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191.
Pasquale Cascone Jozsef Vuts Michael A. Birkett Sarah Dewhirst Sergio Rasmann John A. Pickett Emilio Guerrieri 《Ecology letters》2023,26(3):460-469
While mechanisms of plant–plant communication for alerting neighbouring plants of an imminent insect herbivore attack have been described aboveground via the production of volatile organic compounds (VOCs), we are yet to decipher the specific components of plant–plant signalling belowground. Using bioassay-guided fractionation, we isolated and identified the non-protein amino acid l -DOPA, released from roots of Acyrtosiphon pisum aphid-infested Vicia faba plants, as an active compound in triggering the production of VOCs released aboveground in uninfested plants. In behavioural assays, we show that after contact with l -DOPA, healthy plants become highly attractive to the aphid parasitoid (Aphidius ervi), as if they were infested by aphids. We conclude that l -DOPA, originally described as a brain neurotransmitter precursor, can also enhance immunity in plants. 相似文献
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194.
Badreldin H. Ali Amal Ziada Isehaq Al HusseniSumyia Beegam Bader Al-RuqaishiAbderrahim Nemmar 《Phytomedicine》2011,18(13):1176-1180
Chronic renal failure (CRF) occurring naturally in patients or induced by subtotal nephrectomy in rats induces several alterations in the cardiovascular system (CVS). However, the effect of chemically induced CRF in rats on the CVS is less well known. We induced CRF in rats by feeding adenine (0.75%, w/w, four weeks) and investigated the effect of the ensuing CRF on the systolic and diastolic blood pressure (BP) and heart rate (HR). Further, we investigated the effect of giving acacia gum (AG, 10%, w/v) in the drinking water concomitantly with adenine on the above parameters. AG has been previously shown to ameliorate the severity of CRF in humans and rats. We confirmed here that adenine-induced CRF significantly increased the plasma concentrations of urea and creatinine, and reduced creatinine clearance. Additionally, it significantly increased both systolic and diastolic BP, with no significant effect on HR. Both of these actions were significantly mitigated by AG treatment. The antihypertensive angiotenisn-converting enzyme inhibitor lisinopril (10 mg/kg) was given by gavage to rats concomitantly with adenine, significantly reduced the rise in blood pressure induced by adenine. In conclusion, adenine-induced CRF in rats significantly increased BP, and this was significantly mitigated by administration of AG. Possible mechanisms of these changes and the protective effect of AG will be investigated. 相似文献
195.
The hatching of Heterodera glycines eggs in soybean root exudates collected after postemergence application of three herbicides, and the hatching potential of H. glycines eggs from females feeding on herbicide-treated plants, were measured in vitro. Hatching in all root exudate solutions (RES) was greater than in deionized water but less than in 0.003 M ZnSO₄ solution. Filtering RES with a 0.22-μm-filter increased H. glycines hatching in RES. Application of acifluorfen, bentazon, and lactofen to foliage of soybean plants inhibited hatching of H. glycines eggs from the same plants. Hatching in RES from the different herbicide-treated soybeans was similar. Application of crop oil concentrate and non-ionic surfactant adjuvant to foliage did not affect hatching of H. glycines eggs from soybean plants. 相似文献
196.
辣椒根系分泌的潜力化感物质对生菜幼苗抗氧化代谢的影响 总被引:3,自引:0,他引:3
以盆栽辣椒为试验材料,采用树脂吸附萃取和气质联用仪测定辣椒根系分泌物,分析、确定其中的疑似化感物质。分别使用6种(0、2、4、8、12、16μg·mL-1)不同浓度的外源潜力化感物质处理生菜种子,通过种子发芽、幼苗生长分析其潜力化感作用,并研究其对生菜幼苗抗氧化代谢的影响。结果表明,2,6-二叔丁基苯酚(2,6-DTBP)、邻苯二甲酸二异丁酯(DIBP)和邻苯二甲酸二丁酯(DBP)为辣椒根系分泌的潜力化感物质,随三种潜力化感物质浓度的增加,生菜幼苗的谷胱甘肽(GSH)含量降低,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)、多酚氧化酶(PPO)和抗坏血酸氧化酶(APx)活性先增加后降低。2,6.DTBP、DIBP和DBP4化感抑制作用的低限浓度分别为4、8、8pg·mL-1,三者通过降低GSH含量而损伤生菜幼苗的抗氧化代谢系统。 相似文献
197.
Root exudates of wetland plants influenced by nutrient status and types of plant cultivation 总被引:2,自引:0,他引:2
The present study investigated the amounts of root exudates and composition of organic acids released from two wetland plants (Typha latifolia and Vetiver zizanioides) under two nutrient treatments: low level (0.786 mM N and 0.032 mM P) and high level (7.86 mM N and 0.32 mM P) and two types of plant cultivation: monoculture and co-culture of the two plants. Low nutrient treatment significantly (p < 0.05) increased the root exudates of T. latifolia during the initial growth period (1-21 d) and those of V. zizanioides and the co-culture during the whole growth period. The concentrations of dissolved organic carbon in the root exudates of the co-culture in the low nutrient treatment were 3.23-7.91 times of those in the high nutrient treatment during the medium growth period (7-28 d). The compositions of organic acids varied between the two plant species and between the two nutrient treatments. The pattern of organic acids was also different between the co-culture and the monoculture. Oxalic acid was by far the major organic acid exuded from the two wetland plants. The present study on root exudates suggests that co-culture of wetland plant species would be more useful in the reclamation of waste water than a monoculture system. 相似文献
198.
199.
Germinating spores of Glomus intraradices can use internal and exogenous nitrogen sources for de novo biosynthesis of amino acids 总被引:1,自引:0,他引:1
200.
The stoichiometry of the redox reaction of caffeic acid with iron(III) was determined at pH 2.5. A linear increase in the
yield of iron(II) was found with increasing iron(III) concentration until reached constant values when iron(III)/caffeic acid
molar ratios were higher than 9. The reaction proceeds through two steps each having different rates, and involving intermediates
with different redox activities. A mechanism of the redox reaction consistent with our results is proposed. 相似文献