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10 April 2003, Volume 17 Issue 2 Previous Issue    Next Issue
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研究报告
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Analysis of Introgressed Segments in Near-Isogenic Lines for F1 Pollen Sterility in Rice LI Wen-tao,ZENG Rui-zhen,ZHANG Ze-min,ZHANG Gui-quan * 2003, 17(2): 95-99 .  Abstract ( )   PDF (187KB) ( )   One hundred and fifty eight microsatellite markers,with polymorphism among parents were used to survey the introgressed segments in 50 F 1 pollen sterility near isogenic lines. Two hundred and sixty introgressed segments were detected in 50 introgression lines, each carrying 5.2 introgressed segments. Among them,100 introgressed segments carrying F1 pollen sterility loci concentrated on the region of F 1 pollen sterility genes while 160 introgressed segments not related to F1 pollen sterility loci distributed randomly over 12 chromosomes. Both the average number and length of introgressed segments decreased along with the increase of backcross generations. The number of introgressed segments was less than four and the length of introgressed segments was less than 20 cM beyond the third generations (BC3).

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Genetic Identification of a New Small Grain Dwarf Gene in Rice WU Cheng ,LI Xiu-lan ,DENG Xiao-jian ,LI Ren-duan ,YANG Zhi-rong 2003, 17(2): 100-104 .  Abstract ( )   PDF (169KB) ( )   Rice line 162d was a new small grain dwarf mutant. Analyses of 221 SSR loci demonstrated that 162d was derived from Shuhui 162 through mutation, and 162d and Shuhui 162 were a pair of near isogenic lines. Genetic analyses of F1 and F2 populations suggested that the dwarfism of 162d was controlled by a recessive gene. Phenotypic characteristics of the dwarf gene were that plant height was about one fourth of normal height, grain volume was about one fourth of normal volume, seed setting rate was very low and leaf was short and broad, compared with Shuhui 162. The dwarf gene was sensitive to gibberellin (GA3), and was not located on the area near centromere of rice chromosome 5, where d1 gene located. Therefore, it was considered that the mutant gene of 162d was a new small grain dwarf gene in rice.

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Expression and Mapping of cDNA Fragments Responsive to Magnaporthe grisea in Rice RAO Zhi-ming ,DONG Hai-tao ,ZHUANG Jie-yun ,CHAI Rong-yao ,FAN Ye-yang ,LI De-bao ,ZHENG Kang-le 2003, 17(2): 105-108 .  Abstract ( )   PDF (295KB) ( )   The expression profiles of a resistant line G205 derived from a RIL population of Zhong 156×Gumei 2 in response to Magnaporthe grisea were investigated by using cDNA microarray containing 2200 expressed sequence tags (ESTs). One cDNA fragment encoding nucleotide binding site (NBS) and leucine rich repeat (LRR) was up regulated and the other cDNA fragment encoding nitrilase associated protein (NIT) was down regulated significantly by the fungus, which were confirmed by Northern blot. They were mapped on chromosomes 2 and 3 by RFLP analysis respectively. Both of them were located on the intervals where QTLs controlling partial resistance to blast had been detected.

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cDNA Cloning and Sequence Analysis of Rice Sbe1 and Sbe3 Genes CHEN Xiu-hua ,LIU Qiao-quan ,WU Hsin-gang ,WANG Zong-yang ,GU Ming-hong 2003, 17(2): 109-112 .  Abstract ( )   PDF (243KB) ( )   The starch branching enzyme (SBE) is a key enzyme in amylopectin biosynthesis and there are two major isoforms in rice, named SBEⅠ and SBEⅢ, which are encoded by the Sbe1 and Sbe3 genes, respectively. These two genes were cloned from the template cDNA library, which was synthesized by improved RT PCR technique from the mRNAs of the immature rice seeds of japonica rice Wuyunjing 7. DNA sequencing analysis showed that the size of the cloned Sbe1 and Sbe3 cDNAs were 2490 bp and 2481 bp, respectively, and carried their entire coding sequences. Comparison analysis indicated that the Sbe3 sequence was the same as the reported and their homology was 100%. There were only four base pairs difference, which resulted in two deduced amino acids alteration, between the cloned Sbe1 cDNA and the reported.

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SCAR Markers Assisted Selection for a Bentazon Susceptible Lethality Gene (ben) in Rice XIANG Tai-he ,YANG Jian-bo ,YANG Qian-jin ,ZHU Qi-sheng ,LI Li ,HUANG Da-nian , 2003, 17(2): 113-117 .  Abstract ( )   PDF (1490KB) ( )   With rice cultivar Norin 8m susceptible to bentazon as donor of ben gene, SCARs tightly linked to ben were utilized for selection of ben. Results showed that homozygous and heterozygous genotypes with ben could be identified with the SCARs. The molecular markers offered a powerful tool for indirect selection of ben and could accelerate the introgression of ben into current rice cultivars.

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Genetic Diversity of Rice Cultivars Resistant to Bacterial Blight in Yunnan JI Guang-hai,QIAN Jun,ZHANG Shi-guang,WEI Lan-fang,CHEN Xing-quan 2003, 17(2): 118-122 .  Abstract ( )   PDF (948KB) ( )   The genetic diversity was analysed in 53 rice cultivars with resistance to bacterial blight by RAPD. Twenty random primers were selected from 90 ones screened. Results showed that these cultivars exhibited extensive genetic variability and abundant genetic diversity. Cluster analysis based on DNA data revealed that there were significant differences between the resistant and susceptible cultivars. Fifty one of them could be divided into 13 groups, Group 1,2, and 5 were predominant, including 8,17, and 9 cultivars, respectively. Thus the genetic characteristics of rice clusters showed bacterial blight resistance, it may be useful in rice breeding for developing resistant cultivars to control the disease.

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Genetic Diversity of Allozyme Associated with Morphological Traits in Chinese Improved Rice Varieties WEI Xing-hua ,TANG Sheng-xiang ,JIANG Yun-zhu ,YU Han-yong ,QIU Zong-en ,YAN Qi-chuan 2003, 17(2): 123-128 .  Abstract ( )   PDF (191KB) ( )   Seven hundred and forty four Chinese rice improved varieties with different ecotypes bred in 1931-1998 were selected to detect the genetic diversity by 12 allele loci of five allozymes and analyze the correlation between allozyme distance and morphological traits distance. Results showed that the percentage of polymorphic loci (P), average allele number(A), average effective allele number (Ae), Shannon’s index(I), and Nei's gene diversity index(He)of Chinese rice improved varieties were 100%, 3.167, 1.515, 0.452, and 0.272, respectively. The allele frequencies were different between indica rice and japonica rice. The genetic diversity of indica rice was higher than that of japonica rice. I and He of indica rice were 1 702 fold and 1.730 fold as many as those of japonica rice, respectively. The genetic diversity of Central China rice region was highest (He=0.283) and that of Northeast China rice region was lowest (He=0.062) in the six rice regions in China. The correlations between allozyme distance and morphological traits distance were ranged from 0.163 to 0.390, and significant at 0.05 or 0.01 level, respectively, in rice regions of China (except Southwest China rice region).

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Distribution of the Classification Traits in the F2 Progeny of Two Crosses of Indica/Japonica in Rice (Oryza sativa) ZHANG Zai-jun ,LIANG Cheng-ye 2003, 17(2): 129-133 .  Abstract ( )   PDF (180KB) ( )   Comparison of seed setting rate, plant height and Cheng's morphological traits were made between the F2 progeny of indica japonica hybrids 02428/Pei'ai 64 and Taichung 65/Teqing. Results showed that there existed resemblance normal distribution in plant height and the distribution was not related with the seed setting rate and plant height in F1 progeny, suggesting that there was no gametic selection for the plant height in the F2 progeny of indica japonica hybrids. Average seed setting rates of the F2 and F1 populations were equal in the rcombination of 02428/Pei'ai 64 with excellent compatibility, but the remarkable increase of seed setting rate from F1 to F2 in Taichung 65/Teqing, indicating that gametic selection only took place in indica-japonica crosses with low compatibility, and null or little in the hybrids with high compatibility. There were many intermediate types of leaf hairness, color of hull at heading and length of the first and second panicle internode, these Cheng's morphological traits were normal distribution, also, there were a little intermediate types in hull hairness and phenol reaction with bi-peak distribution, and the ratios of lenth to width of grain were inclined to japonica types obviously and these traits showed a skewed distribution in F2 population. Although Cheng's morphological traits in F2 populations had inconsistent distribution types, Cheng's morphological traits index was normal distribution, showed that intermediate types, i.e. indicalinous or japonicalinous, were primary in F2 population.

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Comparison of Grain Quality Between F1 Hybrids and Their Parents in Indica Hybrid Rice LIAO Fu-ming,ZHOU Kun-lu,YANG He-hua,XU Qu-sheng 2003, 17(2): 134-140 .  Abstract ( )   PDF (226KB) ( )   Sixteen widespread elite indica parents including seven CMS lines and nine restorer lines and their 63 F 1 hybrids were chosen to compare 11 characters of grain quality between F1 hybrids and their parents in indica hybrid rice. Based on the test results of relative heterosis of all characters in all hybrids, the frequency of negative dominance and heterosis was much higher than that of positive dominance and heterosis, indicating that the values of F1 hybrids were lower than the means of their parents in quality characters as a whole. There existed apparent disparity in grain quality performance among F1 hybrids which varied with characters. The characters of chalky area percentage, chalky rice percentage, gel consistency and head rice had a great variation in all kinds of tested heterosis indices including mid parent heterosis index, heterosis index over high value parent, and heterosis index over low value parent, which suggest that special attention should be paid to selection of F 1 hybrids in these characters in breeding. The mean values of F 1 hybrids were significantly lower than those of their higher parents in all characters at 0.05 or 0.01 levels; close to or significantly (P=0.01) lower than those of their mid parent values in all characters except for milled rice length and amylose content; and significantly (P=0.05 or 0.01) higher than those of their lower parents in all characters except for brown rice, milled rice and gel consistency.

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Roots Distribution of Rice in Field and Its Relation to Soil Bul Density ZHANG Yu-ping ,ZHU De-feng ,LIN Xian-qing ,JIAO Gui-ai ,HUANG Qun 2003, 17(2): 141-144 .  Abstract ( )   PDF (147KB) ( )   Experiments were carried out with super high yielding three line hybrid rice Xieyou 9308 and two line hybrid rice Liangyoupeijiu in the field and pot experiment. Results showed that 89%-98% of roots distributed within 15 cm of soil layer at panicle initiation and flowering stage in the field conditions and percentage of deep roots between hills was higher than that in the center of hills. Roots biomass and percentage of deep roots of Xieyou 9308 with lower senescence of leaf was higher than those of Liangyoupeijiu. Under the higher soil compaction, root biomass decreased, and the amount and percentage of deep roots decreased also. Effects of deep tillage on root growth and distribution of rice were discussed.

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Effect of Temperature on Pollen Fertility in Inter-Subspecific Rice Hybrids YANG Jie ,WAN Jian-min ,ZHAI Hu-qu ,WANG Cai-lin ,ZHONG Wei-gong ,ZOU Jiang-shi 2003, 17(2): 145-148 .  Abstract ( )   PDF (158KB) ( )   Seventeen rice cultivars and hybrids in different types (indica, japonica, javanica, indica hybrid, japonica hybrid and inter subspecific hybrid ) were evaluated to determine the effect of temperature on pollen fertility. Results showed that the pollen fertility of inter subspecific hybrids was greatly reduced at miosis stage when the average daily temperature dropped to 22.0-23.0℃, and the extent of pollen fertility reduction varied greatly in different hybrids. However, the pollen fertility reduction of indica and japanica hybrids and conventional cultivars was not obvious under the same temperature conditions. When the average daily temperature dropped to 20℃, pollen development of conventional cultivars and hybrids was also affected. Correlation analysis revealed that there existed positive correlation between pollen fertility and average daily temperature. The significant difference(P<0.01) was also detected between the two correlation coefficients: Inter subspecific hybrids and conventional cultivars. Temperature at miosis stage was a key factor to pollen development, and the pollen fertility of inter subspecific hybrids was more sensitive to low temperature than that of conventional variety.

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Effects of Endogenous IAA on Grain Filling of Hybrid Rice TAO Long-xing,WANG Xi,HUANG Xiao-lin 2003, 17(2): 149-155 .  Abstract ( )   PDF (267KB) ( )   By using hybrid rice Xieyou 9308, Xieyou 9312, Ⅱyou 162 and their restorer lines as plant materials, and 3H glucose, PCIB, TIBA as chemical materials, the process of grain filling and effects of IAA, TIBA, PCIB on sugar content in superior and inferior spikelets were studied. The overall contents of IAA and grain weight increment rate in superior spikelets were higher than those in inferior spikelets. The sugar contents (fructose, glucose, sucrose) in inferior spikelets were not higher than those in superior spikelets until 7 days after pollination, and higher than those in superior ones after that time. Physiological activity differences between superior and inferior spikelets were more significant in hybrid rice combinations than those in their restorer lines. IAA inhibitors decreased IAA contents in both superior and inferior spikelets and reduced 3H glucose radiaton activity. By treated with high concentration exogenous IAA on young panicle before heading, the seed setting rate difference between superior and inferior spikelets was significantly decreased, and the total seed setting rate was increased.

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Photoinhibition and Recovery Properties of Hybrid Rice Ⅱyou 129 under Natural Condition XU Xiao-ming ,LU Wei ,TANG Yun-lai ,DENG Zhi-rui ,DAI Xin-bin ,ZHANG Rong-xian ,KUANG Ting-yun 2003, 17(2): 156-160 .  Abstract ( )   PDF (173KB) ( )   Photoinhibition properties of super high yielding hybrid rice Ⅱyou 129 and its adaptation mechanism to strong light were investigated by measuring its light response curve, diurnal variation of net photosynthetic rate and chlorophyll fluorescence parameters of leaves, with hybrid rice Shanyou 63 as a control. Results indicated that photoinhibition of rice flag leaves under field conditions mainly resulted from increasing in thermal dissipation, especially for the thermal dissipation depended on xanthophyll cycle, but no destruction of photosynthetic apparatus. Super high yielding rice Ⅱyou 129 was more tolerant to photoinhibition than Shanyou 63. This is attributed to higher saturation light intensity and maximum net photosynthetic rate, more active xanthophyll cycle, and more rapid recovery after photoinhibition of Ⅱyou 129 compared to Shanyou 63.

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Physiological Characteristics of Zn-Efficient Rice Genotype CHEN Guang-cai ,WANG Ren-min ,ZHANG Yong-xin ,YANG Xiao-e 2003, 17(2): 161-165 .  Abstract ( )   PDF (197KB) ( )   The physiological characteristics of rice in different Zn2+ activities(pZn2+ >11.5, 11.3, 11.0, 10.6, 10.3, 9.7) were studied with the Zn efficient rice cultivars IR34,IR36,IR8192 and Zn inefficient rice cultivars IR26, Ce64 7, Biyuzaonuo grown in chelator buffered nutrient solution. There was significant difference in tolerance to zinc deficiency among different rice genotypes. Obvious effects of low zinc activities were noted on physiological characteristic of rice seedlings. There were obvious differences among chlorophyll content, photosynthetic rate, MDA concentration and H + excretion of root. As pZn2+ increased, chlorophyll content and photosynthetic rate decreased at a slower pace in Zn efficient cultivars compared to Zn inefficient cultivars, MDA concentration increased slower while H+ excretion of root increased faster in Zn efficient cultivars than those in Zn inefficient cultivars.It was suggested that the above indications could be used as indices to Zn efficiency of rice.

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Relationship Between Methamidophos Resistance Development and Three Detoxifying Enzymes in Brown Planthopper LIU Ze-wen,HAN Zhao-jun,ZHANG Ling-chun 2003, 17(2): 166-170 .  Abstract ( )   PDF (178KB) ( )   Methamidophos resistance of brown planthopper, Nilaparvata lugens (BPH) was selected in laboratory. Results showed that the resistance development of BPH was approximatively shaped as the letter “S”: resistance change was small before the fifth generation and after the fifteenth generation, and the change was sharp between the fifth and the fifteenth generation. Esterase might play an important role in the resistance development, because the esterase activity and the number of individuals with high activities increased along with the resistance development. The esterase activities of insecticide sensitive population, field population F0, and its selective generations F5, F10 and F15 were high correlated with the resistance ratios of these generations, and the coefficient was 0.98993. Mixed function oxidases and glutathione S transferase also might play some roles in the resistance development, but the big change in the activities of the two detoxifying enzymes both took place before the tenth generation.

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The Sex Pheromone of Rice Stem Borer, Chilo suppressalis in Paddy Fields: Suppressing Effect of Mass Trapping with Synthetic Sex Pheromone SU Jian-wei,XUAN Wei-jian,SHENG Cheng-fa,GE Feng * 2003, 17(2): 171-174 .  Abstract ( )   PDF (156KB) ( )   Suppressing effect of mass trapping of synthetic sex pheromone against the rice stem borer during the flight periods of over wintering and the 1st generation was investigated in rice field in Lujiang County, Anhui Province in 1999. Results showed that population density of rice stem borer in pheromone treated plot was lower than that of the control. The number of egg masses per 100 tiller decreased by 74.39% and population size of adult males of the 1st generation decreased by 61.41% as compared with the control. Meanwhile, damage by the stem borer larvae in pheromone treated plot was lower than that of the control and there was significant difference (t test, P=0.05). Percentages of brownish leaf sheath per 100 tiller, dead heart plant and white head plant decreased by 70.90%, 57.01% and 44.30%, respectively as compared with the control. Significance of these results was discussed in the context of integrated management of the rice stem borer. It might be concluded that mass trapping by using synthetic sex pheromone of rice stem borer is an environment friendly alternative to chemical insecticides.

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Indirect Impact Assessment of Transgenic Rice with cry1Ab Gene on Predations by the Wolf Spider, Pirata subpiraticus LIU Zhi-cheng ,YE Gong-yin ,FU Qiang ,ZHANG Zhi-tao ,HU Cui 2003, 17(2): 175-178 .  Abstract ( )   PDF (146KB) ( )   Predation amounts and functional responses by the wolf spider, Pirata subpiraticus on the rice leaffolder, Cnaphalocrocis medinalis, and the brown planthopper, Nilaparvata lugens, which were fed with transgenic rice with cry1Ab gene, were evaluated under laboratory conditions. Both on these two preys, functional responses by the spider followed the Holling “disc equation” for typeⅡresponse. When the larvae of the leaffolder fed with leaves of transgenic rice with cry1Ab gene were used as the prey, the killed amount and handling time by the spider were lower than those of the control, but the differences were not significant, whereas the attack constant performed significantly lower than that of the control. The killed amount and handling time as well as the attack constant by the spider showed some difference from those of the control, and these differences did not reach the significant level as the planthopper nymphs reared on the transgenic rice plants were as the preys. To consider the tested results, it may be drawn that there was no marked adverseness of transgenic rice with cry1Ab gene on the predation by the wolf spider.

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Effect of Exogenous Enzyme on Growth and Digestion of Pigs Fed Paddy-Based Diets WANG Min qi,XU Zi-rong,SUN Jian-yi 2003, 17(2): 179-183 .  Abstract ( )   PDF (232KB) ( )   Sixty growing pigs (Landrace×Jia) were used to study the effects of adding exogenous enzymes (including β glucanase, xylanase and cellulase) to paddy based diets on growth performance and digestion in growing finishing pigs. Results showed that with the supplementation of enzymes, average daily gain of pig was increased by 8.78%(P<0.05) and feed gain ratio was decreased by 9.42%(P<0.05); feed apparent digestibilities of crude protein, extrude ether, and crude fiber were increased by 12.73% (P<0.01), 8.84%(P<0.05), and 16.97%(P<0.01), respectively; the viscosity of jejunum,ileum contents were reduced by 7.08%(P<0.01), and 6.78%(P<0.01), respectively; numbers of E. coli in feaces and diarrhoea morbidity were decreased by 81.29%(P<0.01), and 37.00%(P<0.05) respectively; the activities of protelytic enzyme and α amylase in duodenal contents were increased by 99.07% (P<0.05), and 18.38%(P<0.05), respectively.

研究简报

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Hybrid Rice Resistant to Bacterial Blight Developed by Marker Assisted Selection CAO Li-yong,ZHUANG Jie-yun,ZHAN Xiao-deng,ZHENG Kang-le,CHENG Shi-hua * 2003, 17(2): 184-186 .  Abstract ( )   PDF (804KB) ( )   Through recurrent backcrossing in combination with molecular marker assisted selection (MAS), restorer lines R8006 and R1176 carrying Xa-21, a gene having broad spectrum resistance to bacterial blight, were selected. By crossing the two lines to CMS line Zhong 9A, two new hybrid rice combinations, Zhongyou 6 and Zhongyou 1176 were developed. The hybrids showed high resistance to diseases, good grain quality and high yielding potential in national and provincial adaptability and yield trials.

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Adsorption of Phosphate by Iron Plaque on Rice Roots in Relation to Phosphate Uptake by Rice CAI Miao-zhen,LUO An-cheng,ZHANG Yong-song,LIN Xian-yong,YE Ji-shu 2003, 17(2): 187-190 .  Abstract ( )   PDF (152KB) ( )   Two rice genotypes differed in tolerance to iron toxicity were used to investigate the adsorption of phosphate by iron plaque on rice roots and subsequent effect on P absorption by rice. Great variation in quantities of iron plaque was observed between two genotypes, resulting in the difference in phosphate adsorption. The amount of P adsorbed increased with the increasing quantity of iron plaque on rice roots, which was indicated by a significant positive correlation between the quantity of iron plaque and its phosphate adsorbed. Phosphate adsorbed by iron plaque was likely to be a chemical process which was accomplished within 0.5-1.0 hour. The accumulation of phosphate by iron plaque remarkably enhanced the phosphorus uptake by rice, which suggested that the adsorbed phosphate was an important pool of phosphorus available to rice under the flooding conditions.