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101.

Purpose

Ornamentals can beautify the environment and resolve heavy metal pollution at the same time. Thus, the present study aimed at studying the growth and physiological response of Tagetes patula on iron ore tailings.

Materials and methods

Pot-culture experiments were conducted to investigate the effect of iron ore tailings both individually as well as in combination with soil (at different proportions) on the growth, pigment production as well as accumulation and translocation of various heavy metals from the tailings.

Results and discussion

The results suggested an increase in growth, chlorophyll content, as well as metal accumulation capacity of T. patula with increasing proportion of tailings in the soil. Furthermore, an increase in antioxidant activities in plants grown on tailings as compared to control was observed which suggests plant efficiency to overcome any stress generated due to excess of heavy metals. The order of accumulation of various heavy metals in the plant parts was observed to be Fe?>?Cr?>?Zn?>?Cu?>?Pb?>?Ni?>?Cd. Both bioaccumulation and translocation values were maximum for Fe and minimum for Ni and Cd, respectively.

Conclusions

The overall study clearly suggests plant ability to grow well on the tailings and survive excess of heavy metals present in the tailings. Thus, the plant qualifies well as a potential tool for phytostabilization of iron ore tailings and probably a source of income generation from wasteland owing to its multiple commercial values.  相似文献   
102.
The reactivity of different lectins with crude chromogranin A (CgA) obtained from different animals, namely, cow, horse, dog, pig, and dolphin, was examined to identify lectin(s) that would be useful as coating reagent(s) in a sandwich enzyme-linked immunosorbent assay (ELISA). Of the different lectins studied, the Amaranthus caudatus lectin (ACA), which is specific for the Thomsen-Friedenreich (T)-antigen (Galβ1-3GalNAc), was found to react with the CgA from different animals by western blotting. Purified rabbit anti-bovine CgA antibody was also found to cross-react with the crude CgA preparations. On the basis of these findings, a sandwich ELISA was developed with ACA as the coating reagent and anti-bovine CgA antibody as the probing antibody. Using this method, concentration-dependent curves ranging from 0.003 μg/mL to 25 μg/mL and from 0.02 μg/mL to 25 μg/mL were obtained for bovine CgA and canine CgA, respectively. Similarly, concentration-dependent curves were obtained for the equine, swine, and dolphin crude CgA extracts. Thus, ACA is concluded to be a valuable reagent for CgA detection in crude extracts from different animal species, and for CgA isolation/purification.  相似文献   
103.
Biochar is considered a potential technology to enhance chemical fertilizer use efficiency through intensification of the interactions between nutrients and the functional groups on biochar surfaces. However, little is known about how the application of activated biochars mixed with urea influences nitrogen(N) mineralization and crop performance in paddy fields. Here, a sawdust-derived fresh biochar (FBC)(ca. 400?C) was activated chemically with 15%hydrogen peroxide and biologically with a nutri...  相似文献   
104.
Abstract

Three eggplant (Solanum melongena L.) varieties – ‘Dafeng’, ‘Beisite’, and ‘Baiyu’ – were used in this experiment to discover the least susceptible variety among them to sweetpotato whitefly (Bemisia tabaci) infestation. The investigations were carried out after completing one generation of whitefly based on two points of view. Initially, host preference and suitability of whitefly was investigated based on adult feeding, oviposition, and developmental time. Therefore, it was investigated based on growth responses of eggplant. The average developmental time was shortest for the cohort reared in ‘Dafeng’ (21.3 days), while the longest period (23.2 days) was recorded in ‘Baiyu’. In comparison with the control, less significant changes in the six growth parameters, viz. plant height (12.6%), leaf area (12.7%), dry matter (8.2%), absolute growth rate (26.0%), relative growth rate (25.0%), and net assimilation rate (22.2%) were found in ‘Baiyu’ infested by B. tabaci. Adult attraction and oviposition were reduced while developmental time was increased in ‘Baiyu’ compared with the other two varieties. In addition, the reduction percentages of all the six plant-growth parameters of ‘Baiyu’ were comparatively less than other two varieties to whitefly stress. Our research is focused on a shorter development time; higher feeding, oviposition, and the reduction percentage of plant growth indicate that a plant is a suitable host. In view of this, the present findings indicate that ‘Baiyu’ is less susceptible than the other two varieties, ‘Dafeng’ and ‘Beisite’, for whitefly infestation.  相似文献   
105.
Effects of Al (0–100 μM) and Si (0–2,000 μM) supplied singly or in combination on root growth of different rice varieties were examined under hydroponic conditions. Al addition inhibited root elongation of rice plants, and the inhibition increased with increasing amount of Al in the culture solution. Among 22 indica varieties and among 8 japonica varieties tested, IAC3 and Nakateshinsenbon were relatively tolerant to AI, respectively, whereas IR45 and Norinl were relatively sensitive to AI, respectively. Si exerted a beneficial effect at all levels of Si treatment on indica varieties, whereas Si supply resulted in a slight increase in the root dry weight of japonica varieties only at the highest level (2,000 μM Silo The alleviation of Al inhibition of rice root growth by Si was observed in the combination of Al and Si treatments. Alleviation was more pronounced for all the Si treatments in indica varieties than in japonica varieties, and the alleviation was maximum with 2,000 μM Si in IR45. The alleviation effect by Si was more pronounced in the AI-sensitive varieties than in the AI-tolerant varieties. The application of Si resulted in an increase in the contents of Al and Si in plants, and there was no relationship between the Al content and Al inhibition in plants.  相似文献   
106.
Analysis of the effect of slow-releasing N fertilizers on microbial parameters of the rhizosphere soil is essential for their effective use. This investigation revealed the comparative effects of oxamide and ammonium sulfate as different N sources on some selected microbial parameters as well as the pH in the rhizosphere of wheat (Triticum aestivum cv. Nourin No. 61). The study was conducted on a Japanese upland alluvial soil using a rhizobox system. In the central compartment (CC) of the rhizoboxes treated with oxamide and ammonium sulfate, four wheat seedlings were grown for 53 d. In either of the treatments, the pH of the rhizosphere soil increased with the increase in the distance from the CC. In contrast, nitrate production, bacterial and fungal numbers, microbial biomass nitrogen, and β-acetylglucosaminidase activity decreased with the increase in the distance, with the highest values of the respective parameters being recorded in the CC. However, remarkable changes of these microbial parameters were found within a distance of 1–2 mm from the CC to the distant compartments. Thus the results indicated that pH, bacterial number, and nitrate production were high in the oxamide treatment. In contrast, higher fungal number, microbial biomass N, and .B-acetylglucosaminidase activity were associated with the ammonium sulfate treatment. It was assumed that the significant (p<O.05) effect of the rhizosphere on microbial activities varied with the treatments.  相似文献   
107.
The objectives of the present study were to investigate phytochemical screening and to assay cytotoxicity and antibacterial activities of ethanolic extracts of leaves of two medicinal plants, Aglaonema hookerianum Schott (Family: Araceae) and Lannea grandis Engl. (Family: Anacardiaceae) available in Bangladesh. The brine shrimp lethality bioassay showed that the ethanolic extracts of Aglaonema hookerianum and Lannea grandis possessed cytotoxic activities with LC50 5.25 (microg mL(-1)) and 5.75 (microg mL(-1)) and LC90 10.47 (microg mL(-1)) and 9.55 (microg mL(-1)), respectively. Two extracts obtained from leaves were examined for their antibacterial activities against some gram positive bacteria such as Bacillus subtilis, Bacillus megaterium and Staphylococcus aureus, also gram negative strains of Pseudomonas aeruginosa, Escherichia coli, Shigella dysenteriae, Salmonella typhi, Salmonella paratyphi and Vibrio cholerae. Agar disc diffusion method was applied to observe the antibacterial efficacy of the extracts. Results indicated that both plant extracts (500 microg disc(-1)) displayed antibacterial activity against all of the tested microorganisms. These results were also compared with the zones of inhibition produced by commercially available standard antibiotic, Amoxicillin at concentration of 10 microg disc(-1). Observed antibacterial properties of the ethanolic extract of Aglaonema hookerianum Schott and Lannea grandis Engl. showed that both plants might be useful sources for the development of new potent antibacterial agents.  相似文献   
108.
109.
半胱氨酸蛋白酶是蛋白质降解过程中的一类水解酶,参与植物的衰老与成熟,在植物生长发育过程中发挥重要作用。基于前期得到的小麦衰老阶段转录组数据中筛选到一个衰老特异的半胱氨酸蛋白酶(SAG39),为了研究TaSAG39基因在小麦衰老过程中发挥的作用,采用生物信息学分析方法和实时荧光定量(qRT-PCR)技术对TaSAG39的基因结构和表达模式进行分析。结果表明,其氨基酸序列与小麦祖先种节节麦、野生二粒小麦以及硬粒小麦亲缘关系最近,含有木瓜蛋白酶亚家族特有的活性位点Cys-His-Asn以及EFNIN结构。TaSAG39-5A、TaSAG39-5B、TaSAG39-5D基因组全长分别为1 455,1 435,1 439 bp,编码序列长分别为1 041,1 050,1 038 bp,均含2个外显子和1个内含子;其编码的蛋白分别由346,349,345个氨基酸组成,分子质量约37 ku,等电点5.53~5.67,为稳定的带负电的亲水性蛋白;主要构成元件为无规则卷曲和α-螺旋,在蛋白质N段含有信号肽,具有保守的Inhibitor_I29和Peptidase_C1结构域,含有35~37个磷酸化位点,...  相似文献   
110.
Severe acidifications in acid sulfate soils (ASSs) have occurred worldwide due to sulfuric acidity, which requires sustainable measures for their reclamation. Accordingly, an incubation study was conducted with the topsoil of two different ASSs (Cheringa and Badarkhali) to evaluate the effects of basic slag (BS; size <1 mm, pH 9.6, Ca 20.8%, Mg 9.8%, etc.), on reduction of acidity and changes in exchangeable cations. It is noted that BS is a byproduct of steel industry in Bangladesh and can be collected almost free of charge. These soils received BS at the rate of 0 (T0), 11 (T1), 22 (T2) and 33 (T3) t ha−1 under various moisture regimes (saturated condition M1,, i.e., 100% moisture content, wetting–drying cycles of 100 and 50% moisture M2, and moisture at field condition M3, i.e., 50%). The impacts of these treatments on some selected parameters in these soils were studied within 180 days of incubation. The application of BS was found to increase the pH of soils from 3.6 to 5.1 for Cheringa, 3.9 to 5.2 for Badarkhali soils at the end of incubation. These increments were more striking with the highest doses of BS under saturated moisture conditions in both of the soils. The ECe of the soils was not much influenced by the application of BS regardless of time. The treatments exerted significant (P ≤ 0.05) effects on exchangeable cations in different periods of incubation. The striking changes were recorded for the rate of increments of Ca2+ and Mg2+, which were about 2–3 times higher for Ca and more than 2 times higher for Mg2+ compared with the control after 180 days of incubation. These results suggest that the application of BS not only increased the Ca2+ to the higher amount than that of the increment of Mg2+ in the soils, but also improved one of the important criteria of Ca2+ and Mg2+ ratio in the soils.  相似文献   
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