Archive

10 March 2007, Volume 21 Issue 2 Previous Issue    Next Issue
---
研究报告
Reviews and Special Topics
研究报告
研究简讯
研究简报


For Selected:

Download Citations EndNote Ris BibTeX

Toggle Thumbnails

研究报告

Select

cDNA Cloning and Expression Analysis of GluB-6 in Rice NIU Hong-bin ,WANG Yi-hua ,ZHAI Hu-qu ,WAN Jian-min 2007, 21(2): 111-116 .  Abstract ( )   PDF (934KB) ( )   Based on the conserved amino acid sequences of rice glutelin gene family, one highly homologous BAC clone sequence from the rice genome database of GenBank was obtained and a putative glutelin gene was predicted. After amplified by RT-PCR with the specific primers designed on the basis of predicted nucleotide sequence, a new glutelin gene cDNA, named GluB-6(GenBank accession number is AY429651), was cloned. DNA sequencing analysis and in vitro expression results showed that the cloned cDNA was 1517 bp, and carried entire coding sequences,which encoded a 495 amino acid protein; this corresponded to the size of the glutelin protein family. Homology analysis showed that the deduced amino acid sequence of GluB-6 shared 53.6%-82.8% identity with rice glutelin gene family other else. Northern blot analysis indicated that GluB-6 expressed especially in rice endosperm.

Select

SSR Analysis on Nuclear Genome of Isonuclear Alloplasmic Male Sterile Lines and Their Maintainer Lines in Rice (Oryza sativa) LI Jin-quan ,LI Wei ,CHENG Gui-ping ,CAI Shan-xin ,FENG Jiu-huan 2007, 21(2): 117-122 .  Abstract ( )   PDF (74KB) ( )   Four sets of rice isonuclear alloplasmic lines,including 15 male sterile lines and their maintainer lines were analyzed by using 42 SSR markers,which were randomly selected from 12 chromosomes of rice.A total of 63 alleles were detected in the 15 lines.The frequency of polymorphic loci was 40.48%,the average number of alleles per locus was 1.5,and the average gene diversity was 0.18.Four sets of the isonuclear alloplasmic male sterile lines shared 54.5 identical loci,corresponding to 86.51% of the total alleles;and meanwhile,there were 8.5 different loci between them,it was equal to 13.49%.Average 77.78% identical loci and 22.22% different loci were detected between the isonuclear alloplasmic male sterile lines and their maintainer lines.Similarly,average 53.97% identical loci and 46.03% different loci were existed among the homogenous allonucleus male sterile lines.The SSR fingerprints for some male sterile lines and maintainer lines were established.Based on the cluster analysis,the 15 lines could be divided into three groups at the 0.22 of the genetic distance.The first group consists of eight lines including the male sterile lines and their maintainer lines of Huanong A and Huayu A.The second group consists of three sterile lines of Kezhen 2A,including N9A,N10A and N11A.The third group includes four isonuclear alloplasmic lines of Zhenshan 97A,i.e.,N12A,N13A,N14A and N12-16B.The isonuclear alloplasmic lines of the same sets are mostly clustered in the same group,which is consistent with their pedigrees.

Select

QTL Analysis for Amylose Content and Protein Content Predicted by Near Infrared Spectroscopy (NIRS) in Rice under Normal or Water Stress Conditions LI Ying ,MEI Han-wei ,WU Jin-hong ,ZHANG Hong-jiang ,FENG Fang-jun ,XU Xiao-yan ,LUO Li-jun 2007, 21(2): 123-130 .  Abstract ( )   PDF (127KB) ( )   Amylose content(AC),protein content(PC)of a recombinant inbred line population with 187 lines from the cross between Zhenshan 97B and IRAT109,were investigated under water stress and normal conditions.The result showed that PC under water stress was significantly lower than that under normal conditions,but the difference in AC was not significant.A total of 22 main effect QTLs and 66 pairs of epistasis were associated with AC and PC.The accumulated contributions of main effect QTLs for AC and PC were 35.34%,37.33% under normal conditions and 53.40%,58.10% under water stress condition,and the accumulated contribution of digenic epistasis for AC and PC were 66.74%,57.49% under normal conditions and 48.65%,36.59% under water stress conditions,respectively.

Select

Source and Inheritance of within Cultivar Residual Variation Detected in an indica Rice Variety IR64 WU Jian-li ,SHI Yong-feng ,CHEN Jie ,Casiana VERA CRUZ ,ZHUANG Jie-yun ,Hei LEUNG ,ZHENG Kang-le 2007, 21(2): 131-135 .  Abstract ( )   PDF (189KB) ( )   The phenotypically uniform indica rice variety IR64 was chosen for study of the source and inheritance of within cultivar residual variation using a set of SSR markers.Molecular heterogeneity in IR64 was identified on the short arm of chromosome 2 involving at least five SSR loci spanning nearly 30 cM.The SSR variations originated from the parental lines of IR64(IR5657-33-2 /IR2061-465-1-5-5)and were segregating in the selfed bulk seed stock in a Mendelian manner for more than 20 years.This study was one of few examples to verify successfully that within cultivar variations of SSR in morphologically uniform selfing crops came from its parental lines,which has immediate and commercial applications including test of seed purity,varietal fingerprinting,and curation and propagation of germplasm collections.

Select

Breeding Value and Further Mapping of a QTL qSB-11 Conferring the Rice Sheath Blight Resistance ZUO Shi-min ,YIN Yue-jun ,ZHANG Li ,ZHANG Ya-fang ,CHEN Zong-xiang ,PAN Xue-biao 2007, 21(2): 136-142 .  Abstract ( )   PDF (428KB) ( )   The breeding effect of a resistant QTL qSB-11,with a resistant allele(qSB-11Le)for the rice sheath blight located on chromosome 11 of a susceptible variety Lemont,was investigated.Under severe disease conditions,the lines carrying the qSB-11 Le allele could reduce yield loss up to 10.71% compared to those without this allele.However,no significant difference in yield between the two lines was noted when they were disease-free or slightly infected.By using polymorphic markers and BC4F2 segregating population at the region containing qSB-11Le,the interval covering qSB-11Le was reduced to 1000 kb in length between the two molecular markers,Z405 and Z286.Therefore,the qSB-11Le allele was considered to have a considerable potential in breeding for resistance to rice sheath blight.The molecular markers linked to qSB-11Le developed in the study would be useful to incorporate this favorite allele into elite rice lines via marker assisted selection(MAS).

Select

Genetic Relationships Between Wx Gene and Starch Quality in Autotetraploid and Diploid Rice LIU Yu-hua ,LUAN Li ,LONG Wen-bo ,WANG Xing ,KONG Fan-lun ,HE Tao ,TU Sheng-bin 2007, 21(2): 143-149 .  Abstract ( )   PDF (224KB) ( )   Wx genotypes of 40 autotetraploid rice and 14 diploid rice were tested by using the(CT)n microsatellite marker and a cleaved amplified polymorphic sequence(CAPS)molecular marker named PCR-Acc Ⅰ.Three microsatellite alleles were produced,i.e.Wx1,Wx2 and Wx3 in both autotetraploid and diploid rice.Comparatively,PCR-Acc Ⅰ molecular marker produced two genotypes,G-type and T-type for both autotetraploid and diploid rice.Analysis on relationship between amylose content(AC),gel consistency(GC)and gelatinization temperature(GT)of rice and Wx alleles showed that both AC and!GC were closely related to Wx genotypes,i.e.the materials with Wx1 genotype and G-type of Wx gene had higher AC and hasder GC,however,the materials with Wx2,Wx3 genotypes and T-type of Wx gene had lower AC and softer GC.On the other hand,GT was not significantly correlated with AC and Wx genotype,indicating that AC and GC of rice grain were probably controlled by Wx gene or other gene whose location was strictly linked to Wx gene,while GT of rice was not.Analysis by using microsatellite marker and PCR-Acc Ⅰ molecular marker showed that 92.0% of Wx1genotypes were G-type,but all Wx2and 80.0% of Wx3 genotypes were T-type in autotetraploid rice.The coefficient of correlation between Wx genotypes which revealed by(CT)n microsatellite marker and PCR-Acc Ⅰ molecular marker was 0.842,statistically significant at the level of 0.01.

Reviews and Special Topics

Select

A Comparative Study on SSR Diversity in Chinese Major Rice Varieties Planted in 1950s and During the Most Recent Ten Years HUA Lei ,YUAN Xiao-ping ,YU Han-yong ,WANG Yi-ping ,XU Qun ,TANG Sheng-xiang ,WEI Xing-hua 2007, 21(2): 150-154 .  Abstract ( )   PDF (37KB) ( )   A total of 40 SSR markers were used to compare the genetic diversity in 151 Chinese major rice varieties planted in 1950s and during the most recent ten years.Of the 40 SSR loci,39 were polymorphic while 1 locus(RM479)was found to be monomorphic.All the 39 polymorphic loci revealed a total of 213 alleles.The mean number of alleles per locus(Na)was 5.5 with a range from 2 to 11.Total genetic diversity index of Nei(He)varied greatly among loci from 0.309 at RM174 to 0.869 at RM418,with an average value of 0.649.There existed a significant difference in SSR allelic diversity between indica and japonica subspecies.Indica rice had more variation than japonica rice both for Na and He.By comparison of the genetic changes in Na and He,it was found that varieties planted in 1950s had more alleles and higher He than those in recent ten years both for indica and japonica rice.The difference between two subspecies was significant in a tendency for Na over time(indica:z= 2.677,P= 0.007;japonica:z= 3.441,P=0.001),but not for He(indica:z= 1.471,P= 0.141;japonica:z= 1.932,P= 0.053).Analysis of molecular variance(AMOVA)indicated that the genetic variation was significantly different(P< 0.05)between the periods of the 1950s and the recent ten years,of which,more genetic variation was contributed by indica(Fst= 0.050)and japonica(Fst= 0.082)subsets.Using locus-by-locus AMOVA procedure,significant differentiations were observed in 13 loci for indica subset and 11 loci for japonica subset between periods.It was found a part of the genetic alleles was lost in current major rice varieties as comparison with those of 1950s.Therefore,more alien elite genetic resources should be explored in the current program of Chinese rice breeding.

研究报告

Select

Discussion on Photoreceptor for Negative Phototropism in Rice Root WANG Yue-xia ,WANG Zhong ,SUO Biao ,GU Yun-jie ,WANG Hui-hui ,ZHANG Wen-hu ,KONG Yu 2007, 21(2): 155-158 .  Abstract ( )   PDF (947KB) ( )   To properly explore the photoreceptor for the negative phototropism in rice(Oryza sativa L.)root,lights with different wavelengths were applied to investigate the effect of light quality on phototropic response.The negative phototropic bending could be induced prominently by blue/UV light,while not be induced by red and far-red light.Absorption spectrum of the extracted solution from rice cap had two peaks under 350 nm and 450 nm accordingly,and the molecular weight of the 120 kD protein of the cap under unilateral light was larger than that under the dark.It suggested that the blue light receptor might be the photoreceptor for the negative phototropism in rice root.

Select

New Vegetation Index and Its Application in Estimating Leaf Area Index of Rice WANG Fu-min ,HUANG Jing-feng ,TANG Yan-lin ,WANG Xiu-zhen 2007, 21(2): 159-166 .  Abstract ( )   PDF (174KB) ( )   Leaf area index(LAI)is not only an important attribute of land surface vegetation system,but also a key parameter for the models of global water balancing and carbon circulation.First of all,the reflectance values of Landsat-5 blue,green and red channels were simulated from rice reflectance spectrum.Secondly,the sensitivity of the bands to LAI was analyzed.Thirdly,the response and capability to estimate LAI of various NDVIs,which were established by substituting the red bands of general NDVI with all possible combinations of red,green and blue bands,were assessed.Finally,the conclusion was tested by rice data at different conditions.The result indicated that the sensitivity of red,green and blue bands to LAI were different under different conditions.When LAI is less than 3,red and blue bands are more sensitive to LAI.Though green band in the circumstances is less sensitive to LAI than red and blue bands,it is sensitive to LAI in a wide range.When the vegetation indices were constituted by all kinds of combinations of red,green and blue bands,the premise of making the sensitivity of these vegetation indices to LAI meaningful is that the value of one of the combinations is greater than 0.024,that is VIS>0.024.Otherwise,the vegetation indices would saturate,which would result in lower estimation accuracy of LAI.The capabilities of these vegetation indices derived from all kinds of combinations of red,green and blue bands to LAI estimation were compared.GNDVI and GBNDVI have the best relation with LAI.The capability of GNDVI and GBNDVI to LAI estimation was tested under different circumstances,and the same result was acquired.It can be seen that GNDVI and GBNDVI performed better to predict LAI than the conventional NDVI.

Select

Characteristics of Growth,Development and Nutrient Uptake in Rice under Site-Specific Nitrogen Management LIU Li-jun ,XU Wei ,WU Chang-fu ,YANG Jian-chang 2007, 21(2): 167-173 .  Abstract ( )   PDF (223KB) ( )   With typical rice cultivars as materials,the growth and development characteristics and nutrient uptake in rice under site-specific nitrogen management(SSNM)were studied.SSNM could decrease N rate to a greater extent without any sacrifice in grain yield,when compared with farmers’ fertilizer practice(FFP).Number of productive panicles under SSNM was a little lower than that under FFP,but productive tiller rate was much higher under SSNM.Leaf area index(LAI)and root weight were lower under SSNM than those under FFP before panicle initiation,but the results were reversed after heading stage.SSNM increased efficient and high efficient LAI rates at the heading stage,dry matter accumulation from heading to maturity stage,ratio of root to shoot,photosynthetic rate in flag leaves after heading stage and light transmission rate in rice population at the full heading stage.The uptake peaks of N,P,K under SSNM were all from panicle initiation to heading.During this period,the uptakes of N,P,K were about 45.6%-46.2%,39.6%-43.6%,and 44.2%-45.2% of total at maturity,which were all much higher than those under FFP.Reasons for yield increase and nutrient uptake laws in rice under SSNM were discussed.

Select

Difference in Grain-Filling Properties and Leaf Photosynthetic Characteristics at Late Growth Stage Between japonica Hybrid and Conventional Rice for Late Season in Southern China CHENG Wang-da ,YAO Hai-gen,ZHANG Hong-mei 2007, 21(2): 174-178 .  Abstract ( )   PDF (85KB) ( )   The grain filling processes of late japonica hybrid and conventional rice cultivars from southern China were analyzed with the Richards’ growth equation,as well as the leaf photosynthesis and chlorophyll fluorescence characteristics at late growth stage.Hybrid rice combination Xiuyou 5 showed slightly lower initial grain filling potential,maximum grain filling rate and mean grain filling rate than the conventional rice cultivar Xiushui 110,but longer active grain filling duration,contributing to get heavier grain weight and to cut down the competition for assimilate among grains per panicle.The differences in leaf photosynthesis and chlorophyll fluorescence parameters were not significant between Xiuyou 5 and Xiushui 110 at 10 d after flowering.However,Xiuyou 5 had significantly higher leaf photosynthesis and chlorophyll fluorescence parameters than Xiushui 110 at 25 d after flowering,except for the unquenchable portion of fluorescence.It is suggested that maintaining higher leaf biomass production capacity at late grain filling stage is a very important physiological mechanism for late japonica hybrid rice,resulting in longer active grain filling duration,and finally a relative better grain filling,heavier grain weight and higher grain yield despite the larger number of spikelets per panicle.

Select

Effect of N,P and K Fertilizer Application on Rice Grain Yield in Red Paddy Soil LI Cheng-liang ,HE Yuan-qiu ,WANG Yan-ling ,LIU Xiao-li 2007, 21(2): 179-184 .  Abstract ( )   PDF (125KB) ( )   Changes of rice biomass(including grain and straw yields),yield-increasing effect of nutrient and paddy soil fertility were investigated in a long-term NPK fertilization experiment under a double-cropping system.The effects of N,P and K fertilization at different ratios on total rice biomass were ranked as follows:NPK>NP>PK>NK>CK.The yield-increasing effects of N,P and K on rice biomass were 41.2%-54.8%、66.3%-88.2% and 10.3%-10.9%,respectively.The coefficients of variance of yield-increasing effect on rice biomass for N,P and K were reversely varied with their yield-increasing effect.It illuminated that the higher the yield-increasing effect on rice biomass was,the better its stability was.Early rice was obviously better than later rice with respect to the yield-increasing effect and its stability.The application of N,P and K fertilizer could markedly enhance the concentration of soil organic matter and total N in soil.The phosphorus fertilization significantly increased the content of total P and available P in soil.The potassium fertilizer application enhanced the concentration of total K and exchangeable K content in soil,however,the output of rice biomass significantly reduced.In fact,the balance between input and output of K limited the changes of total K and exchangeable K content in soil.The application of N,P and K fertilizer discordantly affected soil pH value,the N fertilization(urea)decreased soil pH value,whereas the P fertilization(calcium magnesium phosphate)slowed the soil pH value decline.

Select

Effects of Nitrogen,Phosphorus and Zinc Supply Levels on Grain Phytic Acid Content and Its Correlation with Several Mineral Nutrients in Rice Grains ZHAO Ning-chun ,ZHANG Qi-fang ,CHENG Fang-min ,ZHOU Wei-jun 2007, 21(2): 185-190 .  Abstract ( )   PDF (78KB) ( )   Effects of N,P and Zn treatments during rice developmental stage on grain phytic acid and its association with several mineral nutrients were studied in a hydroponic experiment with four rice cultivars,including indica cultivar Xieqingzao(XQZ)and its low phytic acid mutant(HIPi1),and japonica cultivar Xiushui 110 and its low phytic acid mutant(HIPj1).The results showed that higher N,P and Zn supply generally resulted in lower grain phytic acid content compared to lower N,P and Zn supply at rice developmental stage,although their sensitivities to P and Zn treatments were dependent on genotypes;N,P and Zn supply had a considerable influence on mineral nutrients accumulation in rice grains,with high N and P supply enhancing Fe concentration,but decreasing Cu accumulation in rice grains,respectively.Compared with low Zn supply,relatively lower grain Fe concentration,but more grain K,Mg accumulation could be found for high Zn treatment;Grain phytic acid was positively correlated with K,Mg,Fe and Cu concentrations in rice grains,but negatively with grain Zn concentration among different solution treatments,despite of their statistically significance varying with cultivars.These implied that the micro-nutritional quality could be synchronously improved by low phytic acid mutation,if an appropriate cultivation method was applied to enhance K,Mg,Fe and Zn concentrations in rice grains.

Select

Effects of Fertilization Level on Panicle Temperature at Heading Stage of Rice ZHANG Bin ,ZHENG Jian-chu ,YANG Fei ,TIAN Yun-lu ,PENG Lan ,LI Ming-an ,BIAN Xin-min ,ZHANG Wei-jian 2007, 21(2): 191-196 .  Abstract ( )   PDF (80KB) ( )   In order to illuminate the ecological mechanisms of avoidance and resistance to heat injury of rice,a field experiment was conducted to study the effects of fertilization level on panicle temperature at the heading stage in two rice varieties with significant differences in canopy and population development from 2004 to 2005 in Yangzhou City,Jiangsu Province,China.It showed a changing trend similar to the atmospheric temperature with the highest temperature during 10:30 to 15:30.The average panicle temperature of three treatments(low,middle and high fertilization levels)in Yangdao 6 and Yangjing 9538 were 3.58℃ and 3.04℃ respectively lower than the atmospheric temperature.In addition,the discrepancy between air and panicle temperature at high and middle fertilization levels were 1.54℃ and 0.90℃ higher than that at the low fertilization level.The discrepancy between air and panicle temperature in Yangdao 6 was also 0.85℃ higher than that of Yangjing 9538 at the same fertilization level. The discrepancy between air and panicle temperature in the three treatments showed a negative relationship with the transmittance of panicle,but positive with total leaf area index(LAI),LAI above the panicle,biomass and number of culms and tillers.These results indicated that a good structure of rice canopy and population from optimized field management,e.g.reasonable fertilization level could decrease the panicle temperature,and increase the avoidance and resistance to heat injury.

Select

Effects of Recommended Zinc Application According to Soil Testing on Yield Components of Rice and Soil Available Nutrients WEI Yi-chang ,BAI You-lu ,YANG Li-ping ,LIN Chang-hua ,YAO Zheng ,LUO Guo-an ,SONG Wei ,ZHU Chun-mei 2007, 21(2): 197-202 .  Abstract ( )   PDF (43KB) ( )   The effects of recommended Zn fertilization rate according to the soil nutrient test on rice(Oryza sativa L.)yield components,soil available Zn and other nutrient contents were studied in the coastal Haifeng Farm in plot and field experiments by a systematic approach for soil nutrients status evaluation introduced from Agro Service International Inc(ASI).The number of panicles per square meter,grain number per panicle,1000-grain weight,and yield of rice increased significantly in Zn fertilizer applicated plots compared to the control plot.They were at their best at the recommended zinc application rate of 15 kg/hm2,with the yield showing an increase of 16.9%.In addition,Zn concentration in rice plants and grains increased with rising Zn application rate,but the duration to maturity decreased.Soil residual available Zn and NH4+ concentrations increased significantly,but soil residual available P,K,Ca,Mg concentrations decreased and other soil available nutrient(S,B,Cu,Fe,Mn)concentrations and soil organic matter content and pH remained unchanged with the increase of zinc application rate,and the residual available Zn concentration was 1.83 mg/L at the recommended zinc application rate,which was nontoxic to rice growth.Therefore,zinc application rate on the basis of soil ASI testing not only improve the rice yield components,but also cause no zinc pollution.

Select

Difference of Competition Responses Between Rice and Barnyardgrass with Different Seedling Emergence Time under Elevated Atmosphere CO2 SUN Fu-zhi ,ZHU Jian-guo ,ZENG Qing ,ZHU Chun-wu ,ZHU Yun-zhi ,MA Hong-liang ,XIE Zu-bin ,YU Liu-qing 2007, 21(2): 203-208 .  Abstract ( )   PDF (153KB) ( )   Difference in responses to the competitions between rice and barnyardgrass with different seedling emergence time under FACE(Free-air CO2 enrichment)was studied by the field experiments.Under the FACE conditions,the tiller number,biomass and yield of rice increased,while those of the weed decreased.The ratios of aboveground biomass,tiller number and yields of rice and barnyardgrass in transplanting paddy field were increased significantly.The competitiveness of rice was enhanced relatively,while that of weed was weakened.The changing trends of the competitive relation were similar to the foregoing statement between rice and barnyardgrass in nursery beds at the vegetative growth stage,while the alteration was not significant at the reproductive stage.The yield and the biomass of rice competing with barnyardgrass generated from nursery beds increased 22.7% and 8.2% in the end,while those of barnyardgrass increased 9.5% and 11.9%,respectively.The ratios of aboveground biomass,tiller number and yield did not increase significantly.It was suggested that the responses to competition between rice and barnyardgrass under FACE were influenced by barnyardgrass emergence time.

Select

Response of Aquatic Alternanthera philoxeroides to Environmental Factors and Its Competition with Rice YU Liu-qing ,Yoshiharu FUJII ,ZHOU Yong-jun ,ZHANG Jian-ping ,LU Yong-liang ,XUAN Song-nan 2007, 21(2): 209-214 .  Abstract ( )   PDF (44KB) ( )   To determine the influence of the environmental factors on the viability of aquatic Alternanthera philoxeroides and its competitive ability against rice,the effects of low-temperature,drought stress,salt-alkali and water depth on the survival rate,propagation rate and fresh biomass of A.philoxeroides plants,and the influence of this weed with different population density on the rice grain yield were studied with bioassay method.The treatment with the stem of A.philoxeroides treated at 4℃ then grown under normal temperature gave A.philoxeroides a high viability of 84%,while no viable plants was found at-20℃.Compared with the fresh stem(with water content of 93.5%),the survival rate,propagated stem number and fresh biomass of A.philoxeroides stems at water content of 30.2% were reduced by 45%,33% and 74% respectively.The treatments of the 0.1% salt-alkaline solution led to the loss of the viability of A.philoxeroides stem.The A.philoxeroioles stem could grow in wet soil with different water depth.A.philoxeroides with a density of 23-360 plants/m2 reduced the rice grain yield by 43%-53% when the density of rice plants was 100 plants/m2.

研究简讯

Select

A Primer Design Method for Detection of Point Mutation in Rice QIU Fu-lin ,SHAO Guo-jun ,Hei LEUNG ,WU Jian-li ,CHENG Shi-hua 2007, 21(2): 215-219 .  Abstract ( )   PDF (1141KB) ( )   A primer design method was developed for detection of point mutation in rice.Twelve primer pairs were designed for detection of point mutation in 12 candidate genes.A single band was amplified successfully with each of 10 out of 12 primers(83%)from the genome and point mutations were detected in IR64 mutants as well.This method can be used for primer design for animals and other plant species also.In addition,common questions encountered in primer design were discussed and the corresponding measures were put forward.

研究简报

Select

A Model to Simulate High Temperature-Induced Sterility of Rice SHI Chun-lin ,JIN Zhi-qing ,TANG Ri-sheng ,ZHENG Jian-chu 2007, 21(2): 220-222 .  Abstract ( )   PDF (91KB) ( )   Temperature is one of the most important determinants for rice yield,particularly when a high temperature event occurs during flowering period.Under the background of global warming,frequent high temperature event during rice flowering period often leads to a higher sterility of rice.In order to quantify the effects of high temperature on the sterility of rice crops,the control experiments at different high temperature(35,37,39 and 41℃)and with various durations(1,3 and 5 d)in two cultivars were conducted during rice flowering period in 2004,and quantitative characteristics of rice flowering was cited from the literatures.The results showed that the daily probability density of flowering amount could be expressed as Possion distribution function,the daily fertility could be expressed in a quadratic equation,the flowering number in one day obeyed the normal distribution,and the relationship between temperature and spikelet fertility could be approximated by logistic curve.Based on the daily variation law of air temperature and the effect of high temperature on both opening and unopened spikelets,a model was developed to simulate high temperature-induced sterility.The model was validated with independent experimental data and the results showed that it could simulate the effects of high temperature on rice fertility well while temperature was below 40℃,and a larger error resulted from the excessive temperature(40℃)which would affect the fertility of those opened spikelets.Considering the daily maximal temperature over 40℃ is very few in open fields,the model developed is applicable for most of rice producing regions.