Archive

10 July 2012, Volume 26 Issue 4 Previous Issue    Next Issue
---
Reviews and Special Topics
Research Papers
Experimental Techniques
Short Communications


For Selected:

Download Citations EndNote Ris BibTeX

Toggle Thumbnails

Reviews and Special Topics

Select

Regulatory Pathways of Rice Flowering in Different Light and Temperature Conditions SONG Yuanli, LUAN Weijiang* 2012, 26(4): 383-392.  DOI: 10.3969/j.issn.10017216.2012.04.001 Abstract ( )   PDF (642KB) ( )   The transition from vegetative growth to reproductive growth (the floral transition) is a crucial event in the life cycle of rice, which is regulated by both endogenous genes and environmental factors. Rice would not normally flower without  this transition. Light and temperature are two important environmental factors to regulate the floral transition in rice. Interestingly, how could rice perceive the change in photoperiod or temperature, and then initiate the expression of endogenous genes to control this transition? Scientists had contributed to answer this question for many years.With great progresses in rice flowering regulation recently, new evidences and understanding for the regulatory pathways of rice flowering have been provided. Based on previous studies and our results, the latest research progresses involving in molecular mechanisms of rice flowering are summarized and analyzed.

Select

Research Advances in the Effect of High Temperature on Rice and Its Mechanism DUAN Hua, YANG Jianchang* 2012, 26(4): 393-400.  DOI: 10.3969/j.issn.10017216.2012.04.002 Abstract ( )   PDF (551KB) ( )   With the continuous increase of the greenhouse and extreme weather effect, high temperature occurs more frequently. To understand the mechanism involved in the effect of high temperature on rice growth and to put forward countermeasures to reduce damage of the stress to rice would have great significance in promoting rice production and ensuring food security. This paper  reviewed the effects of high temperature on rice yield and grain quality and its physiological mechanism involved from the aspects of photosynthetic characteristics, stress resistance, proline, hormones, polyamines, enzymatic activities, and proteomics. The regulation techniques to reduce the harms of high temperature and issues for further studies were discussed.

Research Papers

Select

Identification and Studies of a Rice Mutant hya1 with Semidwarf and Aneuploid  Traits  GUO Tao, LIU Yongzhu, ZHANG Jianguo, CHEN Zhiqiang*, WANG Hui* 2012, 26(4): 401-408.  DOI: 10.3969/j.issn.10017216.2012.04.003 Abstract ( )   PDF (1047KB) ( )   A semidwarfing rice mutant hya1，  genetically  unstable  in plant height was obtained through  space mutagenesis of Texianzhan 13. Compared to the wild type, hya1 mutant was featured by  semidwarfness,   fewer  tillers, slim culms, reduced grain number  per panicle, low seed setting rate and low germination rate. Segregation of plant height in  selfed progenies of the mutant  was observed. Normal plants of selfed progenies, however, showed genetic stability. Plant height of F1 hybrid and F2 progenies generated from the cross  between hya1 mutant and Texianzhan 13 did not follow Mendelian inheritance. Furthermore, selfedprogenies of the  mutant  had  abnormal chromosome numbers (e.g. 2n=22, 23, 25 and 36 instead of 2n= 24). In addition, there were some pollen mother cells of hya1  with 11 bivalents at the diakinesis stage of meiosis. Realtime quantitative PCR analysis of normal and semidwarf plants from selfed progenies of  the mutant along with Texianzhan 13 showed equal copy number of chromosome in normal and wild type plants while the copy number of chromosome 8 and 11   differed in hya1and semidwarf plants from the selfed progenies. It    suggested  that hya1 mutant is a new aneuploid in which abnormal phenotype and genetic instability are caused by  abnormal chromosome number and/or varying copy number of certain chromosomes.

Select

New Stably Expressed Loci for Panicle Angle in japonica Rice in Four Environments NIU Fuan1,2, LIU Jian1, GUO Yuan1, CHEN Lan1, JIANG Jianhua1, HONG Delin1,* 2012, 26(4): 409-416.  DOI: 10.3969/j.issn.10017216.2012.04.004 Abstract ( )   PDF (2527KB) ( )   Panicle angle of the RIL population derived from a cross between two japonica varieties Xiushui 79 and C Bao was investigated in four growing environments. Genetic analysis was conducted by mixed major gene plus polygene inheritance models, and QTL identification was performed by QTLNetwork 2.0 and composite interval mapping approach of WinQTLcart 2.5 software in the RIL population. Results were as follow: 1) panicle angle was controlled by two major genes plus polygenes, mainly by major genes; 2) eight QTLs were detected by QTLNetwork 2.0 software, explaining 0.01%-39.89% phenotypic variation. 12 QTLs were detected by WinQTLcart 2.5 software, explaining 2.83%-30.60% phenotypic variation. All the QTLs detected above were located on chromosomes 4, 5, 6, 7, 9 and 11. Of which, two major QTLs (qPA9.2 and qPA9.5) at RM3700-RM3600 and RM5652-RM410 and qPA9.7 at RM257-OSR28 were all detected by the two methods in the four environments. The negative effect alleles of the three QTLs were contributed by Xiushui 79; 3) eight pairs of epistatic QTLs with few effects were also detected. QTL × environment interactions were not significant for additive QTLs and epistatic QTL pairs.

Select

Genetic Analysis of a QTL qPH3 for Plant Height in Rice LUO Ju#, SHAO Gaoneng#, WEI Xiangjin, CHEN Mingliang, TANG Shaoqing, JIAO Guiai, XIE Lihong, HU Peisong* 2012, 26(4): 417-422.  DOI: 10.3969/j.issn.10017216.2012.04.005 Abstract ( )   PDF (1436KB) ( )   A recombinant inbred population derived from the  cross between  a javonica（D50）and an indica（HB277）rice was used to investigate the genetic factors affecting plant height. Ａ total of six quantitative trait loci（QTLs）with significant additive effect were identified for the plant height, and they were located on chromosome 1, 2, 3, 4, 6 and 8. One QTL qPH3 can stably express and have significant additive effects in Hangzhou, Zhejiang Province  with the explained variance of 16.52% and Linshui, Hainan  Province with the explained variance of 16.60%. One residual heterozygous line(RHL) was selected from the RILs  and a RHLF2 population was constructed. The    major QTL qPH3 with the explained variance of 76.13% was detected with the RHLF2 population. By progeny tests,  qPH3  was  finally mapped within about 204 kb in the region RM16211-RM16237. These results will be helpful for fine mapping and mapbased cloning of this QTL.

Select

Association Analysis of Rice Cold Tolerance at Tillering Stage with SSR Markers in japonica Cultivars in Northeast China ZHANG Yanmei, ZOU Detang* 2012, 26(4): 423-430.  DOI: 10.3969/j.issn.10017216.2012.04.006 Abstract ( )   PDF (986KB) ( )   The cold tolerance of rice at the tillering stage was evaluated with 140 rice cultivars(lines) from Northeast China as materials and association analysis was conducted among 96 selected materials which differed in cold tolerance with 84 SSR markers. The experimental results showed: there were 20.0% of rice materials with better cold tolerance, 30.71% with intermediate cold tolerance and 49.28% with worse cold tolerance; Correlation analysis showed that rice cold tolerance at the tillering stage was significantly positively correlated with seed setting rate and single panicle weight. Rice cold tolerance at the tillering stage and growth duration were significantly negatively correlated; Eighteen markers associated with rice cold tolerance were detected through the association analysis, markers like RM214，RM445，RM506，RM106，RM215，RM182，RM270 and RM229 were mutual authentication with familybased linkage mapping. These markers can be used for selection of rice cold tolerance resources in Northeast China. Finally, a serial of elite alleles, loci and their carrier materials were screened out by anglicizing these associated markers.

Select

Indicajaponica Differentiation Degree and Genetic Diversity of japonica Cultivars Belonging to Different Ecotypes from the YangtzeHuaihe Region ZHOU Zhenling1,2 , WANG Baoxiang1, FAN Jiwei1, LU Baiguan1, ZHAO Zhigang2, JIANG Ling2, QIN Derong1, WAN Jianmin2,3, XU Dayong1,2,* 2012, 26(4): 431-437.  DOI: 10.3969/j.issn.10017216.2012.04.007 Abstract ( )   PDF (842KB) ( )   Indicajaponica differentiation degree of 81 japonica cultivars belonging to different ecotypes from JiangHuai Region were investigated by 25 specific SSR markers of indicajaponica differentiation. TDj values of the cultivars ranged from 0.773 to 0.962, indicating most of the cultivars had a high japonica component degree with the medium maturing midseason japonica(MMMj)  being the  highest and late japonica being the  lowest. In the 81 japonica cultivars, a total of 131 alleles were detected at 49 SSR loci, and allele number per marker ranged from 2 to 5, with an average of 2.67. Polymorphism information content(PIC) value of 49 SSR primer ranged from 0.068 to 0.657,with the average value 0.362. Among the 12 chromosomes，chromosome 11 showed the highest   average allele number and PIC value. Of the three different ecological type japonica cultivars, genetic diversity of the late maturing midseason japonica(LMMj)   was the highest according to PIC and  mean heterozygosity per locus(He). The coefficient of genetic similarity was the highest while the value of genetic distance was the lowest between MMMj  and LMMj, and the  coefficient of genetic similarity was the lowest while the value of genetic distance was the highest between MMMj  and late japonica. Clustering analysis with UPGMA method showed cultivars bred in the same breeding organization had a small  average genetic distance among cultivars.

Select

Effect Factor and Predict Model of Rice Quality Variation for MidSeason Hybrid Rice at Different Ecological Sites and Nitrogen Application Levels XU Fuxian, XIONG Hong, ZHANG Lin, GUO Xiaoyi, ZHU Yongchuan, ZHOU Xingbin, LIU Mao 2012, 26(4): 438-444.  DOI: 10.3969/j.issn.10017216.2012.04.008 Abstract ( )   PDF (418KB) ( )   Rice quality variation was analyzed with two midseason rice combinations at different ecological sites, basic fertility of soil and nitrogen application levels in 2009. The results indicated that the genotype was the most important factor followed by the ecological conditions, the basic fertility of soil and the nitrogen application level. The interaction between the genotype and the experiment site had a significant or highly significant effect on the amylose content, the gel consistency, the percentage of head milled rice, the percentage of chalky rice and the chalkiness. The gel consistency was significantly affected by the interaction between the genotype and the nitrogen application level, and the interaction between the experimental site and the nitrogen application level had a significant effect on the percentage of head milled rice. Suitable environment conditions such as high altitude, low longitude,high available N, high available K in soil for Ⅱ you 7, and high altitude, high available N, low organic fertilizer, low total P in soil for Yuxiangyou 203 contributed to improve rice quality. The predict models were established respectively between the amylose, the gel consistency, the percentage of head milled rice, the chalkiness, the ratio length to width and the geographical position, the basic fertility of soil, the nitrogen application level for Ⅱ you 7  and Yuxiangyou 203.

Select

Effect of Al2(SO4)3  Application on Fluorine Forms in Paddy Soil and Fluorine Absorption by Rice Plants LIU Jinhua, ZHAO Lanpo* , WANG Hongbin, ZHANG Zhidan, ZHANG Zhongqing 2012, 26(4): 445-450.  DOI: 10.3969/j.issn.10017216.2012.04.009 Abstract ( )   PDF (374KB) ( )   The variation of F content in rice plants and in paddy soil at different Al2(SO4)3 application levels was investigated in a biological pot experiment. The results showed that rice plants absorbed F extravagantly, and the order of F content in each part was as follows: husk＞brown rice ＞root＞straw. At a given   F level in soil, the concentration of F in each part was firstly decreased and then increased with rising Al2(SO4)3 application level. It minimized at 0.4% and 0.6% of Al2(SO4)3  levels, showing extremely significant difference with the blank control. As Al2(SO4)3 application level increased, the contents of free F and water soluble F were gradually decreased. The linear analysis showed that the two forms of F was negatively correlated with the amount of Al2(SO4)3 . But there was significant positive correlation between the content of residual F and Al2(SO4)3. The content of exchangeable F in soil   firstly increased   and then decreased with the increase of Al2(SO4)3 application amount and peaked at 0.2% Al2(SO4)3  level.  However, the exchangeable F content in soil at 0.2% Al2(SO4)3 level  was not significantly different from that of the control, and was extremely significantly differed with those at 04%-0.8% Al2(SO4)3 levels, indicating that Al2(SO4)3 mainly depressed the exchangeable F. The contents of complex F, Fe/Mn binding F and organic F were also firstly increased and then decreased with their maximum appeared at 0.4% and 06% Al2(SO4)3  levels. Correlation analysis showed that there was a significantly or extremely significantly negative correlation between the concentration of F in each part and the contents of Fe/Mn binding F, organic F in soil. Thus, at 0.4%-0.6% Al2(SO4)3 levels, equivalent to the F∶Al quality ration of 6∶1- 4∶3, the F concentration in each plant part was relatively lower, which indicated that its defluoridation efficiency was better. At the same time, the contents  of water soluble F, exchangeable F were lower and the contents of Fe/Mn binding F, organic F were higher which reduced F infiltration to groundwater and lower the F intake by people and animals  eating cooked rice and drinking groundwater.

Select

Population Characteristics of MachineTransplanted japonica Rice Based on Highyield Demonstration Fields YU Linhui1，2， LI Ganghua1， XU Jingjing1， LING Qihong1， DING Yanfeng1，* 2012, 26(4): 451-456.  DOI: 10.3969/j.issn.10017216.2012.04.010 Abstract ( )   PDF (445KB) ( )   The population characteristics, such as yield and its  components, accumulation of drymatter and nitrogen of machinetransplanted japonica rice was investigated in three highyield  demonstration fields(over 6.7 hm2 per field) at Zouqu, Caoqiao, and Qianhuang Towns, Wujin County, Jiangsu Province in 2008, and one  highyield demonstration field at Rudong County, Jiangsu Province in 2009. Results showed that yield was closely related with spikelet number per panicle and spikelet number per m2. The spikelet number per m2 should be greater than 45 000  as grain yield  was above 10.5 t/hm2. For highyield mechanically  transplanted rice (above 10.5 t/hm2), the dry matter accumulation from heading stage to maturity paid a contribution rate about 70%~80% to the grain dry weight. Nitrogen accumulation mainly occurred at the two growing stages, before critical tiller leaf age, and after heading. It indicated that higher spikelet number per m2 was the main basic characteristic of high yielding,  mechanically  transplanted japonica rice. And sufficient N supply, improved dry matter accumulation after heading, as well as spikelet number per panicle help increase grain yield of machinetransplanted japonica rice.

Select

Relationship Among Rice Planthoppers and Main Predatory Arthropods in RiceDuck Integrated Cultivation System QIN Zhong , ZHANG Jiaen* , ZHANG Jin , LUO Shiming 2012, 26(4): 457-466.  DOI: 10.3969/j.issn.10017216.2012.04.011 Abstract ( )   PDF (663KB) ( )   Based on the ecological niche theory, the population compositions and dynamics, time niche of planthoppers and main predatory arthropods were investigated in three experimental treatment plots: chemical fertilizer utilization plot, riceduck integrated cultivation plot and no chemical pesticides/fertilizer application plot, and grey relational grade analysis was conducted in the meanwhile. The results indicated that differences in individual numbers, temporal variation characteristics, temporal niche breadth and overlap index for rice planthoppers and the main predatory arthropods varied to various degrees among the three treatment plots. The number of rice planthoppers in its peak stage as well as the total individual number of the main predatory arthropods decreased. Compared with the chemical fertilizer utilization plot and the control plot, the ratio of natural enemy to rice planthoppers in the riceduck integrated cultivation plot decreased by 1.72% and 26.14%， respectively. Ecological niche breadths for predatory arthropods except Coccinellidae in the riceduck integrated cultivation plot were 2.14%-35.77% lower than those in the chemical fertilizer utilization plot, niche overlap indexes for most of the predatory arthropods, for instance, Tetragnathidae and Staphylinid, Araneidae and Coccinellidae increased concurrently. However, the number of the rice planthopper in the riceduck integrated cultivation plot were 23.70% lower than that in the chemical fertilizer utilization plot, owing to the greater effects of synchronization following performance and the enhanced pest controlling potentialities of Coccinellidae and Theridiidae, which were somewhat mitigated the influences caused by the reduction in the number of predatory arthropods and the weakened rice planthopper control capability. Grey correlation degrees between the main predatory arthropods and the rice planthopper in different rice cropping patterns or groups of predatory arthropods were differentiated. Coccinellidae, Lycosidae and Theridiidae had greater influences on rice planthopper in the riceduck integrated cultivation plot.

Select

Assessment on Potential Weediness of Transgenic Glufosinateresistant Rice Minghui 86B CUI Rongrong, WEI Ying, MENG Panpan, MA Yunlong, JIN Yuan, LI Qiuran, QIANG Sheng, DAI Weimin, SONG Xiaoling* 2012, 26(4): 467-475.  DOI: 10.3969/j.issn.10017216.2012.04.012 Abstract ( )   PDF (5012KB) ( )   To evaluate potential environment safety for release of transgenic rice  Minghui 86B, the potential ecological risk of weediness of transgenic glufosinateresistant rice Minghui 86B was assessed. The surviving and reproduction ability，seed shattering, seed viability of transgenic glufosinateresistant rice Minghui 86B, Minghui 86 and hybrid rice Shanyou 63 were comparatively evaluated in field, as well as their tolerance to flucetosulfuron in greenhouse. The surviving   and reproducing abilities of Minghui 86B and Minghui 86 were lower than that of  Shanyou 63 both in the appropriate season and in the unfavorable season, especially in the latter. The surviving ability of Minghui 86B was lower than that of Minghui 86. The seed shattering of the three rice materials were weak, and no volunteer seedlings were found. After shallow and deep buried, the seed viability of transgenic rice was weaker than those of Shanyou 63 and Minghui 86. The tolerance of the three rice materials to herbicides flucetosulfuron was similar. It is concluded that potential weediness of the transgenic glufosinateresistant rice Minghui 86B, was low in Nanjing, China.

Select

Silencing of OsDUF500 Gene in Rice Enhances Resistance to Xanthomonas oryzae pv. oryzae LI Juan, CHANG Shanshan, LIU Fengquan, SHAO Min* 2012, 26(4): 476-480.  DOI: 10.3969/j.issn.10017216.2012.04.013 Abstract ( )   PDF (857KB) ( )   Conserved functional region of DUF500 was cloned by PCR from cDNA of expression HarpinXoo (hrf1) transgenic rice NJH12. OsDUF500 encodes an unknown function member of DUF500 family. Calli from mature embryos of rice cultivar R109 were transformed by Agrobacterium tumefaciens strain EHA105/ABD::pVec8. There were eight OsDUF500 transgenic lines from nine hygromycin resistant lines by PCR analysis. Compared with the wild type, the downexpressed lines ABD are characterized by reduced plant height, shortened leaf and white blighted grain. Disease assays of transgenic rice plants infected by Xanthomonas oryzae pv. oryzae (PXO99) indicated that different transgenic lines had different resistance to rice leaf blight. Lesion length of the downexpression lines reduced significantly and lesion area all bellowed 30%. Lesion areas of the ABD3 and ABD5 were 12.3% and 15.7%, respectively. Thus, we predicted OsDUF500gene, which was upregulated in rice blast, maybe was a negative regulator on bacterial blight resistance.

Select

Characteristics of Overwintering Populations of Rice Stem Borers and Mutation Frequencies of Resistance to Triazophos LUO Guanghua1 , ZHANG Zhichun1 , HAN Guangjie1 , HAN Zhaojun2 , FANG Jichao1, * 2012, 26(4): 481-486.  DOI: 10.3969/j.issn.10017216.2012.04.014 Abstract ( )   PDF (380KB) ( )   Population structure and individual body weight of overwintering populations of Chilo suppressalis collected at 20 locations in China from September 2010 to February 2011 were compared. And the mutations associated with resistance to triazophos, an organophosphate insecticide, among these populations was also analysed by restriction fragment length polymorphism PCR (RFLPPCR). Results showed that the 6th instar larva was the predominant in 18 of 20 populations, and the composition of the overwintering populations didn′t vary with geographic locations, with the 4th, 5th or 6th instar larvae accounting for more than 90 percents of the overwintering individuals. Besides that, results also showed that the mutation frequencies associated with triazophos resistance differed among geographical populations, which closely related with the occurrence of the pest. In regions where C. suppressalis occurred frequently and severely, such as Zhejiang, Fujian Province and so on, high mutation frequencies were observed  (ranged from 31.3% to 100%), while in other regions where C. suppressalis occurred infrequently, such as Funan，Anhui Province, Deyang，Sichuan Province, the mutation freqencies were relatively low (ranged from 0% to 23%).

Select

Effects of Different Nitrogen Application Levels on Rice Nutrient Uptake and Ammonium Volatilization YU Qiaogang, YE Jing, YANG Shaona, FU Jianrong*, MA Junwei, SUN Wanchun, JIANG Lina, WANG Qiang, WANG Jianmei 2012, 26(4): 487-494.  DOI: 10.3969/j.issn.10017216.2012.04.015 Abstract ( )   PDF (814KB) ( )   The effects of different nitrogen application levels on nutrient uptake and ammonium volatilization were studied in a field experiment with rice variety Zheyou 12 as material. The results showed that  the accumulative amounts of nitrogen, phosphorus and potassium showed an increasing tendency with the increasing nitrogen application level  from 0 to 330  kg/hm2. The accumulative amounts of nitrogen, phosphorus and potassium decreased when the nitrogen application  level was above 270  kg/hm2. The accumulative amounts of nitrogen, phosphorus and potassium increased with organic manure addition at 150  kg/hm2 nitrogen application  level. The nitrogen uptake peaked   from jointing stage to heading stage, and also increased with the increasing nitrogen application  level   from 0 to 270  kg/hm2. The rice grain yields were positively correlated with the accumulative amounts of nitrogen, phosphorus and potassium. Among those,  the accumulative nitrogen   amount was most closely correlated with rice yield.  Velocity and  accumulative amounts of  ammonium volatilization  increased with the increasing nitrogen application  level. Compared with other stages, faster ammonium volatilization velocity and higher ammonium accumulative amount were observed several days after the basal  fertilizer was applied. Ammonium volatilization velocity at nitrogen application rate of 270  kg/hm2 and 330  kg/hm2 were far higher than those in other treatments. The ammonium nitrogen volatilization loss accounted for 23.9% of the total applied nitrogen at the nitrogen application level of 330  kg/hm2.

Experimental Techniques

Select

An Efficient, Economic, and Rapid Rice DNA Extraction Method and Its Application ZHAO Guozhen1, JIA Yulin2,*, YAN Zongbu3, Christopher W DEREN3, Melissa H JIA2, DAI Luyuan1,* 2012, 26(4): 495-499.  DOI: 10.3969/j.issn.10017216.2012.04.016 Abstract ( )   PDF (1993KB) ( )   A method for DNA extraction from rice leaf, root and seed was developed, and the extracted DNA was used as a template to successfully amplify the rice blast resistance gene Pita. Profiles of Pita in 165 breeding lines detected by DNA markers were verified using differential blast races. This method involved three steps: 1) Plant tissue was placed into a 200 μL 96well plate; 2) A total of 70 μL of Buffer A containing NaOH and Tween 20 was added to each sample and incubated at 95℃ for 10 min in a PCR machine; and 3) A total of 70 μL of Buffer B containing TrisHCl and EDTA was added to each well and the resulting solution used for PCR amplification. Results demonstrated that this method of DNA extraction has the following advantages: 1) It is economical and only 4 common chemicals totaling 140 μL were used; 2) It is easy to perform, consists of only three steps, and one technician can extract hundreds of samples per day; 3) It requires a standard PCR machine; and 4) It can efficiently extract DNA from as little as a half dried seed, 5 to 20 mg of leaf tissue, or 20 mg root tissue. The resulting DNA quality was good enough to detect a single copy of the rice blast resistance gene Pita which was verified in breeding lines with the expected disease reactions. This method has proven to be highly efficient for evaluating a large number of samples.

Select

Establishment and Preliminary Application of a Quantitative Realtime PCR Method for Detection of Conidia of Ustilaginoidea virens  ZHENG Jing1，2， ZHANG Zhen2，*， JIANG Hua2， WANG Yanli2， CHAI Rongyao2， QIU Haiping2， MAO Xueqin2，WANG Jiaoyu2， DU Xinfa2， LAN Zhaohui3， SUN Guochang2，* 2012, 26(4): 500-505.  DOI: 10.3969/j.issn.10017216.2012.04.017 Abstract ( )   PDF (1346KB) ( )   A realtime PCR quantitative detection technology was established by using two pairs of specific primers designed according to the internal transcribed spacer (ITS) sequences of Ustilaginoidea virensand their corresponding TaqMan probes. The results showed that the combination of the specific primers and probe of uvr292rf/uvr397rr/uvrp333 was highly sensitive and specific in the quantification of U. virens with a minimum detection limit of 24 fg. A linear model between Ct and common logarithm of spores number was established by realtime PCR with the templates of DNA from diluted spores solution and the theoretical detected limit was 0.67 spore. According to the quantitative detection of three air samples collected in paddy field at various time with this linear model,  the quantity of this fungus conidia fluctuated monthly.

Short Communications

Select

Identification and Genetic Analysis of Resistance of a Rice Germplasm 911A② to Rice Gall Midges LU Jiashi1,2, HE Longfei1,*, XU Jing1, XU Chunyan1, LI Chuangzhen1, WEI Sumei3 2012, 26(4): 506-510.  DOI: 10.3969/j.issn.10017216.2012.04.018 Abstract ( )   PDF (387KB) ( )   The resistance of a rice germplasm 911A② to the rice gall midge(GM) was identified and genetically analyzed. 911A② was used as male parent to hybridize, test cross with Jinggui, TN1, W1263（Gm1）, IET2911（Gm2）, BG4041（gm3）, OB677（Gm4）, ARC5984（Gm5）and Duokang 1（Gm6）,    and their F1 selfpollinated，   respectively. The resistance of all parental lines and the populations of F1, BC1F1, F2  to the rice gall midge were identified.  The resullts showed that 911A② and all F1 resist to rice gall midge biotype Ⅳ of China. The segregation ratio of resistant plants to sensitive ones to rice gall midge biotype Ⅳ of China of BC1F1 and F2 accorded with 1(resistant)∶3(sensitive) and 9(resistant)∶7(sensitive) rule by χ2 test, suggesting that the resistance of 911A② to rice gall midge biotype Ⅳ of China was controlled by two dominant genes, which was nonallelic to the known resistant genes Gm1, Gm2, gm3, Gm4, Gm5and Gm6, as well as the other five resistant genes Gm7，Gm8，Gm9，Gm10, Gm11（t）. It suggested that the two genes are new rice gall midge resistance genes.