Abstract:Since the success of transferring a foreign gene into plants and the expression of the incorporated gene in the transgenic plant genome in 1983, plant biotechnology has been developing for 30 years. From researches in the laboratories to practical applications in the farms, the importance of this new technology in the production of food and forage has been proved. In the year of 2012, the areas of biotech crops planted reached 170 million hectares, compared with 1.7 million hectares in 1996, the first year when commercialized transgenic crops were adopted globally. Most of the products on the current market belong to the first generation products, which target to reduce farmers inputs. The development of the second generation transgenic plants focused more on increasing the crop yield, stress tolerance as well as quality improvement. Golden rice and drought tolerant maize are two of the successful examples. The third generation biotechnology of breeding programs, which utilized plants to produce recombinant proteins，such as pharmaceuticals and industrial, have also developed rapidly in recent years. Several such kinds of products are now at different stages of clinical trials. With the speedy progress of life science and technology, this new breeding technology will be continuously improved and a greater role will be expected from it for the development of sustainable agriculture.

Abstract:Oryza sativa and O.brachyantha belong to AA and FF genomes in genus Oryza, respectively. The interspecific hybridization barrier limits the transfer of elite genes from O.brachyantha into O.sativa. By using technique of whole-mount eosin B-staining confocal laser scanning microscopy, the development of hybrid embryo and endosperm after crossing between O.sativa and O.brachyantha and embryo sac abortion process of interspecific hybrid F₁were observed. The results showed that there was a high double-fertilization ratio of 82.93% appearing in the pollinated spikelets, but hybrid embryo ceased to develop and began to degenerate at the globular-shaped stage, meanwhile, free endosperm nuclei degenerated before forming cellular endosperm. It induced hybrid embryo abortion and the matured hybrid seed failed be produced. During the process of hybrid embryo sac development, hybrid megasporocyte finished meioses, but abnormal tetrad was formed which induced abnormal functional megaspores. Embryo sac was degenerated at the stage of mono-nucleate and two-nucleate embryo sac, therefore, no normal embryo sac was formed and hybrid was highly sterile.

Abstract:The variations in traits of space mutated offspring of two maintainer lines of three line hybrid rice, HT-B and Y Huanong B, were studied. The results showed that the SP₁ generation displayed varying degrees of impairment ingerminationrate, bud length, and seeding height, but no evident variation in the other economic traits was found compared with the control. Positive and negative variations in several agricultural traitsemerged in SP₂ and SP₃ generations and an unusually wide range of variations were discovered in amylose content (AC) from extremely low AC（w=1.66%） in waxy mutantand to extremely high AC (w=38.03%) in non-waxy mutant. The pollen sterility and the selfing mature rate of the offspring from test cross between SP₄ mutants and their correspondent male sterile lines were also studied. The maintaining ability for male sterility greatly varies in the space mutants, and completely fertile strains found in the offspring from the test cross are promising resources for novel elite maintainer lines.

Abstract:A joint five generations (P₁, P₂, F₁, F₂ and F_2∶3) derived from a cross of HFA 1 (indica) ×02428 (japonica), two parents exhibited multi-tiller and less tillers respectively, were evaluated to estimate the genetic model and genetic parameters of percentage of productive tiller (PPT) using the mode of major gene and polygene mixed inheritance of quantitative traits. The results showed that the PPT in rice was controlled by the mixed genetic model of one-major-gene plus polygenes (model D-4). The heritability of PPT of major gene in F₂ and F_2∶3 generation varied from 55.51% to 53.57% and those of polygenes varied from 33.13% to 38.94% respectively, which suggested that the breeding for high PPT rice should not only take into consideration both major genes and polygenes, but also carry out the selection for it at the early stage of breeding procedure. The additive effect and the dominant effect of PPT in the joint generations were -19.92 and -6.48 respectively, which implied that the negative interaction effects of polygenes should be considered in high PPT breeding.

Abstract:To clarify the root spatial distribution characteristics of rice, root box experiments were conducted to collect root distribution data. The equation Y = α(1-b^X), where Y is the total root length, and X is the distance of root horizontal distribution or the depth of root vertical distribution, was used to establish root distribution model. Moreover, influences of water management on root growth and distribution were analyzed using the model. The results showed that about 88% of roots were distributed in the top 10 cm soil layer, and 60%-70% of the roots were distributed in horizontal range of 10 cm from the plant at tillering and ripening stages. The change in total root length with the distance of root horizontal distribution or the depth of root vertical distribution could be simulated by the equation Y = α(1-b^X). Water management had impact on rice root vertical distribution and root number without affecting the root horizontal distribution. The rice roots were 0.6 and 3.5 cm deeper, 19.8% and 26.4% longer, and 28.3% and 21.0% greater in number under intermittently flooded irrigation compared with wet irrigation and continuously flooded irrigation, respectively. The variation of average angle of roots showed similar tendency.

Abstract:In order to breed wheat varieties with high yield and high drought resistance, the drought resistance of 196 wheat germplasms was divided into six types, including Triticum turgiduum subsp.turgiduum, T.turgiduum subsp.durum, T.aestivum subsp.aestivum, T.aestivum subsp.compactum, T. aestivum subsp.Yunnanense etc. landraces and the obsolete varieties or lines of T.aestivum subsp.aestivum were evaluated using a natural drought and irrigated condition during the whole growing period in Yunnan Province and the relativity between drought resistance index (I_DR) and main agricultural traits was also analyzed. The results showed that drought resistance of Yunmai42 was higher than those of Yunmai39 and Yunxuan11-12, and it was a standard check variety for excavating materials of the high drought resistance of wheat gerplasm during whole growing period in Yunnan. Fourty-eight wheat germplasms with stronger(I_DR ≥1.1) drought resistance were screened out, which accounted for 24.2% of all the test materials, and the drought resistance of the six tyepes of materials was obvious different, whose order was T.turgiduum subsp.turgidum > T.aestivum subsp.Compactum > T. aestivum subsp.Yunnanense > T.turgiduum subsp.durum > T.aestivum subsp.aestivum > the obsolete varieties or lines. The relativity between I_DR and the number of grain per ear（r =0.525^*）, thousand kernel mass（r =-0.719^**） without irrigated condition and between I_DR and effective spikes per plant（r =-0.399^**）,thousand kernel mass（r =0.342^*）in irrigated condition was significant, which could be used as three supplementary morphological traits of identifying the drought-resistant ability of wheat varieties and materials during whole growing period.

Abstract:Quebrachitol is one of the naturally occurring bioactive inositol stereoisomers, which can be used to synthesize nontoxic chiral medicine for cancer, Alzheimer's disease, diabetes, etc. In the present study, abundant quebrachitol was identified in Sapindaceae fruit crops, Litchi chinensis and Dimocarpus longan using GCMS and HPLC-ESI-MS. High concentrations of quebrachitol were detected in the leaf, bark, pericarp, aril and seed of the species. In litchi cv. Heiye, their concentrations were 7.7, 4.6, 10.8, 1.6 and 9.6 g·kg^-1, respectively. In longan cv. Chuliang, their concentrations were 7.6, 7.3, 5.6, 6.3 and 5.6 g·kg^-1, respectively. Quebrachitol concentrations in the aril of twelve litchi cultivars were surveyed. The possible use of the residue from litchi and longan processing for quebrachitol isolation was also discussed.

Abstract:Effects of different air-curing treatments on aroma constituents of tobacco leaves were studied by using the electric-heated flue-curing barn designed and made by Henan Agriculture University. The results showed that tobacco air-curing 48 h then baking could increase the contents of main neutral aroma constituents such as β-damascenone, gerany lacetone, a giant buan three diluted ketone benzene, methanol, furfural by 37.56%, 13.96%, 60.40%, 22.22%, 90.97% respectively，and the contents of malic acid and citric acid by 15.52% and 55.2% respectively, while the content of linoleic acid, linoleic acid and linoleinc acid could be reduced by 308.51% and 305.04% respectively.

Abstract:In order to evaluate the water quality in Yongjiang River, Ningbo, the spatio-temporal changes of DO, BOD₅, COD_Cr, TN, TP and Chl-a were studied by analyzing water samples from 13 sections within 12 months. Comprehensive evaluation of water quality in different sections was made in fuzzy mathematics methods. The results showed that DO content was negative correlate with contents of BOD₅, COD_Cr, TN and TP. The main water environmental factors, e.g. BOD₅, COD_Cr, TN, TP and Chl-a, were at lower levels in the upper reaches of the river, at higher levels in middle reaches and at lower levels again at the lower reaches. The seasonal changes of main physical and chemical factors displayed unimodal or bimodal patterns in different sections. Fuzzy mathematics comprehensive analysis revealed that the water qualities of the different sections from the superior to the inferior were described in the following order: section 1>section 2>section 13>section 9>section 11>section 12>section 5>section 10>section 8>section 4>section 7>section 6>section 3. Water quality at the most sections, except for section 1, 2 and 9, met level Ⅴ, and the seasonal change was presented as winter>spring>summer>autumn.

Abstract:The quantitative correlations between the soil fertility factors and microbial biomass were studied by the analysis of the soil fertility and microbial biomass contents collected from Huili tobacco growing areas of Sichuan Province. Polyfactorial regression analysis showed that different kinds of soil fertility factors could affect the contents of different kinds of microbial biomass. There were no significant correlation between pH and the content of bacteria in vigorous period, but the other four soil fertility factors were correlated with it. The available nitrogen was positively correlated with the content of bacteria in maturity period. Partial correlation and path analysis suggested that the interaction effects of available phosphorus and pH were positively correlated with the content of fungi in group pieces, also the significant effects of organic matter and pH were discovered. There were obvious interaction effects of available nitrogen and fungi in maturity period. The results also showed that actinomycetes had a correlation with available phosphorus, organic matter and pH in three different periods, and the relationship between soil fertility factors and microbial biomass was different.

Abstract:The bacterium associated with ratoon stunting disease of sugarcane usually gather in the 2-3 internodes of base stem section of sugarcane. The ultrastructures of the stem tissue infected by ratoon stunting disease were observed with electron microscopy. The results suggested that cytopathological alteration apparently occurred inside cells and on the cell wall. A large amount of electron-dense substances accumulated in the infected cells, which was presumed to be associated resisting, reducing or delaying the invasion of this disease. The electron-densed substances were only found in the infected cells. The cell wall was thickened and there was a layer of adhesive materials in the vessels of vascular bundle. Some cell walls were uneven with different thickness, and parts of them were broken into crumbs and fiber silks.

Abstract:This paper reports a plate assay to detect activities of polygalacturonase and cellulase secreted by Fusarium oxysporum f. sp. cubense (FOC), which is the most destructive pathogen of banana. The optimum cultural conditions for the polygalacturonase production were using pectin as induced substrate to inoculate with 1×10 ₄ mL^-1 conidia of FOC and after being cultured for 3 days. The optimal temperature of polygalacturonase activity was 37 ℃. The optimum cultural conditions for cellulase production were using carboxymethyl cellulose (CMC) as induced substrate to inoculate with 1×10 ₅ mL^-1 conidia of FOC in inducing medium after being cultured for 3 days. The optimal temperature of cellulase activity was 37 ℃. Based on the method, two mutants with impaired polygalacturonase and cellulose activity were attained through screening virulence-reduced mutants of FOC.

Abstract:In order to conserve and utilize natural enemies for comprehensive control of pests in tea garden, the seasonal variations of population quantities of two pests and their natural enemies in “Ping yang te zao” tea garden were investigated systematically. The results of a paired t-testing showed that the t-values of eight natural enemy numbers, i.e. Leis axyridis (Pallas); Misumenops tricuspidatus (Fabr.); Tetragnatha squamata (Karsch); Clubiona japonicola (Boes.et Str.); Erigonidium graminicolum (Sundevall); Oxyopes sertatus (L.Koch); Propylea japonica (Thunberg); Theridion octomaculatum (Boes.et Str.), were respectively 0.78, 1.65, 0.81, 0.16, 2.09, 1.72, 1.38 and 0.79, between the seasons of spring-summer and autumn-winter in 2010, which all were significantly lower than 2.13 (t_0.05 value), indicating that there was no significant difference between numbers of two insects and their natural enemies during the two seasons of spring-summer and autumn-winter in “Ping yang te zao” tea garden. The quantity, time and space framework of Aleurocantus spiniferus (Quaintance) and Demotina fasciculata (Baly) and their predatory natural enemies in 2010 spring-summer season and autumn-winter season were systematically studied using grey system analysis, ecological niche analysis and aggregated-intensity index analysis of spatial patterns. The synthetic ranking results indicated that in 2010 spring-summer season, the orders of main natural enemies of Aleurocantus spiniferus (Quaintance) and Demotina fasciculata (Baly) were respectively Tetragnatha squamata (Karsch), Misumenops tricuspidatus (Fabr.) and Theridion octomaculatum (Boes.et Str.), Propylea japonica (Thunberg), Leis axyridis (Pallas) and Erigonidium graminicolum (Sundevall). In 2010 autumn-winter season, the orders of main natural enemies of the two pests were respectively Tetragnatha squamata (Karsch), Misumenops tricuspidatus (Fabr.) and Clubiona japonicola (Boes.et Str.); Leis axyridis(Pallas),Misumenops tricuspidatus (Fabr.) and Propylea japonica (Thunberg). In addition, the results also showed that the λ value of gathering average of Aleurocantus spiniferus(Quaintance) was over 2 in April 24, 2010, indicating that the aggregation of pest was caused by itself. However, the λ values of gathering average of all enemies were smaller than 2, implying that the aggregation of most natural enemies was caused by different environmental factors.

Abstract:The field experiments and systematic investigation were made to study the effects of intercropping of cabbage and garlic on major pests and arthropod community in spring cabbage fields. The results showed that the intercropping of cabbage and garlic was able to reduce the degree of occurrence of major pests, Pieris rapae and Lipaphis erqsimi, raise the diversity and the ratio of natural enemies to pests of arthropod community, and was helpful to improve the community stability and reinforce the control of natural enemies on pests in spring cabbage fields. The average population density of major pests, Pieris rapae and Lipaphis erqsimi was reduced by 48.9% and 35.6% respectively, and the average diversity index and the ratio of natural enemies to pests of arthropod community rised by 17.9% and 61.8% respectively in intercropping field of 1 line cabbage and 1 line garlic as compared with those in cabbage monoculture field. Therefore, the intercropping of cabbage and garlic was helpful to reduce the pressure of cabbage pests caused by other control methods, including using insecticides, and improve the effects of provention and treatment and comprehensive benefit.

Abstract:The sugarcane variety GT28 was employed as materials in this experiment. The young seedlings were sprayed with abscisic acid (ABA) and its biosynthesis inhibitor, sodium tungstate, before 12 h of cold treatment. Leaf +1 and tender root samples were taken at different stages of cold treatment. Malondialdehyde (MDA) contents, active oxygen species (ROS) levels and the activities of antioxidant enzymes were determined during cold stress. The results showed that the activities of antioxidant enzymes increased under cold stress. After ABA application, the content of ABA and the activities of superoxide dismutase (SOD), ascorbic peroxidase (APX), catalase (CAT), peroxidase (POD) and glutathione reductase (GR) increased, while the contents of superoxide anion (O₂^-·), H₂O₂ and MDA decreased in sugarcane seedlings. But when treated by sodium tungstate application, the results were quite the contrary. It can be concluded that ABA and its biosynthesis inhibitor have an important regulatory role in the antioxidant protection system in sugarcane seedlings under cold stress. The cold resistance in sugarcane enhanced by ABA application under cold stress may be associated with the induction of antioxidant protection system.

Abstract:In order to investigate the relationship between root activity and photosynthetic ability at different growth stages of Panax ginseng,the stem of P.ginseng was cut at the base and the root bleeding sap was collected.The root bleeding sap mass(m_BS), as an index indicating root activity,net photosynthetic rate (Pn) and the plant aerial organs absorbing water mass（AWM）of P.ginseng were measured at different growth stages.The results showed that m_BS was lower at flowering stage,higher at green fruit and early red fruit stages and the lowest at red fruit stage.The photosynthesis of leaf was lower at flowering stage,higher at green fruit stage and early red fruit stage and the lowest at red fruit stage.BSW was positively correlated with Pn,PC and AWM.In addition,Pn/m_BS and AWM/m_BS was the highest at red fruit stage.The root activity was closely related to leaf photosynthesis of P.ginseng at different growth stages.

Abstract:To explore the regulatory effect of exogenous hormone on accumulation of the antitumor substance glucosinolate, plants of Shanghaiqing pakchoi (Brassica campestris L. ssp. chinensis (L.) Makino var. communis Tsen et Lee cv. Shanghaiqing) were treated by abscisic acid (ABA) with different concentrations (0, 5, 10 and 20 mg·L^-1) . The results showed that sprays of ABA solutions did not significantly affect biomass of pakchoi. 10 mg·L^-1 ABA treatment significantly decreased the content of aliphatic glucosinolates in pakchoi shoots. However, treatments of 5 and 10 mg·L^-1 ABA significantly increased the contents of indole glucosinolates and neoglucobrassicin. The content of aromatic glucosinolate significantly increased by ABA at 20 mg·L^-1. But 10 and 20 mg·L^-1ABA inhibited the increase in total glucosinolate content. In addition, 10 mg·L^-1 ABA treatment decreased the portion of aliphatic glucosinolates in packoi shoots, increasing the relative percentages of indole glucosinolates and aromatic glucosinolate. It could be concluded that exogenous ABA with different concentrations have different effects on the contents andcomposition of glucosinolates.

Abstract:By using the sensitive (‘472113’) and resistant (‘0417’) inbreed lines to bitter gourd fusarium wilt as materials, the physiological and biochemical changes of Momordica charantia seedling were studied after inoculation with pathogen. The results indicated that activities of polyphenoloxidase （PPO）, phenylalanine ammonialyase（PAL）, catalase (CAT), chitinase (CHT), β-1, 3-glucanase (GUN), peroxidase (POD) and superoxide dismutase (SOD) had a positive correlation with disease resistance. However, malonaldehyde (MDA) content had a negative correlation with disease resistance. In conclusion, the peak value of PPO, PAL, CAT, CHT, GUN, POD, SOD activities and MDA content could be taken as the indicator for bitter gourd fusarium wilt resistance, and PPO activity was the best followed by CHI, GUN activity and MDA content, due to their much closer correlation with bitter gourd Fusarium wilt resistance.

Abstract:Dendrobium nobile was transformed by ovary-injection of Agrobacterium. After artificial pollination in 10, 20, 30, 40, 45, 50 and 60 d, EHA105(pCAMBIA1301) harboring both β-glucuronidase gene (GUS) and hpt was injected into the ovary. The seeds of split fruit of D. nobile were cultured on the N16 culture medium by aseptic processing and detected by GUS expression. Forty-five days after cultured, the protocorms were diverted to N16 medium with hygromycin to gain hygromycin-resistance protocorms, then four randomly selected hygromycin-resistance protocorms were detected by PCR analysis. The study showed that ovary-injection of agrobacterium had harmful effects on the fruit development and seed formation. Ovary-injection of agrobacterium after artificial pollination 45 d had the highest efficiency, 18% seeds from the injected position showing GUS expression. Eleven hygromycin-resistant plants were gained in this study, and four randomly selected hygromycin-resistant plants were detected by PCR analysis and all of them were positive. The results showed that ovary-injection of agrobacterium transformation had advantages in genetic transformation of orchids.

Abstract:The study of stand spatial structure is a significant precondition for modern forest management. In 2005, a permanent secondary popular-birch forest plot of 5.2 hm² was established in Changbai Mountain, in which all trees were measured by diameter at breast height (DBH) and mapped. Its stand spatial structure was studied by means of three indicators, i.e., mingling, neighborhood comparison and neighborhood pattern. The mean mingling and neighborhood pattern of this plot were 0.63, indicating that the forest was above moderate mingling level, and the mingling level of canopy species was higher than that of understory species. The values of neighborhood comparison were from 0 to 0.67, which suggested that all trees were greatly differentiated vertically and the pioneer species of secondary succession were dominant in growth. The value of neighborhood pattern was 0.55, which showed that this forest was aggregated. These characteristics of spatial structure were related to less disturbance, secondary early stage of succession, tree species status in the stand, regeneration mode and reproduction strategy.

Abstract:In this study, the mRNA expression levels of imprinted gene IGF2 and H19 in Landrace and Lantang swine were investigated through real-time fluorescence quantitative PCR. The pigs were grouped according to growth traits. The relationships between mRNA expression levels with growth and reproductive traits were analyzed. The results showed the IGF2 mRNA expression levels of liver in the heavy birth body mass group was higher than that of the light birth body mass group. When 180 days old, the IGF2mRNA expression levels of fat in the thick sebum group was higher than that of the thin sebum group. The IGF2 mRNA expression levels of liver, muscle and stomach in 1 day old piglet were higher than those in other tissues. The H19 mRNA expression levels of kidney in 180 days old Landrace pig increased significantly.

Abstract:In the present study, green fluorescent protein(GFP) transgenic embryos were reconstructed by nuclear transfer of GFP positive cells into enucleated in vitro matured oocytes. The development of reconstructed embryos both in vitro was observed, and GFP expression was checked as well. This research was conducted to study the processing of nuclear cells, the method of nuclear transfer and fusion/activation on early development in vitro of reconstructed embryos. The results showed that there were no significant differences in the cleavage rates between serum hunger and not hunger training 10 d using injection ways of perirenal space of eggs, and the cleavage rate of reconstructed embryos with intracytoplasmic injection (81.11%) was not significantly higher than that of the perirenal space of eggs (76.80%). After activation treatment, the rate of cleavage were assessed on 2 days, respectively. Although there were no significant differences in the cleavage rates of the first two treatment groups (75.61% and 83.07%), the developmental rate was significantly higher than that of the third group(60.00%).

Abstract:The study investigated the effects of different microbial lipases on growth performance, serum biochemical indices, and pectoral muscle nutrients of yellow-feathered broilers. A total of 400 1-d-old male yellow-feathered broilers were randomly divided into 4 treatments with 4 replicates for each treatment and 25 chickens in each replicate. Treatments were consisted of control group, lipase group A, lipase group B, and combinatorial enzyme group. The lipases were added as 35 000 U for 1 kg lard. Lipase addition promoted development of male yellow-feathered broilers, increased average daily feed intake and average daily gain, and decreased feed to gain ratio in the whole and the late period of experiment (P<0.05).Lipase supplement reduced the total cholesterol, high density lipoprotein (HDL), and low density lipoprotein (LDL) content in the male yellow-feathered broilers’ serum at the late-period experiment (P<0.05), increasing HDL,LDL ratio. Different lipases had different influences on protein and fat content of breast muscle dry matter of male yellow-feathered broilers. The results indicated that lipase addition could improve male yellow-feathered broilers’ growth performance, lipid metabolism, and impact their pectoral muscle nutrition deposition, which may be relative to lipase hydrolysis specificity.

Abstract:The present experiment was conducted for 60 days to investigate the suitability of cyclical feeding with two dietaries on the growth performance, feed utilization, body composition and serum biochemical indexes of hybrid tilapia (Oreochromis niloticus♀×O.aureus♂) with the initial body mass of (3.10±0.05) g. Seven different feeding regimes employed were: 27.49% protein diet (hereafter referred to as a) continuously (group A), 20.55% protein diet (hereafter referred to as b) continuously (group B), one day a followed by one day b ( group 1A/1B), 2 day a followed by 2 day b (group 2A/2B), 2 days of a followed by 3 days of b (group 2A/3B), 3 days of a followed by 2 days of b (group 3A/2B) and 3 days of a followed by 3 days of b (group 3A/3B). Each feeding regime fed three replications. The results were as follows: group B had the worst growth performance. Compared to specific growth rates of 1A/1B, 2A/3B and 3A/2B were not significantly different from group A (P>0.05), but their protein efficiency ratios and protein retention rates were remarkably higher (P<0.05), and feeding costs were significantly lower (P<0.05). Viscerosomatic indexes of group A, group 3A/2B and group 3A/3B were significantly lower than those of the other groups (P<0.05). Survival rate of group 1A/1B was not significantly different from that of group A (P>0.05), but it was obviously lower than that of the other groups (P<0.05). Whole body moisture contents of group A, group 1A/1B, group 2A/3B and group 3A/2B were obviously lower than those of group B (P<0.05). Crude fat content of group A was obviously lower than that of the other groups (P<0.05). All the groups except group B had no significantly different crude protein contents compared with group A. Mixed feeding schedules had a significant influence on serum biochemical indices (P<0.05): compared with group A, the activities of aspartate amino-transferase and glutamic-pyruvic transaminase in the serum decreased, the levels of albumin, globulin and total protein rose, and the contents of total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol increased. This experiment indicated that group 3A/2 B was the best feeding regime.

Abstract:A microwave digestion, hydride generation-atomic fluorescence spectrometer method for determining the total mercury residues of mercurous chloride, mercurous nitrate and mercuric acetate in animal derived food was established. The samples were pretreated with microwave digestion and determination by hydride generation-atomic fluorescence spectrometer, with the potassium borohydride as the reductant, and the hydrochloric acid as current-carrying. The density of mercury and its response value was in good linearity over the range of 0.05-2.00 μg/L(r>0.9990). As for mercurous chloride, mercurous nitrate and mercuric acetate, the limit of detection was 0.004, 0.001 and 0.006 μg/L respectively, the limit of quantification was 0.010,0.003 and 0.020 μg/L respectively, the minimum detectable concentration was 1.00, 0.25 and 1.50 μg/kg respectively, the relative standard deviation (RSD) was 3.82%, 3.27% and 4.11% respectively. The average recovery was 89.07%-110.08%, 80.17%-113.10% and 89.83%-112.77% respectively.

Abstract:Ten healthy chickens were selected for the observation of chicken thymus by microcirculation microscope in vivo. Transparent vascular specimens and tissue sections were prepared to observe the overall trend of micro vascular and the fine structure of vascular. The results showed that the blood serving thymus was mainly from vagus artery starting from the small dried branch of common carotid artery and extending to the visceral of the neck and the being skin in middle of neck, then branching into the thymus along the way. The branch divergenced into the vascular tree in the central portion close to the glands, forming capillary network after essence. These capillaries went vertically toward the thymus surface, or they would join the superficial capillaries plexus, or with the capillary bundle a distance to return medulla, they formed the capillary loops. Metarterole was connecting extensive venous plexus composed of irregular meshes, whereas the post capillary venule joined the venues at the cortico-medullary boundary and finally into blood vessels at the surface of the glands, thus forming the thymus vein, which emptied into the external jugular vein.

Abstract:Staphylococcus aureus was induced into viable but non-culturable (VBNC) state by low temperature and potassium sorbate. The resuscitation of VBNC strain was successful when being incubated in brain heart infusion (BHI) medium. The physiological metabolisms and responses to stresses of the resuscitative cells were also studied. The results showed that the morphology and the physiological characteristics of the resuscitative strains were the same as the standard strain except for the negative urease. On blood agar plate, the colonies of the resuscitative strains were white, without hemolysis. Furthermore, the resuscitative strains were more susceptible to stress. This may be related to the lack of ability of carotenoid biosynthesis.

Abstract:The purpose of this research was to explore the effects of different proportions of corn, bran and waste lees on the flavor formation of fermented grains of soybean-flavor liquor. Based on the single-factor test, different flavoring fermented grains formulations were prepared using D-optimal mixture design, with corn of 4%-20%, bran of 30%-50% and waste lees of 40%-60%, which were evaluated by total ester. The results were analyzed by software Design-expert and an optimum formulation was attained by corn mass fraction of 7.22%, bran 33.62% and waste lees 59.16%. The total ester value was 3.86 g/L which was consistent with the predictive value.

Abstract:To achieve effective operation of litchi mechanized bloom thinning, a novel flexible thinning mechanism was developed. By implementing the experimental studies on different treatment methods, it was concluded that the speed and spacing of plastic string both had a significant influence on the thinning time and the rate of thinning flower. No significant differences were found in terms of the fruit-set quantity, fruit mass and fruit size. The thinning time was inversely and positive proportional to the rotational speed of plastic string and space separately, while the flower thinning rate was positive and inversely proportional to the rotational speed of plastic string and space separately. With different mechanical thinning treatments, the fruit mass and fruit size significantly increased along with fruit size and fruit shape index were relatively consistent compared to the control, which the fruit size difference was large. The mean fruit mass and fruit set quantity per cluster had a negative correlation.

Abstract:Carbon stock and the distribution of an 8-year-old Acacia cincinnata plantation in Nanning, Guangxi, China, were investigated based on field sampling data. The results showed that carbon content in different organs of A. cincinnata ranged from 465.8 to 508.2 g·kg^-1, and it was distributed in a descending order as follows: stem＞leaf＞branch＞root＞bark. Carbon content in the soil (0-80 cm) was 8.44 g·kg^-1 which declined with soil depth. The carbon stock in A. cincinnata plantation ecosystems was 126.07 t·hm^-2, which distributed among the tree layer with a stock of 28.76 t·hm^-2, shrub layer 5.35 t·hm^-2, herbaceous layer 1.25 t·hm^-2, litters 1.69 t·hm^-2, and the soil layer (0-80 cm) 89.02 t·hm^-2. Annual net productivity of A. cincinnata plantation was 10.15 t·hm^-2·a^-1, and annual carbon storage was up to 5.64 t·hm^-2·a^-1.

Abstract:The 16S rRNA genes amplification effects of the four simple total DNA extraction methods (freeze-thaw, boiling, alkaline lysis, and ROSE) were compared by extracting DNA from the Gram-negative and gram-positive bacterial strains of 14 genera. The results showed that the extraction effects of the methods from superior to inferior were in the following order: freeze-thaw, boiling, alkaline lysis and ROSE. The freeze-thaw method had advantages of cost-effective, time-and labor-saving and non-pollution. However, it was not always effective for minority gram-positive bacteria. When the DNA extraction of a large number of bacterial strains was required, the freeze-thaw method to extract total DNA of most bacteria may be first used. For the minority of DNA extraction samples which failed, it was advisable to discard the suspension from the freeze-thaw method, then use the chemical methods such as CTAB, SDS or DNA extraction kit for supplement. The freeze-thaw method to extract total DNA could not only save time and reduce cost, but also decrease the production of organic waste during DNA extrction.

Abstract:Three invasive plant species, collected from Fangchenggang city were reported as new records to Guangxi Zhuang Autonomous Region, China, i.e.Euphorbia hyssopifolia L.,Pluchea sagittalis (Lam.) Cabrera and Paspalum urvillei Steud.. All the voucher specimens are now deposited in the Herbarium of South China Agricultural University(CANT), which is located at the Forestry college Building.