Supervisor(s): Ministry of Agriculture Sponsor(s): Chinese Academy of Agricultural Sciences；Chinese Association of Agricultural Science Societies CN：11-1328/S
Scientia Agricultura Sinica, the 1st in Comprehensive Agricultural Science, is supervised by Ministry of Agriculture of PRC, and sponsored by Chinese Academy of Agricultural Sciences; Chinese Association of Agricultural Science Societies. Scientia Agricultura Sinica, launched in 1960, is a leading peer-reviewed and mufti-disciplinary journal and published semi-monthly in Chinese with English title, abstract, figures, tables and references. It aims to publish those papers that are influential and will significantly advance scientific understanding in agriculture fields worldwide. The scope covers Crop Genetics, Breeding, Germplasm Resources; Physiology, Biochemistry, Cultivation, Tillage Plant Protection; Soil & Fertilization, Agro-Ecology & Environment, Bio-energy; Animal Science, Veterinary Science, Agricultural Information Science; Food Science; Agricultural Economics and Management; Agricultural Sustainability.
The journal is included in JST, CA and CSCD.
Editor-in-Chief Wan Jianmin Associate Editor-in-Chief Zou Ruicang Tang HuaJun Wu Kongming Guo YuYuan Geng Xu Sun Tan Executive Editor Lu Wenru
The introduction of Clementsian succession theory in the early twentieth century represented a substantial advance in rangeland ecology. Succession theory as a central concept of equilibrium ecology had profound influence on development of rangeland science and natural resource management models. However, the equilibrium ecology and the steady-state management model received severe criticism in the 1970s and 1980s. On one hand, nonlinear vegetation dynamics was recognized in rangeland ecosystem research, which was inconsistent with the interpretation of the traditional succession and steady-state management. On the other hand, the research in other parts of the world indicated that the rangeland concepts and range models developed in the United States did not well apply to the ecosystems in Africa and Asia where the prevailing environments were characterized by frequent disturbance and alternative conceptual frameworks awere called for to provide more realistic, accurate interpretations of range vegetation dynamics and scientific support to natural resource management. In this context, equilibrium ecology emerged in response to the dissatisfaction of the prevailing ecological theory. In particular, an ecosystem-level research in east Africa presentsed a view of pastoral ecosystems that were nonequilibrial but persistent (persistent nonequilibrium model), and further research resulted in the recognition of the importance of relative proportion of key resource in the dry/cold season as the determinant of animal numbers and their potential impacts on vegetation. The state-and-transition model which emerged in the 1980s represented an important alternative conceptual framework and was applied in the 1990s to rangeland assessment as a replacement of range condition in the USA. Resilience is currently replacing nonequilibrium as the dominant ecological concept because ecosystems that were previously considered nonequilibrium is now more appropriately interpreted as multiple equilibria in many cases. The advances in rangeland ecological theory have been accompanied by parallel progression of rangeland management model, notably a transformation of the role of human from resource user to resource steward. The rangeland models in the twentieth century were generalized as steady-state management with the overall goal of maximizing sustainable production of forage and livestock. The application of resilience as the most recent and important ecological advance has been extended to coupled social-ecological systems, leading to the development of the concept and procedures of adaptive management. Currently, the above described models are in application to a greater or less extent and synthesis of different models for rangeland assessment and management will help develop improved framework for complex and adaptive social-ecological systems.
[Objective] Application of organic manure can promote soil microorganisms growth and improve soil fertility. However, very rare studies were conducted to quantify the effects of manure application on soil microbial biomass carbon (SMBC) and nitrogen (SMBN) in croplands at national scale. Therefore, quantifying the effects of manure application on the contents of SMBC and SMBN under different climatic regions and soil conditions is important to provide the theoretical basis for reasonably applying manure, so as to enhance soil fertility and microbial activities for China’s croplands. [Method] In the current study, all of 70 articles, including the impacts of manure application on the contents of SMBC and SMBN in croplands in China between 1990 and 2017, were collected (336 data for SMBC and 222 data for SMBN). The meta-analysis was used to quantify the magnitude of manure application impacts on the contents of SMBC and SMBN at three aspects: Climatic regions, land use types, and soil pH levels. [Result] At the national scale, the contents of SMBC and SMBN in manure applied soils significantly increased by 128.1% and 70.2% when compared with no fertilizer (CK), respectively, while those increased by 57.1% and 34.2% when compared with mineral fertilizer (NPK), respectively. The increments of SMBC and SMBN contents improved by manure compared with NPK in subtropical monsoon climatic region (66.7% and 57.5%, respectively) were significantly higher than those in temperate continental climatic region (26.0% and 20.9%, respectively) and temperate monsoon climatic region (37.0% and 56.7%, respectively). Furthermore, manure application could significantly increase the contents of SMBC and SMBN in paddy soils (69.1% and 67.1%, respectively) compared with NPK, which were higher than those in upland (34.7% and 26.4%, respectively) and upland-paddy soils (50.2% and 63.9%, respectively). For the neutral soils (6 < pH < 8), the increments of SMBC and SMBN contents by 64.4% and 63.7% in the treatment with manure application compared with NPK were higher than those in the alkaline (pH > 8, 29.4% and 21.9%) and acidic soils (pH < 6, 44.4% and 45.5%). In addition, the correlation analysis showed that the contents of SMBC and SMBN were positively correlated with annual carbon and nitrogen input from manure, respectively. [Conclusion] Overall, the application of manure can dramatically improve the contents of SMBC and SMBN, indicating manure supplementation provides sufficient carbon and nitrogen for microbial growth and reproduction as well as nutrient retention. Nevertheless, the effects of manure application on the contents of SMBC and SMBN relative to CK and NPK were significantly different among climatic regions, land use types, and soil pH levels. Therefore, climate types and soil conditions should be taken into consideration for applying manure in different regions in China.
[Objective] Plastic mulching after seeding followed by artificial transplantation of seedlings at full emergence (seeding before mulching, SBM) is widely adopted in the Yellow River valley, but it is labor-intensive and costly. Plastic mulching in advance and seeding on plastic film (seeding after mulching, SAM) can remove the process of seedling transplantation and has been widely applied in the the inland cotton region in Northwest China, but its application in the cotton region in Yellow River valley depends on the influence of rainfall at emergence on stand establishment. The objective of this study is to determine the effect of rainfall at emergence on stand establishment and yield of cottonunder different seeding patterns, and to determine a simple and appropriate seeding pattern for cotton in the Yellow River valley. [Method] A two-year field experiment was conducted to evaluate the effect of rainfall and seeding pattern on stand establishment, leaf area index, yield and yield components. A split-plot design with three replicates was used for the study, with the simulated rainfalls (0 mm and 10 mm) as the main plotand seeding patterns of seeding without mulching (SWM), SBM, SAM and seeding under double mulching (SDM) as the subplot. [Result] Significant interaction was detected between rainfall and seeding pattern on emergence rate, dry matter accumulation, leaf area index, boll density and cotton yield. Without rainfall, the emergence rate, dry matter, leaf area index, boll density and yield of SAM and SDM were similar to those of SBM, but those of SWM were reduced by 13.6%, 19.0%, 13.3%, 24.7% and 27.7% compared wth SBM, respectively. Under 10 mm rainfall, these parameters were decreased by 32.2%, 43.1%, 26.3%, 25.8% and 29.2% for SAM, respectively, and 42.8%, 55.8%, 47.2%, 35.0% and 40.1% for SWM, respectively, as compared with SBM, but all the parameters of SDM were similar to those of SBM. [Conclusion] SAM reduced stand establishment and cotton yield compared with SBM under 10 mm rainfall, but SDW exhibited comparable stand establishment and yield compared with SBM regardless of rainfall. Therefore, choosing a suitable seeding pattern is an important way to guarantee full stand establishment and high yield in terms of local ecological conditions, especially the rainfall probability.
[Objective] The objective of this study was to explicit the effects of inherent soil productivity and different fertilizer measures on maize (
Zea mays L.) yield in southwest China, so as to provide scientific basis for improving soil fertility and proper fertilization of the maize belt in southwest China. [Method] Based on 508 maize field trials in southwest China since 2006, we chosen 5 treatments, including non-fertilizing control (CK), nitrogen and phosphate (NP) fertilizer, nitrogen and potassium (NK) fertilizer, phosphate and potassium (PK) fertilizer, and NPK fertilizer (NPK), to measure maize yield and nutrient absorption, and to analyze the yield, soil and contribution characteristics of inherent soil productivity, as well as yield response and agronomic efficiency. And we evaluated the relationship between the soil foundation and maize yield (or yield gap) by using the line fitting and boundary line method, and assessed the effect of the soil foundation on the stability and sustainability of fertilizer-induced yield by using the stability index and the sustainability index in the maize planting area. [Result] The maize yield based on inherent soil productivity in the southwest region ranged from 3.9 to 4.7 t·hm
−2 (average: 4.4 t·hm
−2). Fertilization could significantly increase the maize yield. The average yield in the fertilizer (NPK) application area was 7.7 t·hm
−2, which increased 3.3 t·hm
−2 than the yield based on the inherent soil productivity. The results based on the boundary analysis showed that the high yield potential was 11.5, 12.7, 12.6 t·hm
−2 (average: 11.7 t·hm
−2) in Chongqing, Sichuan and Guizhou, respectively. The contribution rates of maize yield and fertilizer contribution averaged 57. 1% and 42.9%, respectively; the contribution rate of soil productivity increases with the increase yield based on inherent soil productivity. The effects of fertilizers on the increase of maize yield from high to low were as followed: the nitrogen fertilizer > phosphate fertilizer > potassium fertilizer in southwest China. The fitting line decision coefficient between maize realistic productivity and inherent soil productivity in Chongqing, Sichuan, Guizhou and the entire southwest was 0.356, 0.356, 0.393 and 0.434 (
P < 0.001), respectively. And with the increase of inherent soil productivity, the fertilizer-induced yield gap decreased, whereas the stability and sustainability of the yield increased. [Conclusion] Improving inherent soil productivity could increase the maize yield and increase the stability and sustainability of the yield, reduce the dependence of maize on fertilizer, and promote the high and stable yield of maize in the southwest China.
[Objective] If herbicide-resistant transgenes escape from transgenic oilseed rape (
Brassica napus, AACC, 2n = 38) to their weedy relatives through pollen flow, the weeds with the herbicide-resistant trait might produce new problems for weed control. Wild
B. juncea (AABB, 2n = 36), relative weed of transgenic
B. napus, has become a major weed of crop systems across western China, and extended eastward along the Yangtze River Valley. In order to provide experimental data for whether the transgene can successfully escape to wild
B. juncea, it is necessary to evaluate the fitness of backcross progenies between herbicide-resistant transgenic
B. napus and wild
B. juncea before it is released. [Method] Wild
B. juncea and herbicide-resistant BC
3mF
4R, BC
3pF
4R and BC
3m F
4L, BC
3pF4L (R and L denote glyphosate- and glufosinate-resistant backcross progenies obtained with glyphosate- and glufosinate-resistant transgenic
B. napus, respectively. m and p denote backcross progeny obtained with wild
B. juncea as maternal plants and paternal plants, respectively) were planted at low (15 plants per plot) and high density (30 plants per plot) in pure and mixed stands (wild
B. juncea:backcross progenies were 4:1, 3:2 and 1:1). The vegetative components (plant height, stem diameter, the first branch number/plant, above-ground dry biomass/plant) and reproductive components (silique number/plant, total seed weight/plant, silique length, seed number/silique) of these backcross progenies were measured. The difference of the composite fitness between BC
3F
4 and wild
B. juncea was analyzed. [Result] Under pure stands, there was no significant difference in the fitness components and composite fitness of BC
3F
4R with that of wild
B. juncea. The composite fitness of BC
3F
4L was also similar to wild
B. juncea although the stem diameter, above-ground dry biomass/plant, and silique number/plant of BC
3F
4L at high density were significantly lower than those of wild
B. juncea. Therefore, either glyphosate-or glufosinate-resistant BC
3F
4 was as fit as wild
B. juncea regardless of density under pure stands. Under mixed stands, at low density, there was no significant difference in the composite fitness of glyphosate- or glufosinate-resistant BC
3F
4 with that of wild
B. juncea. At high density, there was no significant difference in fitness components and composite fitness of BC
3F
4R with that of wild
B. juncea regardless planting ratios. However, the plant height, stem diameter, the first branch number/plant, above-ground dry biomass/plant, silique number/plant, total seed weight/plant and composite fitness of BC
3F
4L were significantly lower than those of wild
B. juncea. The correlation analysis showed that the fitness components of BC
3F
4 were only related to the planting density. [Conclusion] The glyphosate- or glufosinate-resistant BC
3F
4 between glyphosate-or glufosinate-resistant transgenic
B. napus and wild
B. juncea have a strong survival ability and potential possibility of establishing populations in the field. Moreover, the ecological risk of gene flow is higher from the glyphosate-resistant transgenic
B. napus than the glufosinate-resistant transgenic
B. napus. Therefore, the gene escape from the herbicide-resistant
B. napus to wild
B. juncea should only be prevented in their initial hybrids, and the backcross between wild
B. juncea and F
1 or subsequent generations should also be prevented, so as not to produce higher fitness backcross progenies.
