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941.
942.
Jasmonic Acid Differentially Affects Growth, Ion Uptake and Abscisic Acid Concentration in Salt-tolerant and Salt-sensitive Rice Cultivars 总被引:2,自引:0,他引:2
D.-J. Kang Y.-J. Seo J.-D. Lee R. Ishii K. U. Kim D. H. Shin S. K. Park S. W. Jang I.-J. Lee 《Journal of Agronomy and Crop Science》2005,191(4):273-282
Phytohormones play critical roles in regulating plant responses to stress. Here, we investigated the effects of salt stress and stress recovery by applying jasmonate to the two different rice (Oryza sativa L.) cultivars Dongjinchalbyeo (DJC, salt-tolerant) and Dongjinbyeo (DJ, salt-sensitive). Salt stress remarkably decreased the root length of plants even at low NaCl concentration (20 mm ). Salt stress led to a sharp increase in the concentrations of abscisic acid (ABA) in 20 and 40 mm NaCl, when compared with the control values. The concentrations of ABA in the salt-tolerant cultivar DJC plants progressively increased with increasing NaCl levels, whereas in the salt-sensitive cultivar DJ, they sharply decreased in all three parts of rice plants at 80 mm NaCl treatment. The decrease of jasmonic acid (JA) concentrations in salt-tolerant cultivar DJC was lesser than in the salt-sensitive cultivar DJ plants in the shoot. Post-application in the stressed plants with 30 μm JA at 24 and 48 h after NaCl treatment, recovered salt inhibition on dry mass production more effectively than application of JA at 48 and 24 h before salt stress, and during salt stress simultaneously. The uptake of Na decreased especially in the salt-sensitive cultivar DJ plants, whereas there was an increase in Ca and Mg levels and slight increase of K by JA application. Leaf water potential, leaf photosynthetic rate, and maximum quantum yield of photosystem II (PSII) also remarkably recovered when 30 μm JA was applied 24 h after the salt stress compared with the 40 mm NaCl-treated plants. These results clearly indicate that post-application with exogenous JA can ameliorate salt-stressed rice seedlings, especially the salt-sensitive cultivar rather than the salt-tolerant cultivar. This may change the balance of other endogenous plant hormones. 相似文献
943.
离子注入诱发棉花过氧化物酶同功酶及农艺性状变异的研究 总被引:2,自引:0,他引:2
本文分析了氮离子注入处理棉花种子诱发M1植株第二真叶过氧化物酶同功酶(IPO)变异的遗传表现;M=IPO和农艺性状变异的频率及类型,探讨了剂量效应及IPO变异与农艺性状变异的关系。结果表明:M1IPO变异有些是非遗传的,M2中IPO不同酶带对氨离子注入的敏感性及最佳诱变剂量不同;氮离子注入能诱发较高频率的IPO变异及数量性状和多个性状的同时变异,可在较轻的M1损伤下获得较高的M2农艺性状变异频率,M2IPO和农艺性状变异频率与M1IPO变异频率的关系可用Y=A+BX+CX2来描述。在M2铃数和早熟性变异株中均可观察到第二真叶IPO第8条酶带,而铃重和株高变异株中可观察到第6条酶带。 相似文献
944.
945.
David A. Lightfoot Rajsree Mungur Rafiqa Ameziane Scott Nolte Lynn Long Karen Bernhard Andrew Colter Karen Jones M. J. Iqbal Edward Varsa Brian Young 《Euphytica》2007,156(1-2):103-116
Genetic modification of nitrogen metabolism via bacterial NADPH- dependent glutamate dehydrogenase (GDH; E.C.4.1.2.1) favorably
alters growth and metabolism of C3 plants. The aim of this study was to examine the effect of expression of GDH in the cytoplasmic
compartment of Zea mays cells. The gdhA gene from Escherichia coli , that encoded a NADPH-GDH, was ligated to the ubiquitin promoter that incorporated the first intron enhancer and used to
transform Z. mays cv. ‘H99’ embryo cultures by biolistics. R0–R3 generations included selfed inbreds, back-crossed inbreds, and hybrids with
B73 derivatives. The lines with the highest GDH specific activity produced infertile R0 plants. The highest specific activity
of GDH from the fertile Z. mays plants was sufficient to alter phenotypes. Plant damage caused by the phosphinothricin in gluphosinate-type herbicides, glutamine
synthetase (GS; EC 6.1.3.2) inhibitors, was less pronounced in Z. mays plants with gdhA pat than in gusA pat plants. Germination and grain biomass production were increased in gdhA transgenic plants in the field during seasons with significant water deficits but not over all locations. Water deficit
tolerance under controlled conditions was increased. Crops modified with gdhA may have value in semi-arid locations. 相似文献
946.
Profound hardening is the prerequisite for survival of a cultivar over winter. In the present study, hardening abilities of 13 winter wheat, 10 rye, 3 triticale and 6 winter barley cultivars were determined in field samples collected during the autumns of 1990 and 1991 by measuring the amount of ion leakage from frost-treated leaf segments. The cultivars tested were selected from the Inter-Nordic Winterhardiness Project, in which Field Survival Indices were determined for a total of 23 winter wheat, 13 rye, 5 triticale and 11 winter barley cultivars in order to estimate winter survival potentials under Finnish conditions. The winter survival of the materials studied correlated well with their hardening ability assessed by using the electrolyte leakage method. 相似文献
947.
Summary Plants of the salt-sensitiveL. esculentum, the halophytic wild speciesL. pennellii, their F1 hybrids and the interspecific F2 generation were grown in Hoagland's liquid culture containing 100 mM NaCl and 6 mM K+. Analysis of the Na+, Cl- and K+ ions contents of the leaves showed, as observed also in previous studies, that the cultivated parent accumlated more K+ and less Na+ than the wild parent. A total of 117 F2 plants were assayed for 15 electrophoretically detectable isozyme markers which map to nine of the twelve tomato chromosomes. Four loci, all with a similar quantitative effect on Na+ and Cl- uptake, were identified by virtue of their linkage to isozyme markers. Two other loci were found to affect K+ uptake. This study demonstrates the potential value of using genetic markers in order to gain a better understanding of the genetic basis of quantitative traits associated with the response of plants to salinity stress. 相似文献
948.
将柽柳(Tamarix sp.)金属硫蛋白基因(MT1,GenBank登录号:AB298390)插入植物表达载体pBI121,取代花椰菜病毒35S启动子下游的gus基因,利用农杆菌(Agrobactrium tumefaciens)介导法将MT1导入烟草(Nicotiana tobacum)基因组。对具有卡那霉素抗性,且经PCR-Southern检测和Northern杂交表现阳性的转基因株系进行抗Cd2+分析表明,金属硫蛋白基因的过量表达提高了转基因植株的抗Cd2+能力,在含200 µmol L-1和400 µmol L-1 Cd2+的MS培养基上,转基因植株的株高和鲜重均明显优于非转基因株系;在生理性状上表现为转基因植株MDA含量及POD活性明显低于非转基因株系,叶绿素含量和SOD活性比非转基因株系明显增加。 相似文献
949.
950.
辽宁设施栽培土壤盐分累积变化规律研究 总被引:13,自引:1,他引:13
对辽宁省主要设施栽培地区土壤盐分累积变化规律的凋查研究结果表明:(1)设施栽培土壤盐分含量和电导率较露地土壤有明显增加,且变化幅度较大,是露地的2.0~6.0倍。沈阳、北宁两地设施土壤的盐分含量分别为1347.48mg/kg(CV=59.3%),1274.25mg/kg(CV=40.5%)。(2)设施土壤连续种植到4年左右为盐分累积的高峰期,此时土壤的平均含盐量为1861.28mg/kg,EC值为0.53mS/cm,已超过所种作物的生育障碍临界点(EC〉0.5mS/cm)。此后,盐分含量因设施使用率的降低及采取的相关措施而有一定程度的降低。(3)设施土壤各盐分离子的含量均较露地土壤大大增加,盐分的累积以NO3^-、SO4^2-和Ca^2+的相对富集为主要特征。(4)盐分在设施土壤中的运移同时存在着向下迁移和向表层聚集两种方式,且以表聚为主。各盐分离子的含量随土层深度的增加而降低,NO3^-、CI^-、Ca^2+、Na^+的累积迁移量较大,在0~100cm各土层内的含量都高于对应露地层次,其中,硝酸盐的大量累积和向下迁移势必对环境造成不利影响。 相似文献