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10 March 2008, Volume 22 Issue 2 Previous Issue    Next Issue
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研究报告
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Establishment of Technique for Plasma Membrane Proteomics from Rice Root Tips QI Yao-cheng ,WANG Ning ,CHENG Yan-wei ,XU Lang-lai ,ZHANG Wei 2008, 22(2): 111-117 .  Abstract ( )   PDF (2765KB) ( )   A highly purified plasma membrane fraction was isolated from rice root tips using an aqueous two-polymer phase-partition system,and the proteins in the fraction were solubilized by optimized rehydration buffer.Solubilized plasma membrane fraction was then separated with two dimensional gel electrophoresis.Among the result,31 membrane-associated proteins,visualized clearly,were analyzed by matrix assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF/TOF) mass spectrum.It indicated that isoelectric focusing/sodium dodecyl sulfate polyacrylamide gel electrophoresis(IEF/SDS-PAGE) was fit for the separation of hydrophilic peripheral proteins of the plasma membrane.In order to reduce the complexity of the fraction,high-salt solutions and gentle detergents had been used.According to the result of the SDS-PAGE and nanoelectrospray ionization tandem mass spectrometry(ESI-MS/MS),eight integral proteins which contained several transmembrane domains had been identified.It suggested that the complexity of the purified membrane was reduced.Each strip of the SDS-PAGE contained one or two proteins.Taken together,the integration of various separation methods and different mass spectrums analysis would be the validity means for the plasma membrane proteomics.The optimization of the membrane proteomics method paved the way for the comparative proteomic analysis of rice plasma membrane under stresses.

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Prokaryotic Expression,Purification and Characterization of a Novel Rice Seed Lipoxygenase Gene OsLOX1 WANG Ren ,SHEN Wen-biao ,JIANG Ling ,LIU Ling-long ,ZHAI Hu-qu ,WAN Jian-min 2008, 22(2): 118-124 .  Abstract ( )   PDF (3517KB) ( )   Lipoxygenase(LOX,EC 1.13.11.12) is a key enzyme during the degradation of lipids in animals and even plants.It is also the first key enzyme responsible for the biosynthesis of jasmonate.In this paper,the expression,purification and characterization ofOsLOX1 were reported.The entire coding region of theOsLOX1 gene was inserted into an expression vector pET30a(+) and transformed into Escherichia coli: BL21(DE3).The fusion protein was successfully expressed induced by IPTG and the purified recombinant protein was obtained with His·Bind○R Kits.Further assay showed that the purified recombinant protein exhibited the LOX activity.The optimum pH and temperature of above enzyme were 4.8(acetate buffer) and 30℃,respectively.Thus,this recombinant might confer an available usage for the synthesis of jasmonate in vitro,and also provide a possibility for elucidating the inter-relationship between the primary structure of the plant seed lipoxygenase protein and its physiological functions.

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Mapping and Genetic Analysis of a Lipase Gene for indica Rice GONG Ji-ping ,WU Fang-xi ,WU Yue-jin ,ZHENG Jia-tuan ,HUANG Ting-xu ,WANG Wu-qi ,ZHANG Jian-fu ,XIE Hua-an 2008, 22(2): 125-130 .  Abstract ( )   PDF (221KB) ( )   The quantitative and genetic analyses of lipase activity in rice embryos were conducted using two indica rice materials PT46(containing high lipase activity in its embryos),and WP20(containing low lipase activity in its embryos) and their F2 population.It was found that the distribution of F2 phenotype fitted 1∶2∶1 Mendelian rule based on χ2 test of their lipase activity in rice embryos.This indicated that the activity of lipase in embryos was controlled by a single resessive gene.Moreover,the gene for lipase activity,temporarily designated as la(lipase activity) was mapped on the chromosome 3 of rice by bulk-segregation analysis of F2 population between PT46 and WP20,with the distances of 14.8 cM and 4.1 cM to SSR marker RM7 and RM232,respectively.Storability of two parents and their F2 population were evaluated with their grermination rate and aging index in artificial accelerated aging experiments.Correlation analysis showed that the seed germination rate of high lipase activity materials was decreased rapidly and the aging index was raised quickly with the increasing treatment time,whereas the aging index of low lipase activity materials was increased slowly,namely,the low lipase activity materials had better storability.After 10 and 20 days of artificial accelerated aging,the correlation coefficients were 0.6165 and 0.4703 between the lipase activity and aging index,respectively,suggesting that there existed a stable positive correlation between the aging index and the lipase activity.

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Analysis on T4 Progeny of Transgenic Rice with Lysine-Rich Protein Gene (sb401) Mediated by Agrobacterium tumefaciens Transformation LI Ke ,WANG Shi-quan ,WU Fa-qiang ,LI Shuang-cheng ,DENG Qi-ming ,WANG Ling-xia ,LIANG Yue-yang ,LI Ping 2008, 22(2): 131-136 .  Abstract ( )   PDF (952KB) ( )   The lysine-rich protein gene sb401 had been successfully introduced into a japonica rice variety Nipponbare by Agrobacterium-mediated transformation.Out of ten independent transformed lines,nine homozygous T4 generation transgenic lines were obtained through consecutive selfing.Southern blotting analysis of T4 lines showed that the integration sites of the foreign gene were random with low copy numbers(1 to 3).TAIL-PCR analysis showed that eight T-DNA flanking sequences were located on seven chromosomes.Detection of protein and amino acids contents of T4 lines showed thatsb401 gene contributed,to some extent,to the increase of lysine and other amino acids contents in transgenic lines.The analysis combining blotting and T-DNA position showed that the expression difference was not obvious when there were low copies in transgenic rice lines.

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Dissection of QTLs for Plant Height and Yield Traits on the Short Arm of Chromosome 6 in Rice ZHAN Xiao-deng ,FAN Ye-yang ,CHENG Shi-hua ,ZHUANG Jie-yun ,CAO Li-yong 2008, 22(2): 137-142 .  Abstract ( )   PDF (2362KB) ( )   A residual heterozygous line carrying heterozygous segments covering an interval RM587-RM19715 on the short arm of chromosome 6 in rice was selected from a recombinant inbred line population of Zhenshan 97B/Milyang 46.The resultant F2 population was used to detect quantitative trait loci(QTLs) on the short arm of rice chromosome 6 that control yield traits and plant height.Two clusters of QTLs were detected and located on the top and bottom intervals of the target region.Each cluster showed significant effects for all the yield components except for the number of panicles per plant.One QTL cluster for yield traits in the two clusters were dissected and the QTLs were defined into narrowing regions,thus providing available conditions for QTL fine mapping and cloning.

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Mapping and Dissection of QTLs for Grain Weight per Panicle and 1000-Grain Weight in Rice WU Jia-sheng ,ZHOU Hong-kai ,CHEN Guo-bo ,LIU Gui-fu 2008, 22(2): 143-147 .  Abstract ( )   PDF (1779KB) ( )   The grain weight per panicle(GW) and 1000-grain weight(TGW) of rice were investigated on 129 doubled haploid(DH) lines grew in two different seasons.The mixed-model based on composite interval mapping approach(MCIM) was used to detect QTLs.There were 15 QTLs detected underlying each trait.Among them,6 QTLs were responsible for simultaneous expression of the two traits.All QTLs detected were located in the marker intervals of the other 10 chromosomes apart from chromosomes 11 and 12.Of all QTLs for TGW,12 were detected with additive effects(a) and six pairs with additive × additive interaction effects(aa),and these QTLs hardly interacted with environment.Out of all QTLs for GW,seven were detected with a,of which four were environment-dependent,and six pairs with aa,of which one pair was sensitive to changes in environment.The estimated additive effect ofqTGW2 was 1.149 g,with a contribution of more than 10% to TGW.The additive effect of each QTL(qGW1, qGW7 and qGW8-1) had a contribution of more than 10% to GW when expressed in early season.

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Developmental Genetic Analysis for Plant Height in indica Hybrid Rice Across Environments PENG Tao,ZHONG Bing-qiang,LING Ying-hua,YANG Zheng-lin,ZHA Ren-ming,XIE Rong,LIU Cheng-yuan,HE Guang-hua 2008, 22(2): 148-154 .  Abstract ( )   PDF (2330KB) ( )   The developmental genetic rule of plant height was analyzed from two groups of three-line indica hybrid rice at two environmental conditions based on the NCⅡ design, using the additive-dominant developmental genetic models and the statistic methods. The results showed that the materials and environmental conditions both could affect plant height, and the effects of environment on plant height were decreased gradually with plant development. Additive and dominant effects both governed the performance of plant height at all developmental stages. However, the degree of effect varied with materials. Moreover, the interaction between environmental effects and genotypes also affected plant height. The genetic effects differed at most developmental stages. Furthermore the expression of additive effect was more active than that of dominant effect. Conditional interaction effects with environment also had some effects on plant height during genetic development, especially at the early stages. Mid-parent heterosis (HMP) increased gradually with the developments stage of plant height, and maximized at the latest stage, whereas, heterosis over the better parent (H BP) showed differences among the materials, and kept stable at the later stage, with positive numeric value. At most developmental stages, conditional HMP was positively significant, while conditional HBP was negatively significant. All above results showed that HMP and HBP had some new expression in all developmental periods and level and direction were quite different.

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Effect of Free Air CO2 Enrichment (FACE) and Nitrogen Level on Endopeptidase Activities in Rice Leaves During Grain Filling Stage HU Jian ,YANG Lian-xin ,ZHOU Juan ,WANG Yu-long ,ZHU Jian-guo 2008, 22(2): 155-160 .  Abstract ( )   PDF (46KB) ( )   A japonica rice variety Wuxiangjing 14 was grown under ambient(AMB) or elevated CO2(FACE,AMB + 200 μmol/mol) conitions and supplied with three levels of nitrogen: low level(LN,15 g/m2),normal level(NN,25 g /m2,similar to the level recommended to local farmers) and high level(HN,35 g/m2) to investigate the effect of elevated CO2 and N supply on endopeptidase(EP) activity and the specific activity in the flag and the second leaves from the top of rice.As compared with AMB,FACE significantly increased EP activity in the flag and the second leaves at 10 days after heading(DAH) and 20 DAH,as well as EP activity in the second leaves at heading.However,EP activity in the flag leaves at maturity was greatly reduced under FACE.FACE obviously increased the specific activity in the flag and the second leaves at 10,20 DAH and maturity,together with the specific activity in the second leaves at heading.In general,CO2 enrichment-induced changes in both EP activity and specific activity were larger at 10 and 20 DAH than at heading and maturity.EP activity at early filling stage decreased greatly with increasing N supply,while it showed adverse trends at late filling stages.The specific activity decreased with increasing N supply at all sampling stages,with CO2 enrichment-induced decreases being larger at early than at late filling stages.Compared with AMB,FACE significantly decreased the content of soluble protein in the flag and the second leaves at 10,20 DAH and maturity,and CO2 enrichment-induced changes in the content of soluble protein significantly decreased with increasing N supply.Soluble protein contents were correlated positively with EP activity in the flag and the second leaves at the maturity stage,while it showed adverse trends at the other sampling stages.This suggested that the CO2 enrichment-induced reduction in soluble protein content in leaves at the filling stage closely linked with corresponding changes in EP activity at elevated CO2.

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Coupling Effects of Soil Moisture and Nitrogen Nutrient During Grain Filling on Grain Yield and Quality of Rice LI Guo-sheng ,WANG Zhi-qin ,YUAN Li-min ,LIU Li-jun ,YANG Jian-chang 2008, 22(2): 161-166 .  Abstract ( )   PDF (37KB) ( )   An indica hybrid rice combination Shanyou 63 and a japonica variety Wuyujing 3 were grown in tanks.Three nitrogen(N) levels,0N(0g/m2),NN(normal level of N,4.5g/m2) and HN(high level of N,9.0g/m2),were applied at the beginning of heading,and three soil moisture treatments,WW(well-watered),MD(moderate soil drying,soil water potential at-25kPa) and SD(severe soil drying,soil water potential at-50kPa),were conducted from 7d after heading to maturity.The coupling effects of soil moisture and nitrogen nutrient on rice quality were investigated.The results showed that grain yield,brown rice rate,milled rice rate and head rice rate were the greatest,while chalky grain rate and chalkiness were the lowest,under the MD treatment,irrespective of the N level.The SD treatment significantly reduced grain yield and degraded the milling quality,appearance quality,and eating quality at the 0N level.The differences in grain yield,milling quality,appearance quality and eating quality between SD and WW were not significant at MN and HN levels.This suggests that the interaction between soil moisture and N level affects grain yield and quality of rice,and that soil water potential at-25kPa during grain filling and the N rate at 45kg/hm2 applied at the beginning of heading benefit the formation of high-yielding and good quality.

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Comparison on Milling Quality of Grains at Different Positions Between Erect Panicle and Curved Panicle Varieties in Rice JIN Feng ,CHEN Shu-qiang ,XU Zheng-jin ,YUAN Ying ,LI Pei-pei 2008, 22(2): 167-174 .  Abstract ( )   PDF (176KB) ( )   Differences in milling quality among the grains at different positions and different grains between the erect and curved panicle types were studied.The results showed that the rates of brown rice,milled rice and head rice and the grain weight of the curved-panicle type rice were higher than those of erect-panicle type rice,of which the difference in head rice rate reached significant level.Generally,at the same positions of a panicle,the brown rice rate,milled rice rate,head rice rate and the weight of the grains on the primary branches were greater than those on the secondary branches in both of the two types.On the primary branch,the rates of brown rice,milled rice and head rice of the first grain were the least and those of the second or the third grain was the greatest.The difference in the milling quality of the grains on the secondary branches at the same parts between the two panicle types was greater than that on the primary branches regardless of panicle type.The distribution of grain weight on the panicles was consistent in the two panicle types.Therefore,the milling quality of erect-panicle rice could be improved through selection in rice breeding.

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Plant Temperature and Its Simulation Model of Thermo-Sensitive Genic Male Sterile Rice LU Chuan-gen ,XIA Shi-jian ,HU Ning ,YAO Ke-min 2008, 22(2): 175-182 .  Abstract ( )   PDF (3317KB) ( )   Plant temperature and its relations to the micro-climate of rice canopy and the factors of irrigation water were studied under irrigation treatment(10-15 cm water layer) and CK(no water layer) using a thermo-sensitive genic male sterile(TGMS) rice,Pei′ai 64S as material.There were both value and phasic differences between the rice plant temperature and air temperature at 150 cm height.From 8:00 to 20:00,the plant temperature was lower than air temperature,whereas was close during 21:00 to next 7:00.The maximum of plant temperature appeared one hour earlier than that of air temperature,whereas both reached the minimum at 6:00.The fluctuation of plant temperature was lower than that of air temperature.At a certain height,during 6:00-13:00,the plant temperature was higher,and one hour earlier reached the maximum compared with air temperature,however,during the other time,the plant temperature was close or even a little lower than air temperature under sunny days.Contrastively,on overcast days,the plant temperature was higher than air temperature in all day,and both maximized at the same time.Plant temperature was controlled by solar radiation,and modified by cloudage and wind in the daytime.Moreover,plant temperature was mainly affected by irrigation water at night.In the present experiment,air temperature(Ta) of 29.6℃ was the critical point.WhenTa>29.6℃,irrigation water would decrease plant temperature,otherwise increase.The plant temperature and the temperature difference of water-air showed a conic relation.Rice leaf absorbs or reflects solar radiation during daytime,and countercheck the loss of heat during night time,thereby mitigating plant temperature fluctuation.By correlation analysis and coefficient simulation,two effective practical models of plant temperature were established.

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Relationship Between Resistance Gene Analogue and Blast Resistance in Rice CHEN Yu-min ,FAN Cheng-ming ,YANG Yan ,HE Yue-qiu 2008, 22(2): 183-189 .  Abstract ( )   PDF (4343KB) ( )   DNA fragments of 43 rice varieties were amplified with 11 pairs of primers designed based on resistance gene analogue(RGA) of plants and blast resistance of the varieties was identified by inoculation with 33 isolates collected from Yunnan Province,China.Clustering results revealed significant correlation between the resistance and DNA bands with a correlation coefficient of 0.6117(α=0.01),indicating that the resistance analysis based on RGA-PCR bands was coincided with that based on inoculation.However,the correlation coefficient,ranged from 0.1701 to 0.5305 depending on the primers.The 5 pairs of primers,S1/AS3,S1 INV/S2 INV,XLRR For/XLRR Rev,Pto-Kin 1 IN/Pto-Kin 2 IN,NLRR For/NLRR Rev could be applied to blast resistance identification under consideration of their band numbers and polymorphism.Besides,the 11 pairs of primers could classify indica and japonica rice very well except two highly susceptible varieties,CO39 and Lijiangxintuanheigu.

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Evaluation on Resistance of Major Rice Blast Resistance Genes to Magnaporthe grisea Isolates Collected from indica Rice in Guangdong Province,China YANG Jian-yuan ,CHEN Shen ,ZENG Lie-xian ,LI Yi-long ,CHEN Zhen ,ZHU Xiao-yuan 2008, 22(2): 190-196 .  Abstract ( )   PDF (466KB) ( )   Race specific resistance and field resistance of 30 monogenic rice lines resistant to rice blast,derived from different resources were evaluated.The resistance spectrum(RS) of the tested monogenic lines ranged from 0.6% to 89.6%.Most of the monogenic lines showed narrow RS and high susceptibility in the blast zone,but the lines with Pikh and Pi1(t) showed good and stable blast resistance in field with the RSs of 89.6% and 82.2%,respectively.According to the cluster analysis of specific resistance to 163 blast isolates collected from indica rice in Guangdong Province,China,the 30 monogenic lines were divided into 15 groups,and based on the principal component analysis,9 kinds of race-specific resistance were identified.Pik,Piz5,Pi9,Pish could be used as candidate resistance genes for future rice breeding since their specific resistance differed from those of the key parents in Guangdong.Pyramiding of Pikh[or Pi1(t)],Pi9(or Piz5) and Pish(or Pita2) will be an effective measure to obtain broad spectrum blast resistance in local rice breeding program.The strategy for studying rice blast resistance genes and its application was discussed.

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Monitoring of Resistance to Buprofezin in Brown Planthopper,Nilaparvata lugens(Homoptera: Delphacidae) LI Wen-hong ,GAO Cong-fen ,WANG Yan-hua ,ZHUANG Yong-lin ,DAI De-jiang ,SHEN Jin-liang 2008, 22(2): 197-202 .  Abstract ( )   PDF (366KB) ( )   Rice stem-dipping method was used to monitor the susceptibility ofNilaparvata lugens(St°al) to buprofezin in 27 field populations,which were collected from eight provinces(region) in China from 1996 to 2007.The results showed that the populations from Jiangsu Province [Jiangpu(JPZY),Yizheng(YZZY) and Nantong(NTZY)],Anhui Province(Anqing,AQNS),and Guangxi [Nanning(GXNY) and Guilin(GLNS)] were very susceptible to buprofezin from 1996 to 2002,with resistance ratios of 0.3-to 3.5-fold.However,the populations of Jiangsu Province [Jiangpu(JPZY),2005] and Hainan Province [Lingshui(HNLS),2007] had developed a moderate level of resistance to buprofezin(28.8-and 19.4-fold,respectively);the populations from Guangxi [Nanning(GXNY) and Guilin(GLNS)],Hunan Province [Changde(CDTY)],Jiangxi Province [Xinjian(XJSM)],Zhejiang Province [Yuyao(YYLJ)],Anhui Province [Hexian(HXLY) and Qianshan(QSMC)],and Jiangsu Province [Nantong(NTZY)] showed a low level of resistance(5.6-to 9.1-fold) from 2005 to 2007;and the populations from Jiangxi Province [Shanggao(SGMS)],Zhejiang Province [Lanxi(LXYC)] and Hubei Province [Xiaogan(XGXC)] in 2006 were susceptible to buprofezin(2.5-to 4.1-fold).TheN.lugens collected from Anhui Province [Anqing(AQNS)] in 1996 had been selected with buprofezin for 13 generations in intermission during 22 generations,resulting in a LC50 decrease of 30%,and there was no significant difference in susceptibility between post-and pre-selections.However,after successive selection for 15 generations,the resistance ratio ascended to 1157.7-fold,which showed thatN.lugens had the risk of developing a high level of resistance to buprofezin if this insecticide was applied successively and alone.The strategy of resistance management of N.lugens was also proposed.

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Rice Yield Loss Caused by Rice Stripe Disease and Economic Threshold WANG Hua-di ,CHEN Jian-ping ,ZHU Zeng-rong ,SUN Xiang-liang ,ZHU Jin-liang ,FU Qiang ,ZHU Li-Ming 2008, 22(2): 203-207 .  Abstract ( )   PDF (40KB) ( )   Rice stripe disease,transmitted by the rice small brown planthopperLaodelphax striatellus Fallén(Homoptera: Delphacidae),has been a severe devastating disease in Northern Zhejiang,China since 2004.To understand the relation of rice grain yield loss to the incidence of the disease and the density of the vector,a series of experiments were conducted from 2004 to 2006 in rice fields.The results showed that the incidence of the disease(Y1) at the seedling stage increased with the increasing density of infectious vector(X2) as the equation of Y1=0.0873 + 1.0757X2,while the rice yield loss(Y,%) increased positively in a linear mode with the incidence(X,%) in the single-cropping late rice asY=0.1254 + 0.7551X.The economic injury level(EIL) was calculated as 2.0%-2.5% of yield loss according to the current economic scenarios for rice production for the control of the disease.Therefore the economic threshold for controlling the disease was set as the density of 2-3 per square meter of the small brown planthopper in the seedling nursery and at the early stage in rice fields.Such economic threshold has been practically applied in control of the disease in large scale fields and a significant economic benefit has been achieved.

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Construction of Double Right-Border Binary Vector Carrying Non-Host Gene Rxo1 Resistant to Rice Bacterial Leaf Streak XU Mei-rong ,XIA Zhi-hui ,ZHAI Wen-xue ,XU Jian-long ,ZHOU Yong-li ,LI Zhi-kang 2008, 22(2): 208-210 .  Abstract ( )   PDF (1198KB) ( )   Rxo1 cloned from maize was a non-host gene resistant to bacterial leaf streak of rice.pCAMBIA1305-1 withRxo1 was digested withScaⅠandNgoM Ⅳ and the double right-border binary vector pMNDRBBin6 was digested withHpaⅠandXmaⅠ.pMNDRBBin6 carrying the geneRxo1 was acquired by ligation of blunt-end and cohesive end.The results of PCR,restriction digestion and sequencing showed that theRxo1 gene has been cloned into pMNDRBBin6.This double right-border binary vector,being named as pMNDRBBin6-Rxo1,would play a role in breeding marker-free plants resistant to rice bacterial leaf streak by genetic transformation.

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QTL Analysis of Lodging Resistance Force and Lodging Resistance-Related Traits in Rice HU Jiang ,Kan FUJIMOTO ,GUO Long-biao ,ZENG Da-li ,ZHANG Guang-heng ,DONG Guo-jun ,WANG Xiao-hu ,ZHU Li-huang ,QIAN Qian 2008, 22(2): 211-214 .  Abstract ( )   PDF (1268KB) ( )   A set of 127 doubled haploid(DH) lines derived from a cross between an indica parent Zhaiyeqing 8 and a japonica variety Jingxi 17 were used to investigate the traits related to lodging resistance such as the lodging resistance force,plant perimeter,plant height,panicle number per plant,gravity center height and aboveground fresh biomass.The quantitative trait loci(QTLs) were identified based on the molecular linkage map.Except for aboveground fresh biomass,a total of eight QTLs affecting other five traits were detected.One QTL each for lodging resistance force,plant perimeter and panicle number per plant was detected on chromosomes 8,8 and 12 with the explained variance of 18.4%,12.6% and 10.6%,respectively.Two QTLs for plant height were located on chromosomes 4 and 8 with the explained variance of 12.7% and 12.5%,respectively.Three QTLs related to gravity center height were on chromosomes 4,8 and 10 with the explained variance of 12.5%,14.6% and 10.0%,respectively.There were significant positive correlations between the lodging resistance force and plant perimeter,plant height,gravity center height and aboveground fresh biomass.

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Germination Dynamics of Weedy Rice in Northern China at Different Sowing Depths MA Dian-rong ,WANG Nan ,WANG Ying ,JIA De-tao ,CHEN Wen-fu 2008, 22(2): 215-218 .  Abstract ( )   PDF (649KB) ( )   A pot experiment was conducted to study the seedling emergence of weedy rice in Northern China at different sowing depths.Results showed that the elongation of mesocotyl and internode of coleoptile played important roles in the seedling emergence of the weedy rice from northern China.The mesocotyl of weedy rice elongated at 3 cm sowing depth,but both the mesocotyl and the coleptile elongated at 5 cm sowing depths.The germination dynamics of weedy rice at deep sowing depth depended on the elongation of mesocotyl and coleoptile.

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Rice Sheath Blight Pathogen (Rhizoctonia solani) Impacts the Activities of Disease Resistance-Related Enzymes in Leaves of Different Rice Varieties HUANG Shi-wen ,WANG Ling ,WANG Quan-yong ,TANG Shao-qing ,CHEN Hui-zhe ,E Zhi-guo ,WANG Lei ,ZHU De-feng 2008, 22(2): 219-222 .  Abstract ( )   PDF (35KB) ( )   Two indica rice varieties,ZH5 [high rice quality,resistant to sheath blight(ShB)(Rhizoctonia solani Kühn)],Teqing(resistant to ShB),a javanica rice variety Lemont(susceptible to ShB) and three restorer lines Luhui 17,Duoxi 1 and GB8 were used as materials forR.solani inoculation.The activities of disease resistance-related enzymes including superoxide dismutase(SOD),peroxidase(POD) and the content of malondialdehyde(MDA) in rice leaves were tested after the inoculation.The results indicated that the SOD activity in the rice leaves of ZH5 and Teqing were significantly higher than that of Lemont whether or not inoculated withR.solani.The POD activity in the resistant rice varieties increased but the susceptible one decreased after the inoculation withR.solani.The contents of MDA both in resistant and susceptible rice leaves increased after the inoculation.However,the MDA content in the leaves of ZH5 was significantly lower than that in the other tested rice materials.