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    Overview of Impacts of Climate Change and Adaptation in China’s Agriculture
    WANG Jin-xia, HUANG Ji-kun , YANG Jun
    2014, 13(1): 1-17.  DOI: 10.1016/S2095-3119(13)60588-2
    Abstract ( )   PDF in ScienceDirect  
    The purpose of this paper is to document the likely impacts of climate change on China’s agriculture and the current adaptation efforts made by government and farmers. The review of literature shows that climate change will have a significant impact on agriculture, primarily through its effect on crop yields. The extent of predicted impacts highly depends on the crop, the CO2 fertilization effect assumption and adaptation abilities. Market response to the production shocks resulting from climate change will lessen the impacts on agricultural production predicted by natural scientists. On adaptation, the government’s major efforts have been in the developing new technologies, reforming extension system and enhancing institutional capacity. Farmers do adapt to climate change, but their adaptation measures cannot fully offset the negative impacts of climate change. The paper concludes and makes implications for future studies.
    Crop Genetics · Breeding · Germplasm Resources
    Effect of Environment and Genetic Recombination on Subspecies and Economic Trait Differentiation in the F2 and F3 Generations from indicajaponica Hybridization
    WANG He-tong, JIN Feng, JIANG Yi-jun, LIN Qing-shan, XU Hai, CHENG Ling, XIA Ying-jun, LIU Chun-xiang, CHEN Wen-fu , XU Zheng-jin
    2014, 13(1): 18-30.  DOI: 10.1016/S2095-3119(13)60353-6
    Abstract ( )   PDF in ScienceDirect  
    indica and japonica are the two most important subspecies of Asian cultivated rice. Identifying mechanisms responsible for population differentiation in these subspecies is important for indica-japonica hybridization breeding. In this study, subspecies and economic trait differentiation patterns were analyzed using morphological and molecular (InDel and Intron Length Polymorphism) data in F2 and F3 populations derived from indica-japonica hybridization. Populations were grown in Liaoning and Guangdong provinces, China, with F3 populations generated from F2 populations using bulk harvesting (BM) and single-seed descent methods (SSD). Segregation distortion was detected in F3-BM populations, but not in F3- SSD or in F2 populations. Superior performance was observed with respect to economic traits in Liaoning compared with that in Guangdong and 1 000-grain weight (KW), seed setting rate (SSR) and grain yield per plant (GYP) were significantly correlated with indica and japonica subspecies types. Analysis of molecular and morphological data demonstrated that the environment is the main factor giving rise to population differentiation in indica-japonica hybridization. In addition, we also found that KW, SSR and GYP are related to subspecies characteristics and kinship, which is possibly a significant factor resulting in economic trait differentiation and determining environmental adaptability. Our study has provided new insights into the process of population differentiation in these subspecies to inform indica-japonica hybridization breeding.
    QTLs for Waterlogging Tolerance at Germination and Seedling Stages in Population of Recombinant Inbred Lines Derived from a Cross Between Synthetic and Cultivated Wheat Genotypes
    YU Ma, MAO Shuang-lin, CHEN Guo-yue, LIU Ya-xi, LI Wei, WEI Yu-ming, LIU Chun-ji , ZHENG You-liang
    2014, 13(1): 31-39.  DOI: 10.1016/S2095-3119(13)60354-8
    Abstract ( )   PDF in ScienceDirect  
    Waterlogging is a widespread limiting factor for wheat production throughout the world. To identify quantitative trait loci (QTLs) associated with waterlogging tolerance at early stages of growth, survival rate (SR), germination rate index (GRI), leaf chlorophyll content index (CCI), root length index (RLI), plant height index (PHI), root dry weight index (RDWI), shoot dry weight index (SDWI), and total dry weight index (DWI) were assessed using the International Triticeae Mapping Initiative (ITMI) population W7984/Opata85. Significant and positive correlations were detected for all traits in this population except RLI. A total of 32 QTLs were associated with waterlogging tolerance on all chromosomes except 3A, 3D, 4B, 5A, 5D, 6A, and 6D. Some of the QTLs explained large proportions of the phenotypic variance. One of these is the QTL for GRI on 7A, which explained 23.92% of the phenotypic variation. Of them, 22 alleles from the synthetic hexaploid wheat W7984 contributed positively. These results suggested that synthetic hexaploid wheat W7984 is an important genetic resource for waterlogging tolerance in wheat. These alleles conferring waterlogging tolerance at early stages of growth in wheat could be utilized in wheat breeding for improving waterlogging tolerance.
    Genetic and Association Mapping Study of English Grain Aphid Resistance and Tolerance in Bread Wheat Germplasm
    LI Feng-qi, PENG Jun-hua
    2014, 13(1): 40-53.  DOI: 10.1016/S2095-3119(13)60356-1
    Abstract ( )   PDF in ScienceDirect  
    English grain aphid (EGA) is a destructive insect pest of wheat. To identify the loci associated with EGA resistance and tolerance, 70 bread wheat accessions mainly from central Asia were evaluated for EGA resistance and tolerance traits at two locations, and genotyped with 51 SSR markers. Totally, three accessions showed high or moderate levels resistance and 17 genotypes displayed highly or moderately tolerate to EGA. Genetic diversity of these lines was investigated also. After 97 SSR loci which evenly covered all wheat chromosomes were scanned for association, four SSR loci were significantly associated with EGA resistance and four with EGA tolerance. After association analysis was conducted with dynamic aphid densities, we found four loci Xgwm192b, Xgwm391, Xbarc98, and Xgwm613b were detected continuously at different growing stages of wheat. In addition, the loci of EGA resistance/tolerance and Russian wheat aphid resistance were compared. The results generated in this study would be helpful for utilization of the EGA resistance/tolerance germplasm, and for development of mapping populations in EGA resistance breeding programs.
    Long Chain Acyl-Coenzyme A Synthetase 4 (BnLACS4) Gene from Brassica napus Enhances the Yeast Lipid Contents
    TAN Xiao-li, ZHENG Xiang-feng, ZHANG Zhi-yan, WANG Zheng, XIA Heng-chuan, LU Changming, GU Shou-lai
    2014, 13(1): 54-62.  DOI: 10.1016/S2095-3119(13)60583-3
    Abstract ( )   PDF in ScienceDirect  
    Long-chain acyl-Coenzyme A (CoA) synthetases (LACSs) catalyze the formation of long-chain acyl-CoA, and play important roles in fatty acid metabolism including phospholipids, triacylglycerol (TAG) biosynthesis and fatty acid β-oxidation. Here, we report the characterization of a LACS gene from Brassica napus. It is highly homologous to Arabidopsis LACS4 and thus designated as BnLACS4. The cloned gene BnLACS4 could complement a LACS-deficient yeast strain YB525. It is mainly expressed in flowers and developing seeds where lipid biosynthesis is at high rate in Brassica napus. When transiently expressed in tobacco leaves, BnLACS4 is localized in endoplasmic reticulum (ER), the common site for eukaryotic pathway of lipid biosynthesis. Expression of BnLACS4 in the yeast strain pep4 increased its lipid content. Taken together, our results suggest that BnLACS4 may be involved in lipid biosynthesis in B. napus.
    Effects of Nitrogen Application Rate and Ratio on Lodging Resistance of Super Rice with Different Genotypes
    ZHANG Wu-jun, LI Gang-hua, YANG Yi-ming, LI Quan, ZHANG Jun, LIU Jin-you, WANG Shao-hua, TANG She , DING Yan-feng
    2014, 13(1): 63-72.  DOI: 10.1016/S2095-3119(13)60388-3
    Abstract ( )   PDF in ScienceDirect  
    The objective of this study was to determine the morphology mechanism of nitrogen (N) fertilizer rates and ratio on lodging resistance through analying its effects among lodging index (LI), lodging-related morphological traits and physical strength in basal internodes by comparing japonica and indica super rice cultivars. Field experiments, with three nitrogen levels (0, 150 and 300 kg ha-1) and two ratios of basal to topdressing (8:2 and 5:5) with two super rice cultivars (Yliangyou 2 and Wuyunjing 23), were conducted in the Baolin Farm, Danyang Country, Jiangsu Province, China, in 2011 and 2012. Effects of N fertilizer rates and ratios on morphology of whole plant, morphology traits in basal internodes and culm’s physical strength parameters were investigated at 20 d after full heading stage. LI of Yliangyou 2 was significant greater than that of Wuyunjing 23 due to larger bending moment by whole plant (WP) with higher plant height and gravity center height. With higher volume of N fertilizer, LI of two super rice cultivars was increased conspicuously. However, no significant effect was detected with increase of panicle fertilizer ratio. The size of breaking strength (M) in basal internodes was the key factor determining LI among N fertilizer treatments. Correlation analysis revealed that M value was positively related bending stress (BS) of Wuyunjing 23 and section modulus (Z) of Yliangyou 2, respectively. The higher N fertilizer levels induced reduction of BS of Wuyunjing 23 due to weak culm and leaf sheath plumpness status and reduced Z of Yliangyou 2 owning to small diameter and culm wall thickness, consequently, influencing their M indirectly. These results suggested that breaking strength was the key factor influencing LI with increase of N fertilizer levels. However, the lodging-related morphology mechanism was different with genotypes. Culm wall thickness and diameter in basal internodes of indica super rice and culm and leaf sheath plumpness status of japonica super rice influenced breaking strength, as well as lodging index, respectively.
    Nitrogen Deficiency Limited the Improvement of Photosynthesis in Maize by Elevated CO2 Under Drought
    ZONG Yu-zheng, SHANGGUAN Zhou-ping
    2014, 13(1): 73-81.  DOI: 10.1016/S2095-3119(13)60349-4
    Abstract ( )   PDF in ScienceDirect  
    Global environmental change affects plant physiological and ecosystem processes. The interaction of elevated CO2, drought and nitrogen (N) deficiency result in complex responses of C4 species photosynthetic process that challenge our current understanding. An experiment of maize (Zea mays L.) involving CO2 concentrations (380 or 750 μmol mol-1, climate chamber), osmotic stresses (10% PEG-6000, -0.32 MPa) and nitrogen constraints (N deficiency treated since the 144th drought hour) was carried out to investigate its photosynthesis capacity and leaf nitrogen use efficiency. Elevated CO2 could alleviate drought-induced photosynthetic limitation through increasing capacity of PEPC carboxylation (Vpmax) and decreasing stomatal limitations (SL). The N deficiency exacerbated drought-induced photosynthesis limitations in ambient CO2. Elevated CO2 partially alleviated the limitation induced by drought and N deficiency through improving the capacity of Rubisco carboxylation (Vmax) and decreasing SL. Plants with N deficiency transported more N to their leaves at elevated CO2, leading to a high photosynthetic nitrogen-use efficiency but low whole-plant nitrogen-use efficiency. The stress mitigation by elevated CO2 under N deficiency conditions was not enough to improving plant N use efficiency and biomass accumulation. The study demonstrated that elevated CO2 could alleviate drought-induced photosynthesis limitation, but the alleviation varied with N supplies.
    Relationship Between Leaf C/N Ratio and Insecticidal Protein Expression in Bt Cotton as Affected by High Temperature and N Rate
    ZHANG Xiang, Lü Chun-hua, CHEN Yuan, WANG Gui-xia, CHEN Yuan , CHEN De-hua
    2014, 13(1): 82-88.  DOI: 10.1016/S2095-3119(13)60348-2
    Abstract ( )   PDF in ScienceDirect  
    Expression of insecticidal protein for transgenic Bacillus thuringiensis (Bt) cotton is unstable and related to nitrogen metabolism. The objective of this study was to investigate the relationship between leaf carbon nitrogen ratio (C/N) and insecticidal efficacy of two Bt cotton cultivars. C/N ratio and Bt protein content were both measured at peak square period and peak boll period respectively under 5-7 d high temperature and different nitrogen fertilizer rates on the Yangzhou University Farm and the Ludong Cotton Farm, China. All plants were grown in field. The results showed that the C/N ratio enhanced slightly and the Bt protein content remained stable at peak square period, but significant increases for the C/N ratio and decreases markedly for the leaf Bt protein concentration were detected at the peak boll period. The similar patterns at the two growth periods were found for the leaf C/N ratio and Bt protein content by different N fertilizer treatments. When nitrogen rate was from 0 to 600 kg ha-1, the C/N ratio was reduced by 0.017 and 0.006 for Sikang 1 and Sikang 3 at peak square period, compared to the 1.350 to 1.143 reduction for Sikang 1 and Sikang 3 at peak boll period, respectively. Correspondingly, the leaf Bt protein contents were bolstered by 2.6-11.8 and 26.9-36.9% at the two different growth periods, respectively. The results suggested that enhanced C/N ratio by high temperature and nitrogen application may result in the reduction of insectiocidal efficacy in Bt cotton, especially in peak boll period.
    Animal Science · Veterinary Science
    Low Root Zone Temperature Exacerbates the Ion Imbalance and Photosynthesis Inhibition and Induces Antioxidant Responses in Tomato Plants Under Salinity
    HE Yong, YANG Jing, ZHU Biao , ZHU Zhu-jun
    2014, 13(1): 89-99.  DOI: 10.1016/S2095-3119(13)60586-9
    Abstract ( )   PDF in ScienceDirect  
    The combined effects of salinity with low root zone temperature (RZT) on plant growth and photosynthesis were studied in tomato (Solanum lycopersicum) plants. The plants were exposed to two different root zone temperatures (28/20°C, 12/8°C, day/night temperature) in combination with two NaCl levels (0 and 100 mmol L-1). After 2 wk of treatment, K+ and Na+ concentration, leaf photosynthetic gas exchange, chlorophyll fluorescence and leaf antioxidant enzyme activities were measured. Salinity significantly decreased plant biomass, net photosynthesis rate, actual quantum yield of photosynthesis and concentration of K+, but remarkably increased the concentration of Na+. These effects were more pronounced when the salinity treatments were combined with the treatment of low RZT conditions. Either salinity or low RZT individually did not affect maximal efficiency of PSII photochemistry (Fv/Fm), while a combination of these two stresses decreased Fv/Fm considerably, indicating that the photo-damage occurred under such conditions. Non-photochemical quenching was increased by salt stress in accompany with the enhancement of the de-epoxidation state of the xanthophyll cycle, in contrast, this was not the case with low RZT applied individually. Salinity stress individually increased the activities of SOD, APX, GPOD and GR, and decreased the activities of DHAR. Due to the interactive effects of salinity with low RZT, these five enzyme activities increased sharply in the combined stressed plants. These results indicate that low RZT exacerbates the ion imbalance, PSII damage and photosynthesis inhibition in tomato plants under salinity. In response to the oxidative stress under salinity in combination with low RZT, the activities of antioxidant enzymes SOD, APX, GPOD, DHAR and GR were clearly enhanced in tomato plants.
    Plant Protection
    Development of SSR Markers for a Phytopathogenic Fungus, Blumeria graminis f.sp. tritici, Using a FIASCO Protocol
    WANGMeng123 , XUEFei4 , YANGPeng15 , DUANXia-yu1 , ZHOUYi-lin1 , SHENChong-yao2 , ZHANGGuo-zhen2 , WANGBao-tong5
    2014, 13(1): 100-104.  DOI: 10.1016/S2095-3119(13)60510-9
    Abstract ( )   PDF in ScienceDirect  
    Simple sequence repeats (SSR) have been widely used as molecular markers due to their abundance and high polymorphism. However, up to now, the SSR markers had not been developed in the obligate biotrophic phytopathogenic fungus, Blumeria graminis f.sp. tritici. From (AC)10 and (AG)10 enriched genomic libraries for Bgt, 25 primer pairs were designed using the FIASCO (fast isolation by AFLP of sequences containing repeats) protocol. Five primer pairs exhibited polymorphism with allelic diversity from two to seven alleles and produced 29 alleles in a survey of 90 isolates collected from six provinces (cities) in China, while the others displayed monomorphic. Levels of observed heterozygosity ranged from 0.000-0.044 (mean 0.025) and expected heterozygosity ranged from 0.297-0.816 (mean 0.538). These molecular markers provide a novel source to genetic diversity assays and to genetic and physical mapping of Bgt. SSR markers of Bgt need to be further explored.
    The Extraction, Isolation and Identification of Exudates from the Roots of Flaveria bidentis
    YANG Xing, ZHANG Li-hui, SHI Cui-ping, SHANG Yan, ZHANG Jin-lin, HAN Jian-min , DONG
    2014, 13(1): 105-114.  DOI: 10.1016/S2095-3119(13)60495-5
    Abstract ( )   PDF in ScienceDirect  
    Large amounts of Flaveria bidentis’s root culturing solution were obtained by using DFT (deep flow technique) equipment and these solution which was vacuum concentrated (10, 20 mg mL-1) can have a certain inhibition on Triticum aestivum, Cucumis sativus, Raphanus sativus, Amaranthus retroflexus, Setaria viridis, Chenopodium album, Echinochloa crusgalli and Chloris virgata. This outcome suggested some active compounds in the root exudates of Flaveria bidentis can inhibit the germination, seedling elongation and root length. The dichloromethane extract of root exudates was identificated by GC-MS, and 29 kinds of compounds, including esters, hydrocarbons, ketones, thiazole, amines, etc. were obtained and the phthalate n-octyl ester, phthalate 2-ethylhexyl ester were proved to be allelochemicals. The culturing solution of root exudates was separated through the resin column and silica gel column and a component inhibiting seedling height, root length and fresh weight of wheat was got. There were 6 kinds of organic compounds in this component including dioctyl phthalate, 1,2-phthalate, mono(2-ethylhexyl) ester by GC-MS.
    Efficiency of Different Methods for dsRNA Delivery in Cotton Bollworm (Helicoverpa armigera)
    YANG Jing , HAN Zhao-jun
    2014, 13(1): 115-123.  DOI: 10.1016/S2095-3119(13)60511-0
    Abstract ( )   PDF in ScienceDirect  
    RNAi trigged by dsRNA not only facilitates the development of molecular biology, but also initiates a new way for pest control by silence of fatal genes. However, one of the key limitations in pest control is lack of the convenient and efficient method for dsRNA delivery. In this study, different dsRNA delivery methods at their own optimum conditions were evaluated comparatively for their efficiency with Helicoverpa armigera as test animal. It was found that the popular one- time injection of larvae with dsRNA could reduce the pupation rate by 43.0% and enhance larva mortality by 11.7%. One- time ingestion of dsRNA did not result in any significant effect on phenotype. Continuous ingestion of in vitro synthesized dsRNA by refreshing the bait diet every day caused 40.4% decrease in successful pupation and 10.0% increase in larval mortality, which was similar as one-time injection. The most efficient method was found to be the continuous ingestion of the bacteria containing dsRNA expressed, which reduced the rate of pupation by 68.7% and enhanced the larval mortality by 34.1%. Further analysis found that dsRNA was degraded faster in midgut juice than in hemolymph. However, the cell of bacteria could protect dsRNA and delay the degradation in the midgut juice of H. armigera. These results throw light on the application of dsRNA in pest management with proper ways.
    Effects of Droplet Distribution on Insecticide Toxicity to Asian Corn Borers (Ostrinia furnaealis) and Spiders (Xysticus ephippiatus)
    YANG Dai-bin, ZHANG Lin-na, YAN Xiao-jing, WANG Zhen-ying , YUAN Hui-zhu
    2014, 13(1): 124-133.  DOI: 10.1016/S2095-3119(13)60507-9
    Abstract ( )   PDF in ScienceDirect  
    Distribution of horizontal boom produced droplets downwards into maize canopies at flowering period and its effects on the efficacies of emamectin benzoate, lambda-cyhalothrin and chlorantraniliprole against the second generation of Asian corn borer (ACB) larvae and their toxicity to spiders were studied. When insecticides were sprayed downwards into the maize canopies, randomly filtering out droplets by upper leaves led to great variations of droplet coverage and density within the canopies. Consequently, the efficacies of lambda-cyhalothrin and emamectin benzoate against ACB larvae were decreased because of randomly filtering out droplets by upper leaves. But field investigation showed that lambda-cyhalothrin was extremely toxic to hunting spiders, Xysticus ephippiatus, and not suitable to IPM programs in regulation of the second generation of ACB. Therefore,randomly filtering out droplets by upper leaves decreased lambda-cyhalothrin’s efficacy against ACB larvae, but did little to decrease its toxicity to X. ephippiatus. Amamectin benzoate can reduce the populations of X. ephippiatus by 58.1-61.4%, but the populations can recover at the end of the experiment. Chlorantraniliprole was relatively safe to X. ephippiatus. It only reduced the populations of X. ephippiatus by 22.3-33.0%, and the populations can totally recover 9 d after application.
    Animal Science · Veterinary Science
    Effect of Different Initial pH on the Storage Characteristics and Shelf Life of Liquid Diet for Suckling and Weanling Piglets
    HE Yu-yong, MA Pen, LIU Xiao-lan, WANG Ren-hua , LU Wei
    2014, 13(1): 134-139.  DOI: 10.1016/S2095-3119(13)60662-0
    Abstract ( )   PDF in ScienceDirect  
    An experiment was conducted to investigate the effect of different initial pH on the storage characteristics and shelf life of liquid diet. 45 polypropylene bags were allotted to treatments 1, 2 and 3 on average, 100 g diet and 200 g water were placed into each polypropylene bag, food-grade DL-lactic acid was added to each bag at a rate of 0.0 mL in treatment 1, 1.2 mL in treatment 2 and 4.7 mL in treatment 3, air was artificially expelled from each bag prior to heat-sealing. All bags were placed into a cage, cooked with steam at 90°C for 30 min under normal pressure, then taken out and stored from day 0 to 60 at room temperature. Results indicated that liquid diet in treatment 3 achieved the highest total sensory scores, the pH value had a tendency to decrease and the bacteria count had a tendency to increase in the liquid diet with the advancing of storage time with the advancing of storage time, lowering the initial pH of liquid diet decreased the bacteria count, the AFB1 and ZEN concentrations and increased the starch gelatinization degree from day 30 to 60, liquid diet in treatment 3 had a lower (P<0.01) bacteria count and a higher (P<0.05) starch gelatinization degree at day 30 and 45 than liquid diet in treatment 1. In conclusion, lowering the initial pH of liquid diet with lactic acid to pH 4 could effectively improve the storage characteristics and shelf life of liquid diet.
    The Estimation of Soil Trace Elements Distribution and Soil-Plant- Animal Continuum in Relation to Trace Elements Status of Sheep in Huangcheng Area of Qilian Mountain Grassland, China
    WANG Hui, LIU Yong-ming, QI Zhi-ming, WANG Sheng-yi, LIU Shi-xiang, LI Xia, WANG Hai-jun, WANG Xiao-li, XIA Xin-chao , ZHU Xin-qiang
    2014, 13(1): 140-147.  DOI: 10.1016/S2095-3119(13)60504-3
    Abstract ( )   PDF in ScienceDirect  
    The purpose of the present study was to survey contents of trace elements of Cu, Mn, Fe, and Zn in the surface layer (0-20 cm) in the soil, pasture and serum of sheep in Huangcheng area of Qilian mountain grassland, China. Also the soil-plant- animal continuum was analyzed. Soil (n=300), pasture (n=60), and blood serum samples from sheep (n=480) were collected from Huangcheng area of Qilian mountain grassland, China. The contents of trace element in the samples were analyzed by atomic absorption spectrophotometer after digestion. The soil trace elements density distribution shows a ladder-like pattern distribution. Equations developed in the present study for prediction of Fe (R2=0.943) and Zn (R2=0.882) had significant R2 values.
    Determination of Residual Feed Intake and Its Associations with Single Nucleotide Polymorphism in Chickens
    XU Zhen-qiang, CHEN Jie, ZHANG Yan, JI Cong-liang, ZHANG De-xiang , ZHANG Xi-quan
    2014, 13(1): 148-157.  DOI: 10.1016/S2095-3119(13)60383-4
    Abstract ( )   PDF in ScienceDirect  
    Marker assisted selection (MAS) for residual feed intake (RFI) is considered to be one of the powerful means to improve feed conversion efficiency, and therefore reduce production costs. To test the inner relationship among body compositions, growth traits and RFI, four models were proposed to assess the extensively explanatory variables accounting for partial variables in feed intake besides metabolic body weight and growth rate. As a result, the original model (Koch’s model) had the lowest R2 (80.78%) and the highest Bayesian information criterion (1 323.3) value among the four models. Moreover, the effects on RFI caused by single nucleotide polymorphisms (SNPs) were assessed in this study. Twelve SNPs from 7 candidate genes were genotyped in 2 Chinese native strains. rs14743490 of RPLP2 gene showed suggestively significant association with initial body weight in both strains (P<0.10). rs15047274 of TAF15 was significantly associated with growth weight, final weight, and feed intake (P<0.05) in N301 strain, in contrast, it was only suggestively significant associated with feed intake (P<0.10) in N414 strain. rs15869967 was significantly associated with RFI in N414 strain but not in N301 strain. This study has identified potential genetic markers suitable for MAS in improving the above mentioned traits, but these associations need to be rectified in other larger populations in future.
    Metabolism of Mequindox in Isolated Rat Liver Cells
    LIGuang-hui12 , SHANQi1 , WANGJing1 , LIYa-fei1 , GAOYan1 , ZENGZhen-ling1
    2014, 13(1): 158-166.  DOI: 10.1016/S2095-3119(13)60335-4
    Abstract ( )   PDF in ScienceDirect  
    Mequindox (MEQ), 3-methyl-2-quinoxalinacetyl-1,4-dioxide, is widely used in Chinese veterinary medicine as an antimicrobial agent and feed additive. Its toxicity has been reported to be closely related to its metabolism. To understand the pathways underlying MEQ’s metabolism more clearly, we studied its metabolism in isolated rat liver cells by using liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole orbitrap (LC-LTQ-Orbitrap) mass spectrometry. The structures of MEQ metabolites and their product ions were readily and reliably characterized on the basis of accurate MS2 spectra and known structure of MEQ. Eleven metabolites were detected in isolated rat liver cells, two of which were detected for the first time in vitro. The major metabolic pathways reported previously for in vitro metabolism of MEQ in rat microsomes were confirmed in this study, including N → O group reduction, carbonyl reduction, and methyl monohydroxylation. In addition, we found that acetyl hydroxylation was an important pathway of MEQ metabolism. The results also demonstrate that cellular systems more closely simulate in vivo conditions than do other in vitro systems such as microsomes. Taken together, these data contribute to our understanding of the in vivo metabolism of MEQ.
    Soil & Fertilization · Irrigation · Agro-Ecology & Environment
    A 15N-Labeling Study of the Capture of Deep Soil Nitrate from Different Plant Systems
    YANG Zhi-xin, WANG Jue, DI Hong-jie, ZHANG Li-juan , JU Xiao-tang
    2014, 13(1): 167-176.  DOI: 10.1016/S2095-3119(13)60402-5
    Abstract ( )   PDF in ScienceDirect  
    The objective of this study was to determine the efficiency of different plant systems in capturing deep soil nitrate (NO3 -) to reduce NO3 - leaching in a field plot experiment using 15N labelling. The study was conducted on a calcareous alluvial soil on the North China Plains and the plant systems evaluated included alfalfa (Medicago sativa), American black poplar (Populus nigra) and cocksfoot (Dactylis). 15N-labelled N fertilizer was injected to 90 cm depth to determine the recovery of 15N by the plants. With conventional water and nutrient management, the total recovery of 15N-labeled NO3 --N was 23.4% by alfalfa after two consecutive growth years. The recovery was significantly higher than those by American black poplar (12.3%) and cocksfoot (11.4%). The highest proportion of soil residual 15N from the labeled fertilizer N (%Ndff) was detected around 90 cm soil depth at the time of the 1st year harvest and at 110-130 cm soil depth at time of the 2nd year harvest. Soil %Ndff in 0-80 cm depth was significantly higher in the alfalfa treatment than those in all the other treatments. The soil %Ndff below 100 cm depth was much lower in the alfalfa than those in all the other treatments. These results indicated that 15N leaching losses in the alfalfa treatment were significantly lower than by those in the black poplar and cocksfoot treatments, due to the higher root density located in nitrate labeling zone of soil profile. In conclusion, alfalfa may be used as a plant to capture deep soil NO3 - left from previous crops to reduce NO3 - leaching in high intensity crop cultivation systems of North China Plain.
    Soil Quality Assessment of Acid Sulfate Paddy Soils with Different Productivities in Guangdong Province, China
    LIU Zhan-jun, ZHOU Wei, SHEN Jian-bo, LI Shu-tian, LIANG Guo-qing, WANG Xiu-bin, SUN Jing-wen , AI Chao
    2014, 13(1): 177-186.  DOI: 10.1016/S2095-3119(13)60594-8
    Abstract ( )   PDF in ScienceDirect  
    Land conversion is considered an effective measure to ensure national food security in China, but little information is available on the quality of low productivity soils, in particular those in acid sulfate soil regions. In our study, acid sulfate paddy soils were divided into soils with high, medium and low levels based on local rice productivity, and 60 soil samples were collected for analysis. Twenty soil variables including physical, chemical and biochemical properties were determined. Those variables that were significantly different between the high, medium and low productivity soils were selected for principal component analysis, and microbial biomass carbon (MBC), total nitrogen (TN), available silicon (ASi), pH and available zinc (AZn) were retained in the minimum data set (MDS). After scoring the MDS variables, they were integrated to calculate a soil quality index (SQI), and the high, medium and low productivity paddy soils received mean SQI scores of 0.95, 0.83 and 0.60, respectively. Low productivity paddy soils showed worse soil quality, and a large discrepancy was observed between the low and high productivity paddy soils. Lower MBC, TN, ASi, pH and available K (AK) were considered as the primary limiting factors. Additionally, all the soil samples collected were rich in available P and AZn, but deficient in AK and ASi. The results suggest that soil AK and ASi deficiencies were the main limiting factors for all the studied acid sulfate paddy soil regions. The application of K and Si on a national basis and other sustainable management approaches are suggested to improve rice productivity, especially for low productivity paddy soils. Our results indicated that there is a large potential for increasing productivity and producing more cereals in acid sulfate paddy soil regions.
    Spatiotemporal Changes in Soil Nutrients: A Case Study in Taihu Region of China
    LIU Lei-lei, ZHU Yan, LIU Xiao-jun, CAO Wei-xing, XU Mao, WANG Xu-kui , WANG En-li
    2014, 13(1): 187-194.  DOI: 10.1016/S2095-3119(13)60528-6
    Abstract ( )   PDF in ScienceDirect  
    The accurate assessment of the spatiotemporal changes in soil nutrients influenced by agricultural production provides the basis for development of management strategies to maintain soil fertility and balance soil nutrients. In this paper, we combined spatial measurements from 2 157 soil samples and geostatistical analysis to assess the spatiotemporal changes in soil organic carbon (SOC), total nitrogen (TN), available phosphorus (AP) and available potassium content (AK) from the first soil survey (in the 1980s) to the second soil survey (in the 2000s) in the Taihu region of Jiangsu Province in China. The results showed that average soil nutrients in three soil types all exhibited the increased levels in the 2000s (except for AK in the yellow brown soil). The standard deviation of soil nutrient contents increased (except for TN in the paddy soil). Agricultural production in the 20 years led to increases in SOC, TN, AP and AK by 74, 82, 89 and 65%, respectively, of the Taihu areas analyzed. From the 1980s to 2000s all the nugget/sill ratios of soil nutrients indices were between 25 and 75% (except for AK in the yellow brown soil in the 2000s), indicating moderate spatial dependence. The ratio of AP in the yellow brown soil in the 2000s was 88.74%, showing weak spatial dependence. The spatial correlation range values for SOC, TN, AP and AK in the 2000s all decreased. The main areas showing declines in SOC, TN and AP were in the northwest. For AK, the main region with declining levels was in the east and middle of western areas. Apparently, the increase in soil nutrients in the Taihu region can be mainly attributed to the large increase in fertilizer inputs, change in crop systems and enhanced residues management since the 1980s. Future emphasis should be placed on avoiding excess fertilizer inputs and balancing the effects of the fertilizers in soils.
    Quantitative Evaluation of Sustainable Development and Eco- Environmental Carrying Capacity in Water-Deficient Regions: A Case Study in the Haihe River Basin, China
    WANG Zhong-gen, LUO Yu-zhou, ZHANG Ming-hua , XIA Jun
    2014, 13(1): 195-206.  DOI: 10.1016/S2095-3119(13)60423-2
    Abstract ( )   PDF in ScienceDirect  
    Quantitative assessment of development sustainability could be a challenge to regional management and planning, especially for areas facing great risks of water shortage. Surface-water decline and groundwater over-pumping have caused serious environmental problems and limited economic development in many regions all around the world. In this paper, a framework for quantitatively evaluating development sustainability was established with water-related eco-environmental carrying capacity (EECC) as the core measure. As a case study, the developed approach was applied to data of the Haihe River Basin, China, during 1998 through 2007. The overall sustainable development degree (SDD) is determined to be 0.39, suggesting that this rate of development is not sustainable. Results of scenario analysis revealed that overshoot, or resource over- exploitation, of the Basin’s EECC is about 20% for both population and economy. Based on conditions in the study area in 2007, in order to achieve sustainable development, i.e., SDD>0.70 in this study, the EECC could support a population of 108 million and gross domestic product (GDP) of 2.72 trillion CNY. The newly developed approach in quantifying eco- environmental carrying capacity is anticipated to facilitate sustainable development oriented resource management in water- deficient areas.
    Food Science
    Mathematical Modeling and Effect of Various Hot-Air Drying on Mushroom (Lentinus edodes)
    GUO Xiao-hui, XIA Chun-yan, TAN Yu-rong, CHEN Long , MING Jian
    2014, 13(1): 207-216.  DOI: 10.1016/S2095-3119(13)60265-8
    Abstract ( )   PDF in ScienceDirect  
    An experimental study was performed to determine the characteristics and drying process of mushroom (Lentinus edodes) by 6 different hot-air drying methods namely isothermal drying, uniform raise drying, non-uniform raise drying, uniform intermittent drying, non-uniform intermittent drying and combined drying. The chemical composition (dry matter, ash, crude protein, crude fat, total sugars, dietary fiber, and energy), color parameters (L, a*, b*, c*, and h0) and rehydration capacities were determined. Among all the experiments, non-uniform intermittent drying reached a better comprehensive results due to the higher chemical composition, better color quality associated with high bright (26.381±5.842), high color tone (73.670±2.975), low chroma (13.349±3.456) as well as the highest rehydration (453.76% weigh of dried body). Nine kinds of classical mathematical model were used to obtained moisture data and the Midili-kucuk model can be described by the drying process with the coefficient (R2 ranged from 0.99790 to 0.99967), chi-square (χ2 ranged from 0.00003 to 0.00019) and root mean square error (RMSE ranged from 0.000486 to 0.0012367).
    Co-Treatment of EFF and 1-MCP for Enhancing the Shelf-Life and Aroma Volatile Compounds of Oriental Sweet Melons (Cucumis melo var. makuwa Makino)
    BAI Xiao-hang, TENG Lu-hua, Lü De-qing , QI Hong-yan
    2014, 13(1): 217-227.  DOI: 10.1016/S2095-3119(13)60372-X
    Abstract ( )   PDF in ScienceDirect  
    Compared to other melon types, oriental sweet melon (Cucumis melo var. makuwa Makino) is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of this experiment is to explore the effects of co- treatment of enhanced freshness formulation (EFF) and 1-methylcyclopropene (1-MCP) on physiological changes and the content of aroma volatile compounds introduced by them of two oriental sweet melon cultivars (Yumeiren and Tianbao) during storage. The melons were stored in incubators with temperature of 15°C and a relative humidity of 85% for 24 d during which fruit quality and related physiological index were measured. Compared to the control, both treatments delayed fruit weight loss rate and kept the fruit firmness, water content and soluble solids content. Ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) activities showed fluctuations in treated melons, while lipoxygenase (LOX) activity (P<0.01) and malondialdehyde (MDA) content (P<0.05) decreased compared to control. During the early stage of storage, alcohols and aldehydes were the main volatile compounds, and esters gradually increased during storage. Of all the esters, acetic esters were the main components, followed by oxalic acid esters and other esters. The total content of aroma volatile compounds, esters, alcohols and aldehydes of co-treated melons were all higher than those of 1-MCP treated and control melons. In addition, the aroma volatile peak of co-treated melons occurred later than that of 1-MCP treated and control melons. In summary, co-treatment of EFF and 1-MCP was more beneficial than 1-MCP treatment to delay ripening and senescence, maintain fruit quality, enhance shelf-life and improve levels of aroma volatile compounds.