforts of government, farmers, industry, educators and researchers. The innovative concept for AGD will focus on reconstructing the whole crop-animal production and food production-consumption system, with the emphasis on high thresholds for environmental standards and food quality as well as enhanced human well-being. This paper addresses the significance, challenges, framework, pathways and potential solutions for realizing AGD in China, and highlights the potential changes that will lead to a more sustainable agriculture in the future. Proposals include interdisciplinary innovations, whole food chain improvement and regional solutions. The implementation of AGD in China will provide important implications for the countries in developmental transition, and contribute to global sustainable development. 相似文献
2.
Biogeochemical processes describing nutrient cycling strongly affect the development of different soil horizons and soil acidification. However, in many soil acidification models these processes are not directly simulated, and spatially distributed soil properties are lumped into average values. This paper describes the extension of a one-layer soil acidification model (SMART) to a multi-layer model (SMARTEX) by including nutrient cycling, and the performance of both models regarding their ability for the assessment of the effects of acid deposition on forest soil. This was done by comparing simulation results of the two models with respect to changes in base cation amounts to historical data from sites in south Sweden. The results showed that the multi-layer model gives better results for the top soil, whereas the one-layer model gives better results for the rootzone and the total profile. Since the top soil is most important, the extended model is more suited to relate acid deposition to forest growth than the more general results of the one-layer model. However, the sensitivity of the multi-layer model to some parameters is large. A change in these parameters had strong effects on the separate layers, whereas the effects were cancelled out over the total profile. This sensitivity requires a careful parameterization of the model which might be troublesome to lack of data. 相似文献
3.
A. M. Anithakumari Oene Dolstra Ben Vosman Richard G. F. Visser C. Gerard van der Linden 《Euphytica》2011,181(3):357-369
Drought stress is a major abiotic constraint limiting crop production worldwide. Screening for drought tolerance and the traits
that enhance drought tolerance is not straightforward in large mapping populations. In this study, we investigated the possibility
of screening a mapping population in vitro for PEG-induced water deficit stress and recovery potential. We have measured several
shoot and root growth parameters or traits in the C × E diploid potato mapping population. Significant variation was observed
for genotype-specific responses to water deficit and recovery potential. Genetic variation and heritability estimates were
high to very high for the measured traits depending on growth conditions. In order to identify potato QTLs for drought tolerance
and recovery potential an SNP marker-rich integrated linkage map was used. A total of 23 QTLs were detected under control,
stress and recovery treatments explaining 10.3–22.4% of the variance for each phenotypic trait. Among these, 10 QTLs were
located on chromosome 2. Three QTLs involved in the important trait root to shoot ratio were identified on linkage groups
2, 3 and 8. These loci explained together 41.1% of the variance for this trait, and may be breeding targets for stress tolerance
and yield in the field as well. The SNP markers derived from EST sequences underlying these QTLs led to the identification
of putative candidate genes for further study in potato. This study constitutes the first knowledge of in vitro screening
of a mapping population for drought tolerance in potato. 相似文献
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Growth and photosynthetic performance were analyzed in alloplasmic tomato at a high- (25/17 °C; HTR) and low-temperature regime (12/6 °C; LTR) in order to establish the role of cytoplasmic variation on low-temperature tolerance of tomato (Lycopersicon esculentum Mill.). Four alloplasmic tomato lines, containing the nuclear genome of tomato and the plastome of L. hirsutum LA 1777 Humb. & Bonpl., an accession collected at high-altitude in Peru, were reciprocally crossed with 11 tomato entries
with a high inbreeding level and a wide genetic variation, resulting in a set of 44 reciprocal crosses. Irrespective of growth
temperature, alloplasmic families with alien chloroplasts of L. hirsutum (h) were on average characterized by a high shoot biomass, a large leaf area, and a low specific leaf area in comparison with
their euplasmic counterparts. These results do not directly point to an advantageous effect of h-chloroplasts on biomass accumulation at low temperature but rather towards a small general beneficial effect on growth and/or
distribution of assimilates. Significant chloroplast-related differences in photosynthetic performance, however, were not
detected at both temperature regimes, indicating that h-chloroplasts can properly function in a variable nuclear background of L. esculentum. It is concluded that chloroplast substitution is not an effective method for breeding tomato plants with improved low-temperature
tolerance.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
6.
Nitrous oxide fluxes from grassland in the Netherlands: I. Statistical analysis of flux-chamber measurements 总被引:2,自引:0,他引:2
Accurate estimates of total nitrous oxide (N2O) losses from grasslands derived from flux-chamber measurements are hampered by the large spatial and temporal variability of N2O fluxes from these sites. In this study, four methods for the calculation of mean N2O fluxes (n= 6) on total N2O losses are compared, namely the arithmetic mean, the geometric mean, the lognormal mean and the mean derived from Finney's method. Mean fluxes were calculated from weekly flux measurements on grassland at four contrasting sites in the Netherlands with three management treatments each. Total losses were calculated by interpolation of the mean fluxes and integration over time. Spatial variation of N2O fluxes was large. The geometric mean was generally much smaller, up to a factor of 7, than the arithmetic mean. The lognormal mean was much larger, up to a factor of 11, than the arithmetic mean, possibly because this estimator is biased for small sample size. Arithmetic means and Finney's method were generally in reasonable agreement. The order in estimated N2O loss increased in the order geometric meann = 6), the uncertainty about the precise frequency distribution, the sensitivity of estimators based on logtransformed data, and the problems associated with negative fluxes, the arithmetic mean was preferred as the most appropriate estimator. Evidently, the choice of an estimator of the mean can have great effects on the estimation of total N2O losses. 相似文献
7.
耕作、残茬及施肥管理对土壤有机质动态变化影响的情景分析 总被引:7,自引:0,他引:7
Based on data from 10-year field experiments on residue/fertilizer management in the dryland farming region of northern China, Century model was used to simulate the site-specific ecosystem dynamics through adjustment of the model's parameters, and the applicability of the model to propose soil organic carbon (SOC) management temporally and spatially, in cases such as of tillage/residue/fertilization management options, was identified v/a scenario analysis.Results between simulations and actual measurements were in close agreement when appropriate applications of stover,manure and inorganic fertilizer were combined. Simulations of extreme C/N ratios with added organic materials tended to underestimate the measured effects. Scenarios of changed tillage methods, residue practices and fertilization options showed potential to maintain and enhance SOC in the long run, while increasing inorganic N slowed down the SOC turnover rate but did not create a net C sink without any organic C input. The Century model simulation showed a good relationship between annual C inputs to the soil and the rate of C sequestration in the top 20 cm layer and provided quantitative estimations of changes in parameters crucial for sustainable land use and management. Conservation tillage practices for sustainable land use should be integrated with residue management and appreciable organic and inorganic fertilizer application, adapted according to the local residue resource, soil fertility and production conditions. At least 50% residue return into the soil was needed annually for maintenance of SOC balance, and manure amendment was important for enhancement of SOC in small crop-livestock systems in which crop residue land application was limited. 相似文献
8.
Zifu Yan Oene Dolstra Theo W. Prins Piet Stam Peter B. Visser 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(3):301-308
Powdery mildew (Podosphaera pannosa) is the most important fungal disease in greenhouse roses and is in practice controlled by fungicides. The creation of novel
cultivars with durable resistance to powdery mildew is highly desirable. To understand the inheritance of mildew resistance,
a tetraploid rose population with a size of 181 seedlings was obtained by crossing two tetraploid genotypes each having partial
resistance. The population and its parents were tested under greenhouse conditions with two well-defined monospore isolates
(2 and F1) using artificial inoculation with spore suspensions. Disease score at 11 days post-inoculation, latent period and
rate of symptom development were used to describe seedling resistance. The tests for both isolates exhibited a wide and significant
variation among genotypes for resistance. The distribution of the genotypic means of the disease scores was continuous and
showed a considerable transgression. Statistical analysis, scatter plot of disease scores for the isolates, and correlation
analyses indicated that the two isolates differed in pathogenicity. The outcome of the tests showed that the inoculation assay
with spore suspensions was a reliable and effective way to screen large numbers of genotypes under greenhouse conditions for
genetic and breeding studies. This is the first report on spore-suspension inoculation to be used successfully in rose. 相似文献
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Interpretation of the oxygen isotopic signature of soil-derived N2O may be flawed when it is based on reaction stoichiometry and fractionation alone. In fact, oxygen (O) exchange between H2O and intermediates of N2O production pathways may largely determine this O isotopic signature. Although in our previous work we conclusively proved the occurrence of O exchange during N2O production by denitrification of NO3−, its occurrence in N2O production pathways by nitrifiers remains unclear. The aim of this study was to examine the likeliness of O exchange during various stages of N2O production in soil via nitrification, nitrifier denitrification and denitrification. We evaluated a set of scenarios on the presence of such exchange using data from a series of 18O and 15N tracing experiments. The measured actual O incorporation from H2O into N2O (AOI) was compared with the theoretical maximum O incorporation (MOI) from various scenarios that differed in their assumptions on the presence of O exchange. We found that scenarios where O exchange was assumed to occur exclusively during denitrification could not explain the observed AOI, as it exceeded the MOI for 9 out of 10 soils. This demonstrates that additional O exchange must have occurred in N2O production through nitrifier pathways. It remains to be determined in which steps of these pathways O exchange can take place. We conclude that O exchange is likely to be mediated by ammonia oxidizers during NO2− reduction (nitrifier denitrification), and that it could possibly occur during NO2− oxidation to NO3− by nitrite oxidizers as well. 相似文献