HU Jing , CHENG Gang , TAN Yan-ping , WANG Chun-tai , LIU Xue-qun
2010, 29(3):257-261. DOI: 1000-2421(2010)03-0257-05
Abstract:The recombinant prokaryotic expression vector pTYB1orf216 with the intein tag was constructed and transformed into E.coli ER2566.The optimized protein expression induction condition in E.coli was 0.8 mmol/L IPTG (isopropy-β-D-thiogalacto side) at 15 ℃ for 15 hours.A band with 85 ku of molecular weight was observed on SDSPAGE,and the protein was mainly existing in the soluble composition.This protein was isolated and purified through affinity chromatography,and then polyclonal antibody was prepared.The results of Western blot indicated that the prepared polyclonal antibody was with high specificity.
DONG Fa-ming , HONG Deng-feng , LIU Ping-wu , XIE Yan-zhou , HE Qing-biao , YANG Guang-sheng
2010, 29(3):262-267. DOI: 1000-2421(2010)03-0262-06
Abstract:The genetic model of a rapeseed recessive genic male sterility line 9012AB was reevulated by traditional genetic analyses.Genetic analysis results showed that the male sterility of 9012A is controlled by two individual loci,i.e.Ms3and Rf.There are two alleles at the Ms3locus,the dominant wild type allele Ms3 is the fertile allele,while its recessive allele ms3 the sterile one.Three alleles are found at the Rf locus,individually Rfa> (mutation restoration allele),Rfb> (mutation sterile allele) and Rfc> (wild type fertile allele),with the dominance relationship of Rfa>>Rfb>>Rfc>.According to this new model,the genotype of 9012A,9012B and its temporary maintainer line T45 is Ms3ms3RfbRfb,ms3ms3RfbRfb, and ms3ms3RfcRfc,respectively.Similarly,the genotype of restoration line is Ms3 Ms3 _ _或_ _RfaRfa.
2010, 29(3):268-271. DOI: 1000-2421(2010)03-0268-04
Abstract:Potato plants were treated with signal molecules SA,MJ,ETH and ABA.The leaves were sampled at different time points and the total RNA was extracted for semi-RT-PCR analysis.The relative expressions of Star gene under the four signal molecules were analyzed.The results showed that Star gene could be rapidly induced by SA,MJ and ABA but slowly by ETH.The expressions of Star gene induced by the four signal molecules were widely overlapped,suggesting that this gene could take part in a very important process of signal transmission in response to Phytophthora infestans infest.
LI Ming-hai , YANG Ying-qing , YANG Mei , ZHOU Er-xun
2010, 29(3):272-276. DOI: 1000-2421(2010)03-0272-05
Abstract:To further elucidate the mechanism of Jinggangmycin in controlling rice sheath blight,effects of Jinggangmycin on three cell wall degrading enzymes(CWDEs),i.e. polygalacturnase(PG),cellulase(Cx) and pectin methylgalacturonase(PMG),and soluble mycelial proteins of Rhizoctonia solani,the causal agent of rice sheath blight, were investigated in this research. The results showed that the enzyme activities of all three CWDEs decreased in different degrees at all three tested concentrations of 20, 100,500 μg/mL of Jinggangmycin compared with the blank control(absence of Jinggangmycin,the same in later text). Jinggangmycin at the concentration of 20 μg/mL or 100 μg/mL caused significant reduction at P=0.05 level in enzyme activity of Cx or PG,respectively,when compared with the blank control; however, there was no significant difference at P=0.05 level in enzyme activity of PMG at different concentrations of Jinggangmycin compared with the blank control. By using polyacrylamide gel electrophoresis technique, soluble mycelial proteins of each treatment displayed a pattern of 20 proteinbands with 16 clearer ones when the pathogen was cultured at above mentioned three concentrations of Jinggangmycin. The numbers and the mobility rates of proteinbands were identical, whereas the colour darkness and band width were somewhat different compared with those of the blank control, indicating that the kinds of protein were the same, but the protein contents were different; the band with molecular weight of 90 ku was obviously strengthened at 500 μg/mL, whereas the 6 bands with molecular weights between 16 u and 35 u were obviously weakened at the same concentration,which indicated that Jinggangmycin had certain effect on the soluble mycelial proteins at 500 μg/mL,but no significant effects on the soluble mycelial proteins were observed at concentrations of 20 μg/mL and 100 μg/mL. Taken all together,our study revealed that Jinggangmycin had an impact on CWDEs and soluble mycelial proteins of R.solani weakened the infection of R.solani to rice,and thus it is speculated that this may be one of the mechanisms of rice sheath blight control of Jinggangmycin.
HUAI Yi-jun , TAN Jia-jin , YE Jian-ren , QU Hong-ye
2010, 29(3):277-281. DOI: 1000-2421(2010)03-0277-05
Abstract:During 2007-2008,a preliminary survey of rhizosphere parasitic nematodes of poplar tree was carried out in Jiangsu Province.By means of morphological characteristics and measurement values,9 species,7 genus of poplar tree rhizosphere parasitic nematodes were identified,i.e.Filenchus australis,Filenchus orbus,Helicotylenchus digitiformis,Scutellonema brachyurus,Paratylenchus minutus,Aphelenchus isomerus,Aphelenchoides limberi,Aphelenchoides bicaudatus and Xiphinema americanum. Except for Aphelenchus isomerus,poplar tree was new host plant for the other 8 species of nematodes.
WANG Long-jiang , LU Li-hua , XIE Mei-qiong , HE Yu-rong
2010, 29(3):282-286. DOI: 1000-2421(2010)03-0282-05
Abstract:Solenopsis invicta Buren(red imported fire ant,RIFA) was one of the most dangerous and devastating invasive pests in the world. In this paper, the changes of the activities of superoxide dismutase(SOD), catalase(CAT), peroxidase(POD), carboxylesterase(CarE) and acetylcholinestrease(AchE) in red imported fire ant workers infected by Beauveria bassiana were studied, which provided the theoretical basis for the research on red imported fire ant infected by Beauveria bassiana and the pathogenic mechanism. The results showed that the activities of SOD,CAT and POD in infected red imported fire ant workers’ bodies had changed in different degrees. 12 hours after the inoculation,the activities of SOD and CAT of infected red imported fire ant workers revealed significant difference in contrast to the untreated ones,and their enzyme activities were significantly lower than those of the controls,their POD activity was first went up and then went down; 36 hours after the inoculation,the activity of 12.33 U3 was significantly higher than that of the control group, which was 10.13 U3, but then it went down. The activity of CarE in 36 hours after inoculation was the lowest,which was 6.55 U4, greatly different from the 8.15 U4 of the control group. The activity of AchE went up at first and then went down,and reached the highest point at 9.24 U5 36 hours after the inoculation,which was significantly higher than the 6.65 U5 of the controls.
CHEN Gui-hua , LI Jing-bo , CAI Hai-lin , BAI Lian-yang
2010, 29(3):287-291. DOI: 1000-2421(2010)03-0287-05
Abstract:Preliminary study on the active component of Radix peucedani capable of inducing rice resistance to blast was carried out by tracing bioassay. The acetone extract showed better inducive effect on the resistance to rice blast disease(Magnaporthe grisea) compared to other solvent extracts. The acetone extract was isolated by silica gel column chromatography. The fractions A4, A5, A6 were more active than others.The effects of inducing resistance of the three fractions at different concentrations were 21.48%~59.54%, and in the three tested concentration range of quality,the effects were higher at the lower concentrations.
FENG Yan , YANG Jing-mei , WANG Xiao-rong , LIN Jia-xuan , XIA Gong-shu , LIU Kai-qi
2010, 29(3):292-294. DOI: 1000-2421-(2010)03-0292-03
Abstract:Juice was squeezed from the root,basal part of stem and leaf of fresh Allium tuberosum and Allium fistulosum. With the methods of plate confrontation and addition,its inhibition on mycelium growth and spore germination of Fusarium oxysporum f.sp.cubense Race 4 were studied. The results showed juice from different parts of both Allium tuberosum and Allium fistulosum with various concentrations had some inhibition to the mycelium growth of Fusarium oxysporum f.sp.cubense after being treated for seventy two hours with plate confrontation. The inhibition effect of Allium tuberosum stem juice was 63.18%,on the top of the list. With the method of addition,the inhibition of Allium tuberosum juice was highly significant,all over 94%. Most important of all,the inhibition effect of stem was the best,up to 100%.The inhibition of Allium fistulosum leaf juice was also 100%.The spore germination rate was 0 as the juice concentration was over 55% for all parts of the two plants.
ZHU Wen-da , CAO You-cheng , TU Shu-xin , YUAN You-min , WANG Ming-rui
2010, 29(3):295-299. DOI: 1000-2421(2010)03-0295-05
Abstract:A field experiment was carried out to study the damage of Eupatorium adenophorum Spreng to garlic yield and its economic thresholds. The optimum regression model for the garlic yield loss and the density of Eupatorium adenophorum Spreng weed was established and the competitive mechanisms of nutrients and water to affect effecting garlic yield were discussed. The results showed that the garlic yield decreased significantly with the increasing density of weeds. The hyperbola model(1/y=-0.018 286+0.435 75/x,F=261.79**) could well fit the relation between the garlic yield loss(y) and the weed density(x). The economic infestation levels for the Eupatorium adenophorum Spreng by manual weeding, 10% Glyphosate and 24% Picloram were 2.630%, 0.277% and 0.369% respectively, and the economic threshold were about 1.09, 0.12 and 0.16 plant per m2 respectively.
WANG Wen-qi , WANG Jin-jun , ZHAO Zhi-mo , ZHANG Wei
2010, 29(3):300-305. DOI: 1000-2421(2010)03-0300-06
Abstract:Based on the mild,moderate and severe communities of Eupatorium adenophorum,the structure,species composition and diversity of the plant community in the abandoned arable land of Dechang county,Sichuan province was investigated comparing with the structure characteristics of Eupatorium adenophorum.The results showed that in mildly occurred sites,the internal diversity index of this plant community varied slightly from 0.550 1 to 0.683 3; in moderately occurred sites,that decreased from 0.639 3 to 0.333 5; in the severe sites,Eupatorium adenophorum formed a regional communitygifted.The spreading of Eupatorium adenophorum in mild growth sites was relatively slow,the community was distributed fascicularly and sporadically,the density increased from 3 stems/m2 to 8 stems/m2 after a year,the coverage expanded from less than 5% to near 10%; The density of Eupatorium adenophorum in moderate sites increased from 32 stems/m2 to 103 stems/m2 in the following year and the coverage expended from less than 35% to more than 90%; the coverage,density and height of Eupatorium adenophorum in severe sites reached to the maximum,and accompanying plants were quite rare in the same period.
WANG Yue-rong , ZHOU Jin-xing , ZHOU Zhi-xiang , SUN Qi-xiang
2010, 29(3):306-311. DOI: 1000-2421(2010)03-0306-06
Abstract:Based upon the case of Qianlianghu polder in the Dongting Lake region,soil physical properties of bulk densities,porosities,water contents,compositions and fractal characteristics of soil aggregates was studied and evaluated synthetically through gray incidence analysis in five typical patterns of land use under converting polders back into wetlands,which included forestland (Ⅰ),garden land (Ⅱ),dry land (Ⅲ),paddy land (Ⅳ) and waste land (Ⅴ).The results showed that soil bulk densities,capillary porosities,non-capillary porosities,total porosities,soil natural water contents,soil capillary moisture capacities,mean weight diameters and fractal dimensions of soil aggregates in 0~50.0 cm soil layers under different patterns of land use were 1.02~1.65 g/cm3,33.04%~61.70%,2.15%~25.35%,38.40%~64.96%,17.07%~38.33%,23.22%~64.00%,1.76~5.09 mm and 2.272 8~2.638 8,respectively.The biggest variation coefficient (83.51%) was existed in noncapillary porosities and the smallest (3.61%) in fractal dimensions of soil aggregates in all soil physical indexes.In 0~25.0 cm and 25.0~50.0 cm soil layers,the waste land had the highest soil bulk densities,the lowest non-capillary porosities,total porosities,soil natural water contents and soil capillary moisture capacities,and its capillary porosities were higher than that of garden land.The order of gray incidence degrees of soil physical properties were Ⅱ (0.776 3) >Ⅳ (0.762 1) >Ⅰ (0.698 6) >Ⅲ (0.659 2) >Ⅴ( 0.618 3),which showed that the soil physical characteristics was the poorest in waste land than that in other land use patterns.
WANG Qiao-lan , WU Li-shu , ZHAO Zhu-qing , HUANG Li-min
2010, 29(3):312-316. DOI: 1000-2421(2010)03-0312-05
Abstract:15N tracer method was adopted to study the effects of different nitrogen forms (NH4+-N,NO3--N and NH4NO3) on the N loss of rice plant under the solution culture,and the factors affecting the N loss were analyzed.Firstly,rice seedlings were cultured in nutrient solution and fed with 15N (abundance 10%) for two weeks,and then transferred to the nutrient solution culture with different nitrogen forms for 10 d.The results showed that the rice with application NH4+-N had the highest biomass and the largest amount of N loss with the N loss rate of 17.06% compared with other nitrogen forms.The rice supplied the complex nitrogen source (NH4NO3) had no significant differences in biomass compared with that of NH4+-N,but the N loss rate decreased significantly with only 9.96%.The results indicated that the application of NH4NO3 decreased N loss of rice plant,and improved the nitrogen utilization efficiency without affecting the rice growth.In addition, NH4+ content,GOT activity and pH values of rice leaves applied with NH4+-N were higher than other nitrogen forms,indicating that ammonia volatilization resulted from the increase of NH4+ content of plant may be the main cause of the N loss of the plant.
ZENG Chang-di , YU Min , XIAO Hong-dong , WANG Hui-zhen , XIE Hai-sheng , ZENG Xue-feng
2010, 29(3):317-320. DOI: 1000-2421(2010)03-0317-04
Abstract:Soluble sugars,free amino acids and proline were determined in tifdwarf(Cynodon dacytlon × C.transvaanesis)and seashore paspulum(Paspulum vaginatum Swarfz)under Si addition and shading treatments in media culture to study the influences of Si on the shading tolerances of turfgrasses.The results showed that content of total soluble sugars,sucrose and reductive sugars were significantly (P<0.05) decreased,while free amino acids were significantly (P<0.05) increased after shading treatment in tifdwarf and seashore paspulum.The differences between CK and shading decreased after Si application.Content of proline was significantly (P<0.05) increased by Si application but decreased less by shading.The content of total soluble sugars,sucrose,free amino acids and proline were significantly (P<0.05) higher in tifdwarf than that in seashore paspulum.Less effect was observed in tifdwarf than that in seashore paspulum after Si addition and shading treatments.These results indicated that the non structural carbohydrates dropped under shading stress which was restored by the higher energy utility induced by Si deposition,thus Si enhanced the shading tolerance of turfgrass.The results also showed that the shading tolerance of tifdwarf was higher than that of seashore paspulum.
LEI Hong-ling , LU Hai-bo , CAI Jin-zhou , QIU Song , ZHENG Xiao-jiang , LI Shi-rong
2010, 29(3):321-325. DOI: 1000-2421(2010)03-0321-05
Abstract:Ampelopsis grossedentata is a kind of medical0edible plant with many medical and health care functions.In order to explore the effects of selenium on growing development,physiological-biochemical characteristic of A.grossedentata,Na2SeO3 was sprayed on the leaf of potted A.grossedentata with different concentration ( 0,50,75,100,125,150 and 175 mg/L ).The effects of selenium on the content of selenium and the activity of antioxidase,the dynamic variation of soluble protein,free amino acid,soluble sugar and flavone in A.grossedentata were studied.The results showed that when the concentration of selenium was lower than 100 mg/L,the higher the concentration is,the higher the selenium content was.When the concentration of selenium was ranged from 100 to 175 mg/L,the content of selenium in A.grossedentata has no significant change.The activity of GSH-Px could be promoted by selenium,and reached to maximum when the concentration of selenium was 125 mg/L.The activitiy of APX and CAT could be promoted when the concentration of selenium was lower than 125 mg/L.However,the activity of SOD could not be promoted in low concentration of selenium.When the concentration of selenium was ranged from 75 to 125 mg/L,the content of soluble protein,free amino acid,soluble sugar and flavone in A.grossedentata were increased.The activity of antioxidase and the synthesis of effective ingredient in A.grossedentata can be promoted with suitable concentration of selenium,and the optimum spraying concentration of selenium is 100 mg/L.
LIU Ke-qun , CHEN Zheng-hong , ZHOU Jin-lian , LIU Min
2010, 29(3):326-332. DOI: 1000-2421(2010)03-0326-07
Abstract:According to the ground weather observation data from l960 to 2007 at 71 weather stations in Hubei Province and the drought and flood disaster-affected and disaster-suffering area data,the drought and flood index of Hubei Province was proposed based on single station index often used in Hubei Province.Factors such as the variation characters of drought and flood,the disaster-affected area,the disaster-affected rate (the ratio of the disaster-affected area to total planting area),the disaster-suffering rate (the ratio of the disaster-suffering area to total disaster-affected area),the meteorological disasters index of drought and flood and the rice planting percentage in Hubei Province were analyzed by using the least square method.The results showed that the main flood season of Hubei Province is from June to August,in which more than 85% of medium flood and more than 90% of serious flood ocurred,and that the drought may occur in once a month potentially.Because the most important farming season in Hubei Province is from April to September,the drought during this period has the greatest influence on the local agricultural production.In conclusion,the meteorological disasters of drought and flood in Hubei Province occur every year in different degree.The serious flood occurs one time every 3 years and the serious drought occurs one time every 4 years in recent 50 years.Though the annual trend of the drought and flood index is ambiguous,the increasing tendency of the disaster-affected area and the disaster-suffering rate is obvious.On one hand,the agricultural planting structure has changed,namely,the rice planting area decreased while the dry land area increased relatively.This change enhanced the waterlogging degree of dry land crops due to the rice having a good waterlogging tolerance and being able to store water.On the other hand,the farmland water conservancy facilities are aging and the riverway is being silted up.
LIU Wang-hong , HU Jun-yong , NI De-bin , PAN Wan-ping , XIONG Yuan-zhu
2010, 29(3):335-340. DOI: 1000-2421(2010)03-0335-06
Abstract:In this paper,the authors carried out continuous measurements on the growth performance of three leantype breeds,Duroc,Landrace and Yorkshire (30~50 kg and 30~100 kg),and explored the optimal fitting model to study the early development.The regression analysis in variety conditions,between the early age and weight,weight and back fat,with nonlinear model and linear models,such as Logistic,Gompertz,Saturation,Quadratic and Polynomial etc,were analyzed based on the testing data of 678 pigs in five typical pig farms of Hubei Province.The results showed that,the three modles (Logistic,Gompertz,and Saturation) in a certain range are all suitable for researching on the growth development on age and weight of lean pigs.In meaning of the biological sense,Gompertz model is better than the Logistic model.While the Saturation model can get a good and simple fit.And this model didn’t change transformation of metatype,with the advantages of developing revision formula.Logistic and the Gompertz model is not suitable for study on weight and backfat development law,while Saturation model has good biological sense in the development law of weight and back fat,and within the limits of the growth phase of any weight,has continuous point forecast function about the back fat.So,the Satuartion model is the most suitable fitting model.
TIAN Tian , HU Huo-geng , CHEN Chang-fu
2010, 29(3):341-345. DOI: 1000-2421(2010)03-0341-05
Abstract:This paper reported the fulminant haemorrhagic disease of bluntnose black bream(Megalobrama amblycephala)in Jiangxi,China.The typical symptoms of the disease included:decay in the end of dorsal and caudal fins; congestion and hemorrhage in skin; muscle and intestines with ascites.Two kinds of bacteria were isolated from the sick bluntnose black bream with typical syndrome and were proved to be its pathogen by artificial challenge.The pathogens were identified as Aeromonas hydrophila and Aeromonas sobria by morphological observation and biochemical test.The antibiotic sensitivity analysis showed that vancomycin,amikacin,tobramycin,kanamycin,cefradine,cefoperazone,cefazolin,piperacillin and norfloxacin were sensitive to Aeromonas hydrophila and Aeromonas sobria;A.hydrophila and A.sobria were resistant to gentamycin,ceftriaxone,ceftazidime and cotrimoxazole.
HUANG Hui , MAO Zhi-juan , CHEN Ji-gang
2010, 29(3):346-350. DOI: 1000-2421(2010)03-0346-05
Abstract:According to OmpU gene sequence published in GenBank,primers were designed and the DNA fragment of about 1 000 bp was amplified by PCR from genomic DNA of Vibrio Harveyi ZJ2008,isolated from disease Pseudosciaena crocea.The gene was cloned into pMD18-T vector and sequenced,then submitted to GenBank with an accession number FJ919231.BlastN result showed that the sequence shared identity of 99.0% with OmpU of Vibrio harveyi.The sequence was subcloned into pET-30a resulted with the recombinant plasmid pET30aOmpU which was further transferred into host bacteria E.coli BL21(DE3) with IPTG induction for expression.SDSPAGE profiles showed the expected MW of the recombinant OmpU was around 41 ku.The protein was expressed in the form of insolvable fusion bodies and was preliminary purified by urea method.Forty pieces of large yellow croaker were individually immunized with 50 μg of the recombinant protein by intraperitoneal injection.Four weeks after vaccination,ten pieces were artificially challenged by intraperitoneal injection with live bacteria and the mortality was recorded in the following 14 d.Relative percentage of the survival rate of the immunized group reached 85%.Specific antibody level was detected by indirect ELISA after 4-8 weeks post vaccination.Resulting an increase of antibody titers to the immunized recombinant protein.The present study demonstrated strong immunogenicity of the recombinant OmpU.OmpU of V.harveyi should be given enough attention for their potential application in vaccine development.
YU Yan-mei , WU Zhi-xin , CHEN Xiao-xuan , ZHAO Yang , ZHANG Peng , ZHOU Jin-min , YUE Gang-yi , WANG Shu-yun , QU Yi
2010, 29(3):351-355. DOI: 1000-2421(2010)03-0351-05
Abstract:This experiment was conducted on healthy Pelteobagrus fulvidraco to study the effects of mannan oligosaccharides on non-specific immune function and the growth.The experimental fishes were divided into five groups.There are three replicates for each group.The control group(C) contained no mannan oligosaccharides,the treatment groups(KM0.1,KM0.2,KM0.3,M0.3) were contained 0.1%,0.2%,0.3% of konjac mannan oligosaccharides(Kon-Mos) and 0.3% of yeast cell wall mannan oligosaccharides,respectively.The results showed that:between 14 and 28 day,the phagocytic activity of leukocytes in group KM0.2 were significantly higher than the control group(P<0.05),phagocytic percentage and phagocytic index reached to the top level on the 14 d,66.00%,5.24,respectively.The phagocytic activity of leukocytes in group KM0.3,M0.3 were not significantly higher than the control group(P>0.05).The lysozyme activity,blood serum superoxide dismutase activity in group KM0.2 were significantly higher than the control group(P<0.05),LSZ reached to the top level on the 35th day,SOD reached to the top level on the 7th day,0.31,136.67,respectively.The blood serum superoxide dismutase activity in group KM0.3,M0.3 were not significantly higher than the control group.Fish fed diets with Kon-Mos supplementation had significantly higer viscera index,growth rate and lower feed conversion ratio.The growth rate of group KM0.2 was the highest(95.68%),and feed conversion ratio was the lowest(1.63).The group M0.3 had significantly higher growth rate and lower feed conversion ratio than the control group,64.91%,1.84,respectively.
ZHONG Wei-wei , WEN Hua , JIANG Ming , WU Fan , YUAN Dan-ning , LIU Tai-liang , LIU Wei
2010, 29(3):356-362. DOI: 1000-2421(2010)03-0356-07
Abstract:A study with increasing levels of a plant protein mixture(PM) replacing fish meal (FM) in diets for juvenile Nile tilapia,was conducted to elucidate effects on its growth performance,body conposition and digestibility.The PM was consisted of 25% cottonseed meal,25% rapeseed meal,25% corn gulten meal and 25% broad bean.Five isonitrogenous (crude protein 30%) and isoenergetic (20 kJ/g) diets replacing 0%(control),25%(PM25),50%(PM50),75%(PM75) and 100%(PM100) of the FM with PM were formulated.Each experimental diet was fed to triplicate groups with 30 Nile tilapia juveniles (initial body weight 7.16±0.81 g) in 400 L aquaria for 10 weeks.The water temperature was 21±0.5℃,and dissolved oxygen was approximately 5.0 mg/L during the experimental period.The results showed that weight gain rate(WGR),specific growth rate(SGR),feed conversion ratio(FCR) and protein efficiency ratio(PER) of fish fed with diets PM25,PM50,PM75 were not significantly different from those of fish fed with control diet,while fish fed with PM100 had significant difference with those of fish fed with the other diets.No significant differences in HSI and VSI were observed among dietary treaments.The whole body proximate analysis showed that protein and ash contents significantly decreased with increasing dietary PM levels,while the whole body lipid content increased.Except hisidine content was increased with increasing dietary PM levels,there were no significant effects on muscle indispensable amino acid (IAA) and total amino acid contents.Taste amino acid to total amino acid ratio decreased with increasing dietary PM levels,and no effect on total amino acid content was observed.PM substitution up to 75% of the FM protein did not result in differences in the apparent digestibility of protein and total amino acid compared with the control,whereas in the PM100 group digestibility was significantly lower than the other groups; no significant effects were found on lipid digestibility.These results suggest that 75% FM replacement by PM caused no significant effect on the growth,body composition and digestibility of Nile tilapia.
HU Wei-juan , ZHANG Qi-xiang , PAN Hui-tang , DONG Ling-ling
2010, 29(3):363-368. DOI: 1000-2421(2010)03-0363-06
Abstract:The index of heat injury and leaf anatomical structure under the scanning electron microscope of six Primula species were measured to study the responsive mechanism of Primula to the high temperature and to select the heatresistant Primula species.The results showed that Primula forrestii and P.malacoides franch had higher heat-resistance than that of P.obconica,P.veris,P.saxatilis,P.denticulatess.,P.sinodenticulata with lowest heat-resistance.Leaf anatomical structures of Primula associated with heat-resistance included leaf thickness,tightness of mesophyll cell arrangement,the number of open stomata,the number of epidermal hair and powders of leaves.
WANG Rui , DING Ai-ping , DU Lin-feng , ZHANG Zhuo-wen
2010, 29(3):369-374. DOI: 1000-2421(2010)03-0369-06
Abstract:Twelve species of shade plant were used to study the photosynthetic characteristics under sun-shading conditions.The net photosynthetic rate change,average net photosynthetic rate,apparent quantum yield and light compensation point was investigated under different sunshading conditions.The results showed that the photosynthetic characteristics changed under different shading treatments.When the sun light was weak,the net photosynthetic rate varied from a two-peak curve to a single-peak one,which only happened under a certain sun-shading degree.With the increase of sun-shading degree,the daily average net photosynthetic rate and the apparent quantum yield increased to a peak,and then fell down while the light compensation point decreased continuously.There were extremely significant differences for each index of photosynthetic characteristics among 12 species of shade plant under different sun-shading treatments.Proper sun-shading is beneficial to the growth of shade plant and improvement of photosynthetic characteristics.
YAN Yu-juan , ZHAO Hu , YANG Qian , XIE Bi-xia
2010, 29(3):375-380. DOI: 1000-2421(2010)03-0375-06
Abstract:Based on sample plots,Phyllostachys pubescens community characteristics inYangmingshan National Forest Park were analyzed.Results showed that there are four community types,pure Phyllostachys pubescens forest,Castanopsis eyrei+Phyllostachys pubescens forest,Phyllostachys pubescens+Pinus massoniana forest and Phyllostachys pubescens+Taxus chinensis var mairei forest.Pure Phyllostachys pubescens forest is the largest in area.There are 46 species,belonging to 41 genera,26 families,8 geographical distribution types.Ratio of temperate genera (51.2%) is slightly higher than that of the tropical (48.8%).The community structure is relatively simple,Phyllostachys pubescens is the single dominant species.The lifeform of Phyllostachys pubescens community is composed of phaenerophytes,and leaves are mainly mesophyll,simple,coriaceous,entire leaf.Different Phyllostachys pubescens community types have different richness index,diversity index and average spaces between trees.Results of analysis on the level of diameter and age showed that Phyllostachys pubescens community in Yangming Mountain is declined.
RUAN Xiao-lei , HOU Yan , LI Hua-ping
2010, 29(3):381-386. DOI: 1000-2421(2010)03-0381-06
Abstract:Some indexes of food safety of transgenic papaya with the replicase gene of papaya ringspot virus(PRSV) were evaluated in this thesis.By means of biological informatics,the analysis between the sequence transformed to papaya and the allergen sequences from GenBank,EMBL databases,PIR databases,etc. indicated there were not continuously eight same amino acids compared to the eight classes of allergens,including peanut,soybean,nut,milk,egg,fish,shellfish and wheat.It could be inferred that the rep sequence transformed to papaya did not contain the known allergens. The fulllength rep gene of papaya ringspot virus was cloned into expression vector pET-28b(+) and the specific expression product was purified by Ni-NTA resin. Some protein were attempted to be renatured.Through imitated gastric juice and intestinal juice experiment, it had been further proved the protein product of Rep gene could be degraded in human beings’ digestive system,it was unlikely to cause to the human body to be allergic. From the transgenic and no-transgenic papaya,an endogenous poisonous substance called benzyl isothiocyanate(BITC)was respectively extracted by liquid phase extraction,concentrated and sent to China National Analytical Center,Guangzhou. The results of gas chromatography and biological statistical analysis showed that there was no distinct difference in transgenic and no-transgenic papaya.
SHEN Feng , YANG Li-li , XIONG Shan-bai , ZHAO Si-ming
2010, 29(3):387-391. DOI: 1000-2421(2010)03-0387-05
Abstract:The collagen peptide were prepared from scales of grass carp with pepsin,protamex,papain and alcalase.The effects of protease types and hydrolyzing conditions on the hydrolyzing degree,nitrogen recovery and gel strength of the hydrolysates were investigated.To obtain high gel strength collagen peptide,conditions for hydrolyzing were optimized with orthogonal experiment.The results showed that the nitrogen recovery of pepsin hydrolysate was much high,and the hydrolysate had the ability to form gel at low temperature.The results of orthogonal experiment indicated that hydrolyzing conditions had a significant effect on the hydrolyzing degree,nitrogen recovery and gel strength.To obtain higher gel strength and nitrogen recovery,the optimum value for substrate concentration,pepsin dosage,initial pH value and hydrolyzing temperature were 5.0%,4.0,140.0 U/g,and 65 ℃,respectively.The hydrolyzing degree of scales of grass carp by pepsin was 1.46%,with nitrogen recovery of 64.38%,gel strength of 2 051 g when hydrolyzing 120 minutes.
LUO Mei , WANG Lin , BIN Shu-ying , LIN Jin-tian
2010, 29(3):392-396. DOI: 1000-2421(2010)03-0392-05
Abstract:The cucumber green mottle mosaic virus(CGMMV) is one of the quarantine viruses in China which can seriously affect the product of watermelon, melon and cucumber. It has been found in Guangxi,Liaoning,Hebei,Shandong,Guangdong Province and Beijing in China presently. Thus it is important to establish effective methods for the detection of CGMMV. Biology method,serology method,molecular biology method and electron microscopy method are widely used in the detection of CGMMV. This paper made a comprehensive study on the above mentioned methods and pointed out the advantages and disadvantages of these methods as well as the new development of the detection of this virus.
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