Abstract:【Objective】To study spatial distribution patterns and sampling techniques for the larvae of rice water weevil, Lissorhoptrus oryzophilus, under seedling throwing transplanting and conventional seedling transplanting in Guangxi, and to provide a theoretical basis for insect survey and integrated control of rice water weevil. 【Method】 The spatial distribution patterns of rice water weevil larvae were investigated by aggregation indices, Taylor’s power principle and Iwao’s regression methods. Different sampling techniques including five-point, linear parallel, double diagonal, checkerboard and zigzag sampling were compared. 【Result】The larvae of rice water weevil had an aggregated spatial pattern and fitted to negative binomial distribution with density dependence under two transplanting methods. The basic components of the distribution were colonies of individuals attracting each other. Different cultivation methods did not change the distribution patterns. The formula of field theoretical sampling based on Iwao’s regression was N=t² (2.256/m+0.240)/D² under seedling throwing transplanting, and N=t² (4.878/m+0.126)/D² under conventional seedling transplanting. The coefficients of variation of rice water weevil larvae in rice field under both seedling throwing transplanting and conventional seedling transplanting were the lowest using double diagonal sampling,which were 63.048 8% and 84.796 0% respectively. 【Conclusion】 Rice water weevil larvae show an aggregated distribution pattern due to their own characteristics as well as environmental factors. The double diagonal sampling was the optimum method to investigate rice water weevil larvae in paddy field under both transplanting methods.

Abstract:【Objective】To separate and identify secondary metabolites of bio-control bacterium strain HN011 in YPD zymotic fluid. 【Method】By a small amount of fermentation (1 L), the zymotic fluid was extracted by using liquid-liquid extraction of petroleum ether, chloroform, ethyl acetate and n-butanol. The active portions were determined by Staphylococcus aureus bioassay. The pure compounds were isolated from the active portions by amplifying fermentation. The pure compounds were identified by NMR and mass spectrometry. 【Result】The bioassay results showed that the activities of different solvent extracts from the zymotic fluid were different. The most obvious activity was ethyl acetate portion, followed by chloroform. The activity of n-butanol portion was weak，and petroleum ether and water portions were not obvious. By amplifying fermentation, fifteen pure compounds were isolated from the bioassay portions, and identified as mainly small molecule cyclic dipeptides based on their structures.【Conclusion】The secondary metabolites，which are produced by bio-control bacterium strain HN011 in YPD zymotic fluid，are mainly small molecule cyclic dipeptides.

Abstract:【Objective】 To set up a method for rapid detection of different provenances, to investigate the genetic diversity, and to provide a theoretical basis for development, utilization and selective breeding of Melia azedarach.【Method】 Twenty SRAP primer combinations (PCs) with relatively high polymorphisms from 783 PCs were selected to analyze the genetic diversity of 37 provenances from all distribution areas nationwide and 1 provenance from Kenya. 【Result】The results showed 242 clear bands were amplified by 20 PCs, among which 101 bands (40.89%) were polymorphic. The number of bands of each PC ranged from 5 to 17, with an average of 12.1. The polymorphism information content (PIC) values of these PCs ranged from 0.188 to 0.488, with an average of 0.299. Thirty-eight provenances could be divided into 7 categories based on UPGMA (with a threshold value of 0.350), and furthermore, by excluding 2 provenances, the rest 36 provenances could be divided into 5 geographic groups. 【Conclusion】SRAP markers can be used to effectively evaluate the genetic diversity of Melia azedarach, and the results of cluster analysis demonstrate clear geographical trends and climatic-ecological characteristics.

Abstract:【Objective】 Single nucleotide polymorphisms (SNPs) within candidate genes involved in growth and resin biosynthesis of loblolly pine， Pinus taeda, were screened and analyzed, preparing technical basis for later marker-assisted breeding.【Method】The candidate unigenes related to auxin, gibberellins, cytokinins or pinene synthesis were selected from loblolly pine cDNA library using bioinformatics. The sequences of eight candidate genes from 36 loblolly pine individuals were aligned and compared using MEGA5.0 and DnaSP4.0 softwares.【Result】 The total length of measured sequences was 5 177 bp. There were 184 SNPs to be detected, and in average there was one SNP site in every 36.9 bp sequence. Among them, 123 were nonsynonymous SNPs and 61 were silent SNPs. The levels of nucleotide diversity for sequenced regions represented by π_a and θ_w were 0.020 and 0.016, respectively. The linkage disequilibrium(LD) of SNPs in the eight candidate genes declined rapidly (R²≤0.2) with the nucleotide sequences increased in length. 【Conclusion】 LD mapping of SNPs in the five candidate genes are useful for loblolly pine breeding.

Abstract:【Objective】 This study aimed to lay a theoretical foundation for cold resistance breeding and to provide a technical support for artificial cultivation of Neolamarckia cadamba．【Method】After the branches of seven provenances were treated with artificially induced low temperature, the contents of methane dicarboxylic aldehyde(MDA), free proline, soluble sugar and soluble protein, the relative electrical conductivity (REC) as well as the branch recovery growth were measured. Using five indicators suitable for determination of cold resistance, combined with principal component analysis and membership function method, the cold resistance of different provenances was comprehensively evaluated. 【Result】Under artificially induced low temperature stress(-2 ℃), the Longzhou provenance had the highest MDA content(35.24 μg·g^-1) and Baoshan had the lowest(21.19 μg·g^-1); Longzhou had the highest proline content (9.98 μg·g^-1) and Dehong had the lowest(6.13 μg·g^-1); Yunfu had the highest content of soluble sugar(79.66 μg·g^-1) and Jinghong had the lowest(65.32 μg·g^-1); Tianhe had the highest content of soluble protein(24.89 μg·g^-1) and Jinghong had the lowest(19.57 μg·g^-1); Baoshan had the highest REC (58.27%) and Yunfu had the lowest(48.37%); During the branch recovery growth, Yunfu had the highest branch bud survival rate(42.03%) and Jinghong had the lowest(3.88%). The integrated indices of cold resistance for seven provenances, Yunfu, Longzhou, Tianhe, Xingning, Jinghong, Baoshan and Dehong were 0.951, 0.863, 0.755, 0.728, 0.191, 0.151 and 0.132 respectively.【Conclusion】The cold resistance of Yunfu provenance was the strongest, followed by Longzhou, Tianhe, Xingning, Jinghong, Baoshan and Dehong. In general, the cold resistance of Guangdong or Guangxi provenance was stronger than that of Yunnan provenance.

Abstract:【Objective】 To establish regression models of soil organic carbon, organic matter and bulk density for forest soils and improve the regional soil attribute database in Lanlingxi watershed, Three Gorges Reservoir area.【Method】Using forest soil survey data of this watershed, the conversion factor for soil organic matter (SOM) to soil organic carbon (SOC) was established, and the regression models linking soil bulk density (BD) and SOM (SOC) content were built. The whole evaluation consisted of determining the coefficient of determination (R²), Nash-Sutcliffe coefficient of efficiency (E), and the percentage error (P_e). 【Result】The Van Bemmelen conversion coefficient (0.58) could not be directly applied in this watershed. The proper SOC-SOM conversion coefficient was 0.455, as SOC-SOD conversion coefficients varied from different depth of soil, declining quickly with the increase of depth. The BD-SOM (SOC) regression models built in other regions could not be directly applied to this region. When parameters of the BD-SOM models were optimized, the logarithm polynomial model could be used for this region. 【Conclusion】Overall, the simulated values of BD-SOM regression models are better than those of BD-SOC models, and it is recommended to use BD-SOM regression models to improve the soil database. Among the optimized BD-SOM models, the recommended model for this study is Federer organic density model with the highest efficiency (E=0.81) and the lowest error (P_e = 5.4%).

Abstract:【Objective】 In order to provide a theoretical foundation and a technical reference for transformation of the low-efficiency forest, the effects of different transformation patterns on the transformation of cypress (Cupressus funebris) funebris forest were investigated.【Method】The spatiotemporal distribution patterns of soil microorganisms and enzyme activities in five cropping patterns　［walnut(Juglans regia，no grass), walnut+chicory(Cichorium intybus), walnut+alfalfa(Medicago sativa), walnut+ orchardgrass (Dactylis glomerata), pure cypress］ in the reform area of cypress funebris forest in Jingyang District, Deyang City were studied.【Result】The quantities of soil microorganisms and enzyme activities both significantly increased after the transformation of the cypress funebris forest. Among the five patterns, the “walnut+chicory” pattern had the most significant effects with the number of soil microorganisms and the contents of catalase, sucrase, urease and alkalinep hosphatase increased by 112.5%，7.7%, 33.0%, 39.1% and 62.9% respectively, and the values of all these factors were significantly higher in the upper layer(0-15 cm)than those in the lower layer(15-30 cm)( P<0.05).There were different seasonal dynamics for three major microorganisms and the activities of four soil enzymes. The quantities of fungi, actinomycetes and bacteria was the highest in summer, spring and autumn respectively, and the catalase activity was the highest in autumn, while the other three enzyme activities were the highest in spring. The total number of soil microorganism was positively correlated with the activities of sucrase and alkaline (P<0.05), and strongly positively correlated with the catalase activity(P<0.01). 【Conclusion】All transformation patterns improved soil fertilities in varying degrees, with the most effective pattern being “walnut+chicory”.

Abstract:【Objective】 To design a collaborative system made up of Unmanned aerial vehicle(UAV) and Wireless sensor network (WSN), which was applied to farmland information monitoring. The function of the system is to provide farm managers with situational awareness of their field and crop by using a WSN linked through a mobile node and carried by a UAV. 【Method】Three independent plots were chosen to build a separate clustering WSN system in which sensor nodes adopted the working cycle of hibernation，wakeup，work and hibernation. The mobile sensor of UAV communicated with the ground sensors along with the UAV flight trajectory to collect farmland data and to transmit the farmland information to the farmland monitoring data center using 3G network.【Result】The system could well complete farmland information collection when the distance between the blocks was more than 100 meters and UAV flight level was 10 meters. The communication quality of UAV-WSN was better than that of static WSN. The average link cost（ALC） dropped by about 10%, 27% and 14% and the average packet loss rate （APLR）reduced by about 24%, 68% and 29% in plot 1,plot 2 and plot 3 respectively. 【Conclusion】The system expands the static WSN transmission distance，improves the energy efficiency and prolongs the life cycle. The results provide a reference for a large area of plain or mountain farmland information collection.

Abstract:【Objective】 To stimulate and predict suspension speed of notoginseng seed particle swarm, and to provide a reference for simulating gas-solid two-phase flow. 【Method】The suspension speeds of seed particles swarm were surveyed by the PS-20 material floating speed test bed. Bench test were stimulated by coupling discrete element method with computation fluid mechanics, and the influences of seed particle swarm volume fraction on the flow field were stimulated. The suspension speed analog values under different volume fractions were validated using the pulanuofusiji modified formula. 【Result】 Volume fractions of seed particle swarm had significant effects on flow field. When the particle volume fraction was zero, the seed particle swarm suspension speeds ranged from 7.14 to 9.32 m·s^-1 and the mean value was 8.23 m·s^-1, while simulation speeds ranged from 7.08 to 9.30 m·s^-1 and average of 8.19 m·s^-1. When particles volume fractions were 2.58%, 3.87%, 5.16% and 7.74%, the simulation results were 8.52, 8.72, 8.96 and 9.46 m·s^-1 respectively,while the theoretical calculated values were 8.53, 8.79, 9.06 and 9.71 m·s^-1 respectively with the maximum error of 2.6%. 【Conclusion】 The particle swarm suspension speed predicted model can be built using stimulated technology when particles volume fraction is below 9.03%. The particle swarm suspension speeds under different volume fractions can be predicted by coupling discrete element method with computation fluid mechanics.