Abstract:In order to study the application of aroma substances GC/MS fingerprint in the quality control of flue-cured tobacco, the Nanping flue-cured tobaccoes were grouped into 3 grades—medium, medium+ and better—according to the sensory evaluation, and the corresponding standard fingerprints of the three grades flue-cured tobacco were established. The fingerprint similarity of each sample with standard fingerprint was calculated. The high values indicated the high similarity, threshold of the three grades were defined according to the similarity of the fingerprint, which were 0.731 2, 0.703 6 and 0.676 7 respectively. Pattern recognization of the three grades flue-cured tobacco was carried out by projection drawing of principal constituent analysis. Pattern recognization results showed the good spatial distribution in the chart, obvious section, which indicated the feasibility and resolution of the quality control system.The unknown samples were used to test the effectiveness of the quality control system. The result indicated that the system had high accuracy, low error rate, and adaptability to the quality control of flue-cured tobacco.

Abstract:The influences of ABA (600 mg/L), GA₃ (30 mg/L) and NAA (200 mg/L) treatments on the fruit growth and the contents of anthocyanins, phenolics, sugars and flavonoids in blueberry，Vaccinium cv. Bluecrop，were studied. The results showed that during the period from veraison to full maturity, there were marked positive correlations between the contents of anthocyanins and hexoses and a negative correlation between contents of anthocyanins and flavonoids. Compared with the control, ABA treatment promoted fruit softening and significantly increased the contents of anthocyanins (3.01 mg/g), fructose (13.22 mg/g) and glucose (35.51 mg/g) in fruit; NAA treatment significantly reduced the fruit weight and suppressed the accumulation of total phenols and flavonoids; GA₃ treatment significantly increased fruit mass and the content of soluble solids. Both NAA and GA₃ treatment reduced the accumulation of anthocyanins, but the effect was not significant, and the final content was 2.29 mg/g.

Abstract:By using a four-year old Ningqi NO.1 as the tested material, different amounts of biogas liquid manure (0, 6, 8, 10, 12, 14 kg per plant) were applied to study their effects on the growth, quality and yield with a random block experimental design. The results showed that the application of biogas liquid manure not only increased the aboveground biomass, leaf area index and chlorophyll content， but also enhanced the 100-seed mass, yield, polysaccharide, carotenoid, flavonoid and betaine content in the fruits. There were significant variations in different treatments. Spring shoot growth rates increased first and decreased afterwards. Leaf area and biomass peaked under the treatment of 10 kg per plant. With the increase of the application of biogas liquid manure, chlorophyll content presented an obviously rose and tended to be stable when the application of biogas liquid manure was higher than 12 kg per plant. Polysaccharides and betaine content reached maximum value under 10 and 12 kg per plant respectively. Carotenoid content and dried fruit mass increased while flavonoid content did not increase with application of biogas liquid manure, and the dried fruit mass of aplication of biogas liquid manure 10 kg per plant tended to be stable. The combination of the existing fertilization with the application of biogas liquid manure 10 kg per plant had significant effects on the growth, quality and grain yield.

Abstract:Nutrient abundance and deficiency and fertilization recommendation index of balsam pear were established in Guangdong. Data analysis were based on the “3414”field experiments of trail in Guangdong from 2002 to 2011. Taking plentiful-lack of soil nutrition as an index, soil alkali hydrolyzable nitrogen (N), Olsen-P and available potassium were classified into five classes corresponding to relative yield of 50%,75%,90%and 95%. Fertilizer recommended rates were simulated by the models of one-factor, liner and platform for “3414”field experiments. The results showed that nitrogen fertilizer(N) rates (kg·hm^-2) were 300≤y₁<390, 200≤y₁<300, 140≤y₁<200, 120≤y₁<140, and0< y₁<120 when soil fertilizer was classified as very low, low, medium, high and the highest［w(N)≤70 mg·kg^-1, 70 mg·kg^-1< w(N)≤120 mg·k^-1, 120 mg·kg^-1< w(N)≤165 mg·kg^-1, 165 mg·kg^-1< w(N)≤185 mg·kg^-1 and w(N)>185 mg·kg^-1］, respectively; phosphorus fertilizer (P₂O₅) rates(kg·hm^-2) were 200≤y₂<215, 120≤y₂<200, 80≤y₂<120, 65≤y₂<80 and 0<y₂<65［w(P₂O₅)≤5 mg·kg^-1, 5 mg·kg^-1< w(P₂O₅)≤35 mg·kg^-1, 35 mg·kg^-1< w(P₂O₅)≤95 mg·kg^-1, 95 mg·kg^-1< w(P₂O₅)≤140 mg·kg^-1 and w(P₂O₅)>140 mg·kg^-1］,while potassium fertilizer (K₂O) rates(kg·hm^-2)were 275≤y₃<372, 175≤y₃<275, 110≤y₃<175, 90≤y₃<110 and 0< y₃<90［w(K₂O)<30 mg·kg^-1, 30 mg·kg^-1< w(K₂O)≤85 mg·kg^-1, 85 mg·kg^-1< w(K₂O)≤165 mg·kg^-1, 165 mg·kg^-1<w(K₂O)≤200 mg·kg^-1and w(K₂O)>200 mg·kg^-1］. Compared with the fertilization plentiful-lack index by original system, the soil nutrition content of this research suggested that nitrogen, phosphorus and potassium increased.

Abstract:Banana soft rot, a serious disease caused by Dickeya sp., was found in Guangdong and Hainan provinces. The host range of banana soft rot pathogens in China and the disease resistance of different banana varieties were not reported. Three isolates of banana soft rot pathogens and 22 species of plants from 15 families were investigated for pathogen-host range by using artificial inoculation methods. The results indicated that three isolates had a wide host range. In addition, seven banana varieties, which widely grew in China, were used to identify the resistance to banana soft rot. The results showed that Musa AA Pisang Mas had a high resistance; Musa AAA Cavendish cv. Brazil, Musa AAA Cavendish cv. Nongke No.1, and Musa ABB Pisang had a moderate resistance; Musa ABB Pisang Awak cv. Jinfen, Musa AAA Cavendish cv. Williams, Musa ABB Pisang Awak cv. Guangfen were moderately susceptible.

Abstract:Five fungicides, namely 50% carbendazin WP, 80% mancozeb WP, 10% difenoconazole WG, 45% prochloraz EW and 25% azoxystrobin FW, were tested for their toxicities to citrus anthracnose pathogen Colletotrichum gloeosporioides isolates from different cirtrus varieties and different districts of Guangdong Province by using mycelial growth rate method. The results showed that prochloraz had the best antifungal effect, followed by difenoconazole. All tested isolates had certain degrees of resistance to azoxystrobin and mancozeb, and showed obvious sensitivity differences to carbendazim. Isolates CCMZ004, CCMZ004, CCST003 and CCST026 all had the strong tolerance (resistance) to carbendazim.Therefore, prochloraz and difenoconazole can be used as the preferable fungicides to control citrus anthracnose.

Abstract:The flash point, volatility, pesticide solubility and stability of the pine oleoresin-based plant oils were measured for the purpose of development of natural alternatives of aromatic solvents in pesticide formulation. The results showed that the flash points of the 4 types of pine oleoresin-based plant oils were all above 35 ℃, which were obviously higher than that of the control solvent xylene. Under test temperature of 25 ℃, the volatility of the pine oleoresin-based plant oils for 8 h were less than 45.9%, with 2.1% of the least volatility of ND-100, whereas the volatility of xylene was 100%. The solubility of pine oleoresin-based plant oil ND-60 against the technical materials of 47 pesticides showed that 6 pesticides (12.8%), namely emamectin benzoate，fenbutatin-oxide, flusilazole, tebuconazole, lambda-cyhalothrin and azocyclotin, had remarkablely higher solubility than that in the control solvent of xylene, while 15 pesticides (31.9%）, including spinosad and methidathion, were relatively less soluble in comparison with that in xylene. Measurements of the qualities of 42 emulsifiable concentrate preparations indicated that 30 preparations (71.4%)，especially the preparations of deltamethrin, lambda-cyhalothrin and chlorpyrifos, exhibited qualified compatibility and stability in ND-60. These results suggested a positive potential of pine oleoresin-based plant oils as natural alternatives of aromatic solvents in the application of pesticide formulation.

Abstract:Application of protein bait adding high-efficiency and low-toxicity pesticides is an important approach controlling fruit flies in the world. Under laboratory conditions, the contact and stomach toxicity of several pesticides to Bactrocera dorsalis were tested for screening the pesticides of high-efficiency, low toxicity and good proten bait compatibility. The results of contact toxicity showed that spinosad was the best due to its lowest LC₅₀ of 72.33 mg·L^-1. The contact toxicity of other four pesticides in order was avermectins, malathion, ethiprole and chlorfenapyr. The results of stomach toxicity showed that avermectins and spinosad were better than those of other three pesticides, of which the LC₅₀ were 13.99 and 15.76 mg·L^-1 respectively, and 95% confidence interval range were 11.72-16.97 and 13.09-19.23 mg·L^-1 respectively. The effect of other three pesticides in order was chlorfenapyr, ethiprole and malathion. The bioassay results showed that the attractant effect of hydrolyzed protein dropped in various degrees after adding pesticides. The attractant rate of protein bait adding spinosad was 55.83%, only a decrease by 4.17% compared to hydrolyzed protein stock solution, which was the best among the five tested pesticides.

Abstract:The olfactory response of adult Conopomorpha sinensis Bradley to volatiles extracted from different tissues of host plant was evaluated by Y-shaped olfactometer under laboratory conditions. The results showed that the attractive rates of volatile from pulp of litchi and longan to unmated females reached 76% and 68% respectively,while the attractive rates of volatiles from leaves of two hosts were only 32% and 40% respectively. The attractive rates of volatile from pericarp of litchi and longan to the mated females were 72% and 60% respectively. For mated males, the attractive rates of volatiles from host plant tissue were less than 32%. The results indicated that the taxis of C. sinensis to host volatiles varied according to sex, mated status and plant tissues extractive. C. sinensis tended to be attracted to volatiles from the pulp of the host plants before mating,but to volatiles from the pericarp after mating.

Abstract:Pachycondyla astuta Smith, Diacamma rugosum (Le Guillou), Odontoponera transversa (Smith) and Harpegnathos venator (Smith) are common ponerine ants in east China and south China. They are potential natural enemies of forest termites. Twenty nests of the four ponerine ant species were excavated to study their nesting environment, nest architecture and organisms present in their nests. The results showed that the ponerine ants mainly built their underground nests in rubber plantations and litchi forests. Their nests were simple, with only several to dozens of layered or random chambers in the soil. The depth of the nests was usually less than 0.6 m. Organisms including insects of Hymenoptera and Isoptera as well as some small soil animals were found in or near the nests. Their relationships with the ponerine ants are sympatry, symbiosis and prey-predator relationship.

Abstract:OsCER4 gene is a member of fatty aldehyde decarbonylase gene family and is highly homologous to CER1 gene in Arabidopsis, however, it is still not known whether OsCER4 participates in the synthesis of cuticular wax. A 1946-bp genomic fragment located on the upstream of the annotated ATG start codon was amplified and used as cognate promoter for antisense RNA vector construction, and a 624-bp fragment of the OsCER4 cDNA was amplified from total RNAs isolated from Zhonghua 11, and then the cognate promoter and OsCER4 cDNA fragments were cloned into the pCAMBIA1380 which was transformed into rice by Agrobacterium-mediated method. The results showed that the antisense transgene driven by the cognate promoter was constructed and transformed into rice successfully, and most of the OsCER4 antisense RNA transgenic plants were positive and segregated as single T-DNA insertion by PCR and segregation analysis of Hyg-resistant in T₁ progeny, and the expression of OsCER4 significantly decreased in the OsCER4 antisense RNA transgenic plants by Western blotting.

Abstract:A litchi LEAFY homologue (LcLFY) cDNA in full length was isolated from floral buds in ‘Nuomici’ litchi, Litchi chinensis, using RT-PCR and RACE-PCR. The full length of the cDNA was 1 397 bp, containing an open reading frame of 1 171 bp, which encoded 390 amino acids. Furthermore, RT-PCR analysis revealed that LcLFY was expressed during floral differentiation. LcLFY mRNA began to accumulate in buds in the early stage of floral differentiation, and it increased in floral primordium formation stage. However, the LcLFY transcription level decreased in flower formation stage.

Abstract:Half-year-old seedlings of 10 new varieties of Elaeis guineensis Jacg (RYL31-RYL40) were studied under low temperature stress conditions in order to evaluate their physiological and biochemical characteristics. With the increase of intensity of low temperature stress, chlorophyll content showed an increased-decreased-increased change trend; proline and soluble protein showed an increased-decreased trend; soluble sugar contents were closely related to the temperature, increasing with the intensity of low temperature stress; MDA content and relative conductivity of the varieties first decreased and then increased, however, RYL37, RYL38 and RYL39 presented continuous decrease trend. The different physiological indexes exhibited different reactions to the temperature; mild hypothermia could enhance the plant defense function, while high strength (low temperature) could disturb the defense function of the plants.

Abstract:Dunaliella salina, a unicellular green alga with environmental tolerance, was employed as test organism to investigate the toxicity effects of a pesticide dimehypo. The influences of dimehypo on cell growth, single cell β-carotene level, cell morphology changes, and activities of superoxide dismutase (SOD) and catalase (CAT) were investigated. At the mass concentrations less than 0.5 mg·L^-1 dimehypo, cell responses were similar to control. When treated with 1.0-4.0 mg·L^-1 dimehypo, cell growth and single cell β-carotene levels declined at first and then revived. When mass concentrations were higher than 5.0 mg·L^-1 dimehypo, both cell growth and single cell β-carotene levels decreased until they were undetectable. The 10 d IC₅₀ of dimehypo on D. salina was 32 mg·L^-1. Dimehypo could stimulate the increase of CAT activity at a low concentration.

Abstract:Telenomus remus Nixon (Hymenoptera: Scelionidae) is an egg parasitoid of Noctuidae insects.The antennal sensory sensilla of female parasitoid were observed with scanning electron microscopy. Nine distinct types of sense receptors were observed, including sensillum basiconica, sensillum trichodea, sensillum trichodea curvata, sensillum styloconicum, sensillum campaniformium, fluted bent-tipped sensillum, pore-tipped ampullaceous sensillum, sensillum gemmiformium and sensillum chaeticum. Three forms of sensillum basiconica (SB) were found. SBⅠ were distributed at the end parts of scape that link the head and pedicel; SBⅢ were only found at the flagellum, and SBⅡ were always accompanied with the pore-tipped ampullaceous sensillum. Sensillum trichodea were distributed widely on the antenna with larger amount. However, the other seven sensilla were mainly distributed at the eighth to the eleventh fragments of antenna.

Abstract:To investigate the polymorphism of mitochondrial D-loop in water buffalo, the entire mitochondrial D-loop region of 66 water buffaloes of five different groups were analyzed, and 58 mitochondrial haplotypes with 147 polymorphic sites were detected. The haplotypes of swamp buffaloes and river buffaloes formed two different clusters, based on the phylogenetic trees constructed with ML method using bovine D-loop sequences as outgroup. The trees showed that swamp buffaloes and river buffaloes belong to two distinctly different clusters, and two small clusters were observed in the swamp cluster among the three. By median joining network analysis, three different clusters were also founded, one high diverged clusters between swamp and river buffalo, and two little clusters appeared in the whole swamp cluster. The mismatch distribution analysis showed that there might have been two different indepent population expansion events in the evolution history of buffaloes. Pooled with 211 released D-loop sequences of Genbank, and 129 haplotypes with 158 polymorphic sites were detected in 878 bp multi-aligned region. The phylogenetic tree and median joining network analysis also showed that there were three clusters in all sampled buffaloes, two swamp buffalo’s clusters and one high diverged river swamps. Two obviously wave crests appeared in the mismatch distribution analysis, which meaned that there might have been two different population expanding events in water buffaloes. Based on the above results, it could be predicted that river and swamp buffaloes decented from two different domestication events, and there were at least two ancestor gene pools in the domestication of swamp buffaloes.

Abstract:In this research, the growth rules of pectoral of Peking duck coming from the paternal line were analyzed and the mathematical models for the growing pectoral were also estimated. In addition, direct and indirect selection responses on pectorals were further compared. Results indicated that pectoral was late maturing and logistic function was fit for describing the growth rule of the pectoral mass. The length of breastbone could be used as a marker in pectoral selection.

Abstract:Two isolates of Newcastle disease virus (NDV) recently prevailing in Guangdong Province were collected. The whole genome sequences were analyzed. The 3D (three-dimensional) structures of F protein monomer and the C′end of HN protein monomer of GM, JM, LaSota and F48E9 were successfully constructed by homology modeling and MODELER program on SGI Indigo2 IMPACT10000. Comparisons of the whole 3D structure of F protein showed that there were no obvious differences among these strains. The results also revealed that F protein was composed of three main parts, the head region, some β-pleated, sheets and the neck region consisted of a β-pleated sheet and α-helix motif whereas the stalk region mainly consisted of α-helix motif. Comparisons of ASA and fraction of NDV F protein showed that there were five lined B cell epitope peptides and eight conservative antigenic determinants sites. It also showed there was a notable variation in spatial structure of the head region of F protein, with 36 residues difference between GM and F48E9 and 20 residues difference between JM and LaSota. The study also showed that the C′end of HN protein monomer of strains GM, JM, LaSota and F48E9 were identical and mainly consisted of some β-pleated sheet and four α-helix motifs, in which antigenic determinants sites were highly conservative and had only four sites variation among these strains. This indicated that the variation of the NDV antigenic made the development of new vaccines NDV inevitable.

Abstract:According to three active T lymphocyte epitopes (TCE) which Stevenson screened, tce gene (180 bp) was synthesized and cloned successfully into pMD18-T Simple vector. tce gene was subcloned into prokaryotic expression vector pET-32a(+); the recombinant plasmid was named pET-TCE and induced by IPTG. The results of SDS-PAGE and Western-blot indicated that the tce gene was expressed at a high level, and the recombinant fusion protein was about 25 000. The recombinant fusion protein has a peculiar reaction to porcine circovirus 2 (PCV2) positive serum which has immunological activity.

Abstract:Viable but non-culturable Salmonella was detected by RT-PCR with primers designed according to the differential viable but non-culturable (VBNC) genes, ybbB and rh1B. The results showed that primers C1 and C5 respectively amplified fragments about 198 and 137 bp, their nucleotide sequence homology with ybbB and rh1B was both over 99%, and the electrophoretogram form VBNC Salmonella was different from that of normal Salmonella, Vibrio cholerae, et al. The lowest cDNA detection level with primers C1 and C5 in VBNC Salmonella was respectively 30.65 and 3.065 pg/μL. Primers C1 and C5 with specificity and sensibility were applied to establish the detection method in VBNC Salmonella.

Abstract:A method has been developed for the determination of dexynivalenol in edible tissues of swine by liquid chromatography coupled with electrospray ionization tandem mass spectrometry （LC-MS/MS）.The samples were extracted by pure water and purified by C₁₈ solid phase extraction, and then analyzed by the LC-MS/MS after redissolved by 30% methanol. The chromatographic column was Phenomenex Luna 5 μ C₁₈(2), and the flowing phase was comprised with methanol-0.1% formic acid solution (V/V=3∶7). The mass spectrometry was run with electrospray ion source and in positive ions multiple reaction monitoring mode for the quantitative and qualitative analyses. Limit of detection (LOD) was 25 μg·kg^-1, and limit of quantitation (LOQ) was 50 μg·kg^-1. The recoveries of dexynivalenol in edible tissues of swine ranged from 80.2% to 99.4% in 50, 100 and 500 μg·kg^-1 concentration levels. The relative standard deviation ranged from 2.47% to 9.47%.

Abstract:According to the requirements for seeding accuracy of pneumatic roller-type vegetable seeder and feed-rate of seedling tray matching up to rev of seeding device, a controlling system based on C language for the seeder developed by using ATmega16 MCU as core hardware, every cell pan position detection control strategy and modular design of the program approach. The system could solve the impact of the cumulative error on seeding caused by seeding roller line speed and cell pan convey speed difference in continuous work, and it could make the seeder operate in working conditions rapidly and prevent overshooting phenomenon when hard braking was used in high speed working conditions, which insured that seeding device could operate stably in high-speed under the same seeding accuracy conditions. The result indicated that the error between measurement value and theoretical value was up to 2.01% in the operation speed of seeding roller and cell pan convey device under different productivities. The difference between seeding roller line speed and cell pan convey speed was up to 0.1 m/min; it was far less than the theory of permit value 14.4 m/min, which could meet the work requirements of the seeder.

Abstract:A novel Schiff base, 5-(chloromethyl)salicylaldehyde-phenylalanine, and its transition metal (Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺) complexes were synthesized in ethanol. The ligand and complexes were characterized by elemental analysis, molar conductance measurement, IR, UV and TG-DTA, and their antibacterial activities were detected by paper-disc method and the double-dilution-method. The results showed that the Schiff base was the electrolyte of 1∶1 type with the formula of KHL·H₂O（L=C₁₇H₁₄O₃NCl^2-）and these five complexes were the nonelectrolytes with the formula of ［ML(H₂O)］·nH₂O. The nitrogen atom of imino group and the oxygen atoms of phenol group and carboxyl group in the ligand and one water molecule were coordinated with the central metal. The fluorescence experiments showed that the fluorescence intensity of each complex was higher than that of the Schiff base, and the zinc complex had the highest fluorescence intensity. The in vitro antibacterial experiments exhibited that all of the Schiff base and the complexes had antibacterial activities and each complexe had a higher antibacterial activity than that of the Schiff base. The copper complex had the highest antibacterial activity against Escherichia coli and Staphylococcus aureus and its minimal inhibitory concentrations (MIC) against these two bacteria were 25.0 and 12.5 μg·mL^-1 respectively.

Abstract:The aim of this paper is to conduct a bioinformatics analysis for p113 gene of Mycoplasma ovipneumoniae and further predict its functions. Using several softwares, homology of p113 gene with other genes was calculated and trans-membrane structure, repeat sequence, signal peptide and epitodes were predicted. The results revealed that p113 was an orthologous of Mycoplasma hyopneumoniae adhesin gene pp97 which shared similar R2 repeat sequence. Overall analysis leads to the prediction that P113 protein is one of the important adhesins and membrane immunogens.

Abstract:Microstegium somae (Hayata) Ohwi，Themeda yunnanensis S. L. Chen et T. D. Zhuang are reported as new records of Gramineae from Guangdong Province. All the voucher specimens cited in this paper are preserved in the Herbaria of Shenzhen Fairy Lake Botanical Garden(SZG) and South China Agricultural University(CANT).

Abstract:Bromus catharticus Vahl. and Lolium multiflorum Lamk. were reported as newly recorded naturalized plant species from Guangdong Province, China. The voucher specimens are now deposited in the Dendrological Herbarium of Forestry College, South China Agricultural University (CANT).