AGRICULTURE ECOSYSTEMS & ENVIRONMENT
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2017
·
IF 4.099
Congyan Wang,Jiawei Zhou,Jun Liu,Kun Jiang,Daolin Du
Soil N-fixing bacteria communities (SNB) can increase soil N availability, which can facilitate invasions of many kinds of invasive plant species. Meanwhile, variability in the forms of anthropogenic N deposition can mediate obvious shifts in both soil physicochemical properties and soil microbial communities (especially SNB). This can alter the soil micro-ecological mechanisms of plant invasions via changes in soil characteristics and soil microbial communities, especially SNB. This study uses next-generation high throughput sequencing technology to provide insight into the effects of invasion by Amaranthus retroflexus L. on the structure and diversity of SNB under different forms of simulated N deposition (SND). Soil pH under A. retroflexus invasion under various forms of SND was 8.08% lower than controls under a NH 4 -N treatment ( P < 0.05), 15.15% lower than controls under a NO 3 -N treatment ( P < 0.05), and 6.57% lower than controls under CO(NH 2 ) 2 -N and Mix-N treatments ( P < 0.05). Meanwhile, soil pH was one of the most important environmental variables explaining changes in the structure and diversity of SNB. The total number of species of SNB under A. retroflexus invasion was approximately 13.13% higher than controls for the NH 4 -N treatment ( P > 0.05), 11.00% higher than controls for the NO 3 -N treatment ( P > 0.05), 39.42% higher than controls for the CO(NH 2 ) 2 -N treatment ( P < 0.05), and 27.67 higher than controls for the Mix-N treatment ( P < 0.05). The positive effects mediated by the combined treatments of A. retroflexus invasion and SND may be ascribed to enhanced soil nutrient content (especially N), which can enhance the abundance of the nifH gene. The effects of A. retroflexus invasion on the total number of species of SNB under organic and mixed-N addition were greater than under inorganic N addition. This may be a consequence of a disturbance of the balance of inorganic to organic N for SND, as a result of the addition of a single form of inorganic N, which can diminish the stimulatory effects of soil nutrient content on SNB under inorganic N. Another potential cause of this pattern may be stronger acidification under inorganic N addition, which can exert more pronounced effects on SNB. LEfSe analysis showed that some species changed significantly under A. retroflexus invasion in the presence of SND (i.e., Rhodobacteraceae under NH 4 -N and Proteobacteria under CO(NH 2 ) 2 -N). Thus, A. retroflexus invasion in the presence of SND caused obvious shifts in certain species of SNB and increased the total number of species of SNB in particular, to facilitate its further invasion.
研究领域:
生态学
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微生物学
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产品关联
DOI
高影响因子
Journal of Integrative Agriculture
·
2022
·
IF 4.384
Hua-long YU,Ci TIAN,Rong-yan SHEN,Han Zhao,Juan YANG,Jin-gao DONG,Li-hui ZHANG,Shu-jie MA
Botanical herbicide has been a hot topic in the research and development of novel pesticides. The herbicidal activity and biochemical characteristics of the botanical compound drupacine were studied by evaluating its effects on seed germination, seedling growth, morphological and physiological characteristics of Amaranthus retroflexus . Drupacine inhibited seed germination and seedling growth, and had a median inhibition concentration (IC 50 ) value of 38.99 mg L −1 against A . retroflexus root. The α-amylase activity and soluble sugar content in treated plants were significantly lower than that of the control. The expression of α-amylase gene was dosage-dependently inhibited compared to the untreated control. This suggested that inhibition of α-amylase activity was a mode of action on seed germination. The root hairs were significantly decreased and part of the root cap fell off after treatment with drupacine. The ultrastructure observation showed that cell damage of root tips increased with the treatment time. Drupacine also increased the relative conductivity and malondialdehyde (MDA) content. Peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD) activities were significantly enhanced in the treatment compared to the control. These findings indicated that the physiological and biochemical reaction changes leading to morphological and membrane injuries were the main effects of drupacine on the inhibition of seedling growth. Drupacine can be developed as a botanical herbicide.
研究领域:
植物学
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农药科学
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植物生理学
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生物化学
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产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2018
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IF 3.849
Shujie Ma,Leilei Fu,Siqi He,Xiaopeng Lu,Yuanyong Wu,Zhiqing Ma,Xing Zhang
The evaluation of herbicidal activity and the isolation of plant allelopathic substances can lead to the discovery of new herbicide. This study has confirmed that the ethanol extract of S. mukorossi leaves was inhibitory to growth of Avena fatua L. and Amaranthus retroflexus L. both in petri dish experiment and pot culture assay, with the fresh weight inhibition varied between 47.60% and 62.05% at a concentration of 40 g/L of the leaf extract, being comparable to that of a commercialized natural product herbicide pelargonic acid at a concentration of 4 g/L. Five herbicidal compounds, oleanolic acid (1) , lupeol (2) , d-pinitol (3) , hexadecanoic acid (4) and octadecanoic acid (5) were isolated from the most active fraction, petroleum ether extract. D-pinitol (3) showed the highest growth inhibitory activity against both the shoot and root of A. fatua , with the half maximal inhibitory concentration (IC 50 ) values of 53.61 and 56.43 μg/mL, respectively. Furthermore, oleanolic acid (1) and d-pinitol (3) also inhibited the growth of A. retroflexus with the IC 50 value of 56.05 and 61.89 μg/mL against shoot growth, and 58.07 and 66.70 μg/mL against root growth, respectively. Thus, oleanolic acid (1) and d-pinitol (3) are the main phytotoxin constituents of S. mukorossi , and these compounds have the potential for further development as a botanical herbicide.
研究领域:
植物生理学
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化感作用
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天然产物化学
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杂草科学
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农药学
✓ 已验证
DOI
高影响因子
Nitrogen
·
2026
·Vol. 7
·期 2
·57
·
IF 2.8
Fan Yang,Yige Zhang,Wenhui Wang,Lu Xu,Jiayu Zhang,Jing Cao
Nitrogen forms and native plant traits jointly regulate the competitive ability of invasive plants. This study investigated the invasive speciesAmaranthus retroflexusand the native speciesPortulaca oleraceaandMedicago sativa. Using a pot experiment, we analyzed their competitive effects under NO3−-N, NH4+-N, CO(NH2)2-N and mixed nitrogen (Mix-N) treatments. The results showed that nitrogen addition had no significant effect on the relative yield ofA. retroflexusbut significantly increased the relative yield ofP. oleracea, thereby weakening the competitive advantage ofA. retroflexus. In contrast, nitrogen addition had no significant effect on the relative yield ofM. sativabut significantly increased the relative yield ofA. retroflexus, thereby enhancing the competitive advantage ofA. retroflexus. The effect of NO3−-N treatment varied markedly between the two mixed-culture systems: it strengthened the advantage ofA. retroflexuswhen grown withM. sativayet weakened the advantage when grown withP. oleracea. Further analysis revealed that the competitive advantage ofA. retroflexuswas associated with the optimization of its photosynthetic traits and nitrogen absorption efficiency. Specifically, it included greater leaf number, leaf area, SPAD value, and leaf biomass. In summary, the competitive performance of invasive plants is not a fixed attribute but rather a dynamic outcome jointly regulated by the interplay between native plant traits and soil nitrogen forms. This provides new insight into the invasion mechanism of alien plants and aids in formulating targeted control strategies.
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DOI
高影响因子
危险品化学品经营许可证（带存储）