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资助项目
0.05). For some populations, germination capacity in 12-h photoperiod was significantly higher than that in completed darkness（W-FD: P < 0.01, W-JD: P < 0.05）.Genetic variation within and among six populations was assessed using AFLP markers. Genetic diversity was higher at species level (PPL = 69.19%, HE = 0.221) than at population level (PPL = 26.22%, HE = 0.095, Is =0.140), and populations in southeast Yunnan were strongly differentiated from those in southwest Yunnan (Nei’s GST = 0.575; FST = 0.655). UPGMA analysis demonstrated a clear genetic division between the two populations from DeHong (SW Yunnan; D-JD and D-HG) and the four from WenShan (SE Yunnan; W-FD, W-LH, W-ML, and W-MG). Within-population genetic variation was significantly correlated with population isolation (r(PPL) = -0.94, P = 0.006; r(HE) = -0.85, P = 0.032; r(Is) = -0.87, P = 0.025), but not with population size (r(PPL) = 0.63, P = 0.178; r(HE) = 0.54, P = 0.268; r(Is) = 0.56, P = 0.249).","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&query1=LIGHT%2BENERGY&&fq=dc.project.title_filter%3ACraigia%5C+yunnanensis%5C+W.%5C+W.%5C+Smith%5C+%5C%26%5C+W.%5C+E.%5C+Evans%5C+%5C%28Tiliaceae%5C%29%5C+is%5C+an%5C+endangered%5C+deciduous%5C+tree%5C+species%5C+which%5C+has%5C+high%5C+scientific%5C+and%5C+economic%5C+value.%5C+C.%5C+yunnanensis%5C+is%5C+seriously%5C+threatened%5C+and%5C+has%5C+been%5C+pushed%5C+to%5C+the%5C+verge%5C+of%5C+extinction%5C+due%5C+to%5C+vegetation%5C+destruction%5C+in%5C+China%5C+and%5C+consequent%5C+contraction%5C+of%5C+its%5C+distribution.%5C+Hence%2C%5C+it%5C+was%5C+listed%5C+as%5C+a%5C+nationally%5C+rare%5C+and%5C+endangered%5C+plant%5C+in%5C+1999%5C+and%5C+has%5C+also%5C+been%5C+proposed%5C+as%5C+a%5C+second%5C-ranked%5C+plant%5C+for%5C+national%5C+protection%5C+in%5C+China%5C+and%5C+included%5C+in%5C+IUCN%5C+red%5C+list.%5C+As%5C+a%5C+scientifically%5C+important%5C+and%5C+valued%5C+tree%5C+species%5C+with%5C+endangered%5C+status%2C%5C+the%5C+wild%5C+populations%5C+of%5C+C.%5C+yunnanensis%5C+therefore%5C+represent%5C+is%5C+a%5C+genetic%5C+resource%5C+that%5C+must%5C+be%5C+conserved.%5C+To%5C+provide%5C+basic%5C+information%5C+for%5C+its%5C+conservation%2C%5C+the%5C+population%5C+dynamics%5C+and%5C+population%5C+size%5C+structures%2C%5C+pollination%5C+biology%5C+and%5C+breeding%5C+system%2C%5C+eleven%5C+fitness%5C-related%5C+characters%5C+and%5C+the%5C+genetic%5C+variability%5C+based%5C+on%5C+AFLP%5C+were%5C+comprehensively%5C+studied.%5C+The%5C+main%5C+results%5C+are%5C+summarized%5C+as%5C+follows%5C%3A%5C+A%5C+total%5C+of%5C+six%5C+wild%5C+populations%5C+of%5C+C.%5C+yunnanensis%5C+were%5C+found%5C+in%5C+two%5C+disjunct%5C+regions%5C+of%5C+Yunnan%2C%5C+i.e.%5C+WenShan%5C+%5C%28SE%5C+Yunnan%5C%29%5C+and%5C+DeHong%5C+%5C%28SW%5C+Yunnan%5C%29%2C%5C+from%5C+2005%5C+to%5C+2007.%5C+Additionally%2C%5C+in%5C+all%5C+but%5C+one%5C+of%5C+the%5C+populations%5C+we%5C+detected%2C%5C+mature%5C+trees%5C+were%5C+felled%5C+between%5C+2005%5C+and%5C+2007%2C%5C+so%5C+destruction%5C+of%5C+most%5C+of%5C+these%5C+populations%5C+is%5C+ongoing.%5C+Across%5C+the%5C+six%5C+populations%5C+of%5C+extant%5C+C.%5C+yunnanensis%5C+found%5C+during%5C+our%5C+study%2C%5C+the%5C+total%5C+number%5C+of%5C+mature%5C+%5C%28reproductive%5C%29%5C+individuals%5C+detected%5C+was%5C+584%5C+in%5C+2007%EF%BC%8Cplus%5C+larger%5C+numbers%5C+of%5C+seedling%5C+and%5C+resprouts%5C+from%5C+cut%5C+trunks.%5C+The%5C+result%5C+of%5C+surveying%5C+Population%5C+structure%5C+showed%5C+that%5C+there%5C+are%5C+two%5C+regeneration%5C+types%5C+which%5C+are%5C+seedlings%5C+and%5C+sprouts.%5C+Seedlings%5C+occurred%5C+abundantly%5C+in%5C+gaps%5C+or%5C+open%5C+areas%5C+and%5C+the%5C+size%5C+class%5C+frequency%5C+distributions%5C+were%5C+often%5C+discontinuous%2C%5C+and%5C+the%5C+same%5C+general%5C+pattern%5C+occurred%5C+in%5C+all%5C+the%5C+investigated%5C+populations%5C+for%5C+juveniles%5C+and%5C+adults.%5C+The%5C+numbers%5C+of%5C+seed%5C-origin%5C+individuals%5C+did%5C+however%5C+decline%5C+sharply%5C+with%5C+increasing%5C+size%2C%5C+indicating%5C+a%5C+high%5C+mortality%5C+rate%5C+going%5C+from%5C+seedling%5C+to%5C+sapling%5C+stage%5C+may%5C+be%5C+a%5C+problem%5C+for%5C+this%5C+species.%5C+Additionally%2C%5C+the%5C+cash%5C+crop%5C+cultivation%5C+and%5C+logging%5C+seriously%5C+threaten%5C+the%5C+survival%5C+of%5C+the%5C+species.%5C+We%5C+conducted%5C+field%5C+observations%5C+and%5C+artificial%5C+pollination%5C+experiments%5C+on%5C+the%5C+floral%5C+biology%2C%5C+pollination%5C+process%5C+and%5C+breeding%5C+system%5C+of%5C+Craigia%5C+yunnanensis%5C+in%5C+Fadou%2C%5C+Xichou%5C+county%5C+of%5C+Yunnan%5C+province.%5C+The%5C+lifespan%5C+of%5C+a%5C+single%5C+hermaphrodite%5C+flower%5C+is%5C+approximately%5C+3%5C-4%5C+days.%5C+A%5C+cyme%5C+has%5C+2%5C-9%5C+flowered.%5C+The%5C+flowering%5C+period%5C+of%5C+an%5C+inflorescence%5C+is%5C+usually%5C+5%5C-14%5C+days.%5C+The%5C+flowers%5C+of%5C+C.%5C+yunnanensis%5C+were%5C+protandrous.%5C+The%5C+stamens%5C+were%5C+within%5C+petal%5C-like%5C+staminodes%5C+in%5C+the%5C+opening%5C+flowers%5C+until%5C+the%5C+flower%5C+withered.%5C+Without%5C+touchment%2C%5C+the%5C+bractlike%5C+staminodes%5C+can%E2%80%99t%5C+open.%5C+Self%5C-pollination%5C+was%5C+partially%5C+avoided%5C+by%5C+temporal%5C+and%5C+spatial%5C+isolation%5C+of%5C+male%5C+and%5C+female%5C+organs%5C+within%5C+the%5C+same%5C+flower.%5C+However%2C%5C+autogamous%5C+and%5C+geitonogamous%5C+pollination%5C+is%5C+unavoidable%5C+because%5C+of%5C+the%5C+large%5C+number%5C+of%5C+flowers%5C+on%5C+a%5C+single%5C+tree%5C+and%5C+the%5C+action%5C+of%5C+pollinators.%5C+The%5C+values%5C+of%5C+both%5C+OCI%5C+%5C%28%E2%89%A54%5C%29%5C+and%5C+P%5C%2FO%5C+%5C%281381%5C%29%5C+and%5C+the%5C+results%5C+of%5C+bagging%5C+tests%5C+indicated%5C+there%5C+was%5C+no%5C+apomixes%5C+in%5C+C.%5C+yunnanensis%5C+and%5C+the%5C+breeding%5C+system%5C+of%5C+the%5C+species%5C+was%5C+outcrossing%5C+with%5C+partial%5C+self%5C-compatibility%5C+and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Science Foundation[15-23242S]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&query1=LIGHT%2BENERGY&&fq=dc.project.title_filter%3ACzech%5C+Science%5C+Foundation%5C%5B15%5C-23242S%5C%5D"},{"jsname":"Czech Science Foundation[16-26369S]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&query1=LIGHT%2BENERGY&&fq=dc.project.title_filter%3ACzech%5C+Science%5C+Foundation%5C%5B16%5C-26369S%5C%5D"},{"jsname":"Dendrobium officinale is a valuable medicinal plants，mainly distributed in Yunnan, Guangxi and Anhui. It is necessary to understand the environmental adaptation for the effective acclimation and cultivation of this species. Up till now, there is little information on the ecophysiological adaptation of D. officinale, especially on the photosynthetic response to temperature. This paper investigated the response of photosynthesis and growth of D. officinale to temperature, and the stem polysaccharide content of D. officinale at different temperatures, in order to understand how growth temperature affect the growth and development of D. officinale and to determine the suitable temperature ranges and day-night temperature differences for the growth and development of D. officinale. The result are summarized as follows: 1. Temperature has a significant effect on the photosynthetic rate (Pn) of D. officinale, The light saturated photosynthesis at ambient CO2 concentration (Pmax) of the plants were highest at T-30/20. High photosynthetic rate at T-30/20 were related to a larger leaf area (LA) and the more balance between the maximum rate of electron transport and maximum rate of RuBP-mediated carboxylation. 2. Temperature also has a significant effect on the growth and polysaccharide content of D. officinale’s stem. The polysaccharide content of D. officinale at T-20/10 was significantly higher than at the other temperatures, but the stem length, stem node number, stem fresh weight and stem dry weight was the highest at T-30/20. 3. The utilization of solar energy were highest at T-30/15 temperature difference between day and night, it also has the highest content of chlorophyll, and respiration rate was lower, resulting in higher dry matter accumulation and accumulation of relatively higher polysaccharide content. 4. The polysaccharide content of D. officinale T-30/20 temperature difference between day and night was significantly higher than at the other temperatures, but the leaf area was smaller and chlorophyll content, stem length, node number, the average stem length, stem fresh weight and stem dry weight and other indicators are relatively low. 5. My thesis illuminated how temperature affect the growth and development of D. officinale. The suitable temperature ranges and day-night temperature differences for the growth of D. officinale are recommended as below: day temperature is 25℃ ~ 30 ℃, night temperature is 15℃ ~ 20℃, and day-night temperature difference should be maintained at 10℃ ~ 15℃.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&query1=LIGHT%2BENERGY&&fq=dc.project.title_filter%3ADendrobium%5C+officinale%5C+is%5C+a%5C+valuable%5C+medicinal%5C+plants%EF%BC%8Cmainly%5C+distributed%5C+in%5C+Yunnan%2C%5C+Guangxi%5C+and%5C+Anhui.%5C+It%5C+is%5C+necessary%5C+to%5C+understand%5C+the%5C+environmental%5C+adaptation%5C+for%5C+the%5C+effective%5C+acclimation%5C+and%5C+cultivation%5C+of%5C+this%5C+species.%5C+Up%5C+till%5C+now%2C%5C+there%5C+is%5C+little%5C+information%5C+on%5C+the%5C+ecophysiological%5C+adaptation%5C+of%5C+D.%5C+officinale%2C%5C+especially%5C+on%5C+the%5C+photosynthetic%5C+response%5C+to%5C+temperature.%5C+This%5C+paper%5C+investigated%5C+the%5C+response%5C+of%5C+photosynthesis%5C+and%5C+growth%5C+of%5C+D.%5C+officinale%5C+to%5C+temperature%2C%5C+and%5C+the%5C+stem%5C+polysaccharide%5C+content%5C+of%5C+D.%5C+officinale%5C+at%5C+different%5C+temperatures%2C%5C+in%5C+order%5C+to%5C+understand%5C+how%5C+growth%5C+temperature%5C+affect%5C+the%5C+growth%5C+and%5C+development%5C+of%5C+D.%5C+officinale%5C+and%5C+to%5C+determine%5C+the%5C+suitable%5C+temperature%5C+ranges%5C+and%5C+day%5C-night%5C+temperature%5C+differences%5C+for%5C+the%5C+growth%5C+and%5C+development%5C+of%5C+D.%5C+officinale.%5C+The%5C+result%5C+are%5C+summarized%5C+as%5C+follows%5C%3A%5C+1.%5C+Temperature%5C+has%5C+a%5C+significant%5C+effect%5C+on%5C+the%5C+photosynthetic%5C+rate%5C+%5C%28Pn%5C%29%5C+of%5C+D.%5C+officinale%2C%5C+The%5C+light%5C+saturated%5C+photosynthesis%5C+at%5C+ambient%5C+CO2%5C+concentration%5C+%5C%28Pmax%5C%29%5C+of%5C+the%5C+plants%5C+were%5C+highest%5C+at%5C+T%5C-30%5C%2F20.%5C+High%5C+photosynthetic%5C+rate%5C+at%5C+T%5C-30%5C%2F20%5C+were%5C+related%5C+to%5C+a%5C+larger%5C+leaf%5C+area%5C+%5C%28LA%5C%29%5C+and%5C+the%5C+more%5C+balance%5C+between%5C+the%5C+maximum%5C+rate%5C+of%5C+electron%5C+transport%5C+and%C2%A0maximum%5C+rate%5C+of%5C+RuBP%5C-mediated%5C+carboxylation.%5C+2.%5C+Temperature%5C+also%5C+has%5C+a%5C+significant%5C+effect%5C+on%5C+the%5C+growth%5C+and%5C+polysaccharide%5C+content%5C+of%5C+D.%5C+officinale%E2%80%99s%5C+stem.%5C+The%5C+polysaccharide%5C+content%5C+of%5C+D.%5C+officinale%5C+at%5C+T%5C-20%5C%2F10%5C+was%5C+significantly%5C+higher%5C+than%5C+at%5C+the%5C+other%5C+temperatures%2C%5C+but%5C+the%5C+stem%5C+length%2C%5C+stem%5C+node%5C+number%2C%5C+stem%5C+fresh%5C+weight%5C+and%5C+stem%5C+dry%5C+weight%5C+was%5C+the%5C+highest%5C+at%5C+T%5C-30%5C%2F20.%5C+3.%5C+The%5C+utilization%5C+of%5C+solar%5C+energy%5C+were%5C+highest%5C+at%5C+T%5C-30%5C%2F15%5C+temperature%5C+difference%5C+between%5C+day%5C+and%5C+night%2C%5C+it%5C+also%5C+has%5C+the%5C+highest%5C+content%5C+of%5C+chlorophyll%2C%5C+and%5C+respiration%5C+rate%5C+was%5C+lower%2C%5C+resulting%5C+in%5C+higher%5C+dry%5C+matter%5C+accumulation%5C+and%5C+accumulation%5C+of%5C+relatively%5C+higher%5C+polysaccharide%5C+content.%5C+4.%5C+The%5C+polysaccharide%5C+content%5C+of%5C+D.%5C+officinale%5C+T%5C-30%5C%2F20%5C+temperature%5C+difference%5C+between%5C+day%5C+and%5C+night%5C+was%5C+significantly%5C+higher%5C+than%5C+at%5C+the%5C+other%5C+temperatures%2C%5C+but%5C+the%5C+leaf%5C+area%5C+was%5C+smaller%5C+and%5C+chlorophyll%5C+content%2C%5C+stem%5C+length%2C%5C+node%5C+number%2C%5C+the%5C+average%5C+stem%5C+length%2C%5C+stem%5C+fresh%5C+weight%5C+and%5C+stem%5C+dry%5C+weight%5C+and%5C+other%5C+indicators%5C+are%5C+relatively%5C+low.%5C+5.%5C+My%5C+thesis%5C+illuminated%5C+how%5C+temperature%5C+affect%5C+the%5C+growth%5C+and%5C+development%5C+of%5C+D.%5C+officinale.%5C+The%5C+suitable%5C+temperature%5C+ranges%5C+and%5C+day%5C-night%5C+temperature%5C+differences%5C+for%5C+the%5C+growth%5C+of%5C+D.%5C+officinale%5C+are%5C+recommended%5C+as%5C+below%5C%3A%5C+day%5C+temperature%5C+is%5C+25%E2%84%83%5C+%5C%7E%5C+30%5C+%E2%84%83%2C%5C+night%5C+temperature%5C+is%5C+15%E2%84%83%5C+%5C%7E%5C+20%E2%84%83%2C%5C+and%5C+day%5C-night%5C+temperature%5C+difference%5C+should%5C+be%5C+maintained%5C+at%5C+10%E2%84%83%5C+%5C%7E%5C+15%E2%84%83."},{"jsname":"Fundamental Research Funds for the Central Universities[17l-gzd24]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&query1=LIGHT%2BENERGY&&fq=dc.project.title_filter%3AFundamental%5C+Research%5C+Funds%5C+for%5C+the%5C+Central%5C+Universities%5C%5B17l%5C-gzd24%5C%5D"},{"jsname":"How has natural selection determined the evolution of gene regulation by acting on major regulatory factors? This question has been attractive to many evolutionary biologists for a long time. MicroRNAs (miRNAs) are endogenous posttranscriptional repressors and play essential roles in diverse biological processes in plants. To understand how natural selection has targeted on the entire lay of miRNA regulatory modules during flower development, we resequenced 31 miRNA target sites involved in flower development from five rice populations. We found that purifying selection serves as a major evolutionary force to act on the conserved miRNA binding sites, leading to the globally reduced genetic variation in highly conserved miRNA binding sequences within the entire rice samples. Conversely, positive selection allows variations at nonconserved miRNA binding sites and acts on them in a population-specific behaviour. Further analysis revealed that the polymorphisms within target sites may serve as raw materials for diverse functions of miRNAs by means of the destabilization of duplex, abolishment of existing target sites, and creation of novel ones. Together, the above-mentioned results indicate that variations at conserved binding sites are likely deleterious during rice flower development, whereas variants at nonconserved binding sites may be conductive to flower development-related phenotypic diversities and rice population adaption to variable environmental conditions as well. To further assess functional effects and evolutionary significance of variable alleles at the target genes, we reported the detailed characterization of the haplotype and linkage disequilibrium (LD) patterns of the entire target gene (LOC_Os01g18850，SPL 1) and the 1.4 Mb flanking regions in three rice populations, namely japonica, indica and O. rufipogon. The genetic profile of SNPs at target site and its flanking regions revealed high haplotype frequency, low haplotype diversity and strong LD in two cultivatedricepopulations. By contrast, we observed the opposite phenomena in O. rufipogon. Using the long-range haplotype (LRT) test, we found strong evidence of recent positive selection for SNP 3C/T alleles at target site in the combined O. sativa. Comparsion between the two rice subpopulations indicated that the major haplotype mh 2 containing SNP 3C accounts for half of all haplotypes in indica, while mh 3 containing SNP 3T is 91% in japonica. Moreover, the extent of LD is stronger in japonica than that in inidca. These differences suggest that independent evolutionary events may have occurred in target sequences of two cultivated rice populations and stronger positive selection acted on japonica. Next, we examined geographic distribution of polymorphic variants at target sites. We found that the major alleles SNP 3T and tightly linked SNP 4A in japonica appear to be associated with the adaption to the northern climates during rice flower development.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&query1=LIGHT%2BENERGY&&fq=dc.project.title_filter%3AHow%5C+has%5C+natural%5C+selection%5C+determined%5C+the%5C+evolution%5C+of%5C+gene%5C+regulation%5C+by%5C+acting%5C+on%5C+major%5C+regulatory%5C+factors%5C%3F%5C+This%5C+question%5C+has%5C+been%5C+attractive%5C+to%5C+many%5C+evolutionary%5C+biologists%5C+for%5C+a%5C+long%5C+time.%5C+MicroRNAs%5C+%5C%28miRNAs%5C%29%5C+are%5C+endogenous%5C+posttranscriptional%5C+repressors%5C+and%5C+play%5C+essential%5C+roles%5C+in%5C+diverse%5C+biological%5C+processes%5C+in%5C+plants.%5C+To%5C+understand%5C+how%5C+natural%5C+selection%5C+has%5C+targeted%5C+on%5C+the%5C+entire%5C+lay%5C+of%5C+miRNA%5C+regulatory%5C+modules%5C+during%5C+flower%5C+development%2C%5C+we%5C+resequenced%5C+31%5C+miRNA%5C+target%5C+sites%5C+involved%5C+in%5C+flower%5C+development%5C+from%5C+five%5C+rice%5C+populations.%5C+We%5C+found%5C+that%5C+purifying%5C+selection%5C+serves%5C+as%5C+a%5C+major%5C+evolutionary%5C+force%5C+to%5C+act%5C+on%5C+the%5C+conserved%5C+miRNA%5C+binding%5C+sites%2C%5C+leading%5C+to%5C+the%5C+globally%5C+reduced%5C+genetic%5C+variation%5C+in%5C+highly%5C+conserved%5C+miRNA%5C+binding%5C+sequences%5C+within%5C+the%5C+entire%5C+rice%5C+samples.%5C+Conversely%2C%5C+positive%5C+selection%5C+allows%5C+variations%5C+at%5C+nonconserved%5C+miRNA%5C+binding%5C+sites%5C+and%5C+acts%5C+on%5C+them%5C+in%5C+a%5C+population%5C-specific%5C+behaviour.%5C+Further%5C+analysis%5C+revealed%5C+that%5C+the%5C+polymorphisms%5C+within%5C+target%5C+sites%5C+may%5C+serve%5C+as%5C+raw%5C+materials%5C+for%5C+diverse%5C+functions%5C+of%5C+miRNAs%5C+by%5C+means%5C+of%5C+the%5C+destabilization%5C+of%5C+duplex%2C%5C+abolishment%5C+of%5C+existing%5C+target%5C+sites%2C%5C+and%5C+creation%5C+of%5C+novel%5C+ones.%5C+Together%2C%5C+the%5C+above%5C-mentioned%5C+results%5C+indicate%5C+that%5C+variations%5C+at%5C+conserved%5C+binding%5C+sites%5C+are%5C+likely%5C+deleterious%5C+during%5C+rice%5C+flower%5C+development%2C%5C+whereas%5C+variants%5C+at%5C+nonconserved%5C+binding%5C+sites%5C+may%5C+be%5C+conductive%5C+to%5C+flower%5C+development%5C-related%5C+phenotypic%5C+diversities%5C+and%5C+rice%5C+population%5C+adaption%5C+to%5C+variable%5C+environmental%5C+conditions%5C+as%5C+well.%5C+To%5C+further%5C+assess%5C+functional%5C+effects%5C+and%5C+evolutionary%5C+significance%5C+of%5C+variable%5C+alleles%5C+at%5C+the%5C+target%5C+genes%2C%5C+we%5C+reported%5C+the%5C+detailed%5C+characterization%5C+of%5C+the%5C+haplotype%5C+and%5C+linkage%5C+disequilibrium%5C+%5C%28LD%5C%29%5C+patterns%5C+of%5C+the%5C+entire%5C+target%5C+gene%5C+%5C%28LOC_Os01g18850%EF%BC%8CSPL%5C+1%5C%29%5C+and%5C+the%5C+1.4%5C+Mb%5C+flanking%5C+regions%5C+in%5C+three%5C+rice%5C+populations%2C%5C+namely%5C+japonica%2C%5C+indica%5C+and%5C+O.%5C+rufipogon.%5C+The%5C+genetic%5C+profile%5C+of%5C+SNPs%5C+at%5C+target%5C+site%5C+and%5C+its%5C+flanking%5C+regions%5C+revealed%5C+high%5C+haplotype%5C+frequency%2C%5C+low%5C+haplotype%5C+diversity%5C+and%5C+strong%5C+LD%5C+in%5C+two%5C+cultivatedricepopulations.%5C+By%5C+contrast%2C%5C+we%5C+observed%5C+the%5C+opposite%5C+phenomena%5C+in%5C+O.%5C+rufipogon.%5C+Using%5C+the%5C+long%5C-range%5C+haplotype%5C+%5C%28LRT%5C%29%5C+test%2C%5C+we%5C+found%5C+strong%5C+evidence%5C+of%5C+recent%5C+positive%5C+selection%5C+for%5C+SNP%5C+3C%5C%2FT%5C+alleles%5C+at%5C+target%5C+site%5C+in%5C+the%5C+combined%5C+O.%5C+sativa.%5C+Comparsion%5C+between%5C+the%5C+two%5C+rice%5C+subpopulations%5C+indicated%5C+that%5C+the%5C+major%5C+haplotype%5C+mh%5C+2%5C+containing%5C+SNP%5C+3C%5C+accounts%5C+for%5C+half%5C+of%5C+all%5C+haplotypes%5C+in%5C+indica%2C%5C+while%5C+mh%5C+3%5C+containing%5C+SNP%5C+3T%5C+is%5C+91%25%5C+in%5C+japonica.%5C+Moreover%2C%5C+the%5C+extent%5C+of%5C+LD%5C+is%5C+stronger%5C+in%5C+japonica%5C+than%5C+that%5C+in%5C+inidca.%5C+These%5C+differences%5C+suggest%5C+that%5C+independent%5C+evolutionary%5C+events%5C+may%5C+have%5C+occurred%5C+in%5C+target%5C+sequences%5C+of%5C+two%5C+cultivated%5C+rice%5C+populations%5C+and%5C+stronger%5C+positive%5C+selection%5C+acted%5C+on%5C+japonica.%5C+Next%2C%5C+we%5C+examined%5C+geographic%5C+distribution%5C+of%5C+polymorphic%5C+variants%5C+at%5C+target%5C+sites.%5C+We%5C+found%5C+that%5C+the%5C+major%5C+alleles%5C+SNP%5C+3T%5C+and%5C+tightly%5C+linked%5C+SNP%5C+4A%5C+in%5C+japonica%5C+appear%5C+to%5C+be%5C+associated%5C+with%5C+the%5C+adaption%5C+to%5C+the%5C+northern%5C+climates%5C+during%5C+rice%5C+flower%5C+development."},{"jsname":"ITC Research Fund from the Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, the Netherlands","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&query1=LIGHT%2BENERGY&&fq=dc.project.title_filter%3AITC%5C+Research%5C+Fund%5C+from%5C+the%5C+Faculty%5C+of%5C+Geo%5C-Information%5C+Science%5C+and%5C+Earth%5C+Observation%5C+%5C%28ITC%5C%29%2C%5C+University%5C+of%5C+Twente%2C%5C+the%5C+Netherlands"},{"jsname":"Key Research Program of Frontier Sciences, CAS[QYZDB-SSW-SMC051]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.date.issued.year&advanced=false&query1=LIGHT%2BENERGY&&fq=dc.project.title_filter%3AKey%5C+Research%5C+Program%5C+of%5C+Frontier%5C+Sciences%2C%5C+CAS%5C%5BQYZDB%5C-SSW%5C-SMC051%5C%5D"},{"jsname":"lastIndexed","jscount":"2024-09-26"}],"资助项目","dc.project.title_filter")'>
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