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《Journal of plant nutrition》2013,36(10-11):2197-2210
Abstract The unicellular green alga Dunaliella was previously proposed as a model photosynthetic organism for adaptation to iron deficiency. The purpose of this study was to find out how iron limitation affects the structure and composition of the photosynthetic system of Dunaliella salina. Iron deprivation did not retard proliferation of D. salina cells, but was associated with a decrease in cell volume and chlorophyll content, and with a four‐fold reduction in iron content and a two‐fold increase in Cu content. Electron microscopic analysis revealed shrinkage of the chloroplast and decrease in stacked thylakoid membranes. Measurements of chlorophyll fluorescence induction in the presence of DCMU and of 77 K chlorophyll fluorescence emission spectra indicated gross changes in the photosynthetic efficiency of reaction centers and in the organization of their associated light harvesting antenna. Differential analysis of protein composition led to the identification of a major thylakoid membrane protein (Tidi), that was specifically induced under iron deprivation. Partial sequencing suggests that Tidi is a novel type of a chlorophyll a/b binding protein. These results clearly show that iron limitation is associated with extensive reorganization of the photosynthetic system in Dunaliella. 相似文献
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《Plant Production Science》2013,16(3):235-242
AbstractThe objective of this study was to clarify the effects of soil temperature in the stage from late tillering to panicle initiation (SI) and during the grain-filling stage (SII) on grain setting, dry matter production, photosynthesis, non-structural carbohydrate (NSC), xylem exudation and abscisic acid (ABA) levels in rice (Oryza sativa L. cv. Koshihikari). Rice plants were exposed to four different soil temperatures during SI or SII: 17.5, 25, 31.5 and 36.5°C (ST18, ST25, ST32 and ST37, respectively). The yield, yield components, grain filling and quality in SI were negatively influenced by high soil temperature of 37°C. On the other hand, there was no significant difference in those characters among temperature treatments in SII. The root/shoot ratio was smallest in the ST37 plants in both SI and SII, mainly due to their lighter root weight. At 7 days after initiation of treatment (DAT) in both SI and SII, the photosynthetic and xylem exudation rate tended to increase slightly as soil temperature increased up to 32°C. At 21 DAT, however, the photosynthetic rate was lowest in ST37, with concurrent decrease of diffusion conductance and SPAD value. In addition, decrease of NSC concentration in stem and xylem exudation rate, and increase of ABA level in leaves and xylem exudate were observed in ST37 plants at 21 DAT. These results suggested that high soil temperature before heading especially influenced yield, grain quality and plant growth. Possible mechanisms of the effect of soil temperature are discussed. 相似文献
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增施有机肥和微生物菌剂对春季杨凌设施番茄产量和品质的影响 总被引:3,自引:0,他引:3
为探究增施有机肥和微生物菌剂对春季设施栽培番茄光合作用、产量、品质及土壤肥料利用率的影响,以‘巴宝丽’番茄品种为试材,共设5个处理(不施肥,CK;施有机肥,T1;有机肥+复合肥,T2;增施30%有机肥+复合肥,T3;增施30%有机肥+复合肥+微生物菌剂,T4),分析不同处理对番茄植株光合、产量、品质及肥料利用率的影响。结果表明,与有机肥+复合肥处理相比,增施30%有机肥+复合肥处理使番茄增产21.69%,且显著提高番茄果实的可溶性蛋白和维生素C质量分数,土壤氮、磷和钾肥利用效率分别增加17.12%、11.82%和50.57%;增施30%有机肥+复合肥+微生物菌剂使番茄增产29.03%,果实可溶性总糖、维生素C、还原糖质量分数分别提高62.50%、21.30%和97.31%,土壤氮、磷和钾肥利用效率分别增加24.56%、18.73%和63.12%。研究认为增施有机肥(30%)和微生物菌剂可以增强土壤肥料利用率,促进番茄光合作用及干物质积累,最终提高果实产量和品质,建议在杨凌地区春季设施番茄的生产中使用。 相似文献
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为探索兰花内生真菌在兰科植物生长发育中的效用,以野生五唇兰中分离并初步筛选的内生菌根真菌为接菌剂,对五唇兰无菌组培苗进行菌根化苗盆栽试验,试验采用液体培养的菌液进行根部喷施,待菌根化苗生长18个月后测定其成活率及光合生理等指标。结果表明:接菌明显提高了五唇兰幼苗成活率,促进了光合速率(Pn)、气孔导度(Cond)、蒸腾速率(Tr)及叶绿素含量和叶面积的增加,并降低了胞间CO2浓度(Ci),以接dmf-49菌处理效果最明显,但五唇兰光合速率不高,在1.50μmol·m-2·s-1以下。表明从野生五唇兰中分离并初步筛选的有效内生真菌能提高其菌根化苗的光合能力,提高植株的生活力。 相似文献
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[目的】研究缺硼对黄瓜幼苗光合生理生化的影响。【方法]采用沙培法,以川绿1号为供试品种,研究缺硼对黄瓜幼苗的叶面积、光合速率、Rubisco酶活性、碳水化合物含量的影响。【结果]缺硼处理抑制了黄瓜幼苗的根、茎叶生物量的增加,增加了冠根比,减小了叶面积;在缺硼条件下,黄瓜幼苗叶片中的淀粉、可溶性糖、还原糖和总碳水化合物的含量增加,蔗糖含量降低;净光合速率明显降低,Rubiso酶活性和叶绿素a、b含量明显减少,而叶绿素a/b变化不明显。【结论】缺硼通过增加叶片中的碳水化合物,降低Rubisco酶活性,减少光合色素,进而降低光合速率来抑制黄瓜幼苗生长。 相似文献
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