Plant Protection Products (ppp_s) have been evaluated and authorised in the European Union (EU), in accordance with a harmonised regulatory system (Dir. 91/414/EEC), since 1993. Efficacy evaluation is an integral part of the EU regulatory system of registration of ppp_s (Dir. 91/414/EEC) and is the main subject of this review paper. The efficacy data requirements and evaluation principles are analyzed and discussed along with an outline presentation of the evaluation systems of the EU. The trials needed for the efficacy evaluation of plant protection products (ppp_s) across EU have to be conducted according to the principles of Good Experimental Practice by officially recognized testing facilities and in line with the methods specified by the Standards of the European and Mediterranean Plant Protection Organization. For registration purposes, the efficacy parameters which should be considered in the experimentation and evaluation of a ppp, according to EU criteria, are effectiveness (direct efficacy), resistance risk and the absence of undesirable effects on: a) plants or plant products (phytotoxicity, yield, quality), b) succeeding and adjacent crops, c) plants or plant products used for propagation, and d) beneficial arthropods. Efficacy and other desirable effects from the use of ppp_s have to be weighed against their potential phytotoxicity and/or other undesirable effects during the evaluation process. The evaluation of efficacy data of ppp_s, provided by the notifiers in the Biological Assessment Dossier, and the decision taken on authorization are performed across Member States on the basis of the “Uniform Principles” of the EU. Experience gained in implementing the provisions of Dir. 91/414/EEC has demonstrated that a number of changes are required. The main changes to this system, which are in progress, and also other systems on efficacy evaluation of ppp_s outside EU are discussed.

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Orysastrobin is a new QoI fungicide with excellent fungicidal efficacy against leaf and panicle blast and against sheath blight in rice. Formulations developed for seedling box treatments provide long lasting residual control combined with excellent plant selectivity under different environmental conditions. The sensitivity was monitored based on genetic assays. No samples with reduced sensitivity could be detected in our extensive monitoring studies in 2004 and 2005.

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Fluorinated non-ionic surfactants were assessed as adjuvants for tribenuron-methyl, triflusulfuron-methyl and foramsulfuron. The compared adjuvants included hydroxy-terminated fluorinated polyether (PF-151N), polyoxyethylene-alpha-fluoro-omega-(2-hydroxyethyl)poly(difluoromethylene) (Zonyl FSN-100), and polyoxyethylene(23) lauryl ether (Brij 35). Greenhouse experiments were performed to evaluate these surfactants both for their efficacy in controlling weeds and selectivity to crops. Tribenuron-methyl and triflusulfuron-methyl absorption into catchweed and giant foxtail leaves due to surfactant addition was also estimated. Zonyl FSN-100 and Brij 35 allowed a reduction in the application rate of triflusulfuron-methyl to nearly 1/2 of the labelled rate to control redroot pigweed. The foramsulfuron rate was reduced by more than 50% to control barnyardgrass thanks to the addition of Zonyl FSN-100 and it controlled giant foxtail only applied at the maximum labelled rate and mixed with Zonyl FSN-100. Tribenuron-methyl activity against poppy was only slightly enhanced by the use of adjuvants. Tribenuron-methyl efficacy was clearly enhanced by the use of adjuvants to control catchweed; however, the required dose was not lower than the labelled one. The addition of adjuvants induced slight phytotoxicity in the crops. Brij 35 caused the greatest absorption of triflusulfuron-methyl into giant foxtail leaves and of tribenuron-methyl into catchweed leaves.

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Total RNA samples were extracted from the non-photosynthetic root parasitic plants Orobanche minor and O. ramosa and used to synthesize cDNAs. The cDNA fragments encoding ethylene biosynthesis enzymes, 1-amino-1-cyclopropanecarboxylic acid (ACC) synthase and ACC oxidase, were amplified and characterized. ACC synthases (OmACS and OrACS) and ACC oxidases (OmACO and OrACO) were found to have high homologies with those in other plants, in particular, with SHACS2 and SHACO1 of the root hemiparasite Striga hermonthica. The expression of these genes after germination stimulation by (+)-strigol, a natural germination stimulant, was slightly increased in O. ramosa but not in O. minor, indicating the possible involvement of ethylene biosynthesis in the germination of O. ramosa. In these root parasites, however, inhibitors of ethylene biosynthesis and action did not affect seed germination elicited by (+)-strigol except for the ethylene action inhibitor silver thiosulfate in O. ramosa.

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A microarray containing PCR products from a large number of candidate genes in insecticide resistance was constructed. A total of 646 genes putatively involved in insecticide resistance and positive control genes were obtained from six insect species, Apis cerana, Blattella germanica, Spodoptera exigua, Musca domestica, Nilaparrata lugens and Culex pipiens. These genes represent cytochrome P450, ion channel, protective enzyme and other genes, which may play important roles in insecticide resistance. The optical microarray printing concentration (250 ng/μl) was determined using gradient concentration hybridization assay. The DNA microarray was then constructed with all target genes. A PCR probe composed of 18 target genes was prepared to validate the hybridization specificity of the microarray. The positive rate of this validation test was 83.3%. In addition, analysis of differential gene expression between susceptible and multi-resistant (cypermethrin and malathion) strains of M. domestica showed that 17 genes were over-expressed in the resistant strain. The results imply that cytochrome P450 genes, especially the genes of CYP4 and 6 families, play important roles in the resistance of M. domestica to both insecticides. The 17 genes validated by using qRT-PCR were found to have a similar tendency, mostly compared with using a microarray, indicating that this microarray is suitable for studying insecticide resistance.

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A series of O,O-dialkyl 1-(3-trifluoromethylphenoxyacetoxy)-1-substituted methylphosphonates were synthesized by the condensation of O,O-dialkyl 1-hydroxyalkylphosphonates with 3-trifluoromethylphenoxyacetyl chloride. Their herbicidal activity against a set of weed species was examined. The results showed that improvement of herbicidal activity required a reasonable combination of substituents in the parent structure, which provided some hints for further study of structure modification.

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Compounds of the 4-chlorophenethyl amine part of carpropamid were replaced with alkyl, cycloalkyl and substituted phenylalkyl amines. The amines were obtained from the corresponding ketoximes using a reduction system of sodium borohydride with molybdenum oxide as the additive.

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A series of ascaridole derivatives 1–10 were successfully synthesized and their structures were characterized by ¹H, ¹³C NMR and high-resolution mass spectroscopy. The nematocidal activities of these compounds were evaluated and the results indicated that these derivatives have better nematocidal activities against Meloidogyne incognita than Aphelenchoides besseyi. Interestingly, cis-isomers of Z-3,6-epidioxy-1-methyl-4-isopropylcyclohexene (2) and Z-3,6-epidioxy-1-methyl-4-isopropenylcyclohexene (4) are more active than their corresponding trans-isomers. Among them, 1,4-epidioxy-4-isopropyl-2-cyclohexenoic acid (8) and 1,4-epidioxy-4-isopropyl-2-cyclohexenecarboxylic acid methyl ester (10) exhibited significant higher nematocidal activities than those of other analogs; therefore the carboxylic acid or carboxyl ester substituent on the ring might be essential for high nematocidal activity. Compared with the toxicity of a commercial nematocide, Oxamyl, these derivatives can be considered effective and promising.

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