Genetic Parameters Evaluation of Main Reproductive Traits for the New Yorkshire Dam Line with High Prolificacy

The genetic parameters of main reproductive traits for the new Yorkshire line with high prolificacy were evaluated by multiple animal model DFREML The re- suits showed that the heritability evaluates of the total number of born （TNB）, alive number of born （ANB）, litter weigh at birth （LWB） and litter weight at age of 21 days were 0.10, 0.15, 0.09 and 0.14, respectively. The genetic correlations between these traits, for example, the correlations between TNB/ANB, NB/LWB, TNB/LW21, ANB/LWB, ANB/LW21 and LWB/LW21 were 0.87, 0.74, 0.43, 0.69, 0.59 and 0.51, respectively.     

Levels of Germinable Seed in Topsoil and Yak Dung on an Alpine Meadow on the North-East Qinghai-Tibetan Plateau

In order to clarify the interactive mechanism between grazing yak and alpine meadow on the Qinghai-Tibetan Plateau,our study assessed seed density（by species） in the topsoil of alpine meadow with different grazing intensities in the Tianzhu area,north-eastern margins of the Qinghai-Tibetan Plateau and their rates of occurrence in yak dung.Seed density in the topsoil of the lightly grazed,moderately grazed,heavily grazed and extremely grazed alpine meadows in November,2010 were 1 551,1 692,2 660 and 1 830 grains m-2,while in the same meadows in April,2011 densities were 1 530,2 404,2 530 and 2 692 grains m-2,respectively.In the cold season pasture,mean seed density in yak dung from November to April in the lightly grazed,moderately grazed,heavily grazed and extremely grazed sites were 121,127,187,and 120 grains kg-1of dry yak dung.The proportion of total seed numbers in yak dung to soil seed bank in lightly grazed,moderately grazed,heavily grazed and extremely grazed alpine meadow was 1.40,2.62,0.69,and 0.90%.12 species out of the 47 were not found in topsoil but were found in yak dung,10 species out of 45 were not found in yak dung but were found in the topsoil.Endozoochorous dispersal by yaks is therefore very important for soil seed bank and plant biodiversity and population dynamics in alpine meadows.     

Influences of Cold Storage at 5℃ for Different Durations on Oviposition of Female Silkworm Moths

In order to investigate the resistance of female silkworm moths to cold storage and their copulation and oviposition after cold storage, copulation and ovipo- sition experiments of Liangguang 2 silkworms and Guican 1 female silkworm moths were conduced under cold storage at 5 ~C for different durations. The results indi- cated that, after cold storage at 5 ~C with relative humidity of 75%, the resistance of female silkworm moths to cold storage varied with different varieties; to be specific, 9-Fu and 7.Xiang, parent silkworm varieties of Liangguang 2 with ancestry of mul- tivoltinism, were relatively resistant to cold storage, and their copulation capability was still at a high level after cold storage for 72 h. Oviposition capability also varied with different varieties and durations; to be specific, under 5 ~C conditions, between two parent silkworm varieties of Liangguang 2, female silkworm moths of 9-Fu achieved the best results within cold storage duration of 24 h, female silkworm moths of 7.Xiang achieved the best results within cold storage duration of 72 h; be- tween two parent silkworm varieties of Guican 1, female silkworm moths of Xinhang achieved the best results without cold storage, female silkworm moths of 826 achieved the best results within cold storage duration of 48 h.     

Yeast-Derived β-1,3-Glucan Substrate Significantly Increased the Diversity of Methanogens During In vitro Fermentation of Porcine Colonic Digesta

The β-1,3-glucan from yeast has been extensively examined for its immuno-enhancing effects in animals.However,investigation on the relationship among β-glucan,gut microbiota and immune-modulating effects remains limited particularly in pigs.Considering the critical roles of gut methanogens in the microbial fermentation,energy metabolism and disease resistance,we investigated the phylogenetic diversity of methanogens from fermented cultures of porcine colonic digesta with（G） or without（N） yeast β-glucan based on sequences of the archaeal 16S rRNA gene.A total of 145 sequences in the G library were assigned into 8 operational taxonomic units（OTUs） with the majority of sequences（114/145） related to strains Methanobrevibacter millerae or Methanobrevibacter gottschalkii with high identities ranging from 97.9 to 98.6%,followed by 23 sequences to Methanobrevibacter ruminantium,2 sequences to Methanobrevibacter smithii and one sequence to Methanobrevibacter wolinii.The 142 sequences in the N library were assigned to 2 OTUs with most sequences（127/142） related to strains M.millerae or M.gottschalkii with sequence identities ranging from 97.9 to 98.5%,and 15 sequences related to M.gottschalkii with 97.9% identity.Shannon diversity index showed that the G library exhibited significantly higher archaeal diversity（P0.05） and Libshuff analysis indicated the differences in the community structure between the two libraries were significant（P0.0001）.In conclusion,the current study provides evidence that addition of yeast β-glucan significantly increased the diversity of methanogens in in vitro fermented porcine colonic digesta.     

Strategies and Suggestions for the Development of Mechanized Rapeseed Production in Sichuan

Mechanization is the future direction of rapeseed production in Sichuan. A series of technology tests for rapeseed mechanized production have been carried out in terms of variety selection, key agronomic measures and machinery in the main production area of Sichuan in recent years. In the research, the agronomic techniques, including variety selection for mechanical production, key agronomic measures and mechanical harvesting were analyzed. Based on the present condi- tions, strategy and suggestions for the development of mechanized rapeseed produc- tion in Sichuan also were presented.     

Effects of Grafting on Root Exudates of Cucumber and Rhizosphere Environment under Copper Stress

[Objective] This study to aimed to investigate the effects of Cu stress on root exudates and microbial activities in rhizosphere of grafted and ungrafted cucum-ber seedlings, and therefore to elucidate the microbial mechanism of grafting for in-creasing cucumber plants tolerance to Cu stress [Method] Four treatments： （1） un-grafted seedlings ＋ test soil （U0）; （2） ungrafted seedlings ＋ test soil ＋ CuSO4·5H2O （U1）; （3） grafted seedlings ＋ test soil （G0）; （4） grafted seedlings ＋ test soil ＋ Cu-SO4·5H2O （G1） were set in the pot culture experiment. The contents of free amino acids, organic acids, phenolic acid and sugars, microbial population and enzyme ac-tivity in the four treatment were measured, respectively. [Result] The secretion of amino acids and organic acids were increased under Cu stress. The amino acids secretions of grafted seedlings roots were obviously higher than ungrafted seedlings except for Phe and Val. At the same time, the secretion of oxalic acid, malic acid, acetic acid, citric acid, cinnamic acid, ρ-hydroxybenzoic acid and benzoic acid of grafted seedlings were significantly higher than ungrafted seedlings as wel . There-fore, more Cu2＋ were restricted in soil by chelating, complexing and precipitation with root exudates, and its toxicity was decreased. The soil microbial biomass C and N in grafted cucumber rhizosphere were significantly higher than those in ungrafted cu-cumber rhizosphere, whereas basal respiration and metabolic quotient were signifi-cantly lower. Under Cu stress, the numbers of actinomyces and nitrogen fixing bac-teria decreased and the number of fungi increased significantly, whereas there was no significant difference in amounts of bacteria. The numbers of bacteria, actino-myces, and nitrogen fixing bacteria in grafted cucumber rhizosphere were significant-ly higher than those in ungrafted cucumber rhizosphere, but the number of fungi was opposite. The activities of soil urease, phosphatase, sucrase and catalase in grafted cucumber rhizosphere were significantly higher than those in ungrafted cu-cumber rhizosphere. [Conclusion] These indicated that the soil microbial environment and soil enzymes activities were improved by grafting under Cu stress, and as a re-sult, the adaptability of cucumber to Cu stress was improved.     

Genetic Analysis and Molecular Mapping of an All-Stage Stripe Rust Resistance Gene in Triticum aestivum-Haynaldia villosa Translocation Line V3

Triticum aestivum-Hayaldia villosa translocation line V3 has shown effective all-stage resistance to the seven dominant pathotypes of Puccinia striiforms f.sp.tritici prevalent in China.To elucidate the genetic basis of the resistance,the segregating populations were developed from the cross between V3 and susceptible genotype Mingxian 169,seedlings of the parents and F 2 progeny were tested with six prevalent pathotypes,including CYR29,CYR31,CYR32-6,CYR33,Sun11-4,and Sun11-11,F 1 plants and F 3 lines were also inoculated with Sun11-11 to confirm the result further.The genetic studied results showed that the resistance of V3 against CYR29 was conferred by two dominant genes,independently,one dominant gene and one recessive gene conferring independently or a single dominant gene to confer resistance to CYR31,two complementary dominant genes conferring resistance to both CYR32-6 and Sun11-4,two independently dominant genes or three dominant genes（two of the genes show cumulative effect） conferring resistance to CYR33,a single dominant gene for resistance to Sun11-11.Resistance gene analog polymorphism（RGAP） and simple-sequence repeat（SSR） techniques were used to identify molecular markers linked to the single dominant gene（temporarily designated as YrV3） for resistance to Sun11-11.A linkage map of 2 RGAP and 7 SSR markers was constructed for the dominant gene using data from 221 F 2 plants and their derived F 2：3 lines tested with Sun11-11 in the greenhouse.Amplification of the complete set of nulli-tetrasomic lines of Chinese Spring with a RGAP marker RG1 mapped the gene on the chromosome 1B,and then the linked 7 SSR markers located this gene on the long arm of chromosome 1B.The linkage map spanned a genetic distance of 25.0 cM,the SSR markers Xgwm124 and Xcfa2147 closely linked to YrV3 with genetic distances of 3.0 and 3.8 cM,respectively.Based on the linkage map,it concluded that the resistance gene YrV3 was located on chromosome arm 1BL.Given chromosomal location,the reaction patterns and pedigree analysis,YrV3 should be a novel gene for resistance to stripe rust in wheat.These closely linked markers should be useful in stacking genes from different sources for wheat breeding and diversification of resistance genes against stripe rust.     

Induced in vitro Expression of Human Lactoferrin in Goat Mammary Gland Epithelial Cell

[Objective]The aim of this study was to explore the technical system of induced expression in vitro of goat mammary gland epithelial cell,and evaluate expression efficiency of mammary gland specific vector and foreign protein at the cell level.[Method]Goat mammary gland epithelial cell transfected by human lactoferrin gene was inducted by culturing in DMEM/F12 medium supplemented with 5 mg/L insulin,5 mg/L prolactin and 1 mg/L hydrocortisone.Supernatant was collected per 6 hours and concentrated.Expression situation of foreign protein were detected by SDS-PAGE and Western blotting.[Result]There was target protein expression in the induced culture medium,which molecular weight was about 42 kD.[Conclusion]The method used in this study can induce goat mammary gland epithelial cell to express foreign gene,it lays a foundation for researching heterologous expression of foreign gene and producing mammary gland bioreactor.     

Correlation Analysis of SPAD Value with Chlorophyll Content and Economic Yield Traits of Brassica napus L.

[Objective] The aim was to compare differences of SPAD value, chloro- phyll content, agronomic characters, economic characters and yield traits to analyze correlation of SPAD value with other indices and establish regression functions. [Method] Based on 34 Brassica napus L. varieties, SPAD value, chlorophyll content, agronomic characters, economic characters and yield traits were measured and re- gression functions were established according to correlations. [Result] SPAD value, chlorophyll content, agronomic and economic characters and yield traits all achieved significant level in differences among 34 varieties. Specifically, SPAD value was of extremely significant correlation with chlorophyll a and b, total chlorophyll and carotenoid, and the correlation from high to low was chl-b〉chl-z〉chl-a〉chl-x. SPAD value was of significantly positive correlation with total pod number per plant, plant height, seed number per pod, yield per plant and harvest yield, and of insignificant correlation with branch point height, effective branch number, pod density of main stem, and pod length. [Conclusion] It is simple and rapid to predict chlorophyll con- tent, economic characters and yields of Brassica napus L. with SPAD value and re- gression functions.     

Effects of SSA Dosages on Seedling Quality and Yield by Mechanical Transplanting

[Objective] The aim was to research the influence of gradient dosages of seedling-strengthening agent （SSA） on rice seedling quality and yield. [Method] The influence of four dosages of SSA on late rice seedling quality and yield was investi- gated, using Oryza sativa cv. Yongyou 9 and Huanghuazhan as test materials. [Re- sult] The results showed that applying SSA significantly increased several indexes of seedling quality including the leaf age, basal stem width and dry matter weight. In addition, SSA greatly increased the rice yield, mainly through influencing two yield component factors, effective panicle number and grain number per panicle. [Conclu- sion] SSA was beneficial to nurse strong seedling which satisfied mechanical trans- plant and improve yield. Considered both seedling quality and yield trait, the optimal SSA dosage is 50 g/m2 under this cultivating condition.     

Stk2,a Mitogen-Activated Protein Kinase from Setosphaeria turcica,Specifically Complements the Functions of the Fus3 and Kss1 of Saccharomyces cerevisiae in Filamentation,Invasive Growth,and Mating Behavior

Setosphaeria turcica,an essential phytopathogenic fungus,is the primary cause of serious yield losses in corn; however,its pathogenic mechanism is poorly understood.We cloned STK2,a newly discovered mitogen-activated protein kinase gene with a deduced amino acid sequence that is 96% identical to MAK2 from Phaeosphaeria nodorum,56% identical to KSS1 and 57% identical to FUS3 from Saccharomyces cerevisiae.To deduce Stk2 function in S.turcica and to identify the genetic relationship between STK2 and KSS1/FUS3 from S.cerevisiae,a restructured vector containing the open reading frame of STK2 was transformed into a fus3/kss1 double deletion mutant of S.cerevisiae.The results show that the STK2 complementary strain clearly formed pseudohyphae and ascospores,and the strain grew on the surface of the medium after rinsing with sterile water and the characteristics of the complementary strain was the same as the wild-type strain.Moreover,STK2 complemented the function of KSS1 in filamentation and invasive growth,as well as the mating behavior of FUS3 in S.cerevisiae,however,its exact functions in S.turcica will be studied in the future research.     

Resistance to the Whitefly Aleurotrachelus socialis（Hemiptera：Aleyrodidae） and SSR Marker Identification in Advanced Populations of the Hybrid Manihot esculenta subsp.Manihot flabellifolia

Genes resistant to Aleurotrachelus socialis were transferred to the F 1 from the interspecific hybrid wild species of Manihot flabellifolia to M.esculenta and two advanced generations of backcrosses（BC 1 and BC 2）.We characterized the resistance of A.socialis transferred to BC 2 parents（CW67-160,CW67-130,CW67-44）,MTAI-8（BC 1）,resistant（CMB9B-73） and susceptible（CMB9B-104） genotypes from contrasting pools,and resistant（MEcu-72） and susceptible（CMC-40） genotypes.Whitefly demography and biology were evaluated.SSR molecular markers associated with a phenotypic response of plant resistance were detected in segregating populations（BC 2）.Results showed that although female survival time was similar on all hosts,the lowest averages of longevity,fecundity and oviposition rate were observed in the resistant control MEcu- 72,only being significantly similar to the parent CW67-130.When the BC 1 and BC 2 populations were compared,it was found that A.socialis fecundity was eight times lower on CMB9B-73 progeny than on CW67-130,expressing the highest levels of resistance to the whitefly.Ten genotypes of CMB9A and CMB9B family had the best segregation.A total of 486 microsatellite primers were evaluated using bulked segregant analysis（BSA）,11 showed polymorphism between the contrasting pools and only one showed significant differences between resistant and susceptible individuals.In conclusion,fecundity was the parameter that impacted most on the intrinsic rate of A.socialis population growth.     

Statistical Analysis of Regularity of Pesticide Residues in Vegetables Produced in Inner Mongoli

[Objective] The paper was to study regularity of pesticide residues in veg- etables produced in Inner Mongolia. [Method] Mathematical statistic analysis was carried out on 6 800 samples of veggies, fruits, leguminous vegetables, nuts and seeds produced in Inner Mongolia. [Result] The dominated vegetables in Inner Mon- golia were green leafy vegetables, solanaceous vegetables and melon vegetables, and their yields accounted for 70% of the total vegetables production. Since 2003, with the rapid increase of detected vegetable numbers, the status of vegetable qual- ity safety had entered into a new stage of sustainable steady after a rapid decline or periodic fluctuation, and the differences in safety levels were obvious, of which the range of exceeding standard rate of pesticide residues in solanaceous vegeta- bles, melon vegetables and leguminous vegetables （about 55% of the total vegeta- bles） was under 2%, with average values of 1.1%, 1.6% and 3.1%, respectively. They belonged to stable type. The exceeding standard rate of pesticide residues in green leafy vegetables and Chinese cabbage group （about 30% of total vegetables） presented a decreasing trend year by year, wondering in the range of 7%-10%. They belonged to main risk type. The time period of exceeding standard of pesticide residues in root vegetables and cole vegetables was under predictable, and its ex- ceeding standard rate in some years was over 5% （amplitude variation is over 15 percentage points）. They belonged to random risk type. The kinds of pesticides, which exceeding standard rate in vegetables were relatively intensive, presented vari- ance in different vegetable species. 70% of the pesticides belonged to intermittent over-limits and the probability was below 5%. About 20% tradition pesticides often exceeded standard and their probabilities were over 30%. The exceeding standard of organophosphorus and carbamates pesticides in vegetables presented a decreasing tend, while the risk of some new pesticides containing nitrogen element and high effective pyrethroids showed an increasing tendency. [Conclusion] The paper provid- ed decision making services for agricultural management departments.     

Research Progress and Identification Method of Apple Stress Resistance

In the research, changes of apple chemistry, and molecule, under stresses, are n terms of morphology, physiology, bio- illustrated and research and identifica- tion methods of apple resistance are explored involving drought-resistance, flood-re- sistance, salt-stress resistance, cold-hardiness and heat-resistance. In addition prospects of apple resistance research are proposed, as well.     

Characterization of Soil Available Nitrogen in the Major Vegetable Production Areas of Pearl River Delta,China

A macro scale survey was performed to investigate the content of soil available nitrogen （N） and its spatial distribution in the main vegetable production areas of the Pearl River Delta.Preliminary enrichment-deficient index of available N was then developed,which was a base for increasing fertilizer application efficiency and vegetable yield as well as for constructing soil testing and fertilizing formula.In general,most of the vegetable growth areas in Pearl River Delta were N-deficient or medium-N-deficient.There was 30%-62% increase in yield of Chinese cabbage on the N-deficient soil after application of N; when soil available N content was less than 145 mg/kg,the yield increased with application of N fertilizer at a rate of 60-70 kg/hm^2.     

Screening of Toxin Mutant of Dickeya zeae and Its Biological Characters

[Objective] This study aimed to screen toxin mutant of Dickeya zeae （Er- winia chrysanthemi pv. zeae） and investigate its biological characters. [Method] We obtained a toxin mutant strain D. zeae Ech7-3-42 by using acridine orange as a mutagenic agent and compared their biological characteristics and virulence between the toxin mutant and wild strain. [Result] There was no significant difference in pectin lyase, protease, cellulase and the production of extracellular polysaccharide and lipopolysaccharide, but significant difference in toxin biological activities and vir- ulence. Ech7-3-42 mutant did not produce toxin, as well as the loss of virulence on rice and HR on tobacco, but did not lose the ability to soft rot on potato. Mutant strain Ech7-3-42 can infect rice root and then enriched in the root neck and stalk, but it could not cause rice foot rot. Dickeya zeae （wild and mutant strain） could be detected by PCR in the root neck and below the 1-2 cm long stem area, but could not be detected in the leaves. [Conclusion] We believed that toxin may be one of the important factors for D. zeae virulence on rice.     

A Review on Tibetan Swine（a） Carcass,Meat Quality,Basic Nutrition Component,Amino Acids,Fatty Acids,Inosine Monophosphate and Muscle Fiber

In this review, the carcass, meat quality, internal organs, basic nutrition component, amino acids （AAs）, fatty acids, inosine monophosphate （IMP） and mus- cle fiber of Tibetan swine were summarized for the first time. The formation mecha- nism of excellent features was analyzed from the aspects of physiological traits, ge- ographical environments and constraint reasons. Thereby, the outstanding features of Tibetan swine could be extended continuously, and the poor characteristics should be improved in the future.     

Pattern Change and Regional Disparity Tendency of Cultivated Land Use in Jiangsu Province

The study has examined the tempo-spatial patterns of cultivated land use change in Jiangsu province. A principal component analysis （PCA） of 18 selected indicators of cultivated land use during the period 1970-2010 identified 2 main pat- terns of change in planting productivity and economic efficiency. A major shift from production-centered pattern to profit-oriented one occurred in 1984, the time of grain yield surplus and the mitigation of population pressure. In response to the impending Opened Market System, there was a notable tendency of higher efficiency and less productivity since 1997, as well as remarkable regional disparity of cultivated land use change spatially. It revealed a relative decrease in grain cropping share, crop- ping scale and cultivation intensity in South Jiangsu, especially in Tai-Lake region, and the reverse in North Jiangsu. Some suggestions for the future were finally dis- cussed from the above findings.     

Potential Geographic Distribution of Oriental Fruit Fly in Jiangxi Province

[Objective] The aim was to effectively monitor and manage oriental fruit fly.[Method] Maxent model and ArcGIS were used to predict potential geographic distributions of the oriental fruit fly based on associations between known occurrence records and a set of environmental variables.[Result] The suitable areas for Bactrocera dorsalis infestations were mainly restricted to central and southern Jiangxi Province,with Latitude ranged from 24 to 28°N.Northeast Jiangxi,Northwest Jiangxi and the regions bording upon Yangtse River were predicted as unsuitable for Bactrocera dorsalis.The fit for the model as measured by AUC was high,with value of 0.978 for the training data and 0.965 for the test data,indicating the high level of discriminatory power for the Maxent.A jackknife test in Maxent indicated that mean temperature of coldest quarter with highest gain value was the most important environmental variable that restricted the expansion to north Jiangxi Province.[Conclusion] Further research into the biology of the species and their ability to overcome barriers was necessary to explain niche differentiation and better understand invasion risk.