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Soil cadmium (Cd) causes toxicity and oxidative stress, alters biochemical processes and rootknot formation in rice. Irrigation of exogenous peroxidase (POX) together with its co-substrate H2O2(POXRice + H2O2), is likely to have protective effect upon the biochemical and nodular changes in ricegrown in Cd-rich soil. Exposure to Cd concentration of 1.00 mg/L increased oxidative stress, loss of cellviability, electrolyte leakage and root knot formation, whereas it significantly lowered the chlorophyll leveland rhizobium growth in rice. Irrigation of exogenous POXRice + H2O2 to Cd-stressed rice seedlingsreversed the Cd-induced alterations in rice to levels similar in control (non-stressed) seedlings. Resultsprovided strong evidence of exogenous POXRice + H2O2-mediated reversal and restoration of physiologicaland biochemical processes as well as increased resistance of rice seedlings to root knot formation.Irrigation with POXRice + H2O2 appeared to contribute towards bringing normoxic conditions in the otherwisehypoxic soil environment by enhancing the O2 in pot-experiments due to reduced Cd uptake, enhancedmineral homeostasis of essential elements viz. P, Fe, Mo, Mg and Mn for maintenance of root architecturedamaged by lipid peroxidation and reduction in oxidative stress by reducing Cd-induced reactive oxygenspecies generation. Therefore, the mitigation of Cd-toxicity in rice through this novel approach appeared tobe a promising mode to limit Cd-uptake, modulate protective and tolerance mechanisms for sustainablerice yield in Cd-contaminated rice-croplands and prevent nematode attack in rice, however, more detailedstudies are needed prior to large scale applications. 相似文献
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Nicolas P Mäder U Dervyn E Rochat T Leduc A Pigeonneau N Bidnenko E Marchadier E Hoebeke M Aymerich S Becher D Bisicchia P Botella E Delumeau O Doherty G Denham EL Fogg MJ Fromion V Goelzer A Hansen A Härtig E Harwood CR Homuth G Jarmer H Jules M Klipp E Le Chat L Lecointe F Lewis P Liebermeister W March A Mars RA Nannapaneni P Noone D Pohl S Rinn B Rügheimer F Sappa PK Samson F Schaffer M Schwikowski B Steil L Stülke J Wiegert T Devine KM Wilkinson AJ van Dijl JM Hecker M Völker U Bessières P 《Science (New York, N.Y.)》2012,335(6072):1103-1106
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Fusarium wilt (Fusarium oxysporum f. sp. ciceris) causes significant yield losses in chickpea worldwide. Faster, reliable and more specific molecular detection techniques were developed for the detection of Fusarium oxysporum f. sp. ciceris (Foc). The sequences obtained from multiple alignments of target genes, namely, translation elongation factor-1α (TEF-1α), β-tubulin, and internal transcribed spacer (ITS), were used to design Foc-specific markers/probes. One set of TEF-1α-based molecular marker, namely, SPα-F and R, two sets of β-tubulin-based markers, namely, SPβ1-F and R, and SPβ2-F and R, and one set of ITS gene, namely, SPT-F and R, were developed for the detection and quantification of Foc from diverse samples. The specificity and sensitivity of the designed molecular markers were evaluated through conventional and real-time PCR assays which differentiated the Foc from closely related species of Fusarium and other plant pathogens. In conventional PCR, the minimum detection limits of the markers ranged from 12.5 pg to 100 pg for genomic DNA of Foc and 0.5 ng to 10 ng for infected plant samples. In real-time PCR assay, the minimum detection limits of the markers ranged from 0.001 pg to 0.25 pg for genomic DNA of Foc and from 0.04 pg to 1.5 pg for the infected plant samples. Thus, the markers designed in the present study were found to be specific for Foc and can be used consistently for the detection and identification of Foc isolates. The probes developed from the two sets of markers, namely, SPα and SPβ2, also showed specificity with Foc. 相似文献
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环境高温条件下收获甘蔗酸性转化酶和葡聚糖蔗糖酶活性表现及其与糖分降低的关系 总被引：2，自引：0，他引：2
甘蔗收获后蔗糖分降低是蔗糖加工单位的主要问题之一,特别是那些在高温下持续压榨的地区。通过研究评估榨季后期甘蔗收获后蔗糖分的损失量及其与酸性转化酶和葡聚糖蔗糖酶活性的关系,结果表明,甘蔗收获后,随着这两种酶活性的上升,甘蔗的商品蔗糖急剧下降。刚收获的甘蔗商品蔗糖值为10．88,在收获48、240h后,则分别降低2．27、6．59个单位,10d后蔗糖分降低约60％。对收获的甘蔗淋水并覆盖蔗叶,其蔗糖分降低约44％,而经化学物质处理并覆盖蔗叶的甘蔗蔗糖分减少27％。在甘蔗贮放期间,其蔗糖酸性转化酶和葡聚糖蔗糖酶活性明显增加。经化学处理并覆盖蔗叶后,收获甘蔗的两种酶活性明显下降。研究结果还表明,通过应用抗菌和抗转化化学物质配方具有使后期收获的甘蔗蔗糖分降低到最小的可能性。 相似文献
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Samanthi Priyanka Withanage Md Aktar Hossain Sures Kumar M. Hairul Azman B Roslan Mohammad Puad Abdullah Suhaimi B. Napis Nor Aini Ab. Shukor 《Breeding Science》2015,65(3):177-191
Kenaf (Hibiscus cannabinus L.; Family: Malvaceae), is multipurpose crop, one of the potential alternatives of natural fiber for biocomposite materials. Longer fiber and higher cellulose contents are required for good quality biocomposite materials. However, average length of kenaf fiber (2.6 mm in bast and 1.28 mm in whole plant) is below the critical length (4 mm) for biocomposite production. Present study describes whether fiber length and cellulose content of kenaf plants could be enhanced by increasing GA biosynthesis in plants by overexpressing Arabidopsis thaliana Gibberellic Acid 20 oxidase (AtGA20ox) gene. AtGA20ox gene with intron was overexpressed in kenaf plants under the control of double CaMV 35S promoter, followed by in planta transformation into V36 and G4 varieties of kenaf. The lines with higher levels of bioactive GA (0.3–1.52 ng g−1 fresh weight) were further characterized for their morphological and biochemical traits including vegetative and reproductive growth, fiber dimension and chemical composition. Positive impact of increased gibberellins on biochemical composition, fiber dimension and their derivative values were demonstrated in some lines of transgenic kenaf including increased cellulose content (91%), fiber length and quality but it still requires further study to confirm the critical level of this particular bioactive GA in transgenic plants. 相似文献
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Journal of Crop Science and Biotechnology - Sesbania aculeata is an important legume crop used in agriculture, industries, as food, and traditional medicines. For its further genetic improvement,... 相似文献
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Journal of Plant Diseases and Protection - Plant diseases are the major factor behind production loss in agriculture. The traditional manual methods for disease detection in plants involve expert... 相似文献
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Priyanka Sahariah Vivek S. Gaware Ramona Lieder Sigríeur Jónsdóttir Martha á. Hjálmarsdóttir Olafur E. Sigurjonsson Már Másson 《Marine drugs》2014,12(8):4635-4658
A series of water-soluble cationic chitosan derivatives were prepared by chemoselective functionalization at the amino group of five different parent chitosans having varying degrees of acetylation and molecular weight. The quaternary moieties were introduced at different alkyl spacer lengths from the polymer backbone (C-0, C-2 and C-6) with the aid of 3,6-di-O-tert-butyldimethylsilyl protection of the chitosan backbone, thus allowing full (100%) substitution of the free amino groups. All of the derivatives were characterized using 1H-NMR, 1H-1H COSY and FT-IR spectroscopy, while molecular weight was determined by GPC. Antibacterial activity was investigated against Gram positive S. aureus and Gram negative E. coli. The relationship between structure and activity/toxicity was defined, considering the effect of the cationic group’s structure and its distance from the polymer backbone, as well as the degree of acetylation within a molecular weight range of 7–23 kDa for the final compounds. The N,N,N-trimethyl chitosan with 100% quaternization showed the highest antibacterial activity with moderate cytotoxicity, while increasing the spacer length reduced the activity. Trimethylammoniumyl quaternary ammonium moieties contributed more to activity than 1-pyridiniumyl moieties. In general, no trend in the antibacterial activity of the compounds with increasing molecular weight or degree of acetylation up to 34% was observed. 相似文献
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Withanage Prasadini Wasana Amal Senevirathne Chamilani Nikapitiya Tae-Yang Eom Youngdeuk Lee Jong-Soo Lee Do-Hyung Kang Chulhong Oh Mahanama De Zoysa 《Marine drugs》2021,19(12)
A marine bacterial strain was isolated from seawater and characterized for it beneficial probiotic effects using zebrafish as a model system. The strain was identified by morphological, physiological, biochemical, and phylogenetic analyses. The strain was most closely related to Pseudoalteromonas xiamenensis Y2, with 99.66% similarity; thus, we named it Pseudoalteromonas xiamenensis S1131. Improvement of host disease tolerance for the P. xiamenensis isolate was adapted in a zebrafish model using Edwardsiella piscicida challenge. The larvae were pre-exposed to P. xiamenensis prior to E. piscicida challenge, resulting in a 73.3% survival rate compared to a 46.6% survival for the control. The treated larvae tolerated elevated temperatures at 38 °C, with 85% survival, compared to 60% survival for the control. Assessment of immunomodulatory responses at the mRNA level demonstrated the suppression of pro-inflammatory markers tnfα and il6, and upregulation of heat shock protein hsp90 and mucin genes. The same effect was corroborated by immunoblot analysis, revealing significant inhibition of Tnfα and an enhanced expression of the Hsp90 protein. The antibacterial activity of P. xiamenensis may be related to mucin overexpression, which can suppress bacterial biofilm formation and enhance macrophage uptake. This phenomenon was evaluated using nonstimulated macrophage RAW264.7 cells. Further studies may be warranted to elucidate a complete profile of the probiotic effects, to expand the potential applications of the present P. xiamenensis isolate. 相似文献