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In order to investigate the lethal dose of herbicide and its effect on physiological and biochemical characteristics of foxtail millet, in this study, three-leaf stage Jigu25 seedlings were treated with different concentrations of imazethapyr in seedling tray culture. The lethal dose of imazethapyr on Jigu25 seedlings was screened under different treatment concentrations and time. At the same time, the changes of chlorophyll content, electrolyte permeability, malondialdehyde(MDA) content, peroxidase(POD), superoxide dismutase(SOD) and catalase(CAT) activities of foxtail millet seedlings after imazethapyr treatment were measured. The results showed that the lethal dose of imazethapyr on Jigu25 seedlings was 3 375 mL/ha, and it was found that with the increase of herbicide concentration(2 250, 3 375, and 4 500 mL/ha) and the extension of treatment time, the corresponding physiological indexes of chlorophyll content, electrolyte permeability, MDA content, POD, SOD and CAT activities of Jigu25 seedlings showed significant changes at different time compared with the control. This study showed that after spraying a lethal dose of 3 375 mL/ha of imazethapyr, foxtail millet seedlings were subjected to stress and physiological protection mechanism was activated. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To explore the effects of imazethapyr on the physiological characteristics and yield components of imazethapyr-resistant and conventional foxtail millet varieties and the resistance mechanism, an imazethapyr-resistant variety Jigu35 and 7 conventional varieties Jigu38, Jigu41, Jingu21, Jingu59, Changnong44, Longgu39, and Zhonggu9 were used to compare the physiological characteristics and yield components in response to imazethapyr by pot and filed experiments. The results of the pot experiment showed that for conventional varieties, the aboveground fresh weight, the contents of chlorophyll a, chlorophyll b, carotenoid, and total chlorophyll in leaves were significantly decreased after active ingredient 93.5 g (a.i.)/hm² imazethapyr treatment by 21.60%-72.83%, 45.20%- 92.12%, 18.10%-93.36%, 42.58%-84.21%, and 45.73%-92.38%, respectively. The apparent photosynthetic electron transfer rate and maximum photochemical yield of chlorophyll fluorescence parameters decreased by 20.4%-37.0% and 6.9%-24.8%, respectively. The non-photochemical quenching coefficient and the quantum yield of regulatory energy dissipation significantly increased by 101.0%-322.1% and 113.7%-319.7%, respectively, while the imazethapyr-resistant variety Jigu35 were not changed significantly. The catalase (CAT) activity of Jigu35 was significantly increased by 52.48%, while it was decreased by 19.70%-56.58% for conventional foxtail millet varieties. The contents of malondialdehyde (MDA) of conventional varieties were significantly increased by 16.70%-68.80%, but had no significant effect on resistant variety Jigu35. The acetolactate synthase (ALS) activity of the resistant variety Jigu35 was slightly changed after the treatment of imazethapyr. The ALS activity of the conventional variety Jigu38, it was significantly decreased from the 13th day of treatment compared with the control. The field experiment showed that spraying imazethapyr at the seedling stage significantly reduced the ear length, ear diameter, ear weight, ear grain weight, and theoretical yield of conventional varieties. Different from conventional varieties, the ear weight, ear grain weight, and theoretical yield of resistant variety Jigu35 were significantly increased by 7.8%-8.6%. This indicated that the Jigu35 has a strong resistance to imazethapyr by maintaining the stability of ALS activity, increasing CAT activity, enhancing the removal of H2O2, and reducing the membrane lipid peroxidation. [ABSTRACT FROM AUTHOR]

To optimize the limitations of the exisiting fluorescent sensors: conventional single-emitting fluorescent sensors have limited sensitivity because the single emission can be easily affected by environmental factors, and the limited sensitivity and selectivity of dual/multiple-emitting fluorescent sensors because the internal energy transfer between lanthanide ions is susceptible to environmental factors like temperature. Two dual-emitting lanthanide metal-organic frameworks (Ln-MOFs) were utilized to achieve qualitative and quantitative detection of different pesticides simultaneously in water. Tb-MOF and Eu-MOF2 were synthesized, and their structures and properties were characterized. The prepared Ln-MOFs were used for qualitative and quantitative analysis of six pesticides (napropamide, picloram, imazethapyr, tebuconazole, flutriafol and benalaxyl). Combined with the UV-visible absorption spectra of each pesticide, the results showed that the energy transfer efficiency between Ln3+ and organic ligand in Ln-MOFs was regulated through interaction and competitive excitation energy absorption, and different pesticides had different effects on the energy transfer efficiency of organic ligand to Tb3+ and organic ligand to Eu3+. The values of lg(I545/I616) and lg(I545/I340) had a good linear relationship with the concentration, and R ² was above 0.97. This study provides a feasible strategy for developing a convenient, effective and universal ratiometric fluorescent sensor. [ABSTRACT FROM AUTHOR]

Shortawn foxtail (Alopecurus aequalis Sobol.) is one of the major malignant weeds infesting wheat (Triticum aestivum L.) fields with a rice (Oryza sativa L.) rotation across the middle and lower reaches of the Yangtze River in China. Mesosulfuron-methyl as an important herbicide is widely used for control of A. aequalis and other grass weeds in wheat fields. Previously, a suspected herbicideresistant A. aequalis population AHFT-01 was collected from a wheat field in Fengtai County, Anhui Province, China. To clarify its herbicide resistance status and potential resistance mechanisms, greenhouse pot experiments at the whole-plant level were performed to determine the susceptibility levels of AHFT-01 to mesosulfuron-methyl and several other acetolactate synthase (ALS) inhibitors. And different copies of the full-length ALS genes of the resistant and susceptible populations of A. aequalis were amplified, sequenced, and aligned. The results showed that compared with the susceptible population AHHN-02, A. aequalis population AHFT-01 was highly resistant to mesosulfuron-methyl with a resistance index (RI) of 28.50. ALS gene sequencing revealed that 100% of the plants of AHFT01 carried the homozygous Pro (CCC)-197-Thr (ACC) mutation in their ALS1 alleles. AHFT-01 plants also conferred different levels of cross-resistance to imazethapyr, pyroxsulam, and flucarbazonesodium, with RI values of 8.18, 10.15, and 10.13, respectively. In addition, AHFT-01 was lowly resistant to the acetyl-CoA carboxylase (ACCase) inhibitor pinoxaden but was susceptible to the other two ACCase inhibitors including fenoxaprop-P-ethyl and clethodim and the photosynthetic II (PSII) inhibitor isoproturon. This work indicates that the amino acid substitution at position 197 of ALS1 allele may be one of the important reasons that caused targe-site based resistance to mesosulfuron-methyl in A. aequalis. [ABSTRACT FROM AUTHOR]

Imidazolinone herbicides are widely used in China. Their advantages include wide herbicide spectrum, high activity and strong selectivity, but the pesticide remains in soil for a long time. In this paper, the effects of typical imidazolinone herbicides (imazamox, imazethapyr and imazapic) residues on succeeding crops, and investigated the microbial groups and degradation pathways of partially imidazolinone herbicides (imazamox, imazethapyr and imazapyr), the factors affecting the degradation of imidazolinone herbicides by microorganisms were analyzed. The existing problems and prospects for herbicide remediation were pointed out. It is helpful for the study on the microbial degraders of imidazolinone herbicides. [ABSTRACT FROM AUTHOR]

In order to explore the enzymes related to the degradation of imazethapyr by Serratia marcescens, the enzyme activities of urease, sucrase, catalase, polyphenol oxidase and cellulase in the culture medium of Serratia marcescens were detected by indophenol blue colorimetry, 3. 5 - dinitrosalicylic acid ( DNS) colorimetry, potassium permanganate titration and pyrogallol colorimetry, respectively. The pure culture medium without imazethapyr was used as control. The results showed that the urease activity of Serratia marcescens cultured with imazethapyr as the sole carbon source was the highest at the initial stage of culture, gradually decreased, and then tended to balance, and the sucrase activity increased slowly with the culture time. The activity of catalase showed a trend of increased - decreased - increased - decreased. The activity of polyphenol oxidase was the highest at the beginning of culture, and then decreased sharply to the lowest level after 72 hours. The cellulase activity decreased at first and then increased, and returned to the initial level at the end of culture. Through correlation analysis, it was found that the degradation rate of imazethapyr was highly negatively correlated with urease activity, highly correlated with sucrase activity. [ABSTRACT FROM AUTHOR]

In this paper, high - throughput sequencing was used to investigate the effects of the interactions between Trichoderma brevicompactum, soybean and imazethapyr on soil bacterial diversity and community structure. The soil without the above three substances was used as the negative control. The results showed that: five different treatment samples contained a total of 36 336 bacterial OTUs, of which 1 031 were bacterial species presented in all samples, accounting for only 2. 84% of the total bacteria. The bacterial diversity of soil samples under different treatments had changed, and the effect of T. brevicompactum and soybean on soil bacterial diversity was less than that of imazethapyr. The composition of the bacterial community structure was basically the same in different treatment samples, hut the relative abundance was very different. Proteobacteria was the dominant bacteria in five samples, with an average abundance of 50. 82%; at the genus level, Sphingomonas was the predominant bacterium in the five samples, followed by Gemmatimonas and Exiguobacterium. Conclusion: After adding T. brevicompactum to the soil, the soil bacterial diversity and total species decreased slightly; after planting soybeans, the soil bacterial diversity and total species increased; after adding imazethapyr, the soil bacterial diversity and total species decreased significantly; the effects of T. brevicompactum and soybean on soil bacterial diversity and total species were less than that of imazethapyr. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of Trichoderma brevicompactum and the interaction of Trichoderma brevicompactum, soybean and imazethapyr on the activities of sucrase and catalase in soil, 3. 5-dinitrosalicylic acid method and potassium permanganate titration were used to determine the activities of sucrose and catalase in soil respectively. The results showed that, when Trichoderma brevicompactum was added to the soil, in 5-20 days, sucrase activity showed a trend of activation with the highest activity of 53. 85 mg/kg in10 days and the activation rate of 169. 94%. Catalase activity showed a trend of activation-inhibition-recovery. The highest catalase activity was 2. 47 mg/g and the activation rate was 5. 71%. Then it was inhibited. The lowest catalase activity was 2. 30 mg/g and the highest inhibition rate was 17. 86%. After planting soybean, adding Trichoderma brevicompactum and 100 mg/kg imazethapyr, soil sucrose activity showed the trend of activation-recovery-activation-inhibition. The highest sucrase activity was 60. 09 mg/kg in 10 days, the activation rate was 201. 21%, and the sucrase activity was in habited in 20 days with the highest sucrase activity of 68. 12 mg/kg and the inhibition rate of 62. 43%. Soil catalase activity showed a trend of inhibition-recovery-activation, the lowest activity was 2. 43 mg/g in 20 days, the highest inhibition rate was 17. 98%, the highest activity was 2. 70 mg/g in 40 days, and the highest activation rate was 9. 46%. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simulated experiment was carried out to investigate the alexipharmic effect and mechanism of 1, 8 - naphthalic anhydride (NA) on the imazethapyr residues in soil using potted rape as bioassay material. The rape seedling height, fresh weight, activity of glutathione - S - transferase (GST), amount of amino acids, and content of glutathione (GSH) were reduced with 25g ai/hm² imazethapyr. The damage was alleviated under seed dressing with 0.5% (seed weight) NA. Compared tothe treatment of imazethapyr, rape seedling height and fresh weight were increased under NA + imazethapyr. The amount of amino acids, content of GSH, and activity of GSTs were induced by both NA and imazethapyr. Under NA + imazethapyr, 16 amino acids (except proline) were increased, GSH was slightly accumulated, while GST activity was significantly stimulated. Results indicated that imazethapyr detoxification was resulted from high amount of amino acid and more active GSTs. [ABSTRACT FROM AUTHOR]