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101.
淡水驯化对桐花树光合生理特性的影响 总被引:5,自引:0,他引:5
以实验地全光照条件下淡水和人工海水培养种植的桐花树(Aegiceras corniculatum)幼苗为材料,采用Li 6400光合测定仪对不同月份桐花树幼苗的光合生理生态特性日动态进行测定,研究了桐花树的光合生理生态特性。结果表明:在7、10月份桐花树的净光合速率日变化呈双峰型,均出现“光合午休”现象。在7月份人工海水组和淡水组的最大净光合速率(Pmax)分别为9.97和11.95 μmol·m-2·s-1;而10月份的Pmax分别为12.2和12.9 μmol·m-2·s-1。而且淡水驯化下,桐花树的净光合速率较人工海水组高。由光响应曲线可知,桐花树人工海水组的最大净光合速率(Pmax)、光饱和点(LSP)、光补偿点(LCP)和表观量子效率(AQY)分别为7 μmol·m-2·s-1,1 477 μmol·m-2·s-1,30 μmol·m-2·s-1,0.031 3;而淡水组为8.69 μmol·m-2·s-1,980 μmol·m-2·s-1,40 μmol·m-2·s-1,0.011。在所测的生理生态因子中,光合有效辐射和气孔导度是影响桐花树光合作用最为强烈的因子,与桐花树的净光合速率和蒸腾速率均有极显著的相关关系(p<0.01)。试验说明淡水驯化的桐花树对光强的利用范围变窄,但有较高的净光合速率,表明桐花树对淡水环境具有较强的适应性。 相似文献
102.
Changxin Ma Yang Gao Guoliang Chai Hanxia Su Niejun Wang Yigang Yang Chunbo Li Di Miao Wei Wu 《遗传学报》2010,37(11):713-723
The freshwater planarian is a powerful animal model for studying regeneration and stem cell activity in vivo.During regeneration,stem ceils (neoblasts in planarian) migrated to the wounding edge to re-build missing parts of the body.However, proteins involved in regulating cell migration during planarian regeneration have not been studied extensively.Here we report two small GTPase genes (Djrho2 and Djrho3) of Dugesia japonica (strain Pek-1).In situ hybridization results indicated that Djrho2 was expressed throughout the body with the exception of the pharynx region while Djrho3 was specifically expressed along the gastro-vaseular system.Djrho2 was largely expressed in neoblasts since its expression was sensitive to X-ray irradiation.In Djrho2-RNAi planarians, smaller anterior blaste-mas were observed in tail fragments during regeneration.Consistently, defective regeneration of visual nerve was detected by immu-nostainning with VC-1 antibody.These results suggested that Djrho2 is required for proper anterior regeneration in planairan.In contrast,no abnormality was observed after RNAi of Djrho3.We compared protein compositions of control and Djrho2-RNAi planarians using an optimized proteomic approach.Twenty-two up-regulated and 26 de-regulated protein spots were observed in the two-dimensional elec-trophoresis gels, and 17 proteins were successfully identified by Mass Spectrometry (MS) analysis.Among them, 6 actin-binding or cy-toskeleton-related proteins were found de-expressed in Djrho2-RNAi animals, suggesting that abnormal cytoskeleton assembling and cell migration were likely reasons of defected regeneration. 相似文献
103.
A small scale expression screen identifies tissue specific markers in the Dugesia japonica strain Pek-1 总被引:1,自引:0,他引:1
Freshwater planaria has tremendous capacity to reform the missing part of the body and therefore is considered as one of the most important model organism for regeneration study.At present,Schmidtea mediterranea and Dugesia japonica are the two major species utilized for laboratory manipulations.Dugesia japonica flatworms are widely distributed in the Far East including Cherry Valley region in the north-west area of Beijing,China.We reported here the establishment of an asexual Dugesia japonica strain Pek-1,as a suitable system for regeneration study.Using morphological,karyotypical as well as phyiogenetic analyses,we confirmed that these flatworms indeed belonged to Dugesia japonica.We went on to show that the commonly used in situ probes and immunohistochemistry reagents and protocols were applicable to the Pek-1 strain.Using this strain,we carried out small scale analysis on EST,RNAi and gene expression.We identified 193 unique EST sequences and 65 of them had not been reported in planarian.By RNAi analysis,we showed that 48 genes,when down-regulated individually,had no effect on regeneration.Furthermore,we identified 3 groups of tissue specific expressing genes that were useful for cell lineage analysis.We concluded that the Dugesia japonica Pek-1 swain could be another suitable animal model to regeneration research. 相似文献
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108.
西藏多目涡虫属二新种记述(三肠目:淡水亚目:扁平涡虫科) 总被引:5,自引:1,他引:4
本文记述多目涡虫属二新种:林芝多目涡虫,新种Polycelis nyingchica sp.nov.和日喀则多目涡虫,新种Polycelis xigazensis sp.nov.。前者标本采自西藏林芝地区的林芝县和波密县;后者标本采自西藏山南地区浪卡子县,和日喀则地区江孜县,康马县,亚东县、拉孜县、定日县、聂拉木县等地。 相似文献
109.
温度对透明溞和隆线溞——亚种发育及生长的影响 总被引:13,自引:0,他引:13
透明溞(Daphnia hyalina)和隆线溞——亚种(D.carinata ssp.)的发育、生长与温度的关系极为密切。胚胎发育时间随温度升高而缩短。低温培养的个体普遍大于高温。龄期、寿命也随温度升高而变短。 相似文献