Sun H.Y.,Northwest University, China |
Sun H.Y.,Institute of Soil Ecology |
Wang C.X.,Northwest University, China |
Wang C.X.,Hainan Academy of Agricultural Science |
And 2 more authors.
Soil Use and Management | Year: 2013
Over the past 20 years, conservation tillage has been used on the loess plateau of north-west China to improve the sustainability of local agriculture. There had been particular concern about loss of soil organic matter associated with traditional tillage. We examined the influence of four tillage treatments: conventional tillage (CT), subsoiling tillage (SST), rotary tillage (RT) and no-tillage (NT), with two straw residue management treatments (return and removal) on the distribution with soil depth (0-20 cm, 20-40 cm) of total organic carbon, labile organic carbon (KMnO4-C) and bound organic carbon. The study was carried out on a Loutu soil (Earth-cumuli-Orthic Anthrosol) over seven consecutive years of a winter wheat (Triticum aestivum L.)-summer maize (Zea mays L.) crop rotation. By the end of this period, conservation tillage (SST, RT and NT) led to greater storage of soil organic carbon (SOC) (22.7, 14.9 and 16.3% with straw return in contrast to 21.4, 15.8 and 12.3% with no straw return, respectively) compared with CT in the surface soil (0-20 cm). The reduced tillage treatments (SST and RT) both increased significantly the highly labile organic carbon (HLOC) content of the surface soil (50% in both SST and RT) and mildly labile organic matter (MLOC) (49.4 in SST and 53.5% in RT) when straw was removed. The largest pool of bound carbon was observed in the Humin-C pool, and the smallest in the free humic acids C (FHA-C) in each tillage treatment. Conservation tillage led to an increased content of FHA-C and CHA-C. Results from correlation analyses indicate that SOC enrichment might have resulted from the increase in HLOC, MLOC, FHA-C and CHA-C over a short period. Labile organic carbon was associated with the organic carbon that was more loosely combined with clay (FHA-C and CHA-C). We conclude that both SST and RT are effective in maintaining or restoring organic matter in Loutu soils in this region, and the effect is greater when they are used in combination with straw return. © 2013 British Society of Soil Science.
Zhai J.,Hainan University |
Luo Y.,Hainan University |
Zheng D.,Hainan Academy of Agricultural Science |
Huang X.,Hainan University
Journal of Phytopathology | Year: 2010
Highly virulent strains (HVSs) of Xanthomonas campestris pv. malvacearum (Xcm) infect all commercial cultivars of cotton including the resistant cultivar '101-102B'. Previous reports showed that different HVS isolates caused distinct symptoms on host. To evaluate the global genetic diversity of Xcm as well as HVS, 38 strains including 12 HVSs isolated from different countries were analysed by repetitive sequence (rep)-based PCR with ERIC and BOX primer sets. rep-PCR showed abundant polymorphism of fingerprinting. The strains were separated into different genotypic groups at a similarity coefficient of 0.76 using a UPGMA analysis. Interestingly, the strains with low or moderate virulence were clustered in one genogroup, whereas all HVSs isolated in Africa were segregated in another genogroup. These results suggest that the virulence of Xcm was highly related to genotype and/or geoclimatic origin of the strains. Additionally, the HVSs could be divided into two subgroups at a similarity coefficient of 0.80, indicating the genetic diversity of HVSs. © 2010 Blackwell Verlag GmbH.
PubMed | REPUBLIC RESOURCES and Hainan Academy of Agricultural science
Type: Journal Article | Journal: Plant cell reports | Year: 2016
SpAQP1 was strongly induced by salt in an ABA-independent way, promoted seed germination and root growth in transgenic tobaccos and increased salt tolerance by increasing the activities of antioxidative enzymes. Aquaporin (AQP) plays crucial roles in the responses of plant to abiotic stresses such as drought, salt and cold. Compared to glycophytes, halophytes often have excellent salt and drought tolerances. To uncover the molecular mechanism of halophyte Sesuvium portulacastrum tolerance to salt, in this study, an AQP gene, SpAQP1, from S. portulacastrum was isolated and characterized. The amino acid sequence of SpAQP1 shared high homology with that of plant plasma membrane intrinsic proteins (PIPs) and contained the distinct molecular features of PIPs. In the phylogenic tree, SpAQP1 was evidently classified as the PIP2 subfamily. SpAQP1 is expressed in roots, stems and leaves, and was significantly induced by NaCl treatment and inhibited by abscisic acid (ABA) treatment. When heterologously expressed in yeast and tobacco, SpAQP1 enhanced the salt tolerance of yeast strains and tobacco plants and promoted seed germination and root growth under salt stress in transgenic plants. The activity of antioxidative enzymes including superoxide dismutase, peroxidase and catalase was increased in transgenic plants overexpressing SpAQP1. Taken together, our studies suggested that SpAQP1 functioned in the responses of S. portulacastrum to salt stress and could increase salt tolerance by enhancing the antioxidative activity of plants.
Xie L.,Guangdong Provincial Key Laboratory of Agro Animal Genomics and Molecular Breeding |
Xie L.,Hainan Academy of Agricultural science |
Luo C.,Guangdong Provincial Key Laboratory of Agro Animal Genomics and Molecular Breeding |
Luo C.,State Key Laboratory of Livestock and Poultry Breeding |
And 9 more authors.
PLoS ONE | Year: 2012
Chicken growth traits are important economic traits in broilers. A large number of studies are available on finding genetic factors affecting chicken growth. However, most of these studies identified chromosome regions containing putative quantitative trait loci and finding causal mutations is still a challenge. In this genome-wide association study (GWAS), we identified a narrow 1.5 Mb region (173.5-175 Mb) of chicken (Gallus gallus) chromosome (GGA) 1 to be strongly associated with chicken growth using 47,678 SNPs and 489 F2 chickens. The growth traits included aggregate body weight (BW) at 0-90 d of age measured weekly, biweekly average daily gains (ADG) derived from weekly body weight, and breast muscle weight (BMW), leg muscle weight (LMW) and wing weight (WW) at 90 d of age. Five SNPs in the 1.5 Mb KPNA3-FOXO1A region at GGA1 had the highest significant effects for all growth traits in this study, including a SNP at 8.9 Kb upstream of FOXO1A for BW at 22-48 d and 70 d, a SNP at 1.9 Kb downstream of FOXO1A for WW, a SNP at 20.9 Kb downstream of ENSGALG00000022732 for ADG at 29-42 d, a SNP in INTS6 for BW at 90 d, and a SNP in KPNA3 for BMW and LMW. The 1.5 Mb KPNA3-FOXO1A region contained two microRNA genes that could bind to messenger ribonucleic acid (mRNA) of IGF1, FOXO1A and KPNA3. It was further indicated that the 1.5 Mb GGA1 region had the strongest effects on chicken growth during 22-42 d. © 2012 Xie et al.
Shi M.,University of Tsukuba |
Shi M.,Hainan Academy of Agricultural science |
Zhang Z.,University of Tsukuba |
Yang Y.,University of Tsukuba
Carbohydrate Polymers | Year: 2013
Four polysaccharides (GLP-I, GLP-II, GLP-III and GLP-IV) were obtained from fermented soybean curd residue by Ganoderma lucidum, and then purified using anion-exchange DEAE Sephadex A-50. Their structural characterization was conducted by Fourier transform infrared spectroscopy (FTIR), and their monosaccharide compositions were determined. The results demonstrated that the basic structural characterization of four polysaccharides were similar, however, monosaccharide compositions of four kinds of polysaccharides were significant difference. GLP-III and GLP-IV were composed of six kinds of monosaccharide. Nevertheless, GLP-II was composed of three kinds of monosaccharide. Moreover, their antioxidant activities were investigated on the basis of hydroxyl radical, reducing power, DPPH free radical, chelating activity, ABTS radical-scavenging and SOD-like activity. The results showed that four polysaccharides exhibited antioxidant activities in a concentration-dependent manner. Among four polysaccharides, GLP-III and GLP-IV exhibited the higher scavenging effects on hydroxyl radicals, ABTS radical, DPPH free radical, and stronger reducing power and SOD-like activity than GLP-I and GLP-II. In addition, treatment with 40 μg/mL of GLP showed significant stimulation to the macrophage proliferation and higher nitric oxide production. Overall, GLP from fermented SCR could have potential applications in the medical and food industries.
Low genetic diversity and local adaptive divergence of Dracaena cambodiana (Liliaceae) populations associated with historical population bottlenecks and natural selection: An endangered long-lived tree endemic to Hainan Island, China
Zheng D.-J.,Hainan Academy of Agricultural science |
Zheng D.-J.,Chinese Academy of Sciences |
Xie L.-S.,Hainan Academy of Agricultural science |
Zhu J.-H.,Chinese Academy of Sciences |
And 2 more authors.
Plant Biology | Year: 2012
Historical population bottlenecks and natural selection have important effects on the current genetic diversity and structure of long-lived trees. Dracaena cambodiana is an endangered, long-lived tree endemic to Hainan Island, China. Our field investigations showed that only 10 populations remain on Hainan Island and that almost all have been seriously isolated and grow in distinct habitats. A considerable amount of genetic variation at the species level, but little variation at the population level, and a high level of genetic differentiation among the populations with limited gene flow in D. cambodiana were detected using inter-simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD) analyses. No significant correlation was found between genetic diversity and actual population size, as the genetic diversities were similar regardless of population size. The Mantel test revealed that there was no correlation between genetic and geographic distances among the 10 populations. The UPGMA, PCoA and Bayesian analyses showed that local adaptive divergence has occurred among the D. cambodiana populations, which was further supported by habitat-private fragments. We suggest that the current genetic diversity and population differentiation of D. cambodiana resulted from historical population bottlenecks and natural selection followed by historical isolation. However, the lack of natural regeneration of D. cambodiana indicates that former local adaptations with low genetic diversity may have been genetically weak and are unable to adapt to the current ecological environments. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.
Zhu J.,Chinese Academy of Sciences |
Zhang Q.,Chinese Academy of Sciences |
Wu R.,Chinese Academy of Sciences |
Zhang Z.,Chinese Academy of Sciences |
Zhang Z.,Hainan Academy of Agricultural science
Plant Physiology and Biochemistry | Year: 2010
Metallothioneins (MTs) are the cysteine-rich proteins with low molecular weight, which play important roles in maintaining intracellular ion homeostasis, detoxification of heavy metal ions and protecting against intracellular oxidative damages. In this study a novel ethephon-induced metallothionein gene, designated as HbMT2, was isolated and characterized from Hevea brasiliensis. The HbMT2 cDNA contained a 237 bp open reading frame encoding 78 amino acids and the deduced protein showed high similarity to the type 2 MTs from other plant species. Expression analysis revealed more significant accumulation of HbMT2 transcripts in leaves and latex than in roots and barks. The transcription of HbMT2 in latex was strongly induced by ethephon and hydrogen peroxide (H2O2) stress. Overproduction of recombinant HbMT2 protein gave the Escherichia coli cells more tolerance on Cu2+ and Zn2+, and the recombinant HbMT2 could scavenge the reactive oxidant species (ROS) in vitro. All these results indicated that HbMT2 could respond to ethephon stimulation and H2O2 stress as a ROS scavenger in H. brasiliensis. It is also suggested that HbMT2 function in improving the tolerance of rubber trees to heavy metal ions, and repressing the ethephon-induced senilism and tapping panel dryness (TPD) development by ROS scavenge system in H. brasiliensis. © 2010 Elsevier Masson SAS.
Quan R.,Chinese Academy of Agricultural Sciences |
Quan R.,National Center for Plant Gene Research Beijing |
Hu S.,Chinese Academy of Agricultural Sciences |
Hu S.,Hainan Academy of Agricultural science |
And 7 more authors.
Plant Biotechnology Journal | Year: 2010
One of the major limitations in rice production is a shortage of water. Conventional breeding as well as emerging genetic engineering methods may be used to improve plant stress tolerance. Some transcription factors regulating stress responsive genes have become important target genes for improving plant drought tolerance. Previously, we have shown that a tomato ethylene response factor (ERF) protein TSRF1 that binds to GCC box in the promoters of pathogenesis-related genes positively regulates pathogen resistance in tomato and tobacco, but negatively regulates osmotic response in tobacco. Here, we further report the ability of TSRF1 to regulate osmotic and drought responses in monocot rice. TSRF1 improves the osmotic and drought tolerance of rice seedlings without growth retardation, as determined by physiological analyses of root and leaf growth, leaf water loss and survival rate under stress. In addition, the amounts of proline and soluble sugars in transgenic rice lines increase by 30%-60% compared to those in wild-type plants. Moreover, TSRF1 activates the expression of a putative rice abscisic acid (ABA) synthesis gene SDR, resulting in enhanced ABA sensitivity in transgenic rice. TSRF1 also increases the expression of MYB, MYC and proline synthesis and photosynthesis-related genes, probably by binding to dehydration responsive element and GCC boxes in promoters of the target genes. These results demonstrate that TSRF1 enhances the osmotic and drought tolerance of rice by modulating the increase in stress responsive gene expression. © 2010 Blackwell Publishing Ltd.
Wei Y.-Z.,South China Agricultural University |
Wei Y.-Z.,Chinese Academy of Sciences |
Hu F.-C.,South China Agricultural University |
Hu F.-C.,Hainan Academy of Agricultural science |
And 4 more authors.
PLoS ONE | Year: 2011
Litchi has diverse fruit color phenotypes, yet no research reflects the biochemical background of this diversity. In this study, we evaluated 12 litchi cultivars for chromatic parameters and pigments, and investigated the effects of abscisic acid, forchlorofenron (CPPU), bagging and debagging treatments on fruit coloration in cv. Feizixiao, an unevenly red cultivar. Six genes encoding chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), anthocyanidin synthase (ANS) and UDP-glucose: flavonoid 3-O-glucosyltransferase (UFGT) were isolated from the pericarp of the fully red litchi cv. Nuomici, and their expression was analyzed in different cultivars and under the above mentioned treatments. Pericarp anthocyanin concentration varied from none to 734 mg m-2 among the 12 litchi cultivars, which were divided into three coloration types, i.e. non-red ('Kuixingqingpitian', 'Xingqiumili', 'Yamulong'and 'Yongxing No. 2′), unevenly red ('Feizixiao' and 'Sanyuehong') and fully red ('Meiguili', 'Baila', Baitangying' 'Guiwei', 'Nuomici' and 'Guinuo'). The fully red type cultivars had different levels of anthocyanin but with the same composition. The expression of the six genes, especially LcF3H, LcDFR, LcANS and LcUFGT, in the pericarp of non-red cultivars was much weaker as compared to those red cultivars. Their expression, LcDFR and LcUFGT in particular, was positively correlated with anthocyanin concentrations in the pericarp. These results suggest the late genes in the anthocyanin biosynthetic pathway were coordinately expressed during red coloration of litchi fruits. Low expression of these genes resulted in absence or extremely low anthocyanin accumulation in non-red cultivars. Zero-red pericarp from either immature or CPPU treated fruits appeared to be lacking in anthocyanins due to the absence of UFGT expression. Among these six genes, only the expression of UFGT was found significantly correlated with the pericarp anthocyanin concentration (r = 0.84). These results suggest that UFGT played a predominant role in the anthocyanin accumulation in litchi as well as pericarp coloration of a given cultivar. © 2011 Wei et al.
Tang L.-D.,Chinese Academy of Sciences |
Lu Y.-Y.,South China Agricultural University |
Zhao H.-Y.,Hainan Academy of Agricultural science
Environmental Entomology | Year: 2015
Spalangia endius (Walker) (Hymenoptera: Pteromalidae) is found to be one of the most important natural enemies of Bactrocera dorsalis Hendel (Diptera: Tephritidae) pupae in China. In this study, the influence of host pupal age on the preference for and suitability of the host by the parasitoid S. endius was determined using choice and nonchoice tests. S. endius females accepted the 1-7 d-old B. dorsalis pupae for oviposition, and their offspring developed successfully. However, the S. endius preferentially parasitized the 2-, 3-, and 4-d-old host pupae. The emergence rate of the adult progeny was not affected by the host pupal age, nor was the male body weight, male longevity, and sex ratio of the parasitoid offspring. However, the shortest development time of both male and female progeny and the greatest size and adult longevity of female progeny were observed in hosts that were ≤4 d old. Females emerged later and lived longer than males, and they weighed more than the males. Host mortality decreased as the age of the host increased for 1-7-d-old hosts. Our findings suggest that 2-, 3-, and 4-d-old B. dorsalis pupae would be the best host ages at which to rear S. endius for effective control in field releases. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved.