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The potential of isozymes for distinguishing asparagus varieties was carried out by a survey on 21 varieties using 10 enzyme systems : GOT, SkDH, DIA, PGM, MDH, IDH, PGD, ACP, PGI, MR and ADH . Only 3 enzymes, SkDH, GOT and PGM, showed useful polymorphisms . The varieties were found heterogeneous according to their genetic structure : open pollinated varieties were more heterogeneous than clonal hybrids ; the Fl hybrid and the vitroclones were homogeneous . As expected from the narrow genetic basis of the varieties, only a few alleles per isozyme locus were present. Moreover, for each enzyme, one allele or type was predominant so that the discriminating power of the method was low . However some of the varieties could be identified and different applications of the results are presented .Abbreviations: D .U .S . -Distinction-Uniformity-Stability, ACO -aconitase, ACP -acid phosphatase, ADHalcohol dehydrogenase, CAT -catalase, DIA -diaphorase, END -endopeptidase, GOT -glutamate oxaloacetate transaminase, IDH -isocitrate dehydrogenase, MDH -malate dehydrogenase, MR -menadione reductase, PGIphosphoglucoisomerase, PGM -phosphoglucomutase, PGD -phosphoglucose dehydrogenase, POX -peroxidase, SkDH -shikimate dehydrogenase .

— Les diagrammes protéiques de 280 variétés d'orge ont été décrits. La technique d'électrophorèse sur gel d'acrylamide contenant du SDS permet de séparer les variétés en 86 groupes. En utilisant en plus les diagrammes des estérases et des phosphatases acides, il est possible d'établir une clé d'identification pour les 12 orges d'hiver et 13 orges de printemps les plus cultivées en France. orge / enzyme / protéine / électrophorèse / identification variétale Summary — Identification of barley varieties using electrophoresis. Description of 280 varieties. Two hundred and eighty varieties of barley are described for their seed protein patterns using SDS-PAGE. This technique enables us to make 86 groups. By the additional use of esterases and acid phosphatases, it is possible to make an identification key for the 12 winter varieties and 13 spring varieties most used in France. barley / enzyme / protein / electrophoresis / varietal identification

Electrophoretic markers were used to describe varieties of carrot and tested for their use in distinguishing and identifying them. Seed proteins and ten enzyme systems (PGI, PGM, PGD, ACP, ADH, GOT, IDH, MDH, MR and SkDH) were studied in a set of varieties and selection hnes. Using the proteins from bulk samples of more than 25 seeds per variety, consistent results were obtained which enabled the 38 varieties studied to be divided into 14 groups. Among the enzymes studied, PGI, PGM and PGD were found to be convenient for distinction purposes. They demonstrated the heterogeneity of the varieties and their combined use enabled most of them to be distinguished from one another. The use of electrophoretic markers for distinguishing varieties is discussed.In carrots, agronomic value is rather subjective and information on traits such as earliness or resistance to diseases is as useful to the grower as knowledge ofthe production capacity. Accordingly, there is no test of agronomic value, and distinctness tests which are based on the comparison of morphological traits become all the more important for the registration of new varieties. Due to the increasing number of carrot varieties (80 in the Erench list for 1992 and about 250 in the European list) it will become more and more diflicult to establish a clear distinction between any two varieties. It will become all the harder as selection has resulted in reduced variabihty: almost all new varieties are of the 'Nantaise' type, that is they are cylindroconical, smooth, well-coloured and have mediumlength foliage. Eurthermore, homogeneity is rather difficult to assess because most of the available morphological markers involve the root whose phenotypic expression is very susceptible to small-scale variations in the soil. Therefore, biochemical markers have been investigated for their use in distinctness studies.A set of 45 varieties and selection lines was studied. The varieties were purchased by the GEVES experimental station of Brion. The experimental lines and hybrids were kindly provided by A. Bonnet. The varieties 'Major' and '9106' were tested with different seedlots (different places and years of production) to assess stability. At least 30 plants per variety were evaluated, except for L4 in which the germination rate was very low and only 23 plants were available.For the enzymes, 20 mg of leaves from 3-week-old seedlings were crushed in 150 fil of extracting buffer (Tris HCl O.IM, pH 7.5 containing 1 % PVP 40, 1 % mercapto-ethanol). The extracts were then loaded on paper wicks which were then inserted in horizontal starch gels (12% starch in histidine citrate buffer). The staining solutions were the same as those described by Westphal andWricke (1989, 1991). For the seed proteins, a bulk of 25-50 seeds were ground together in 150-200 fil extracting buffer (Tris-HCl 0.06M, pH 6.8 containing 2% SDS, 8% mercapto-ethanol and 15% DMF). Next, 9 /il ofthe extracts were loaded on a discontinuous polyacrylamide gel (concentration gel: 3,5% polyacrylamide, Tris-glycine pH 6...

Mating disruption by sex pheromones is a sustainable, effective and widely used pest management scheme. A drawback of this technique is its challenging assessment of effectiveness in the field (e.g., spatial scale, pest density). The aim of this work was to facilitate the evaluation of field-deployed pheromone dispensers. We tested the suitability of small insect field cages for a pre-evaluation of the impact of sex pheromones on mating using the grape moths Eupoecilia ambiguella and Lobesia botrana, two major pests in vineyards. Cages consisted of a cubic metal frame of 35 cm sides, which was covered with a mosquito net of 1500 μm mesh size. Cages were installed in the centre of pheromone-treated and untreated vineyards. In several trials, 1 to 20 couples of grape moths per cage were released for one to three nights. The proportion of mated females was between 15 to 70% lower in pheromone-treated compared to untreated vineyards. Overall, the exposure of eight couples for one night was adequate for comparing different control schemes. Small cages may therefore provide a fast and cheap method to compare the effectiveness of pheromone dispensers under standardised semi-field conditions and may help predict the value of setting-up large-scale field trials.