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Abstract: Combined use of chloropicrin (Pic) and 1,3-dicloropropene (1,3-D) is as effective as methyl bromide (MB) at controlling soilborne diseases in many trials and commercial uses. However, Pic and 1,3-D are both highly volatile and may pose strong exposure risks to humans and the environment. A gelatin capsule formulation containing Pic and 1,3-D has been developed to reduce exposure risks to workers and bystanders and improved application safety. We conducted two experiments in tomato and cucumber greenhouses located in Beijing and Qingdao, China, to study the efficacy of Pic plus 1,3-D gelatin capsules applied at different dosages and soil depths. Results indicated that both injection and gelatin capsules of Pic plus 1,3-D provided good control of soil nematodes and reduced disease index of Fusarium wilt and root-knot nematode. Plant yield of tomato and cucumber treated with gelatin capsules was similar to MB treatment. Based on our results, gelatin capsules applied at a soil depth of 15 cm provided better control of soilborne diseases and led to higher fruit yield compared to an application depth of 5 cm. In conclusion, a gelatin capsule of Pic plus 1,3-D is a promising and novel formulation, which not only shows good efficacy in controlling soilborne diseases, but also reduces potential exposure risks of fumigants.

One new flavonoid, 5,7,8,4′-tetrahydroxy-3-methoxyflavone-8-O-β-d-xylopyranoside (2), along with other four known flavones (1, 3–5) were isolated from the aerial parts of Solanum rostratum. 8-hydroxyflavonoid was isolated from series Androceras for the first time. The structure of the new compound 2 was determined on the basis of spectroscopic techniques, including IR, NMR and HRESI-MS. The chemotaxonomic significance of these compounds was summarised. [ABSTRACT FROM AUTHOR]

Background: To isolate plant-derived compounds with antimicrobial activity from the leaves of Mikania micrantha, to determine the compounds configuration, and to evaluate their antimicrobial activity against eight plant pathogenic fungi (Exserohilum turcicum, Colletotrichum lagenarium, Pseudoperonispora cubensis, Botrytis cirerea, Rhizoctonia solani, Phytophthora parasitica, Fusarium solani, and Pythium aphanidermatum,) and four plant pathogenic bacteria (gram negative bacteria: Ralstonia dolaanacearum, Xanthomonas oryzae pv. Oryzae, Xanthomonas Campestris pv. Vesicatoria, and Xanthomonas campestris pv. Citri), and four bacteria (gram positive bacteria: Staphyloccocus aureus, Bacillus subtilis, Micrococcus luteus, and Bacillus cereus). Methods and Results: Antimicrobial constituents of the leaves of M. micrantha were isolated using bioactivity- guided fractionation. The antifungal activity of the isolated compounds was evaluated by the inhibit hypha growth method and inhibit spore germination method. Characterization of antibacterial activity was carried out using the minimum inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs). MIC and MBC were determined by the broth microdilution method. Six compounds – deoxymikanolide, scandenolide, dihydroscandenolide, mikanolide, dihydromikanolide, and m - methoxy benzoic acid – have been isolated from leaves of Mikania micrantha H. B. K. Deoxymikanolide, scandenolide, and dihydroscandenolide were new compounds. The result of bioassay showed that all of isolated compounds were effective against tested strains and deoxymikanolide showed the strongest activity. Conclusions and Significance: The leaves of M. micrantha may be a promising source in the search for new antimicrobial drugs due to its efficacy and the broadest range. Meanwhile, adverse impact of M. micrantha will be eliminated. [ABSTRACT FROM AUTHOR]

To determine economic infestation level and economic threshold of Eupatorium adenophorum in pea-nut fields, additive series experiment and curve fit were adopted to study the changes of yield characteristics of pea-nut under different density of E. adenophorum in the fields. The results showed that with the interference of E. ade-nophorum, the peanut pods per plant, 100 - kernel weight and peanut kernel yield decreased gradually with the in-creasing weed density. The yield loss of peanut could be due to the decrease of peanut pods per plant and 100 -kernel weight. Moreover, the interference of light penetration rate and accumulation of nutrient and water in E. ade-nophorum may also cause yield loss of peanut. The power regression model (y = 1. 712x1. 063, P <0. 000 1 ) was rel-atively better in describing the relationship between E. adenophorum density (x) and yield loss (y) of peanut. The economic infestation levels for the E. adenophorum by manual weeding, glyphosate and picloram were 6. 06%, 0.57% and 0.77% respectively, and the economic thresholds were about 3.28, 0.36, and 0.46 plant • m-2 re-spectively. [ABSTRACT FROM AUTHOR]

The molecule of the title compound, C(12)H(8)ClF(3)N(4)O, is twisted as indicated by the C-O-C-C torsion angle of 76.9 (3)°. Moreover, the trifluoro-methyl group shows rotational disorder of the F atoms, with site-occupancy factors of 0.653 (6) and 0.347 (6). The dihedral angle between the rings is 1.88 (12) Å.