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91.
Sajid Masood Muhammad Iqbal Hassan Javed Chaudhary M. Farooq Hussain Munis 《Journal of plant nutrition》2016,39(14):2100-2105
In this study, long-term effects of salinity and high boron (B) on subcellular distribution of sugars in wheat leaves were investigated. Four treatments with three replications of each; control, high B, sodium chloride (NaCl) and NaCl + high B, respectively were established according to completely randomized design. Plants were grown hydroponically and harvested after 6 weeks onset of experiment. NaCl treatment markedly decreased the shoot fresh and dry weight compared to high B or NaCl + high Boron. It increased the sugar concentrations in subcellular compartments, whereas decreased in NaCl + high B. Contrary, NaCl either alone or in combination with high B decreased the sugar contents in whole leaf compared to control or high B. Overall, higher concentrations of sugars were observed in symplast compared to apoplast indicating the symplast as major compartment for sugar transport. Furthermore, wheat plants accumulate sugars in subcellular compartments to maintain their growth under stress conditions. 相似文献
92.
铝胁迫对小麦根尖细胞蛋白质及苹果酸分泌的影响 总被引:10,自引:7,他引:10
以一对近等位基因小麦品系(ET8和ES8)为材料,研究了铝胁迫条件下根系生长情况,根尖铝含量,根尖细胞质蛋白组分以及铝胁迫下两个小麦品系苹果酸分泌的差异。结果表明,小麦品系ET8的耐铝性明显高于ES8;而ET8根尖铝含量则明显低于ES8;50mol/L铝处理24h后ES8小麦的细胞质蛋白组成受到明显影响,而ET8则无明显影响。由于铝胁迫条件下ET8分泌的苹果酸的量明显高于ES8,因此可以认为,分泌的苹果酸一方面与铝结合使其无毒化;另一方面将铝排斥于根尖细胞外,从而阻止铝进入细胞质内对细胞产生毒害作用。 相似文献
93.
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95.
Ute?FeilerEmail author Ilona?Kirchesch Peter?Heininger 《Journal of Soils and Sediments》2004,4(4):261-266
Background, Goal and Scope To date, standardised bioassays for the assessment of the ecotoxicological potential in sediments and dredged material use
test organisms like bacteria, algae and crustaceae. This paper presents the development and application of a novel sediment
contact test (whole sediment) withMyriophyllum aquaticum, a representative of rooted aquatic macrophytes. The aim of the present study is to demonstrate the value of a sediment contact
test with rooted macrophytes as a supplement to existing test batteries in order to improve the assessment of sediment toxicity.
Methods The newly developed sediment contact test withMyriophylhim aquaticum was applied to natural whole sediments. For performing the test, whorls ofMyriophyllum aquaticum were directly planted in the native sediment and incubated in the light at 24°C (cf. section results and discussion). The
end points of the test were the number of the shoots and the fresh weight of the whole plants. The duckweed growth inhibition
test withLemna minor according to ISO/DIS 20079 was performed in pore waters from sediment samples. The results of the sediment contact test withMyriophyllum aquaticum were compared with each other and with those of the aquatic duckweed test.
Results and Discussion A test protocol for the new plant-based sediment contact test using the aquatic plantMyriophyllum aquaticum as an indicator was developed. The best control sediment proved to be the OECD sediment (OECD 207). A test period of 10 days
appeared to be sufficient for the test. The increase of biomass and the derived growth rate were found to be the most suitable
evaluation parameters. The growth behaviour ofMyriophyllum aquaticum differed depending on the origin of sediments. Therefore, plant-affecting contamination, that is bound in sediments, was
indicated.
Conclusions The novel sediment contact test withMyriophyllum aquaticum can indicate phytotoxic effects in sediments. Therefore, it allows a better assessment of the overall-toxicity in whole sediments.
Recommendations and Outlook The sediment contact test withMyriophyllum aquaticum is a valuable tool for the evaluation of the ecotoxicological risk potential of waters and sediments. It should become a
complement to a standardised test battery generally used for the assessment of sediment toxicity. 相似文献
96.
小麦根尖细胞壁对铝的吸附/解吸特性及其与耐铝性的关系 总被引:6,自引:0,他引:6
研究了耐铝性明显差异的2个小麦基因型西矮麦1号(耐性)和辐84系(敏感)根系对铝毒胁迫的反应与根尖细胞壁组分以及细胞壁对铝的吸附和解吸的关系。结果表明,30mol/L.AlCl3可迅速抑制小麦根系伸长,但对辐84系根系伸长的抑制更为明显,且小麦根系相对伸长率随着铝浓度的提高而急剧降低。在30mol/L.AlCl3处理24h后,西矮麦1号根系伸长的抑制率为33.3%,而辐84系根系伸长的抑制率高达70.9%。小麦距根尖0~10.mm根段的铝含量和细胞壁中果胶糖醛酸含量显著高于10~20.mm根段,且前者对铝的累积吸附量明显大于后者;在0~10.mm根段,敏感基因型果胶含量高于耐性基因型,其根尖含铝量及根尖细胞壁对铝的吸附量都要大于后者。采用1.0.mol/L.NH3.H2O对细胞壁预处理2.h降低果胶甲基酯化程度后,耐性和敏感基因型根尖细胞壁对铝的累积吸附量分别降低了17.1%和20.9%,但对铝的累积解吸率没有影响。由此可见,小麦根尖是铝毒的主要位点,细胞壁果胶含量和果胶甲基酯化程度可能是导致不同小麦基因型根尖细胞壁对铝吸附量、铝积累量的差异及其对铝毒胁迫反应的差异的重要原因。 相似文献
97.
Renan Francisco Rimoldi Tavanti Grace David Queiroz Anne Caroline Da Rocha Silva Walmor Moya Peres Amanda Pereira Paixão Fernando Shintate Galindo 《Archives of Agronomy and Soil Science》2020,66(6):743-762
ABSTRACTThis study aimed to assess the physiological and biochemical responses of cotton plants to manganese (Mn2+) nutrition. Four cotton genotypes (G1 – TMG 47; G2 – FM 975 WS; G3 – TMG 11 WS and G4 – IMA 8405 GLT) were grown in nutrient solution under two Mn2+ concentrations (2 and 200 µmol L?1) for 10 days. No visible symptoms of Mn2+ toxicity were observed in the genotypes tested. All genotypes showed a marked increase in leaf chlorophylls, pheophytins, carotenoids, sucrose and total sugars concentration in response to high Mn2+ in a nutrient solution. However, the net photosynthetic rate, stomatal conductance, internal carbon dioxide concentration and transpiration decreased in genotypes G1 and G2 growing under 200 µmol L?1. Antioxidant enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) activities increased in genotypes G1, G3 and G4. Cotton genotypes showed an increased leaf antioxidant and sugar metabolism as a possible strategy to mitigate oxidative stress. The decrease in the net photosynthetic rate and stomatal conductance; the increased antioxidant enzymes activities (SOD, APX and GR); and the increase in leaf sucrose and total sugar concentration were the main physiological and biochemical responses in cotton plants to Mn2+ stress. 相似文献
98.
Common bean (Phaseolus vulgaris L.) proved to be very sensitive of low pH (4.3), with large genotypic differences in proton sensitivity. Therefore, proton toxicity did not allow the screening of common bean genotypes for aluminium (Al) resistance using the established protocol for maize (0.5 mM CaCl2, 8 μM H3BO3, pH 4.3). Increasing the pH to 4.5, the Ca2+ concentration to 5 mM, and addition of 0.5 mM KCl fully prevented proton toxicity in 28 tested genotypes and allowed to identify differences in Al resistance using the inhibition of root elongation by 20 μM Al supply for 36 h as parameter of Al injury. As in maize, Al treatment induced callose formation in root apices of common bean. Aluminium‐induced callose formation well reflected the effect of Ca supply on Al sensitivity as revealed by root‐growth inhibition. Aluminum‐induced callose formation in root apices of 28 bean genotypes differing in Al resistance after 36 h Al treatment was positively correlated to Al‐induced inhibition of root elongation and Al contents in the root apices. However, the relationship was less close than previously reported for maize. Also, after 12 h Al treatment, callose formation and Al contents in root apices did not reflect differences in Al resistance between two contrasting genotypes, indicating a different mode of the expression of Al toxicity and regulation of Al resistance in common bean than in maize. 相似文献
99.
噻虫嗪在农田土壤中环境行为的研究进展 总被引:2,自引:1,他引:2
噻虫嗪是当前全球销售量最大的新烟碱类农药之一,随着噻虫嗪的广泛使用,噻虫嗪在土壤环境中的迁移转化和归宿问题成为研究热点。本文总结了噻虫嗪对陆生生物(蜜蜂、蚕、蚯蚓、鹌鹑)、水生生物(藻类、大型溞、斑马鱼等)以及土壤微生物的影响,系统综述了噻虫嗪在农田土壤中的残留、降解、吸附解析以及迁移与淋溶等环境行为及主要影响因素,并指出了噻虫嗪在农田土壤中环境行为相关研究存在的不足以及未来研究应该关注的重点和方向,以期为噻虫嗪的科学安全使用以及保障农田土壤生态环境健康提供科学依据。 相似文献
100.
Ulrike Kammann Scarlett Biselli Ninja Reineke Werner Wosniok Dirk Danischewski Heinrich Hühnerfuss Angelika Kinder Arne Sierts-Herrmann Norbert Theobald Hans-Heinrich Vahl Michael Vobach Johannes Westendorf Hans Steinhart 《Journal of Soils and Sediments》2005,5(4):225-232