The brown planthopper (BPH), Nilaparvata lugens Stl (Hemiptera: Delphacidae), is an important pest of rice in Asia. It sucks rice phloem sap, transmits rice viruses, and often causes serious loss of rice yield. Changes in modern cropping system like the increase in susceptible hybrid varieties, fertilizers, pesticides, and temperature resulted in high frequency of N. lugens outbreaks, mainly attributed to its capability of environmental adaptation. Esterases catalyze the hydrolysis of endogenous and foreign compounds containing ester bond, and play major roles in xenobiotic detoxification, pheromone degradation, neurogenesis, and regulation of development and reproduction in insects. However, the function and mechanism of N. lugens esterases in rapid adaption to environmental factors remains unclear. In this paper, the effects of environmental factors including rice variety, nitrogen application level, and temperature on the activity response of nonspecific esterase in female adults from different populations were preliminarily studied. Three N. lugens populations, collected from Zhejiang and Guangxi of China and Phitsanulok of Thailand, were respectively treated with rice varieties including TN1 (a insectsusceptible indica variety), IR64 (a local indica variety in tropical areas), Xiushui 11 (a local japonica variety in China) and Liangyou 363 (a local hybrid variety in China), nitrogen applications with low and high doses, and temperatures of 21 ℃ and 29 ℃. The nonspecific esterase activity in N. lugens populations was determined spectrophotometrically following the hydrolysis of pnitrophenyl acetate (pNPA) at 405 nm. The results showed that there were highly significant effects of rice varieties, nitrogen application levels, and temperatures on the esterase activity in N. lugens populations, respectively. The esterase activities in N. lugens populations were significantly different, whereas the activity of Guangxi population was about 2.24 times and 1.24 times higher than that in Zhejiang and Phitsanulok populations, respectively. In contrast to significant increase in esterase activities of Zhejiang and Phitsanulok populations after transferred feeding on different varieties, the esterase activity in Guangxi population was mainly inhibited though it increased markedly after transferred feeding on TN1. It was indicated that the changes of esterase activity of N. lugens in response to host shifting might be related to indica and japonicatypes of rice. The esterase activity was significantly induced in Zhejiang and Phitsanulok populations after transferred feeding on the rice treated with lowdose nitrogen, but fluctuated markedly in Guangxi population. Feeding on the rice treated with highdose nitrogen resulted in an increased esterase activity in Phitsanulok population while fluctuated in Zhejiang and Guangxi populations. The esterase activities in N. lugens populations on the rice treated with highdose nitrogen were lower than those on the rice treated with lowdose nitrogen. The temperature changes led to the significant decrease of the esterase activity in Zhejiang and Guangxi populations, but led to the marked increase in Phitsanulok population. The esterase activities in N. lugens populations at 21 ℃ were lower than those at 29 ℃. It is concluded that the response of esterase activity in N. lugens to different environmental factors is populationspecific. Compared with Guangxi population, Zhejiang population has a higher similarity with Phitsanulok population. It is suggested that the esterase and its genes can be used as a candidate character for evaluation of regulatory function of the paddy ecosystem on rice planthopper outbreak.

Rainbow trout belongs to Salmonidae aerobic fish, and it is necessary for high dissolved oxygen content of living water environment. If the dissolved oxygen content of living water is less than 5 mg/L, it will cause the increase of respiratory rate, which is the socalled “aquaculture floating head” phenomenon. Because the fish lives in hypoxia environment and the 90% oxygen consumption is in the mitochondria, the transmission mechanism in composition and electronic respiratory chain may be different from the terrestrial animal. At the mitochondrial inner membrane, electrons from NADH and succinate pass through the electron transport chain to oxygen, which is reduced to water. Complex I is one of the main sites at which premature electron leakage to oxygen occurs, thus being one of the main sites of production of harmful superoxide. The first isolation of mitochondrial complex I since 1961, its composition and structure have had a primary understanding, but the specific mechanism of its participation in respiration, especially the function of each subunit is not clear. The protein encoded by Ndufb2 gene is a subunit of the multisubunit NADH: ubiquinone oxidoreductase (complex I). Mammalian complex I is composed of 45 different subunits. This protein has NADH dehydrogenase activity and oxidoreductase activity. It plays an important role in transferring electrons from NADH to the respiratory chain. Reverse transcription PCR (RTPCR) and rapid amplification of cDNA ends (RACE) methods were used for the isolation of the whole cDNA of Ndufb2 gene from brain of Oncorhynchus mykiss. The assembly taskes of 3′ and 5′RACE sequence were completed by DNAman program. A pair of gene specific primers were designed to amplify the fulllength cDNA sequence. ClustalX 1.81 and MEGA 3.0 software were used to calculate the amino acid sequence differences, and then the phylogenetic relationships of rainbow trout Ndufb2 gene sequence with other species were analyzed. Protein phosphorylation sites and protein kinase phosphorylation sites were predicted using online software NetPhosK 1 and NetPhos 2. Sequence analysis results showed that the rainbow trout Ndufb2 cDNA was 899 bp in length, 5′ untranslated region (5′ UTR) 152 bp, 3′ untranslated region (3′ UTR) 441 bp, open reading frame (ORF) 306 bp, encoding 101 amino acids. The protein molecular mass was 11.4 ku and isoelectric point was 5.31. This gene sequence had been submitted to the GenBank database (accession number: FJ534641). Mitochondrial target sequence of 50 amino acid motif appeared from the 1st to 50th amino acid site. Two antigenic sites (65ILWHCWHDPD74 and 23QKIVIRK29) of the Ndufb2 protein were found, and one serine phosphorylation site (aa49), two threonine phosphorylation sites (aa15, aa47) and seven kinase phosphorylation sites were also found. Sequence alignment exhibited 98% identity of amino acids between O. mykiss and Salmo salar, and more than 55% identity of amino acids between O. mykiss and mammal. Phylogenetic tree showed that the Ndufb2 of rainbow trout had the closest relationship with those of Atlantic salmon and zebrafish, then the amphibians, birds, marsupials and mammals. The phylogenetic analysis showed that the constructed Ndufb2 protein phylogenetic tree was consistent with the traditional species classification tree. The above results indicate that the Ndufb2 gene is relatively conservative in the progress of evolution and play an important role in electron transport process of mitochondrial respiratory chain. The cloned fulllength cDNA sequence of mitochondrial respiratory chain gene Ndufb2 of rainbow trout lays a theoretical foundation for the structure and function of clarifying fish mitochondrial complex I.

Summary Carboxylesterase BioH of Escherichia coli is an important enzyme in the biotin synthesis. It contains a typical catalytic triad of SerHisAsp and displays significant carboxylesterase activities. The enzyme shows a broad substrate specificity with a preference for short acyl chain substrates. This property makes it a biocatalyst with a good application prospect. However, research on the use of this enzyme has been quite few to date. It shows great significance to get the protein and optimize its functions. In this study, BioH gene from E. coli K12 was cloned into pET30a(+) using double digestion method by BamHI and HindIII and was overexpressed in E. coli BL21(DE3) induced by isopropylβDthiogalactoside (IPTG). BioH protein content was calculated by image processing software Quantity One. Its hydrolysis activity was determined by the rate of hydrolyzing pnitrophenyl butyrate (pNPB). And its thermostability was detected after the enzyme was incubated at 60 ℃ for 40 min. In order to improve its hydrolysis activity, a directed evolution method was carried out. pNPB was used as the screening substrate. The product, pnitrophenol, showed the biggest absorption value at 405 nm. The mutant library was built by errorprone PCR method with adjusted Mn2+ concentration. The complete length of the BioH gene was 771 bp and the molecular mass of the protein with 256 amino acids was about 28.2 ku. The targeted enzyme accounted for one quarter of the total expressed proteins. The enzyme’s hydrolysis activity was shown as 18 U/mg and it retained 70% of its hydrolysis activity after incubated at 60 ℃ for 40 min. The thermostability of the enzyme was the foundation in the enzyme application. The optimized concentration of Mn2+ in errorprone PCR was chosen as 0.1 mmol/L determined by agarose electrophoresis of the brightness of PCR product band. And mutant library with a mortality rate of 20% to 40% was appropriate for selection. Sequence detection showed that the mutation rate was kept as 23 changed bases in each gene on average. In each round of directed evolution, a library with 5 0006 000 mutants was screened. In the first round, wildtype BioH was used as the parent and three mutants with improved hydrolysis activity were selected. These mutants were K213E, Q70L/M170T and V175A, and their hydrolysis activities were improved by 10%, 30% and 50% respectively. Subsequently, the two mutants with only one mutation site for each, K213E and V175A, were used as parents to undergo the next round of directed evolution. Three mutants from K213E were selected, namely K213E/M197L, K213E/L180M and K213E/C31Y/F50S, whose hydrolysis activities were improved by 40%, 50% and 95% respectively. In the mutant library of V175A, one mutant, V175A/Q129R, was selected, which showed 100% improvement in hydrolysis activity compared to the wild type. Structure analysis by molecular 3D structure software PyMOL gave a clear view of the mutation sites. Sites 31, 129, 175, 180 were located in the αhelixes and sites 50, 70, 170, 197, 213 were located in the loops of protein structure. All of them were far away from the activity sites. This study clones and overexpresses successfully the carboxylesterase BioH in BL21(DH3). Seven mutants were selected by directed evolution in pNPB method. The enzyme shows a good evolvability. The positive library can be used in further application of this enzyme.

In recent decades, harmful algal blooms (HABs), which are natural phenomena that occur across all the world, have posed threats to decrease dissolved oxygen and have had a negative effect on fisheries, aquaculture, drinking water, tourism and human health. It is increasingly urgent to develop useful strategies for predicting and reducing the negative impacts of HABs. Actually, many methods have been devoted to controlling HABs, including copper sulfate, hydrogen peroxide, ozonization, ultrasonication, collection of algae from water surface using nets, iron powder and magnets, centrifugal separation, or ultraviolet radiation. As an effective and environment friendly strategy to control harmful algal bloom outbreaks, biologic control methods such as using algicidal bacteria against M. aeruginosa have been more and more attractive. It has been demonstrated that algicidal bacteria could serve as potential ways in reducing the impacts of HABs. In this study, a Citrobacter sp. N10 with algicidal activity against the toxic algae M. aeruginosa was isolated and identified from a lake of Zhejiang University using liquid infection technology and 16S rDNA sequence analysis. The growth and algicidal characters of Citrobacter sp. N10 were then studied in order to offer some useful information for HABs controlling. The results showed that the bacterium was gramnegative and its colonies were smooth, convex, low moisture, translucent or opaque and gray, and its colony surfaces were glossy. Sequence analysis of 16S rDNA demonstrated that strain N10 belonged to Citrobacter sp. When inoculation time was 2 to 12 h, N10 grew in logarithmicgrowth period, and when inoculation time was beyond 12 h, N10 was in stationary phase. Strain N10 showed a high lysis of M. aeruginosa with an algicidal rate of 86.55% within 24 h. The algicidal rate of N10 increased with increasing incubation time and reached 97.08% within 72 h. pH value had the most significant effect on the growth of strain N10, followed by NaCl concentration and culture temperature, while these three conditions had different effects on algicidal activities of strain N10 against M. aeruginosa. A kind of substance against M. aeruginosa was secreted by strain N10, and the substance was sensitive to high temperature (121 ℃) but resistant to protease K. Relatively speaking, the thalli of strain N10 had hardly algicidal effect against M. aeruginosa. Transmission electron microscope was subsequently used to investigate algal cells’ structures after 3 d with treatment of strain N10 cellfree culture filtrate (CCF). The results indicated that the cell membranes and cell walls of M. aeruginosa were broken, while the gas vesicles and some particulate matters such as the cytoplasm phosphate particles and blue bodies disappeared. In addition, the cellular ultrastructure of the photosynthetic lamellae was also found to be disordered and disappeared. In conclusion, the research on the characteristics of N10 against M. aeruginosa can provide a tool in controlling the bloom of M. aeruginosa. The findings are of theoretical significance and potential in reducing the impacts of HABs.

In recent years, new alien plants have constantly been invading China as a result of an increase of foreign exchanges. Peperomia pellucida (L.) Kunth, a species that originated from tropical America, is one of the alien species recently found in Shanghai. Its potential geographical distribution range and habitats of the species are still unknown. Scientists have applied a variety of ecological niche models to predict the risk of exotic plant invasions in China. Among these ecological niche models, maximum entropy (MaxEnt) model has higher accuracy of predicted results with small sample size. According to 12 environmental variables from the global climate environment database (http://www. worldclim.org/) and 649 occurrence records of P. pellucida in the world from the global biodiversity database (http://data.gbif.org/welcome.htm) and the Chinese Virtual Herbarium (http://www.cvh.org.cn/cms/), a prediction of P. pellucida potential distribution was conducted using MaxEnt model and ArcGis 9.3 software. In this prediction, 12 environmental variables were used, including precipitation of wettest month, mean diurnal temperature range, isothermality, precipitation of warmest quarter, mean temperature of coldest quarter, variance in precipitation seasonality, precipitation of coldest quarter, temperature annual range, altitude, precipitation of driest month, mean temperature of warmest quarter, and mean temperature of driest quarter. When modeling, the occurrence data and environmental variables were firstly imported into the MaxEnt, and 75% of the occurrence data to predict the risk (training data) and the other (testing data) to test the accuracy were used. The raster layer of P. pellucida was gotten in the global potential distribution in ASCII format, then was imported into ArcGis for further analyses, and the potential suitable areas of P. pellucida in China was gotten. Finally, the result was confirmed by the ROC (receiver operating characteristics) curve analytical method, and the AUC (area under the ROC curve) of the training data and testing data was as high as 0.956 and 0.963, respectively. The predicted result showed that precipitation of the wettest month, isothermality, mean temperature of coldest quarter, precipitation of coldest quarter, altitude were the main environmental variables that affected the invasion risk of P. pellucida. The distribution probability of P. pellucida increased with the increase of precipitation of wettest month, isothermality and mean temperature of coldest quarter. The low altitude regions in China were of higher risk for P. pellucida to invade. Meanwhile, a calculation method to evaluate comprehensively the invasion risk was put forward. According to the invasion grades for P. pellucida in 34 provinces, municipalities, and metropolis (directly under the jurisdiction of the central government) in China, the country is divided into four regions including high risk area (Taiwan, HongKong, Macao, Guangdong, Guangxi and Hainan), moderate risk area (Shanghai, Fujian and Yunnan), low risk area (Zhejiang, Hubei, Jiangsu, Anhui, Jiangxi, Tibet, Hu’nan, Sichuan and Guizhou) and nonsuitable area (Inner Mongolia, Beijing, Heilongjiang, Jilin, Tianjin, Ningxia, Shandong, Shanxi, Xinjiang, Hebei, He’nan, Gansu, Liaoning, Chongqing, Shaanxi and Qinghai). In a conclusion, P. pellucida has a wide range of potential distribution regions including Taiwan, HongKong, Guangdong, Guangxi and Hainan. The actual distribution of P. pellucida is far narrower than its current maximum range of potential distribution, suggesting that it may continue to spread. Therefore, we should pay more attentions to the harming effects of the weed, strengthen monitoring and integrated management.

Zizania is a cereal species with the closest relationship to Oryza genus in the grass family and is the only genus which is distributed discontinuously between Eurasia and North America in the tribe Oryzeae. Gu (Zizania latifolia) was an important cereal in Chinese history (one of six important cereals in Zhou Dynasty), but it now has disappeared. Another species in Zizania genus, Z. palustris, has been domesticated as a commercial cereal crop in North America in last century. However, no effort has been done in genetic improvement or domestication of Chinese Gu to date. As a part of our effort to recover the ancient Chinese cereal, in this study, the chromosome number of collected Gu was examined by modified carbol fuchsin stain and fluorescent in situ hybridization (FISH). In addition, the main agronomic traits of two semidomesticated Gu (Jiayou 1 and Geshan 1) were investigated, including flowering period, inflorescence structure, seed phenotype and germination rate. The results showed that chromosome number of Gu was 2n=34, which was different from that of Z. palustris (2n=30). The flowering period of Jiayou 1 usually happened in one month from the middle of September to October, which was 15 days earlier than wild Gu and 10 days later than Geshan 1. The ratio of pistillate to staminate flowers was about 1∶1.8 and an inflorescence ideograms of Gu was first drawn. The kilograin mass of brown Gu was about 12.7 g with 9.70 mm length and 1.48 mm width of brown seeds, which were smaller than Z. palustris. Furthermore, the regular arrangement of starch granules was found in the Gu seed by scanning electron microscope. The germination rate of Jiayou 1 seeds could reach 62.9% with an improved seed treatment method. In sum, the semidomesticated Gu, which has a compact plant architecture and normal flowering, provide an important genetic material for the domestication of Gu, although other target traits such as seed shattering need to be improved in future. The ancient crop and its domestication should been given more attention, and more efforts should be taken on artificial mutation breeding.

The spatial distributions of soil properties (e.g., organic matter and heavy metal content) are vital to soil quality evaluation and regional environment assessment. Currently, the spatial distribution of soil properties is usually predicted with classical geostatistics or environmental correlation. These two methods are different in theory. Geostatistics is based on spatial correlation of sampling points. However, it contains some deficiencies, such as the lack of effective utilization of environmental information, the smoothing effect of predicted results, difficult to meet the assumption of single point to multipoint Gaussian distribution etc. On the other hand, the theoretical basis of environmental correlation is based on the relationship between soil and environment, but it ignores the spatial correlation among sampling points. These two methods complement each other. Thus, it is very important to study how to integrate these two methods, so that the spatial correlation among sampling points and the relationship between soil and environmental factors can both be used to improve the prediction accuracy. We propose a new spatial prediction method based on the theory of Bayesian maximum entropy (BME), which is one of the most wellknown modern spatiotemporal geostatistical techniques. The main objective is to incorporate the results of classical geostatistics and quantitative soillandscape model in the BME framework. The result of ordinary Kriging was taken as the priori probability density function (pdf), as well as the sampling data as hard data, and the results of environmental correlation as soft data. Posterior pdf is calculated with priori pdf, hard data and soft data. According to the posterior pdf, the predicted values of nonsampling points could be obtained, which not only contained the spatial correlation between sample points, but also took into account the relationship between soil properties and the environment. Meanwhile, the soil organic matter contents in Jingshan County of Hubei Province were used as experimental data. Six environmental factors closely related with soil organic matter content, including relative elevation (Hr), topographic relief (QFD), slope (β), variable rate of slope (SOS), topographic wetness index (ψ) and surface roughness (M), were used as auxiliary variables to produce soft data for prediction. To evaluate the advantages of this method and to compare with Kriging for different sampling density, the analysis and comparison were conducted on two groups of sampling points, which were a group with high spatial density (group Ⅰ, 330 points) and the other with low spatial density (group Ⅱ, 100 points) respectively. The root mean square error (RMSE) and the relative improvement of the accuracy (RI) are computed from 50 estimation and observation values. The results showed that the prediction of BME had higher accuracy (RI values were increased by 10.95% and 22.72% for group Ⅰ and group Ⅱ respectively) than that from ordinary Kriging, especially in the lowdensity group. Compared with ordinary Kriging, the method proposed in this study has solid theoretical foundation, as it integrates theories of Kriging, environmental relation, and maximum entropy. It is more flexible than Kriging, for example, the parameters used in this method, such as environmental factors and the classification number of predicted variables, can be adjusted according to the users’ needs. Moreover, this method performs better than the ordinary Kriging do for the prediction with fewer sampling points.

Longan (Dimocarpus longana Lour.) and litchi (Litchi chinensis Sonn.) are famous and special fruits in tropical and subtropical zones. Longan and litchi originate in China, which have been cultivated for more than 2 000 years and both hold abundant germplasm resources. There have been many scientific researches on longan and litchi. However, few systematic studies were conducted on comparison of leaf epidermis and pollen grains between longan and litchi. Therefore, the aim of this study is to compare the differences of leaf epidermis and pollen micromorphology among longan and litchi cultivars, and then to study their phylogenetic relationship. The ultrastructures of leaf epidermis and pollen grains from six longan and six litchi cultivars in Western Guangdong Province were examined using scanning electron microscope, and their relationship with the phylogenetic evolution of the genuses was investigated. The results showed that numerous protuberances could be observed on the lower epidermis. The protuberances of litchi were domeshaped, and those of longan were longshaped. There were significant differences in the stomatal densities and sizes of longan and litchi cultivars. The stomatal densities of six longan cultivars were 316.30406.00 No./mm2, while those of six litchi cultivars were 519.00655.20 No./mm2. The stomatal lengths of six longan cultivars were 11.1621.33 μm, while those of six litchi cultivars were 10.3817.28 μm. The pollen grains of longan and litchi were tricolporate, belonged to N3P4C5 type according to Erdtman’s NPC system. These pollen grains were subspheroidal or wide ellipse in equatorial view, and 3lobed subspheroidal or triangle in polar view. The polar axis lengths of pollen grains in six longan cultivars were 18.3119.85 μm, while those in six litchi cultivars were 16.1918.07 μm. The equatorial axis lengths of pollen grains in six longan cultivars was 21.3624.33 μm, while those in six litchi cultivars were 19.2221.47 μm. In addition, there were significant differences in some morphological aspects of pollen grains among longan and litchi cultivars, such as pollen size and colporate. The characteristic differences of leaf epidermis and pollen grains were obvious among longan and litchi cultivars. Thus, it is suggested that the micromorphological characters of leaf epidermis and pollen grains are very important for cultivar differentiation in longan and litchi cultivars. Meanwhile, they can also provide valuable information for the study of taxonomy and phylogenesis among D. longana and L. chinensis cultivars.

Corn is one of the main commercial crops in China, and the increase of its quality and productivity is the key to resolve the current problems of food shortage, resource bottleneck and food security. Raising geese in corn field (hereinafter referred to as RGICF) is a compound production pattern based on the principle of “agropastoral integration”, which was proposed in 2011, and whose core content is compound production model which use the resources such as weeds, bottom leaves of crops, etc. in tillage system to raise poultry. However, there are still some unknown questions to be answered in a systematic way, such as the system productivity, environmental load and sustainability of the system, etc, and these questions must be answered before the popularization of “agro-pastoral integration” technology. Emergy analysis capable of accounting for both economic aspect and the natural contribution to production on a common basis, allowing meaningful comparison across different systems, has been applied in many cases and has been proved to be a powerful tool to assess ecological economic systems and processes, with special focus on the agricultural field. With the purpose of gaining a thorough understanding of the productivity, environmental load and sustainability of RGICF, this study applied the approach of emergy analysis to compare the RGICF treatment with the traditional pattern of corn planting (CK). According to the new development of emergy methodology, the renewability factor of each item was incorporated. Emergy indices such as emergy investment ratio (EIR), emergy yield ratio (EYR), emergy self-supporting ratio (ESR), environmental loading ratio (ELR) and environmental sustainability index (ESI), feedback ratio of yield emergy (FYE), emergy index of product safety (EIPS) and the ratio of output to input were applied to characterize the resource use, production efficiency, environmental impact, the overall sustainability and the economic benefit of the studied systems. The result showed that the EIR and FYE in RGICF were 1.65 and 3.85 times respectively as much as those of CK treatment. In the aspect of environmental load and sustainability, the ELR of RGICF treatment was 2.90 lower than that of CK treatment; and the ESI of RGICF treatment was 20.56 higher than that of CK treatment. In the aspect of product safety, the EIPS of RGICF treatment was 0.41 higher than that of CK treatment. In the aspect of the productivity, the EYR of RGICF treatment was 0.34 lower than that of CK treatment, and the ESR of RGICF treatment was 0.06 lower than that of CK treatment. In the aspect of the economic benefit, because of the high economic input, the ratio of output to input of RGICF treatment was 0.39 lower than that of CK treatment, but the net income of RGICF was 2.02 times as much as that of CK treatment. In conclusion, the pattern of raising geese in corn field is promising in the terms of environmental load, economic benefits and system sustainability, but further improvement is still needed in production efficiency and selfsufficiency.

Mechanized grafting can reduce labor intensity, improve production efficiency and ensure product quality. The majority of researchers choose traditional grafting methods for their grafting machines, such as cutin grafting, joining grafting or split grafting. However, the conventional methods either require multiple steps, quality seedlings, or need external clamping to fix the grafted seedlings, which restrict the grafting speed. In this study, an autografting machine aiming at the Solanaceae was designed based on pingrafting method, which could connect the rootstock and scion with a pin. This method can overcome the limitations mentioned above, because of acting on the aperture disk seedlings directly. The grafting machine was composed of two processing mechanisms: rootstock morphology controlling and scion cutting. The former included three parts: mechanism of location in aperture disk, mechanism of straightening rootstocks and mechanism of clamping rootstocks. The first one, which was designed to control the position of aperture disk during the grafting, was a micropositioner that could jog the aperture forward to the next line of seedlings after completing the grafting task of the current line. The second and third parts worked together to ensure the rootstock in the right posture and clamped six seedlings in each row of the disk during a period, in which the second one was used to correct the rootstocks in vertical direction with two mechanical arms, while the third one played a similar role in transversal direction. These parts were effective, especially when dealing with the untidy growth of tender seedlings. The latter, i.e., the mechanism of rotary cutting was driven by a rotating cylinder. This mechanism had six tool holders of which the blades were installed on the top. It made the incision of scion smooth and flush at a high speed with a determined cutting radius. The results of the performance test indicated that the proposed grafting machine was able to accomplish the clamping task with 97.4% success rate and the cutting task with 94.4% success rate. The prototype machine can work steadily and reliably, which suggests its potential for practical application.

“Chuanchuanxiang” is a kind of hot and spicy chafing dish in which all food material is boiled in strings. The food is accepted widely by consumers because of its convenience and variety. However, published research on microbial contamination of “Chuanchuanxiang” is rare. The aim of this study is to get the message of microbial contamination of this kind of readytoeat food. Seventy samples of “Chuanchuanxiang” were collected from large dining rooms and mini type stalls in a sterile manner. The categories of the samples were classified into aquatic products, meats, vegetables, bean products and eggs. The microbial contamination of all samples in different standards and specifications was analyzed. The indexes detected included the total number of colonies, yeast and mold count, coliform and Salmonella. The main detection method was national food safety standard for aquatic products, meats, vegetables, bean products and eggs. Meanwhile, Filmplate test method was used in the detection of Salmonella. The result of total number of colonies showed that the percent of conformity was 74.3% in all 70 samples. The samples of aquatic products, vegetables and eggs had a qualified rate less than 80% in two kinds of management courts. The qualified rate of aquatic products was only 50% in mini type stalls. The samples of 10% were exceeded the sanitation of coliform from mini type stalls. In the detection of coliform bacteria, filamentous fungi and yeasts, the results displayed that the pollution of vegetable and bean products was more serious. Vegetable samples of 37.5% and 50% were polluted by filamentous fungi and yeasts separately in the two kinds of management courts from large dining rooms and mini type stalls, and the qualified rates of bean products were only 75% and 66.7%. There were differentlevel contaminants of filamentous fungi and yeasts in “Chuanchuanxiang” food of all five categories from mini type stalls. All the results show that the microorganism contamination of the food “Chuanchuanxiang” is serious and the potential damage to health of consumers is probably presented. It is more severe for the food “Chuanchuanxiang” quality in mini type stalls and effective custody would be taken.

Vibrio parahaemolyticus is a Gramnegative, halophilic, asporogenous rod that can move in liquid culture, living in the sea water and seafood. Consumption of raw or undercooked seafood contaminated with V. parahaemolyticus easily lead to foodborne illness. This bacterium is recognized as the leading cause of human gastroenteritis associated with seafood consumption in the United States and an important seafoodborne pathogen throughout the world. The high contamination probability of V. parahaemolyticus has been confirmed in Chinese seafood, especially those from Zhejiang Province. Bloody clam is a traditional shellfish product mainly cultivated in Zhejiang, Guangdong Province. It is popular among Ningbo residents on holiday because of its delicious taste and health benefits. The V. parahaemolyticus will grow and breed along with the growing of bloody clams. In addition, the preference of undercooked bloody clams contribute too much to the probability of foodborne illness. In this study, the occurrence and distribution of V. parahaemolyticus in retail bloody clams from Ningbo was investigated, and the risk associated with bloody clams contaminated by V. parahaemolyticus was also evaluated based on dietary survey using SPSS statistics 19 and @Risk 5.5.0, intending to provide support of food safety strategy and suggestion of bloody clams consumption so that the incidents of foodborne illness can be prevented effectively. It turned out that 37 of 74 samples were contaminated by V. parahaemolyticus, and the contamination density ranged from 0.48 to 3.04 lg(CFU/g). The contamination value above 5 lg(CFU/g) did not exist which was usually used in qualitative assessment. The 56.8% (25/44) of samples from spring were contaminated resulting in V. parahaemolyticus positive, and it was 40% (12/30) for winter samples. Dietary survey showed that consumption frequency for bloody claws ranged between once a week and once a month, and the average dietary intake was 70 g. The exposure of V. parahaemolyticus was located between -2.93 lg(CFU/g) (5%) and 2.07 lg(CFU/g) (95%) averaging in -0.617 4 lg(CFU/g). Sixteen CFU of V. parahaemolyticus might be taken in for average consumption of bloody claws. The risk assessment model predicted the risk of illness for each meal to be 7.38×10-6, the spring and the winter being 6.10×10-5 and 4.07×10-7, respectively. Evaluating the relative affection of all these factors including V. parahaemolyticus negative samples, positive samples, transportation temperature, transportation time using sensitivity model showed that the correlation coefficient was 0.87, 0.47, 0.02, 0.01 respectively, and the control for the original contamination was the first important measure to decrease V. parahaemolyticus food poisoning. In conclusion, the samples from spring have a higher probability of containing V. parahaemolyticus and illcausing than those from winter. The difference during months is not notable. Taking some comprehensive publicity to keep the sensitive subpopulation away as soon as possible is advised, including babies, children, pregnant women, old men and the people with immunity defects; coldchain transportation of seafood should be built to decrease the initial contamination effectively. In addition, educating consumers to learn to distinguish the fresh bloody clams, extend the cook time, avoid crossinfection is very essential for the prevention of foodborne illness.

During food processing and storage, proteins are susceptible to the action of any hydroxyl radicals. Reactive oxygen species (ROS) are naturally generated in food systems. Oxidative processes in food result in decreased quality by causing changes in color, texture, flavor and nutritional value. Currently, many researchers have reported that the proteins are the primary target of oxidizing radicals in vivo. Protein solubility and functional activity reduction were revealed in meat proteins due to simulation oxidation system inducing polymerization and degradation. Furthermore, the effects of metalcatalyzed oxidation systems in fish proteins were also reported. To date, there is no correlation study between protein oxidation and fish allergen. Therefore, the objective of this study was to explore modification of fish muscle proteins by oxidizing radicals, including functional properties such as the allergenicity and functionality groups. To investigate the effects of protein oxidation on the content of carbonyl and sulfhydryl, turbot proteins (allergens) were exposed to a free radical generating system and incubated at 37 ℃ for different intervals. Sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDSPAGE) was used to analyze the alterations of turbot proteins. The alterations of the parvalbumin allergenicity were investigated by Western blot with sera from three fish allergic patients and by indirect enzymelinked immunosorbent assay (ELISA) method with rabbit antiturbot parvalbumin polyclonal antibody. The results showed that 27% proteins were precipitated when exposed to the hydroxyl radical oxidation systems for 5 h. The contents of carbonyl groups in supernatant and precipitate increased by 9.7 and 2.0 times after 5 h oxidation, and sulfhydryl groups decreased by 13.5% and 29.1%, respectively. The electrophoretic patterns of control showed that the contents of 12, 26 and 41 ku proteins extremely decreased. However, the contents of 36 ku proteins increased with increasing oxidative time, which suggests that the aggregates might be formed via noncovalent interactions. IgE Western blot indicated that immunogenicity of proteins decreased with increasing oxidation time. Furthermore, indirect ELISA indicated that the immunogenicity of parvalbumin in both supernatant and precipitate decreased by 16.7% and 31.5% after 5 h oxidation, respectively. It is concluded that the oxidation alters the physicochemical properties of turbot proteins (allergens) and this may lead to the modifications of chemical structure and functionalities of the proteins. The chemical changes occur concomitantly with protein functionalities. However, oxidative damage can also cause important loss of quality. This research could help fish researchers and processors to develop strategies to minimize the oxidation reactions in fish foods during storage and processing.

Tea (Camellia sinensis) is a kind of evergreen shrub or tree, which has been widely planted as an important economic crop in mountainous tropical and subtropical regions of China. Tea gardens are considered both ecologically friendly and economically profitable due to their high plant standing biomass and important role in soil and water conservations. Though it is recognized that the carbon sequestration potential should be huge in the plant and soil of tea gardens, few researches have been carried to quantify their carbon storage and balance. In the tea producing regions of China, tea garden area occupies a large proportion of the total forest area (e.g. 3.1% in Zhejiang Province). Tea gardens might play an important role in the carbon sink of forest ecosystems in those areas. Based on publications between 1950 and 2011 on tea plant growth in China, regression models on the relationship between tea stand biomass and tea plant age or tea yield were established to find out how its carbon storage capacity changes and how much its carbon storage capacity can achieve during a production cycle of a common doublerow tea garden. An exponential growth model was established between tea plant aboveground biomass (Ba) and its age (t): Ba=-14.95+56.3×(1-e-0.27t). Modeling results showed that tea biomass increased rapidly during the first 10 years and then slowly after the first 15 years. Carbon (C) mass of 10 and 15 yearold tea plants was 92% and 98% of that (30.6 t/m2) of 25 yearold tea plants respectively. Carbon accumulation rate was (4.5±0.4) t/(hm2·a) for tea plants of 14 yearold and was (0.95±0.05) t/(hm2·a) for those of 515 yearold. When the shoot/root biomass ratio ranged from 1.68 to 2.34, the C mass of 15yearold tea plants ranged from 31.31 to 28.02 t/hm2. A model for C storage in tea garden was set up based on potential photosynthetic productivity of tea plants and tea yield, thus C storage capacity of tea plants in various tea production regions was estimated. With an efficiency of solar energy utilization of 0.5% currently, the corresponding total C storage was amount to (9.1±1.4) t/hm2 in the tea gardens of China. As for 15yearold tea plants, the C mass of 60 t/hm2 given by the exponential model was close to the theoretical value (56.41 t/hm2) with an efficiency of solar energy utilization of 2%, and the C mass could be up to 70.5 t/hm2 in tea gardens if tea yield was increased. In a word, it is important to quantify the carbon stock through modeling on the changes of biomass C accumulation with tea plant age rather than based on limited field sampling data. It is also noted that plant C pool of tea gardens is one of main agroforestry C pools in tea production regions and tea garden has a high plant C sequestration potential in China.

Two genera, Boerhavia L. (Nyctaginaceae) and Hyptis Jacq. (Lamiaceae), together with five species, Boerhavia repens L. (Nyctaginaceae), Dimeria falcata Hack. (Poaceae), Hyptis suaveolens (L.) Poit. (Lamiaceae), Limnophila rugosa Merr. (Scrophulariaceae), Lolium rigidum Gaudin (Poaceae), are reported as new distributive records to Zhejiang Province of China. The voucher specimens of B. repens, H. suaveolens and L. rigidum are all preserved in Herbarium of Wenzhou University (WZU), and the voucher specimen of D. falcata is preserved in Herbarium of Zhejiang Agriculture and Forestry University (ZJFC), and that of L. rugosa is preserved in Herbarium of Wenzhou University (WZU) and Herbarium of Zhejiang Museum of Natural History (ZJM). These discoveries enrich the content of flora in Zhejiang and provide fundamental materials for studying the plants of Zhejiang.