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    Review
    Tillage, crop residue, and nutrient management effects on soil organic carbon in rice-based cropping systems: A review
    Rajan Ghimire, Sushil Lamichhane, Bharat Sharma Acharya, Prakriti Bista, Upendra Man Sainju
    2017, 16(01): 1-15.  DOI: 10.1016/S2095-3119(16)61337-0
    Abstract ( )   PDF in ScienceDirect  
    Soil organic carbon (SOC) sequestration is one of the major agricultural strategies to mitigate greenhouse gas (GHG) emissions, enhance food security, and improve agricultural sustainability. This paper synthesizes the much-needed state-of-knowledge on the effects of tillage, crop residue, and nutrient management practices on SOC sequestration and identifies potential research gap, opportunities, and challenges in studying SOC dynamics in rice (Oryza sativa L.)-based cropping systems in South Asia, mainly in Bangladesh, Bhutan, India, Nepal, Pakistan, and Sri Lanka. Improved management practices such as reduced- and no-tillage management, nitrogen (N) fertilizer and farmyard manure (FYM) application, and crop residue addition can improve SOC accumulation. Positive effects of no-tillage, crop residue addition, N addition through manure or compost application, and integration of organic and chemical fertilizers on SOC accumulation in rice-based cropping systems have been documented from South Asia. However, limited data and enormous discrepancies in SOC measurements across the region exist as the greatest challenge in increasing SOC sequestration and improving agricultural sustainability. More research on SOC as influenced by alternative tillage, crop residue, and nutrient management systems, and development of SOC monitoring system for existing long-term experiments will advance our understanding of the SOC dynamics in rice-based cropping systems and improve agricultural system sustainability in South Asia.
    Crop Genetics · Breeding · Germplasm Resources
    Validation of qGS10, a quantitative trait locus for grain size on the long arm of chromosome 10 in rice (Oryza sativa L.)
    WANG Zhen, CHEN Jun-yu, ZHU Yu-jun, FAN Ye-yang, ZHUANG Jie-yun
    2017, 16(01): 16-26.  DOI: 10.1016/S2095-3119(16)61410-7
    Abstract ( )   PDF in ScienceDirect  
    Grain size is a major determinant of grain weight and a trait having important impact on grain quality in rice. The objective of this study is to detect QTLs for grain size in rice and identify important QTLs that have not been well characterized before. The QTL mapping was first performed using three recombinant inbred line populations derived from indica rice crosses Teqing/IRBB lines, Zhenshan 97/Milyang 46, Xieqingzao/Milyang 46. Fourteen QTLs for grain length and 10 QTLs for grain width were detected, including seven shared by two populations and 17 found in one population. Three of the seven common QTLs were found to coincide in position with those that have been cloned and the four others remained to be clarified. One of them, qGS10 located in the interval RM6100–RM228 on the long arm of chromosome 10, was validated using F2:3 populations and near isogenic lines derived from residual heterozygotes for the interval RM6100–RM228. The QTL was found to have a considerable effect on grain size and grain weight, and a small effect on grain number. This region was also previously detected for quality traits in rice in a number of studies, providing a good candidate for functional analysis and breeding utilization.
    Expression and functional analyses of the mitogen-activated protein kinase (MPK) cascade genes in response to phytohormones in wheat (Triticum aestivum L.)
    YAO Su-fei, WANG Yan-xia, YANG Tong-ren, HAO Lin, LU Wen-jing, XIAO Kai
    2017, 16(01): 27-35.  DOI: 10.1016/S2095-3119(16)61367-9
    Abstract ( )   PDF in ScienceDirect  
    Mitogen-activated protein kinase (MPK) cascades consist of a set of kinase types (MPKKKs, MPKKs, MPKs) to establish
    conserved signal-transducing modules mediating plant growth, development as well as responses to internal and external
    cues. In this study, the expression patterns of six MPKKK, two MPKK, and 11 MPK genes in wheat in responses to external
    treatments of phytohormones, including naphthylacetic acid (NAA), abscisic acid (ABA), 6-benzyladenine (6-BA), gibberellin
    (GA3), salisylic acid (SA), jasmonic acid (JA), and ethylene (ETH), were investigated. Expression analysis revealed
    that several of the MPK cascade genes are responses to the external phytohormone signaling. Of which, TaMPKKKA;3
    is induced by 6-BA and NAA while TaMPK4 repressed by ETH, GA3, SA, and JA; TaMPKKKA, TaMPKKKA;3 and TaMPK1
    are down-regulated by ETH and GA3 whereas TaMPK9 and TaMPK12 repressed by ETH and JA in addition that TaMPK12
    also repressed by GA3; TaMPK12;1 is down-regulated by ABA, GA3 and SA while TaMPK17 repressed by all exogenous
    phytonormones examined. TaMPK4, a MPK type gene previously characterized to mediate tolerance to phosphate (Pi)
    deprivation, was functionally evaluated for its role in mediation of responses of plants to exogenous GA3, ETH, SA, and JA.
    Results indicated that overexpression and antisense expression of TaMPK4 in tobacco dramatically modify the growth of
    seedlings upon treatments of GA3, SA and JA, in which the overexpressors behaved deteriorated growth feature whereas
    the seedlings with antisense expression of TaMPK4 exhibited improved seedling phenotype. The growth behaviors in
    lines overexpressing or antisensely expressing TaMPK4 are closely associated with the biomass and the corresponding
    hormone-associated parameters. These results demonstrated that TaMPK4 acts as a critical player in mediating the phytohormone
    signaling. Our findings have identified the phytohormone-responsive MPK cascade genes in wheat and provided
    a connection between the phytohormone-mediated responses and the MPK cascade pathways.
    Analysis of drought tolerance and genetic and epigenetic variations in a somatic hybrid between Ipomoea batatas (L.) Lam. and I. triloba L.
    JIA Li-cong, ZHAI Hong, HE Shao-zhen, YANG Yu-feng, LIU Qing-chang
    2017, 16(01): 36-46.  DOI: 10.1016/S2095-3119(16)61359-X
    Abstract ( )   PDF in ScienceDirect  
    The somatic hybrid KT1 was previously obtained from protoplast fusion between sweetpotato (Ipomoea batatas (L.) Lam.) cv. Kokei No. 14 and its wild relative I. triloba L. However, its genetic and epigenetic variations have not been investigated. This study showed that KT1 exhibited significantly higher drought tolerance compared to the cultivated parent Kokei No. 14. The content of proline and activities of superoxide dismutase (SOD) and photosynthesis were significantly increased, while malonaldehyde (MDA) content was significantly decreased compared to Kokei No. 14 under drought stress. KT1 also showed higher expression level of well-known drought stress-responsive genes compared to Kokei No. 14 under drought stress. Amplified fragment length polymorphism (AFLP) and methylation-sensitive amplified polymorphism (MSAP) analyses indicated that KT1 had AFLP and MSAP band patterns consisting of both parent specific bands and changed bands. Further analysis demonstrated that in KT1 the proportions of Kokei No. 14 specific genome components and methylation sites were much greater than those of I. triloba. KT1 had the same chloroplast and mitochondrial genomes as Kokei No. 14. These results will aid in developing the useful genes of I. triloba and understanding the evolution and phylogeny of the cultivated sweetpotato.
    cDNA-Amplified fragment length polymorphism analysis reveals differential gene expression induced by exogenous MeJA and GA3 in oilseed rape (Brassica apus L.) flowers
    Haksong Pak, LI Yu-ling, Hyenchol Kim, JIANG Li-xi
    2017, 16(01): 47-56.  DOI: 10.1016/S2095-3119(16)61407-7
    Abstract ( )   PDF in ScienceDirect  
    The transition of a plant from vegetative to reproductive stage is controlled by a large group of genes, which respond to environmental and endogenous stimuli. Application of methyl jasmonate (MeJA) and gibberellins (GA3) to oilseed plants (Brassica napus L.) interrupts the delicate endogenous balance and results in various floral organ abnormalities. Exogenous MeJA or GA3 influences the transcriptome at the initial flowering stage in Arabidopsis, but the corresponding changes of transcriptome in floral tissues of oilseed rape remain unknown. In this study, cDNA-amplified fragment length polymorphism (cDNA-AFLP) was analyzed to identify genes whose expression was modulated by application of MeJA and GA3 to flower buds. A total of 2 787 cDNA fragments were counted using 64 primer pair combinations, and bands larger than 50 bp were compared among four treatments, namely, water control, MeJA (50 µmol L-1), MeJA (100 µmol L-1), and GA3 (50 µmol L-1). Overall, 168 transcript-derived fragments (TDFs) were differentially expressed among the treatments. The expression pattern of some TDFs was confirmed by semi-quantitative RT-PCR analysis, and a group of 106 differentially displayed TDFs was cloned and sequenced. Homologs of Arabidopsis genes were identified and classified into 12 functional categories. A total of 34, 39, and 24 TDFs were responsive to GA3, MeJA, and both GA3 and MeJA, respectively. This finding indicated that cross-talk between these two hormones may be involved in regulating flower development. This study provides potential target genes for manipulation in terms of flowering time and floral organ initiation, important agronomic traits of oilseed rape.
    Bacterial artificial chromosome library construction of root-knot nematode resistant pepper genotype HDA149 and identification of clones linked to Me3 resistant locus
    GUO Xiao, YANG Xiao-hui, YANG Yu, MAO Zhen-chuan, LIU Feng, MA Wei-qing, XIE Bing-yan, LI Guang-cun
    2017, 16(01): 57-64.  DOI: 10.1016/S2095-3119(16)61446-6
    Abstract ( )  
    Pepper (Capsicum annuum. L.) is a widely cultivated vegetable crop worldwide and has the second largest planting area and the first largest vegetable output and value in China.  Pepper root-knot nematode (Meloidogyne spp.) is one of the most serious pests of pepper, which caused huge losses every year.  Previous studies showed that the Me3 gene is resistant to a wide range of Meloidogyne species, including M. arenaria, M. javanica, and M. incognita.  HDA149, a double haploid pepper genotype, harboring the root-knot nematode resistance gene Me3, was used to construct bacterial artificial chromosome library (BAC) via the vector of CopyControlTM pCC1 in this study.  The library consists of 210 200 BAC clones and is equivalent to 5.3 pepper genomes.  The average insert size is 95 kb, and most of them are 90–120 kb; but the empty clones are less than 3%.  In order to screen the BAC library easily, 550 super pools with 384 BAC clones of each pool were further developed in this study.  Specific primers from Me3 gene locus were used for BAC library screening, and more than 20 positive BAC clones were obtained.  Then the selected positive BAC clones were analyzed by restriction enzyme digestion, BAC-end sequencing, marker development, and new positive BAC clones exploration, respectively.  Finally, the contig with total length of about 300 kb linked to the Me3 locus was constructed based on chromosome walking strategy, which made a solid foundation for the cloning of the important root-knot nematode resistance gene Me3.
    SlMYB1 and SlMYB2, two new MYB genes from tomato, transcriptionally regulate cellulose biosynthesis in tobacco
    SHI Yan-na, LIU Xiao-fen, LI Xue, DONG Wen-cheng, Donald Grierson, YIN Xue-ren, CHEN Kun-song
    2017, 16(01): 65-75.  DOI: 10.1016/S2095-3119(16)61389-8
    Abstract ( )   PDF in ScienceDirect  
    Cellulose, a major constituent of plant biomass, is synthesized by a cellulose synthase complex.  It has been demonstrated that MYB genes transcriptionally regulate cellulose synthase in Arabidopsis.  However, little is known about this process in tomato.  Here, two MYB (SlMYB1/2) and three cellulose synthase (CESA) (SlCESA4/5/6) genes were isolated.  SlMYB1/2 and SlCESA4/5/6 accumulation was found to correspond to cellulose accumulation in different tissues of tomato.  Dual luciferase assays indicated that these two MYBs were transcriptional activators that interact with promoters of SlCESA4/5/6.  Moreover, SlMYB2 could also activate promoters of SlMYB1/2, suggesting the possible underlying auto-activation mechanisms for MYB transcription factors.  Transient over-expression of SlMYB1/2 in Nicotiana tabacum up-regulated tobacco endogenous NtCESA genes and increased cellulose accumulation.  The function of SlMYB1/2 was further investigated using stable transformation and the results indicated that N. tabacum lines heterologous expressing SlMYB1/2 displayed a pleiotropic phenotype, long and narrow leaves, with NtCESA induced and significant increase of cellulose.  In conclusion, our data suggest that tomato SlMYB1/2 have transcriptional regulatory roles in cellulose biosynthesis and SlMYB2 was more effective than SlMYB1, which may due to the transcriptional activation by SlMYB2 on SlMYB1 and itself.
    Physiology·Biochemistry·Cultivation·Tillage
    Impacts of the north migration of China’s rice production on its ecosystem service value during the last three decades (1980–2014)
    FANG Fu-ping, FENG Jin-fei, LI Feng-bo, PENG Shao-bing
    2017, 16(01): 76-84.  DOI: 10.1016/S2095-3119(16)61360-6
    Abstract ( )   PDF in ScienceDirect  
    The ecosystem services value (ESV) of rice system has received increasing attention in agricultural policy decision. Over the last three decades, China’s rice production presented an obviously trend that moving towards north locations. However, the impacts of this migration on the ESV of rice production have not been well documented. In this paper, we analyzed the change of the ESV of rice production in China under “north migration” and “no migration” scenarios during 1980–2014 based on long-term historical data. The results showed that both the positive and negative ESVs of rice production were lower under “north migration” than under “no migration” scenarios. The total ESV during 1980–2014 was reduced by 15.8%. “North migration” significantly reduced the area-scaled ESV since the early 1990s; while its impact on yield-scaled ESV was not significant. The effects of “north migration” on ESV showed great spatial variation. The greatest reduction in total and area-scaled ESV was observed in south locations. While the yield-scaled ESVs of most south locations were enhanced under “north migration” scenario. These results indicated that “north migration” has generated adverse effects on the ESV of rice production. An adjustment in the spatial distribution is essential to protecting the non-production benefits of rice ecosystem.
    Effect of leaf removal on photosynthetically active radiation distribution in maize canopy and stalk strength
    XUE Jun, GOU Ling, SHI Zhi-guo, ZHAO Ying-shan, ZHANG Wang-feng
    2017, 16(01): 85-96.  DOI: 10.1016/S2095-3119(16)61394-1
    Abstract ( )   PDF in ScienceDirect  
    The objectives of this study were to determine how the distribution of photosynthetically active radiation (PAR) in a maize canopy affected basal internode strength and stalk lodging.  The distributions of PAR within the canopies of two maize cultivars (Zhongdan 909 and Xinyu 41) were altered by removing whole leaves or half leaves in different canopy layers.  The results showed that removing whole leaves or half leaves above the three-ear-leaves (RAE and RAE/2) at flowering significantly increased PAR at the ear and interception of PAR (IPAR) from the ear to middle of the ear and soil surface.  These changes increased the structural carbohydrate content and rind penetration strength (RPS) of the third basal internode by 5.4–11.6% and reduced lodging by 4.2–7.8%.  Removal of the first three leaves below the three-ear-leaves (RBE) before flowering significantly reduced IPAR from the ear to half way below the ear.  This reduced the structural carbohydrate content and the RPS of the third basal internode by 9.1–17.4% and increased lodging by 7.0–11.2%.  Removal of the three lowest green leaves (RB) in the canopy before flowering increased PAR at the bottom of the canopy, but had no effect on the structural carbohydrate content of the basal internode, the RPS, and the lodging rate.  Overall, the results indicated that the key factors affecting the basal internode strength formation and lodging were PAR at the ear and IPAR from the ear to halfway below the ear.  Increasing PAR at the ear and IPAR from the ear to halfway below the ear could enhance lodging resistance by increasing the structural carbohydrate content and mechanical strength of the basal internode
    Effects of light intensity on leaf microstructure and growth of rape seedlings cultivated under a combination of red and blue LEDs
    YAO Xu-yang, LIU Xiao-ying, XU Zhi-gang, JIAO Xue-lei
    2017, 16(01): 97-105.  DOI: 10.1016/S2095-3119(16)61393-X
    Abstract ( )   PDF in ScienceDirect  
    The aim of this study was to evaluate the growth of rape (Brassica napus L.) seedlings under different light intensities to select appropriate conditions for cultivation in an indoor system.  Seedlings were grown under different light intensities of red and blue light provided by light-emitting diodes (LEDs) and their self-adjustment ability and changes in leaf microstructure were evaluated.  Light was supplied by red LEDs with peak wavelengths of 630 (R1) and 660 nm (R2) and by blue LEDs (B) with a peak wavelength of 445 nm (the light intensity ratio of R1:R2:B was 3:3:2), at intensities of 400 (R1R2B400), 300 (R1R2B300), and 200 μmol m–2 s–1 (R1R2B200).  Natural solar light served as the control (C).  Plant height, stem diameter, root length, leaf area, and dry weight of rape seedlings gradually increased with increasing light intensity.  The seedlings in the R1R2B400 treatment grew more vigorously, while those in the R1R2B200 treatment were weaker.  The photosynthetic pigment contents did not differ significantly between the R1R2B400 treatment and C, but were significantly lower in the R1R2B300 and R1R2B200 treatments.  The highest intercellular CO2 concentration, stomatal conductance, and transpiration rate were in the R1R2B300 treatment.  The highest photosynthetic rate was in the R1R2B400 treatment, and was related to more compact leaves, thicker and tidier palisade and spongy tissues, and well-developed chloroplasts.  In contrast, the seedlings in the R1R2B200 treatment had disordered mesophyll cells, round chloroplasts, and fractured and fuzzy grana lamellae, all of which inhibited plant growth.  In conclusion, the seedlings in the R1R2B400 treatment had well-developed leaves, which favored photosynthesis.  Compared with the light intensities below 300 μmol m–2 s–1, the light intensity of 400 μmol m–2 s–1 provided by a combination of red and blue LEDs was beneficial for cultivating strong and healthy rape seedlings in an artificial system.  
    Effects of different LED light wavelengths on the resistance of tomato against Botrytis cinerea and the corresponding physiological mechanisms
    XU Hui, FU Yan-nan, LI Tian-lai, WANG Rui
    2017, 16(01): 106-114.  DOI: 10.1016/S2095-3119(16)61435-1
    Abstract ( )   PDF in ScienceDirect  
    New types of light-emitting diode (LED) sources were applied to irradiate Botrytis cinerea mycelium and tomato leaves that were inoculated with B. cinerea to assess the effect of different LED light wavelengths on the infection of tomato with B. cinerea, to determine the optimum light wavelengths to control B. cinerea, and to explore the mechanism of LED influence on the development of gray mold.  The results showed that purple light and blue light irradiation significantly inhibited the growth of B. cinerea mycelium, and the inhibition rates were 22.3 and 15.16%, respectively, and purple light exhibited a better inhibitory effect than blue light.  The lesion development of B. cinerea on tomato leaves was significantly inhibited upon irradiation with red and purple light with inhibition rates of 32.08 and 36.74%, respectively.  Irradiation with red light inhibited the oxidative burst of superoxide anion (O2-.) that was caused by infection with B. cinerea, and red light regulated the H2O2 content in the tomato leaf, which increased and rapidly returned to a lower level.  In addition, red light irradiation improved the activity of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in tomato leaves.  However, purple light irradiation did not make tomato leaves exhibit this kind of physiological response.  Therefore, red light and purple light can suppress gray mold in tomatoes, but the disease suppression mechanisms of these two types of LED light are different.  In general, red light suppresses gray mold primarily by regulating the tomato defense mechanism for disease, whereas the suppression of tomato gray mold by purple light can be partially explained by the photo-inhibition of B. cinerea
    Plant Protection
    Development and detection application of monoclonal antibodies against Zucchini yellow mosaic virus
    CHEN Zhe, ZHANG Ming-hao, ZHOU Xue-ping, WU Jian-xiang
    2017, 16(01): 115-124.  DOI: 10.1016/S2095-3119(16)61416-8
    Abstract ( )   PDF in ScienceDirect  
    Aphid-borne Zucchini yellow mosaic virus (ZYMV) is one of the most economically important viruses of cucurbitaceous plants.  To survey and control this virus, it is necessary to develop an efficient detection technique.  Using purified ZYMV virion and the conventional hybridoma technology, three hybridoma cell lines (16A11, 5A7 and 3B8) secreting monoclonal antibodies (MAbs) against ZYMV Zhejiang isolate were obtained.  The working titers of the ascitic fluids secreted by the three hybridoma cell lines were up to 10–7 by indirect enzyme-linked immunosorbent assay (ELISA).  All MAbs were isotyped as IgG1, kappa light chain.  Western blot analysis indicated that the MAb 3B8 could specifically react with the coat protein of ZYMV while MAbs 5A7 and 16A11 reacted strongly with a protein of approximately 51 kDa from the ZYMV-infected leaf tissues.  According to this molecular weight, we consider this reactive protein is likely to be the HC-Pro protein.  Using these three MAbs, we have now developed five detection assays, i.e., antigen-coated-plate ELISA (ACP-ELISA), dot-ELISA, tissue blot-ELISA, double-antibody sandwich ELISA (DAS-ELISA), and immunocapture-RT-PCR (IC-RT-PCR), for the sensitive, specific, and easy detection of ZYMV.  The sensitivity test revealed that ZYMV could be readily detected respectively by ACP-ELISA, dot-ELISA, DAS-ELISA and IC-RT-PCR in 1:163 840, 1:2 560, 1:327 680 and 1:1 310 720 (w/v, g mL–1) diluted crude extracts from the ZYMV-infected plants.  We demonstrated in this study that the dot-ELISA could also be used to detect ZYMV in individual viruliferous aphids.  A total of 275 cucurbitaceous plant samples collected from the Zhejiang, Jiangsu, Shandong and Hainan provinces, China, were screened for the presence of ZYMV with the described assays.  Our results showed that 163 of the 275 samples (59%) were infected with ZYMV.  This finding indicates that ZYMV is now widely present in cucurbitaceous crops in China.  RT-PCR followed by DNA sequencing and sequence analyses confirmed the accuracy of the five assays.  We consider that these detection assays can significantly benefit the control of ZYMV in China.  
    Alleles contributing to acetyl coenzyme A carboxylase (ACCase) resistance in keng stiffgrass (Pseudosclerochloa kengiana) populations from China
    YUAN Guo-hui, GUO Wen-lei, DU Long, LIU Wei-tang, LI Qi, LI Ling-xu, WANG Jin-xin
    2017, 16(01): 125-134.  DOI: 10.1016/S2095-3119(16)61452-1
    Abstract ( )   PDF in ScienceDirect  
    Keng stiffgrass is a grass weed that affects wheat-rice cropping systems in China.  The extensive reliance on acetyl coenzyme A carboxylase (ACCase)-inhibiting herbicides has resulted in keng stiffgrass developing resistance to these herbicides.  The objective of this research was to evaluate the resistance level of the putative resistant keng stiffgrass populations to ACCase-inhibiting herbicides and to identify their molecular resistance mechanism.  Whole-plant dose-response experiments demonstrated that SD-4 (R), SD-11 (R), and JS-25 (R) populations were highly resistant to fenoxaprop, clodinafop, and fluazifop, moderately resistant to diclofop, had low resistance to sethoxydim and pinoxaden, but were sensitive to clethodim.  Partial chloroplastic ACCase sequences showed that there were two copies of ACCase gene in keng stiffgrass, and all homoeologous genes were expressed.  The results of sequence analyses of the ACCase CT domain revealed an isoleucine-to-asparagine substitution at position 2041 in SD-4 (R) and SD-11 (R) populations, and a tryptophan-to-cysteine substitution at position 2027 in the JS-25 (R) population.  To our knowledge, this is the first report of Ile-2041-Asn and Trp-2027-Cys mutations in ACCase-resistant keng stiffgrass.  In addition, three robust (derived) cleaved amplified polymorphic sequence ((d)CAPS) markers have been developed to rapidly identify these mutations in the ACCase gene of keng stiffgrass.
    Identification of similar transcriptional regulatory mechanisms in multiple cry genes in Bacillus thuringiensis HD12
    SONG Zhi-ru, PENG Qi, SHU Chang-long, ZHANG Jie, SUN Dong-mei, SONG Fu-ping
    2017, 16(01): 135-143.  DOI: 10.1016/S2095-3119(16)61398-9
    Abstract ( )  
    Bacillus thuringiensis subspecies morrisoni strain HD12, whose genome harbors multiple insecticidal protein-encoding genes, includes eight cry genes, as indicated by genome sequencing.  This strain produces crystals that are toxic to lepidopteran species.  These crystal inclusions were purified by sucrose gradients and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), followed by liquid chromatography-mass spectrometry, and found to contain five proteins (Cry1Da, Cry1Ae, Cry1Bb, Cry1Fb, and Cry1Ja).  The transcriptional activities of the cry1Da, cry1Ae, cry1Bb, cry1Fb, and cry1Ja promoters indicated that transcription of cry1Da is controlled by SigE; however, the other four cry genes were found to be controlled by both SigE and SigK.  The activities of the cry1Ja and cry1Fb promoters were the strongest among the five genes studied.  These promoters were therefore used to direct the expression of the Cry1Ac- and Cry2Ab-encoding genes concurrently in a single strain.  Our findings indicate that promoters with the same transcriptional profile may be used to direct the expression of different cry genes in one strain.  Our results are expected to be valuable for the construction of strains with efficient expression of multiple cry genes in order to overcome current limitations associated with the application of B. thuringiensis-based insecticides.
    Animal Science · Veterinary Science
    Wnt gene expression in adult porcine longissimus dorsi and its association with muscle fiber type, energy metabolism, and meat quality
    MEN Xiao-ming, DENG Bo, TAO Xin, QI Ke-ke, XU Zi-wei
    2017, 16(01): 144-150.  DOI: 10.1016/S2095-3119(16)61451-X
    Abstract ( )   PDF in ScienceDirect  
    This study investigated the expression profiles of Wnt genes in adult porcine longissimus dorsi (LD) from different porcine genotypes and their associations with meat quality.  The results showed that Wnt5a gene expression level was the highest in Jinhua (JHP) pigs, followed by Zhongbai (ZBP), Duroc×Zhongbai (DZB), and Duroc×Yorkshire×Landrace (DYL) pigs, with significant differences between ZBP, DZB, and DYL (P<0.05).  This genotypic order was reversed for Wnt7a, Wnt10b, and Wnt11 expression, with JHP and DYL having the lowest and highest expressive levels, respectively.  Wnt5a expression was negatively correlated with pH45 min and ΔpH (P<0.01), some glycolytic markers (P<0.05), and positively correlated with meat color (a*), shear force (SF) value (P<0.05), myosion heavy chain (MyHC) I mRNA proportion (P<0.01), turnover ratio of creatine phosphate (CP), and creatine kinase (CK) activity (P<0.05).  Opposite correlations were observed for Wnt2, Wnt7a, Wnt10b, and Wnt11.  These results revealed that Wnt5a, Wnt7a, Wnt10b, and Wnt11 gene expressions in adult porcine muscle contributed to differences between porcine genotypes and affected pork quality.  Wnt5a gene expression could be beneficial for the formation of high quality pork by regulating muscle fiber types and postmortem energy metabolism
    Indirect calorimetry to estimate energy requirements for growing and finishing Nellore bulls
    S L Posada-Ochoa, R R Noguera, N M Rodríguez, A L Costa, R Reis
    2017, 16(01): 151-161.  DOI: 10.1016/S2095-3119(16)61443-0
    Abstract ( )  
    Determination of nutritional requirements is the basis for diet formulation.  The objectives of this study were to determine the net energy requirements for maintenance (NEm) and weight gain (NEg) in Nellore bulls during the growing and finishing phases, and to estimate efficiency of metabolizable energy (ME) utilization for maintenance and gain (km, kg).  Five Nellore bulls were housed in individual pens at the Universidade Federal de Minas Gerais (Belo Horizonte, Brazil) and evaluated over four experimental periods at 210, 315, 378 and 454 kg shrunk body weight (SBW), approximately.  During each period, heat production (HP) was quantified by open circuit indirect calorimetry for three feeding levels: ad libitum, restricted and fasting.  The NEm requirement was determined by linear regression between the Log of HP and the ME intake (MEI) for the ad libitum and restricted levels.  This requirement was also determined by quantifying fasting heat production (FHP).  The NEg requirement was calculated by the difference between MEI and HP during ad libitum feeding.  The km and kg were calculated by the relationship between net energy (NE) and ME requirements for maintenance and weight gain (MEm, MEp), respectively.  The NEm requirements per kg of metabolic empty body weight (EBW0.75) fluctuated between 348 and 517 kJ d–1, showing a decreasing trend with age, and were higher than the values reported in the literature.  The NEg requirements ranged between 48.3 and 164 kJ kg–1 EBW0.75 d–1, and varied according to age and weight gain.  The km values varied between 58.6 and 69.7%, while kg varied between 23.4 and 40.2%.  We concluded that NEm and NEg requirements were influenced by age and possibly by the level of stress, nervousness and activity of animals into the respirometry chamber.  Further studies should quantify HP with records of positional changes (time spent standing vs. lying down).  Additionally, HP quantification should be repeatedly performed in the same experimental period to obtain a representative value of NEg requirements.
    Effects of sequence of nylon bags rumen incubation on kinetics of degradation in some commonly used feedstuffs in dairy rations
    DONG Shuang-zhao, Arash Azarfar, ZOU Yang, LI Sheng-li, WANG Ya-jing, CAO Zhi-jun
    2017, 16(01): 162-168.  DOI: 10.1016/S2095-3119(16)61438-7
    Abstract ( )   PDF in ScienceDirect  
    Nowadays, most available information on the degradative behaviour of feeds in ruminants is based on in situ incubation in the rumen, and it is adopted by many feed evaluation systems currently in use for ruminants.  However, the outcome of this technique might be affected by many factors such as sequence of nylon bags incubation in the rumen.  The objective of current study was to investigate effects of sequence of nylon bag incubation on degradative behavior of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) in some feed ingredients commonly used in dairy rations, including alfalfa haylage, corn silage, corn grain and soybean meal.  Four multiparous Holstein lactating cows fitted with permanent ruminal cannulas were used.  The nylon bags containing feed samples either were placed in the rumen at once and removed at designated time intervals (all in-gradually out method; AG) or were placed in the rumen at designated time points and retrieved at once (gradually in-all out method; GA).  Fractional rate of degradation of potentially degradable fraction, lag time and effective rumen degradability (ED) of DM and CP were significantly higher in the AG compared to the GA method (P<0.05).  Fractional rates of DM and CP degradation was higher in alfalfa haylage samples incubated in the rumen using the AG method compared to that using the GA method (0.138 h–1 vs. 0.073 h–1 and 0.002 h–1 vs. 0.1125 h–1, for DM and CP, respectively; P<0.05).  Due to a higher fractional rate of degradation (Kd) of DM and CP, the ED of DM and CP at different fractional passage rates were higher in the AG than those in the GA method (P<0.05).  Potentially degradable fraction and lag time of NDF were higher in the AG method compared to the GA method (P<0.05).  Placing all bags in the rumen at once and removing them at designated time intervals compared with introduction of bags in reverse sequence and removing them all at once led to a lower undegradable fraction (U) of NDF in alfalfa (1.8% vs. 4.0%, respectively; P<0.05) and corn silage (3.3% vs. 6.7%, respectively; P<0.05) samples.  Potentially degradable fraction of ADF was significantly higher in the AG method compared with the GA method (P<0.05).  Bag incubation sequence had profound effects on kinetics of degradation of DM, CP and NDF in situ in the feed samples studied.  The effects were more evident in the forages (especially alfalfa haylage) than in the concentrate ingredients
    PNPLA5-knockout rats induced by CRISPR/Cas9 exhibit abnormal bleeding and lipid level
    LIU Yang, GAO Qian, ZHANG Xue, HUANG Lei, XU Kui, HU Yan-qing, LIU Lan, MU Yu-lian, LI Kui
    2017, 16(01): 169-180.  DOI: 10.1016/S2095-3119(16)61437-5
    Abstract ( )   PDF in ScienceDirect  
    Patatin-like phospholipase domain containing 5 (PNPLA5) is a neotype neutral lipase with dual activity of anabolism and catabolism in vitro and in vivo, which has a low mRNA expression level in humans and mice.  PNPLA5, which is localized to lipid droplets and required for efficient autophagy by optimal initiation, has been speculated to possess triglyceride hydrolase activity, and has been associated with low density lipoprotein cholesterol (LDL-C).  Above all, PNPLA5 is a relatively new gene, which is reported less about its biological function research, especially the function research in the rats is still blank.  In this study, we examined the spatiotemporal expression profile of PNPLA5 and found that it was expressed at low levels in most organs of Sprague Dawley (SD) rats, but was present at very high levels in the skin and testes.  To further determine the biological function of PNPLA5 in mammals, we generated PNPLA5-knockout SD rats using the clustered regularly-interspaced short palindromic repeats (CRISPR)/Cas9 system.  PNPLA5-null rats were viable, but showed a variety of phenotypic abnormalities, such as abnormal bleeding, and varied hematobiochemical parameters including increased serum total cholesterol (TC), triglycerides and high density lipoprotein cholesterol (HDL-C) level, and reduced LDL-C level, compared with wild-type control rats.  These data are consistent with an important role for PNPLA5 in lipid metabolism, providing a new target gene and animal model for treatment of cardiovascular diseases in the future.
    Adoption of HPAI biosecurity measures: The Chinese broiler industry
    HUANG Ze-ying, Adam Loch, Christopher Findlay, WANG Ji-min
    2017, 16(01): 181-189.  DOI: 10.1016/S2095-3119(16)61511-3
    Abstract ( )   PDF in ScienceDirect  
    Highly pathogenic avian influenza (HPAI) contamination via wild birds and rodents poses a threat to food security and safety.  As chicken meat comprises an increasing proportion of diet in China, it is useful to determine whether broiler farmers are adopting wild bird and rodent controls to minimize the risk of HPAI impacts on food supply.  Our study surveyed a cross sectional sample of 331 Chinese broiler farmers in six provinces.  We find that only 47% of farmers (mainly farmers with large herds) adopted control measures against wild birds and rodents, while 14% adopted no measures.  Farm size was the biggest driver of adoption followed by proportion of farm revenue derived from broiler production.  However, southern farmers were at a far greater probability of non-adoption.  We suggest that assistance in the form of education/training programs and subsidized traps or baiting controls across smaller producers could help raise of the adoption level toward more effective HPAI control.
    Soil & Fertilization﹒Irrigation﹒Plant Nutrition﹒ Agro-Ecology & Environment
    Nitrogen (N) metabolism related enzyme activities, cell ultrastructure and nutrient contents as affected by N level and barley genotype
    Jawad Munawar Shah, Syed Asad Hussain Bukhari, ZENG Jian-bin, QUAN Xiao-yan, Essa Ali, Noor Muhammad, ZHANG Guo-ping
    2017, 16(01): 190-198.  DOI: 10.1016/S2095-3119(15)61308-9
    Abstract ( )   PDF in ScienceDirect  
    Development of the new crop cultivars with high yield under low nitrogen (N) input is a fundamental approach to enhance agricultural sustainability, which is dependent on the exploitation of the elite germplasm.  In the present study, four barley genotypes (two Tibetan wild and two cultivated), differing in N use efficiency (NUE), were characterized for their physiological and biochemical responses to different N levels.  Higher N levels significantly increased the contents of other essential nutrients (P, K, Ca, Fe, Cu and Mn), and the increase was more obvious for the N-efficient genotypes (ZD9 and XZ149).  The observation of ultrastructure showed that chloroplast structure was severely damaged under low nitrogen, and the two high N efficient genotypes were relatively less affected.  The activities of the five N metabolism related enzymes, i.e.,  nitrate reductase (NR), glutamine synthetase (GS), nitrite reductase (NiR), glutamate synthase (GOGAT) and glutamate dehydrogenase (GDH) all showed the substantial increase with the increased N level in the culture medium.  However the increased extent differed among the four genotypes, with the two N efficient genotypes showing more increase in comparison with the other two genotypes with relative N inefficiency (HXRL and XZ56).  The current findings showed that a huge difference exists in low N tolerance among barley genotypes, and improvement of some physiological traits (such as enzymes) could be helpful for increasing N utilization efficiency. 
    Effective remediation of aged HMW-PAHs polluted agricultural soil by the combination of Fusarium sp. and smooth bromegrass (Bromus inermis Leyss.)
    SHI Wei, ZHANG Xue-na, JIA Hai-bin, FENG Sheng-dong, YANG Zhi-xin, ZHAO Ou-ya, LI Yu-ling
    2017, 16(01): 199-209.  DOI: 10.1016/S2095-3119(16)61373-4
    Abstract ( )   PDF in ScienceDirect  
    Fusarium sp. strain ZH-H2 is capable to degrade high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs),  smooth bromegrass (Bromus inermis Leyss.) can also degrade 4- to 6-ring PAHs.  Pot experiments were conducted to investigate how bromegrass and different inoculum sizes of ZH-H2 clean up HMW-PAHs in agricultural soil derived from a coal mine area.  The results showed that, compared with control, different sizes of inocula of ZH-H2 effectively degraded HMW-PAHs, with removal rates of 19.01, 34.25 and 29.26% for 4-, 5- and 6-ring PAHs in the treatment with 1.0 g kg–1 ZH-H2 incubation after 90 d.  After 5 mon of cultivation, bromegrass reached degradation rate of these compounds by 12.66, 36.26 and 36.24%, respectively.  By adding strain ZH-H2 to bromegrass, HMW-PAHs degradation was further improved up to 4.24 times greater than bromegrass (W), in addition to the degradation rate of Bbf decrease.  For removal rates of both 5- and 6-ring PAHs, addition of 0.5 g kg–1 Fusarium ZH-H2 to pots with bromegrass performed better than addition of 0.1 g kg–1, while the highest concentration of 1.0 g kg–1 Fusarium ZH-H2 did not further improve degradation.  Degradation of 4-ring PAHs showed no significant difference among different ZH-H2 incubations with bromegrass treatments.  We found that the degradation rates of 4-, 5- and 6-ring PAHs in all treatments are significantly correlated in a positive, linear manner with activity of lignin peroxidase (LiP) (r=0.8065, 0.9350 and 0.9165, respectively), while degradation of 5- and 6-ring PAHs is correlated to polyphenoloxidase (PPO) activity (r=0.7577 and 07806).  Our findings suggest that the combination of Fusarium sp. ZH-H2 and bromegrass offers a suitable alternative for phytoremediation of aged PAH-contaminated soil in coal mining areas, with a recommended inoculation size of 0.5 g Fusarium sp. ZH-H2 per kg soil.
    Towards a more flexible representation of water stress effects in the nonlinear Jarvis model
    YU Lian-yu, CAI Huan-jie, ZHENG Zhen, LI Zhi-jun, WANG Jian
    2017, 16(01): 210-220.  DOI: 10.1016/S2095-3119(15)61307-7
    Abstract ( )   PDF in ScienceDirect  
    To better interpret summer maize stomatal conductance (gs) variation under conditions of changing water status at different growth stages, three water stress indicators, soil water content (SWC), leaf-air temperature difference (?T) and leaf level water stress index (CWSIL) were employed in Jarvis model, which were JS, JT and JC models respectively.  Measurements of gs were conducted in a summer maize field experiment during the year 2012–2013.  In the insufficient irrigation experiment, three levels of irrigation amount were applied at four different growth stages of summer maize.  We constructed three scenarios to evaluate the performance of the three water stress indicators for estimating maize gs in a modified Jarvis model.  Results showed that JT and JC models had better simulation accuracy than the JS model, especially at the late growth stage (Scenario 1) or considering the plant recovery compensation effects (Scenario 2).  Scenario 3 indicated that the more environmental factors were adopted, the better prediction performance would be for JS model.  While for JT model, two environmental factors (photosynthesis active radiation (PAR), and vapor pressure deficit (VPD)) seemed good enough to obtain a reliable simulation.  When there were insufficient environmental data, CWSIL would be the best option.  This study can be useful to understand the response of plant stomatal to changing water conditions and will further facilitate the application of the Jarvis model in various environments.
    Greenhouse gas emissions from pig and poultry production sectors in China from 1960 to 2010       
    WANG Li-zhi, XUE Bai, Tianhai Yan
    2017, 16(01): 221-228.  DOI: 10.1016/S2095-3119(16)61372-2
    Abstract ( )   PDF in ScienceDirect  
    Pig and poultry production in China had experienced considerable changes from 1960 to 2010.  The present study aimed to evaluate the effects of these changes on greenhouse gas emission inventories (expressed as CO2 equivalent) from these two sectors.  The inventories included methane emissions from enteric fermentation, methane and nitrous oxide production from manure management.  The greenhouse gas emissions from these sources in 2010 in pig sector were 17, 62 and 21%, respectively, and that in poultry sector (including chicken, duck, goose and others) were 1, 18 and 81%, respectively.  Total CO2 equivalent increased from 1960 to 2010 in both pig (11 582 to 55 564 Gg yr–1) and poultry (1 497 to 14 873 Gg yr–1) sectors.  Within poultry sector, emissions from chicken, duck, goose and others accounted for 74, 15, 11 and 0.01% in 2010, respectively.  However, during the last 50 years, these emissions continuously reduced when related to production of 1 kg of pork (8.01 to 1.14 kg kg–1), poultry meat (1.19 to 0.37 kg kg–1) and egg (0.47 to 0.33 kg kg–1), which is mainly associated with the continuous improvement in production efficiency in all management systems.  These results provide benchmark information for Chinese authorities to develop appropriate policies and mitigation strategies to reduce greenhouse gas emissions from pig and poultry sectors.
    The renewability and quality of shallow groundwater in Sanjiang and Songnen Plain, Northeast China
    ZHANG Bing, SONG Xian-fang, ZHANG Ying-hua, HAN Dong-mei, TANG Chang-yuan, YANG Li-hu, WANG Zhong-liang
    2017, 16(01): 229-238.  DOI: 10.1016/S2095-3119(16)61349-7
    Abstract ( )   PDF in ScienceDirect  
    Groundwater is a key component for water resources in Sanjiang and Songnen Plain, an important agriculture basement in China.  The quality and the renewability of irrigation groundwater are essential for the stock raising and agricultural production.  Shallow groundwater was sampled and analyzed for various variables.  The salinity sodium concentration and bicarbonate hazard, were examined with regard to the United States Department of Agriculture (USDA) irrigation water standards.  The concentration of chlorofluorocarbons (CFCs) was determined to analyze the age of groundwater.  Most groundwater samples labeled as excellent to good for irrigation with low salinity hazard or medium salinity hazard.  Four groundwater samples were good and suspected for irrigation with high salinity hazard.  Generally groundwater in Sanjiang Plain was younger than the groundwater in Songnen Plain.  Meanwhile, groundwater nearby river is younger than the groundwater further away inside the watershed.  The mean age of groundwater in Sanjiang Plain is in average of 44.1, 47.9 and 32.8 years by CFC-11 (CCl3F), CFC-12 (CCl2F2) and CFC-113 (C2Cl3F3),  respectively.  The mean ages of groundwater in Songnen Plain is in average of 46.1, 53.4, and 40.7 years by CFC-11, CFC-12 and CFC-113, respectively.  Thus, groundwater nearby rivers could be directly exploited as irrigation water.  Partial groundwater has to be processed to lower the salt concentration rather than directly utilized as irrigation water in Songnen Plain.  Both water quality and renewability should be put in mind for sustainable agricultural development and water resources management.