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International audience; The 'pollen test' and 'fruit set test' following controlled crossing combinations of parents are the most commonly used methods for pollination incompatibility studies in Olea europaea L. Self-incompatibility (SI), with diagnoses based on the pollen test and pollen germination, indicating self-compatibility, is not always followed by fruit set in this species. To solve this dispute, we have reconciled all observations into a new model. Mismatches between field and laboratory data and between methods are resolved by the dual-successive-screen model (DSSM) supposing two different loci for the expression of the two SI mechanisms. Pollen/stigma is controlled by diallelic SI, or DSI, inferring two G1 and G2 compatibility/incompatibility (C/I) groups for varieties, whereas pollen tubes in ovaries are controlled by poly-allelic SI or PASI with twenty C/I groups. To explain the selfing of varieties, we have suggested that some determinants in the pollen tube and stigma are unstable and degrade (DS-D for degradation of S-determinant) after three to five days, enabling some pollen tubes to avoid being rejected, hence reaching ovules. DSI and PASI in the DSSM and DS-D mechanisms, plus the andromonoecy of the olive tree, complexify SI studies. Inferences from DSSM and DS-D mechanisms in olive orchard practice are detailed.

Contact: berville@supagro.inra.fr; The genetic base of sunflower elite lines is very narrow, due to many years of selection and breeding. To broaden the genetic diversity of the cultivated sunflower, in 1995 73 wild sunflower populations were crossed with 3 cultivated lines (Testers), and 219 hybrid offspring's were evaluated in the field. GCA and SCA effects were computed suggesting for all traits a genetic potential for improvement through selection. Study of the hybrids revealed that the wild accessions bear different genetic abilities to combine with the testers for traits of morphological architecture, phenology and yield (seed weight and seed oil). The variance due to GCA and SCA showed that gene action was additive for days to flowering, branching and plant height. Genotypes derived from the same geographic origin may have either good or poor general combing ability. The correlation between GCA and per se genotype performance was positive for all traits except for seed oil content. This was the first attempt to evaluate wild-cultivated hybrids in sunflower on a large scale and will be the starting point for the management of hybrid Helianthus annuus populations for breeding. GCA and SCA estimations will facilitate the definition of strategies to manage and exploit the natural diversity for this crop

A genetic map was constructed with specific PCRs, DALPs and AFLPs using F8-generation sunflower recombinant inbred lines. RI lines generated from a F2 population of one cross between the two cultivated inbred lines HA89 (maintainer for Pet1 CMS) and LR4 (restorer for Pet1 CMS) were used. A total of 305 markers were located using seven sPCR, 64 DALP and 301 AFLP loci. They were generated with one, seven and 14 primer pairs, respectively. The map construction consisted of a two-step strategy using 6 and 3.1 LOD scores revealed by a simulation file. Mapped markers were assembled into 18 linkage groups covering 2,168.6 cM with an average of 6.1 cM. The distribution of DALPs and AFLPs revealed that both markers tagged different regions to enable covering most of the sunflower genome. This leads to the longest map published so far for sunflower.

Previous papers have dealt with olive chloroplastic DNA (cpDNA) variation revealed using several methods (RFLPs, PCR-RFLPs and microsatellites) and have led to different conclusions. This paper aims to reconsider these divergences. A Southern approach was applied to reveal polymorphism. We used chloroplast DNA of Phillyrea media as a probe. Based on these data, only four chlorotypes were identified in the olive complex. The number of detected lineages was lower than reported in the literature using a direct cpDNA RFLP approach, and was insufficient to distinguish the North African subspecies europaea, maroccana, guanchica and laperrinei. Furthermore, one individual considered belonging to the subspecies laperrinei was questionable. Using other cpDNA and mitochondrial DNA (mtDNA) polymorphisms - based on PCR and RFLP methods, respectively - we showed that this individual displays the cytoplasmic lineage CE1-ME1 characteristic of most Eastern mediterranean cultivars and of Olea europaea subsp. laperrinei from Hoggar. However, based on RAPDs, this individual appeared as mislabelled and probably corresponded to a Mediterranean cultivar or a feral form. In addition, we checked O. e. subsp. laperrinei herbarium samples using two cpDNA microsatellites, which revealed polymorphisms. These also supported that both populations from Niger and Algeria displayed a chlorotype related to CE1. Consequently, based on cpDNA, the relationships of O. e. subsp. laperrinei from Hoggar with a Mediterranean lineage appeared well supported, whereas the South West Moroccan and Macaronesian olives appeared in a different clade using both mtDNA and cpDNA polymorphisms. We conclude that methods based on PCR reveal more polymorphisms in the cpDNA and lead to more-reliable results that the classical RFLP method.

Although the tree development directs the olive tree yield we focus here to describe the main phases, stages and key steps from blossoming to harvest. The olive tree produces much more flowers than all other trees, however, fruit set and final harvest are limited by several parameters. Most articles in literature deal with the physiological aspects of the transformation of the olive flower into the drupe. Little attention has been given to genetic involvements that underlay the physiology and the biochemistry. A comprehensive survey of the literature as much as we can is given with genetic commentaries based upon recent genetic progresses made in the field. The olive tree derived from the oleaster and the oleaster belongs to an intertropical (Asian, African) genus and a major difference between northern species (Fraxinus, Syringa, Ligus‐ trum) is the bare axillary buds at the basis of leaves. This explains why the olive is more susceptible to freeze than other Oleaceae as Fraxinus. Olive flower buds appear on one-yearold twig in terminal position or at the axillary of the leaves.

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; Most olive varieties are not strictly self-incompatible, nevertheless, they request foreign pollen to enhance fruit yield, and consequently orchards should contain pollinisers to ensure fruit set of the main variety. The best way to choose pollinisers is to experiment numerous crosses in a diallel design. Here, the genetic mode of inheritance of SI in the olive is deciphered and it does not correspond to the GSI type, but to the SSI type. It leaves S-allele dominance relationship expression in the male (pollen and pollen tube), but not in the female (stigma and style). Thus, a pair-wise combination of varieties may be inter-compatible in one direction (male to female, or female to male) and inter-incompatible in the other direction. Dominance relationships also explain different levels of self-pollination observed in varieties. Little efficient pollinisers were found and predicted in varieties; nevertheless, some new efficient pair-wise allele combinations are predicted and could be created. This model enables one to forecast compatibility without waiting for several years of yield records and to choose pollinisers in silico.

To begin, the methodology followed to reconstruct the origin and history of the olive is presented. The genetic structure (density of alleles across the geographic distribution of individuals) based on allele frequencies of the present oleaster tree in the Mediterranean Basin computed with different methods of comparison with the genetic structure of cultivars grouped based on their geographic and genetic origins infers several possible scenarios for the transition from the oleaster to the olive. To screen among the scenarios requires solid dating in oleaster presence, diffusion and physical remains (from oleaster and cultivar trees) from different sites. Consequently, reconstructing the origin of the olive is based upon data from diverse disciplines and integrating them appears fruitful. Genetic data show that an event (such as bottleneck, migration, differentiation, adaptation) has occurred, but it cannot be dated. Thus it requires crossing genetic data with data gathered from different biological disciplines to make a strong case for this history. We examine successively

Common sunflower (i.e., Helianthus annuus) is occasionally crossed with other Helianthus species to gain favourable agronomic traits. An interspecific cross between H. annuus and Helianthus mollis was used to examine events that occurred during the five first generations. First generation hybrid plants were verified using GISH, and F1 hybrid (#17) was back-crossed to common sunflower to obtain BC1 (#4) and BC2 (#21). Some BC2 progeny possessed new traits, i.e., compact (Compact plant architecture is due to short inter-node length, short petiole length and short leaf lamina length) architecture without and with corrugated leaves, which were not observed in the parents. These traits were selected for and fixed after the BC2-S3 (#18) to produce a H. mollis introgression line (namely HM374). Although the size of the population was small, we tentatively construct a genetic map using data from the BC2 generation. Two linkage groups were identified carrying H. mollis specific AFLP markers that were associated with compact plant architecture, and one unlinked marker was shown to explain variation for the corrugated leaves. Introgression line HM374 was used to test the inheritance of compact plant architecture in a cross with an elite high oleic line, OL75HO. Microsatellite (SSR) markers were used to genotype F1 and F2 offspring’s. Our data suggested that the line HM374 was still heterozygous for introgression after eight generations. HM374 displays new architecture traits (i.e. compact architecture with or without corrugated leaves) and carries H. mollis fragments anchored on LG1 and LG11 of sunflower public map.

Contact: berville@supagro.inra.fr; International audience; Seventy-seven wild sunflower accessions from USA were compared in France (Mauguio) for 13 quantitative characters using multivariate methods, including clustering, principal component and canonical discriminate analyzes to assess the patterns of morphological and climatic variation. Geographic and climatic data from their sampled sites such as latitude, longitude, elevation, rain fall, temperature, number of rain fall days, temperature range, and sunniness were also analyzed and we sought for correlations of climatic variables and morphological traits. Climatic data clustered the accessions into four groups. Principal component analysis was used to summarize the characteristic habits of annual wild sunflower sampled sites in terms of geography and climates, thus we characterized the ecogeographical profiles of wild sunflowers. As we studied the traits in a common environment we speculated whether local adaptation patterns are sustained by our data. Indeed traits shared by accessions that belong to climatic clusters are suggested to be due to local adaptation

Contact: berville@supagro.inra.fr Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; The present diversity of the olive (crop) and oleaster (wild) tree was investigated with nuclear and cytoplasm markers. Patterns of diversity of the wild form inferred eleven ancestral populations in the East and the West of the Mediterranean basin. Patterns of diversity for cultivars are less clear, but we showed that cultivars admixed to nine groups that corresponded to oleaster ancestral populations. We inferred that nine domestication events took place in the olive, but these origins were blurred by gene flow from oleaster and by human displacements. These origins of domestication probably reflected different reasons and uses to domesticate the oleaster. To cite this article: C Breton et al., C R. Biologies 332 (2009). (C) 2009 Academie des sciences; La diversité actuelle de l’olivier (cultivé) et de l’oléastre (sauvage) a été étudiée avec des marqueurs nucléaires et cytoplasmiques. Les patrons de diversité de la forme sauvage conduisent onze populations ancestrales à l’Est et l’Ouest du bassin méditerranéen. Pour les cultivars, les patrons de diversité sont moins tranchés, mais nous avons montré qu’ils se rattachent à neuf groupes qui correspondent à neuf des onze populations ancestrales d’oléastre. Nous en avons déduit que neuf évènements de domestication différents se sont produits pour conduire à l’olivier actuel, mais les origines sont rendues diffuses du fait de flux de gènes avec l’oléastre et des déplacements des cultivars par l’homme. Ces origines de domestication reflètent probablement diverses motivations et utilisations de l’olivier et de ses produits. Pour citer cet article : C. Breton et al., C. R. Biologies 332 (2009)

International audience; Classical sunflower varieties display a high linoleic acid content in their seeds [low oleic (LO) varieties] whereas genotypes carrying the Pervenets mutation display an increased oleic acid content of above 83% [high oleic (HO) varieties]. Despite the advantage in health terms of oleic acid, the nature of the mutation was still unknown. Previous work reported that HO genotypes carried a specific oleate desaturase (OD) allele. This enzyme catalyses the desaturation of oleic acid into linoleic acid. The present work demonstrates that this allele is organised in two parts: the first section present in both HO and LO genotypes carries a normal OD gene, the second section is specific to HO genotypes and carries OD duplications. The study of mRNA accumulation in LO and HO seeds revealed that the mutation is dominant and induces an OD mRNA down-regulation. Furthermore, OD small interfering RNA, characteristic of gene silencing, accumulated specifically in HO seeds. Considered together, these observations show that the mutation is associated with OD duplications leading to gene silencing of the OD gene and consequently, to oleic acid accumulation. This finding allowed the development of molecular markers characterising the mutation that can be used in breeding programmes to facilitate the selection of HO genotypes.

Contact: berville@supagro.inra.fr Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; The olive belongs to Olea, a complex genus and to a species with six subspecies. Subsp. europaea includes both the cultivated olive and the oleaster, the wild ancestor of the olive. Little is known on the phenotype of fruits from subsp. cuspidata. We aimed to compare europaea and cuspidata trees for oil content and composition and to verify whether natural hybrids may exist between the two subspecies. Specimens were from Kenya and putative natural hybrids between cuspidata and europaea were from Stellenbosch (South Africa). Cultivar and oleaster trees were sampled in France (continental and Corsica), Italy (Continental and Sardinia) and Tunisia. We have examined the fruit (drupe) structure between subsp. cuspidata and europaea and extracted oil from the pulp, seed and total drupe. Comparison for oil content was made between the cultivated olive and the oleaster and some cuspidata trees from Kenya. A few of cuspidata individuals from Botanical gardens do not enable phenotyping for oil content and composition. Oil composition analyses were performed for the main fatty acids to compare the three taxa. We used microsatellite markers at 11 loci to compute genetic distances between cuspidata, oleaster and cultivar trees and to reveal eventual hybrids. The SSR polymorphisms were huge between the two subspecies and they revealed that putative hybrids were true hybrids sampled around olive orchards. The whole comparison of oil content shows that olive cultivars display higher oil content than the subsp. cuspidata and that the oleaster trees are intermediate, whereas for oil composition of the drupe, cuspidata from Kenya shows less oleic acid than europaea. However, the cuspidata trees show seed oil composition similarities with the other two taxa. The discussion deals with possible reasons to explain the differences and of the possible uses of these taxa for breeding both the olive and brown olive

email: berville@supagro.inra.fr Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Olive cultivars are diversified but nothing is known on their origins and if they are local or introduced in any regions. The study aims to determine which traits may help to identify native from introduced cultivars and oleaster trees. We compared cultivars and oleasters from North Tunisia to determine their relationships based on morphological traits, oil composition and SSR genotyping at seven loci. We used those parameters to examine 32 cultivar trees from 17 denominations and 70 oleaster trees sampled. We used multivariate analysis, enabling to retain the best variables, to establish relationships among trees based on morphological and pomological parameters. Gas chromatography was used to determine fatty acid composition of 30 cultivar trees and 13 oleaster trees. We determined for one cultivar Gerboui the steady drupe, pit morphological and oil composition variation ranges in six different contrasted agro-systems. SSR genotyping was performed in polyacrylamide gels after fluorescent labelling. Based on morphology, oleaster trees from agro-ecosystems clustered broadly in an intermediate position between cultivars and oleasters from natural ecosystems. SSR revealed that the feral and genuine oleasters plus cultivars are always overlapping. Relationships between cultivars are displayed in two dendrograms. They revealed six and three main clusters based on Unweighted Pair Group Method (UPGMA) and Ward algorithm, respectively. They mix olive cultivar and oleaster trees suggesting kinship relationships between some cultivar and some oleaster trees. In contrast, on PCA, some morphological parameters split our sample approximately between olive and oleaster trees. Oil composition was similar between cultivar and oleaster trees. Kinship relationships between cultivar and oleaster trees based on molecular polymorphisms suggested that olive cultivars may have origin in local oleasters. Oil composition as fruit descriptors and drupe size appeared inefficient to discriminate between olive and oleaster trees, in comparison to SSR. Our results suggested several domestication events for the olive. It is important to know which cultivars have local origin to promote and sale products from Tunisia as from all around the Mediterranean basin

Correspondance: andre.berville@supagro.inra.fr Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Olive cultivar origins are unknown. We attempted to use multivariate analyses and based Bayesian methods to look for sites of olive cultivar geographic origins. In this study, to establish the method, forty cultivars were chosen with different chlorotypes that represent the olive RAPD-based diversity in the Mediterranean basin. We constructed a dendrogram, as reference, using molecular SSR data. Cultivar origins in the oleaster were examined by using Bayesian clustering methods. It was calculated whether some cultivars may be grouped by admixture analysis to these GRPs and how much olive cultivars admixed to the previously defined oleaster GRPs: two in the east and four in the west of the Mediterranean basin. The comparison between dendrogram and Bayesian analyses showed that when the dendrogram suggests relationships, the Bayesian method quantifies them by probabilities and proportions. The method used is applicable to microsatellite data from other crop/wild complexes

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; The study aims to determine which traits may help to differentiate cultivars and oleaster trees based on drupe and pit morphological traits, oil content and composition and nuclear DNA markers at seven SSR loci. We determined for one cultivar (Gerboui) the steady drupe, pit morphological and oil composition variation ranges in six different contrasted agro-systems. We then investigated 33 cultivars and 40 oleaster trees. PCA analysis on morphological traits was examined. Gas chromatography was used to determine fatty acid composition of 20 cultivars and 13 oleaster trees, and the Soxhlet method was used to determine fruit oil content. SSR genotyping was performed in poly-acrylamide gels. Five clusters based on UPGMA mixed olive cultivars and oleaster trees suggesting kinship relationships between some cultivars and some oleasters; and thus cultivars could derive from domestication of oleaster trees.; L'étude a pour objet de déterminer les caractères permettant de différencier les oléastres et les cultivars d'olivier en se basant sur la morphologie du fruit et du noyau, le contenu et la composition de l'huile, et de la variation génétique à 7 locus SSR. Nous avons au préalable déterminé l'amplitude de la variation morphologique et biochimique induite par l'environnement pour le cultivar Gerboui dans 6 agro-écosystèmes différents. Nous avons ensuite caractérisé 33 cultivars et 40 d'oléastres. La variation morphologique est analysée par ACP, la composition en acides gras par chromatographie en phase gazeuse. Nous avons utilisé la méthode de Soxhlet pour quantifier la teneur en huile de 20 cultivars et 13 oléastres. Les SSR ont été séparés en gel de poly-acrylamide. Cinq groupes d'individus construits selon la méthode UPGMA basés sur les données génétiques suggèrent des parentés étroites entre oléastres et cultivars qui découleraient de domestication locale ou de flux de gènes entre les deux compartiments.

The isolation of mitochondria from sugar beet and sunflower has been carried outina buffered medium of high ionic strength (I=1.40 M). Them tDNAs obtained were enriched for supercoiled molecules of low molecular weight. Chloroplast and mitochondrial DNA were successively prepared and used from a single leaf preparation for further analysis of restriction fragment length polymorphism. The few available wild relatives of sugar beet or sunflower have also been analyzed by comparison of the restriction patterns of their chloroplast and mitochondrial DNAs.

Correspondance: berville@supagro.inra.fr Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Aim The oleaster is believed to have originated in the eastern Mediterranean, implying that those in the western Mediterranean basin could be feral. Several studies with different molecular markers (isozymes, random amplified polymorphic DNA, amplified fragment length polymorphism) have shown a cline between the eastern and the western populations, which supports this hypothesis. To reconstruct the post-glacial colonization history and establish a relationship between olive and oleaster populations in the Mediterranean basin, analyses were carried out on the genetic variation of chloroplast DNA (chlorotype) and at 12 unlinked simple sequence repeat (SSR) loci, sampling a total of 20 oleaster groves. Location: This is the first known large-scale molecular study of SSR loci based on samples of both oleasters and cultivars from the entire Mediterranean basin.Methods Samples were taken from 166 oleasters in 20 groves of modern populations, and 40 cultivars to represent molecular diversity in the cultivated olive. The Bayesian method and admixture analysis were used to construct the ancestral populations (RPOP; reconstructed panmictic oleaster populations) andto estimate the proportion of each RPOP in each tree. If one tree can be assigned to two or more RPOPs, it can be regarded as a product of hybridization between trees from different populations (i.e. admix origin).Results: On this first examination of the SSR genetic diversity in the olive and oleaster, it was found to be structured in seven RPOPs in both eastern and western populations. Based on different population genetic methods, it was shown that: (1) oleasters are equally present in the eastern and the western Mediterranean, (2) are native, and (3) are not derived from cultivars. Chlorotypes (one and three in the eastern and western Mediterranean, respectively) revealed fruit displacement for the oleasters.Main conclusions: Oleaster genetic diversity is divided into seven regions that could overlay glacial refuges. The gradient, or cline, of genetic diversity revealed by chloroplast and SSR molecular markers was explained by oleaster recolonization of the Mediterranean basin from refuges after the last glacial event, located in both eastern and western regions. It is likely that gene flow has occurred in oleasters mediated by cultivars spread by human migration or through trade. Animals may have helped spread oleasters locally, but humans have probably transported olives but not oleaster fruits over long distances. We found that cultivars may have originated in several RPOPs, and thus, some may have a more complex origin than expected initially.

With more than 100 accessions, the CBNMP olive collection includes a major part of the French germplasm. We used molecular markers to characterise all accessions and to study genetic relationships between cultivars. Firstly, 497 olive trees were genotyped using 32 RAPD markers. We identified 114 RAPD profiles and detected several cases of mislabelling, synonymy and homonymy. Secondly, for each RAPD profile, one tree was analysed using mtDNA RFLPs to determine the cytoplasmic lineage of each cultivar and using five nuclear SSR loci. French germplasm displayed ME1, MOM and MCK mitotypes with ME1 prevailing (84%). Based on SSR markers, we revealed a slight differentiation between French cultivars growing in the West and the East side of the Rhône Valley. This study allowed us to construct a molecular data-base for the reference collection and to analyse genetic diversity for further prospecting, and for introducing new olive accessions.

To obtain introgressed sunflower lines with improved disease resistance, interspecific crosses were performed with foreign perennial species. We report on several unusual features displayed by these hybrid plants. The methods used to produce the kernels affected yield and genotypes of progeny. Phenotypic traits and DNA markers were investigated in 97 plants derived from cross-pollination between annual diploid cultivated sunflower (Helianthus annuus) and the perennial diploid species H. mollis or H. orgyalis, and the reverse reciprocal crosses. The level of hybridization in progeny was determined using RAPD and RFLP markers. Hybridization was performed by leaving embryos to develop normally on the head (classical crossing) or using embryo rescue. All observed plants derived from H. mollis were diploid (2n = 34). Phenotypes were predominantly similar to the female when cultivated sunflower was the female parent. Progeny from crosses using a wild species as the female parent resembled that parent. Thus, reciprocal crosses led to different progeny. F1 sister progeny shared different sets of molecular markers representing a few of those of the wild species used as the pollen donor. Our results indicate mechanisms leading to the unusual event of partial hybridization. Possible mechanisms behind these unusual events and their possible impact on evolution are discussed.

Pervenets is a sunflower mutant having a seed oil oleic acid content greater than 65%. All lines derived from the mutant Pervenets population display seed oil with a high oleic acid content [HOAC], over 80%. Linoleic (LO) and [HOAC] genotypes carry specific RFLP markers, oleLOR and oleHOS, revealed by oleate-desaturase cDNA used as a probe. Linkage disequilibria between the OleHOS allele and Pervenets mutation, and oleLOR and [LO] were without any exception. We studied the inheritance of [HOAC] in F2 progenies from a cross [LO] x [HOAC]. This study has shown one dominant allele for [HOAC] that cosegregated with the oleate-desaturase oleHOS, [HOAC]-specific RFLP. Variance analyses revealed almost complete dominance and that oleHOS marker explained 86% of the OAC variation. F6 recombinant inbred lines segregating for [HOAC] / [LO] showed that all [HOAC] RI lines carried oleHOS, but half of the RI lines carrying oleHOS were [LO]. Conversely, the absence of [HOAC] RI lines carrying oleLOR is evidence against recombination having taken place between the oleHOS locus and the Pervenets mutation locus. The [HOAC] trait is therefore due to 2 independent loci: the locus carrying the oleHOS allele and another locus. One allele, supole, at this second locus may suppress the effect of the oleHOS allele on the [HOAC] trait. Preliminary results with SSR (170 microsatellites, 500 cM) indicated that the oleHL and the supole loci are independent and explained 47.14 and 32.2% of the OAC variation respectively. The existence of the Pervenets mutation, supole and epistatic combinations for modifier alleles leading to [HOAC] trait has never been suggested. It may explain the discordant results found in our segregating populations and literature.

The possibility of gene flow between cultivated and wild species of different crops was assessed, focussing on sunflower and its wild relatives or cultivated forms (annual Helianthus annuus, H. argophyllus, H. bolanderi, H. petiolaris, and perennial rigidus, H. tuberosus). Data were compiled from the literature and an attempt was made at determining the efficiency of possible crosses between annual and perennial species. The risk of a cultivated allele escaping from sunflower to uncontrolled forms (volunteers, H. annuus and H. tuberosus feral forms) was addressed, the fate of such alleles in the wild also being examined. An attempt was made to define some of the pressures likely to limit the spread of wild forms in nature, or that could prevent or impede the spread and increase the frequency of alleles from cultivated plants. Risks of spread of transgenes from sunflower varieties in Europe where feral forms are present but no natural Helianthus species were assessed. The emergence of transgenic or biologically engineered varieties of sunflower demands that attention be focussed on this field.

SUMMARY A diallel crossing design was carried out during 1999 and 2000 seasons near Montpellier under field nursery conditions. Intercrosses of seven sunflower lines were performed between genetic (ms2) or cytoplasmic male sterile (PET1) and standard versions using bagged heads. These lines contrasted for oleic acid content in oil. Four lines with high oleic acid content originated from Pervenets. Three linoleic inbred lines were added to the crossing design. Male fertile lines were selfed in the same conditions. F1 seeds and those from selfed inbred lines were analyzed for fatty acid composition using gas chromatography. Year effect, reciprocal or maternal effects, general combining ability and specific combining ability effects were found to be significant. The level of dominance of high oleic acid content appeared related to the genetic background. We found previously that 83HR4, a linoleic line of the diallel, was bearing a suppressor allele canceling Pervenets mutation effect. In reciprocal crosses with high oleic lines, this line had a strong maternal negative effect on oleic acid content.

Eighty-four plants obtained from the pollination of the annual diploid cultivated sunflower, Helianthus annuus, by the perennial diploid species H. mollis were obtained naturally from mature seeds (62 plants) or following embryo rescue procedures (22 plants) and subsequently studied for phenotype traits and DNA markers. Twenty-two plants were obtained from the reverse cross as a result of natural seed development. The level of hybridization was determined using random amplified polymorphic DNA and restriction fragment length polymorphism markers. All of the resulting plants were found to be diploid 2n=34. Reciprocal crosses led to different progenies, with phenotypes that were predominantly similar to that of the female sunflower or the H. mollis type. The embryo rescue procedure enhanced the level of hybridization, whereas natural seed development led to fewer hybrids. Molecular markers unique to the female or the male parent indicated mechanisms leading to partial hybridization.

The study of genetic diversity within the olive-tree (cultivated and wild forms) may be useful to reveal agronomic traits in the wild germplasm and to try to understand the history of the olive-tree domestication. In this way, a study of nuclear and mitochondrial DNAs of cultivated and wild olives from two Corsican and Sardinian Mediterranean islands was performed using RAPD and RFLP markers. Our results show that most of the varieties and most of the oleasters were separated using the UPGMA dendrogram based on the Nei and Li similarity index. Most of oleasters carried either the MOM or MCK mitotype, characteristic of olives in the Western Mediterranean, whereas most of the varieties carried the ME1 mitotype, characteristic of olives in the East Mediterranean. The results indicate that the combination of mitotype and RAPD markers can be used as a powerful tool for differentiating two groups in the wild forms: the Western true oleasters and the feral forms. The true oleasters are characterized by a Western mitotype and a Western RAPD pattern. Feral forms originate either from varieties or from hybridisation between a variety and an oleaster. Consequently, as expected, some of them aggregated with the varieties from which they were derived. The other feral forms are clustered with the oleasters and were detected only by their mitotype determination. This study has also permitted us to differentiate two populations of cultivated olives in Corsica: one with close relationships with Italian varieties (influenced by the East) and one selected from local oleasters probably due to a better local adaptation than foreign varieties.

Four hundred and four individuals belonging to the species #Olea europaea# were characterised using mitochondrial DNA (mtDNA) RFLPs. Twelve mitotypes were distinguished. The combination of mtDNA information with cpDNA polymorphism (characterised in a previous study) led us to recognise 20 cytoplasmic lineages of which seven were found in the Mediterranean area (oleasters, cultivars and #O. e.# subsp. #maroccana#). In the olive complex, strong cytoplasm genetic differentiation was revealed (Fst = 0.73). Very strong linkage disequilibrium between cpDNA and mtDNA polymorphisms was observed, particularly in the Mediterranean subspecies #europaea#. This high congruence between genetic structure based on cpDNA or mtDNA sustains a low level of recurrent mutation in both organelle DNAs and, thus, the polymorphisms used in this study were pertinent to reconstruct olive phylogeography. In the Mediterranean area, genetic drift due to population regression during Quaternary glaciations, and founder effects associated with the postglacial seed dissemination, have probably contributed to the existence of a high genetic linkage disequilibrium between cpDNA and mtDNA polymorphisms. Thus, four Mediterranean cytoplasmic lineages, clearly distinguished both by cpDNA and mtDNA polymorphisms, most likely reflect four distinct relic populations during Quaternary glaciations. Finally, #O. e.# subsp. #maroccana# from South Morocco, which also displayed specific cytoplasmic lineages, should be considered as another relic Mediterranean population. (Resume d'auteur)

Les profils RAPD de 121 cultivars d'olivier ont été comparés à ceux de 20 populations naturelles d'oléastres de l'est et de l'ouest de la Méditerranée. En considérant les proximités des profils RAPD entre les cultivars de l'est et de l'ouest et les populations, des différences nettes apparaissent entre les groupes de cultivars. Les cultivars d'Israël, Turquie, Syrie, Grèce et Sicile sont, avec peu d'exceptions, proches des oléastres de l'est; à l'opposé les clones d'Italie continentale, de France continentale, de Corse, d'Espagne et du Maghreb sont proches des oléastres de l'ouest. Cette structure génétique est cohérente avec une sélection locale des cultivars tout autour du bassin Méditerranéen. Les cultivars ont aussi été caractérisés par le cytotype mitochondrial. Cette information montre que la grande majorité (103 sur 121) des cultivars porte les mitotypes ME1 ou ME2, et aurait donc une origine maternelle dans les populations de l'est. Cependant, le processus de sélection qui implique l'hybridation par le pollen des populations locales, pourrait mener à avoir un profil RAPD plus proche des populations de l'ouest que des populations naturelles de l'est. En outre, les autres cultivars avec les mitotypes de l'ouest MOM ou MCK, ont généralement conservé un profil RAPD proche des populations naturelles de l'ouest. En conséquence, elles pourraient résulter de formes exclusivement locales (comme en Corse). Cependant, les cultivars qui portent de tels mitotypes pourraient aussi avoir été sélectionnés à partir d'hybrides ou de génotypes introgressés entre les oléastres de l'ouest et les variétés, introduites de l'est, utilisées comme parent mâle, conduisant à un profil RAPD de l'est. Le processus de domestication de l'olivier apparaît dissymétrique: la Méditerranée de l'ouest serait une zone où les oliviers de l'est, une fois introduits, auraient été hybridés et rétro-croisés avec les oliviers indigènes.

One hundred and thirteen olive (Olea europaea L.) accessions were characterized using randomly amplified polymorphic DNA (RAPD) markers. Forty-five polymorphic RAPD markers were obtained enabling us to distinguish 102 different RAPD profiles. The approximate estimation of the probability of obtaining the same RAPD profile for two different trees was between 6.75 × 10 -5 and 4.82 × 10 -14 . A dendrogram was constructed using Ward's minimum variance algorithm based on chi-square distances. This led to a more clear-cut classification of profiles than the classical approach of unweighted pair group method with arithmetic average. Twenty-four clusters of RAPD profiles were shown in Ward's dendrogram. Reliability of the dendrogram structure was checked using variance analysis. RAPD data exhibited an acceptable resolving power for cultivar identification. A combination of three primers was proposed for rapid molecular identification of cultivars in collections and in nurseries. Olive (Olea europaea) is of great socioeconomic importance in the Mediterranean basin. Its cultivation is expanding because of increased demand for olive oil. A great number of olive cultivars (presumed clones) are grown throughout the world. Several hundred supposedly clonal accessions are described in the main countries of the Mediterranean basin. In France about 150 cultivars are registered (Andlauer, 1997). During the history of olive cultivation, as for other tree species, different cultivars may have been given the same name, whereas a cultivar may have been named differently in different countries. Therefore, cultivar and denomination (usual or local name) are ambiguous terms. Vegetative propagation of trees of agronomic interest has produced numerous clones (Zohary and Hopf, 1994). Conse- quently, genetic uniformity within a given cultivar, and thus, within a denomination, is expected. Cultivar identification based on phenological and morphological phenotypes from field or nursery observations may not be adequate to assign cultivar identity due to environmental effects on traits. Moreover, the

Crosses were made between three cytoplasmic male-sterile and five restorer sunflower inbred lines. F1 hybrids, including their parents, were studied for their embryogenetic ability. Sterilized seeds were germinated in culture tubes on agar-solidified basal medium. Seven days after germination, epidermal layers from hypocotyls were transferred into MS and B5 liquid-midia for 5 and 8 days respectively. Then they were transferred to MS-120 solid-medium with a high level of sucrose (120 g/l). The experimental design was complete randomized blocks with three replications. Each replication per genotype consisted of three Erlenmeyer flasks with 20–25 epidermal layers (explants). Analysis of variance indicated the presence of significant variation among genotypes for all traits studied. General combining ability (GCA) and specific combining ability (SCA) showed significant effects for the studied traits. The highest value of GCA for the number of embryogenic explants per 100 explants plated (EE/100EP) belongs to parental female line ’CMS-PET1 B9’. This inberd line also gave a high positive GCA effect for the number of embryos per ten embryogenic explants (E/10EE). Additionally, it had the highest values for EE/100EP and E/10EE (41.70 and 19.28 respectively) and should be a promising parent in crossing programmes for the enhancement of somatic embryogenesis in the sunflower. The highest values of specific combining ability (SCA) for EE/100EP and E/10EE belong to the F1 hybrid ’CMS-PET1B9 ’x’ RT1B11’ which has produced 53.45 embryogenic explants/100 explants and 9.67 embryos per ten embryogenic explants.

Two highly repeated EcoRI (0.45 × 10(6)) and BamHI (0.17 × 10(6)) fragments per haploid genome were found in sugar beet genomic DNA. Both fragments were located by 6% acrylamide-gel electrophoresis, purified and cloned in pUC18. Four of the inserts corresponding to each family were chosen for further study. Both fragment families display the main characteristics of the satellite DNA of animals and plants. The EcoRI and BamHI fragment families are arranged in long tandem arrays. Fragments of the EcoRI family (pBVE) were analyzed. They vary both in sequence and in length (158-160 nt) in comparison with the consensus sequence of 159nt. Both families are A-T rich; pBVE is 59% rich while pBVB is 69% rich. The BVESAT family is present in all the members of the section Vulgares. It is conserved in the section Procumbentes with 80% homology and the same length, but is not detectable in the Corollinae. The sequence variation rate and the variation in length (330±5 nt) are of the same order in comparison with those of the BVESAT family. However, the BVBSAT family is present in species of the section Vulgares only. As regards other plant satellite DNAs, the BVESAT family shares homology with Allium cepa satellite DNA, with three of the yeast centromeric sequences, and with three Arabidopsis thaliana sequences. The BVBSAT family is unique to the Vulgares and does not share any homology with other plant or animal satellite DNAs sequences so far.

Mitochondrial and chloroplastic proteins of the three sections Vulgares, Corollinae and Procumbentes of the genus Beta were analysed by polyacrylamide gel electrophoresis in the presence of SDS. Most of the chloroplastic or mitochondrial polypeptides are common to the three sections, but some are present in one section only. Thus their presence in an individual allows it to be assigned to a section. The variation of chloroplastic and mitochondrial poly-peptide profiles of closely related species has not been frequently reported. Thus the question arises about the differentiation of these species and subspecies. We found that table beets display polypeptides present either in the Vulgares or in the Corollinae, and consequently they probably result from an old hybridization.

The soluble mitochondrial adenosine triphosphatase was purified from sugar beet (Beta vulgaris L.) root tissue. The enzyme consisted of six subunits with different molecular weights (α = 56 300; β = 54 000; γ = 35 000; δ = 25 500; δ′ 23 000; ϵ = 15 000). Adenosine triphosphatase associated with the submitochondrial particles displayed the same properties of other plant F1-ATPase. The identification of the largest subunits (α, β, γ) was made using beef heart antisera while the δ, δ′ and ϵ, were detected by SDS-PAGE. Some contaminant polypeptides were also detected in the SMP. We verified that among the total mitochondrial protein fraction these antisera can recognize the polypeptides corresponding to the F1 subunits. The comparison of immunoblots obtained with plants from species belonging to the Vulgares, Corollinae and Patellares has been carried out. The F1-ATPase subunits did not vary in size, they were compared to other plant F1-ATPase. Three polypeptides of MW 14 300 for Patellares, 15 000 for Vulgares and 16 300 for Corollinae allow to differentiate the sections of the Beta genus. The relationship between sections and cultivated forms was discussed. With regards to the comparison of the maintainer O-type and cytoplasmic male-sterile line we did not find any difference between the ATPase activities of submitochondrial particles and purified fractions. The polypeptide sets recognized with anti-F1-ATPase serum looked the same.

To produce hybrids, one member of the parental line is genetically made male-sterile. This male-sterile trait is encoded by mitochondria so that it is maternally inherited. Consequently, the progeny of a male-sterile plant is fully sterile. Nevertheless, during the handling of cytoplasmic male-sterile seed stocks, some mixture with seeds of the maintainer lines can occur. Up to the present time, the only way to check the homogeneity of the cytoplasmic male-sterile seed stock was to grow the plants until flowering time. We have developed a method which can be used immediately after the harvest, allowing us to check samples from both sunflower and sugar beet. We used the mitochondrial plasmid, present only in the maintainer lines, as a probe for the total nucleic acids prepared from the cytoplasmic male-sterile seed stocks which might be contaminated. The signals compared to those of samples artificially contaminated allow us to measure as few as one male-fertile seed in 1000 seeds in a rapid and accurate manner.

T-toxin and the insecticide methomyl dissipate the membrane potential in mitochondria isolated from a Texas (T) cytoplasmic male-sterile corn. These compounds have no effect on mitochondria isolated from normal (N) corn. We show here that treatment of Texas mitochondria with oligomycin drastically enhances the sensitivity of these mitochondria to T-toxin and to methomyl. In addition, T-toxin and methomyl are able to specifically inhibit ATPase activity of soluble F1-ATPase purified from Texas mitochondria. These observations would indicate that the 13-kDa protein, recently implicated as the target of t-toxin and methomyl (Dewey et al., Proc. Natl. Acad. Sci. U.S.A., 84 (1987) 5374–5378), is associated with the mitochondrial ATPase.

A circular plasmid called plT is found in mitochondria of sunflower ( Helianthus annuus ). Its nucleotide sequence has been determined and analyzed in order to understand its possible role and origin. The nucleotide sequence exhibits a 159 base pair region with highly organized repeats. The sequence of plT shows no major homology with other plasmids of higher plants although organized patterns are present in the circular plasmids. We also report the existence of two related mitochondrial plasmids in a line of H. annuus and in the H. petiolaris fallax species. In addition, plT plasmid has been detected in total cellular DNA of male-sterile sunflower with a copy number of a hundred times lower than in the male-fertile one.

The first linkage map of the olive (Olea europaea L.) genome has been constructed using random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphisms (AFLP) as dominant markers and a few restriction fragment length polymorphisms (RFLP) and simple-sequence repeats (SSR) as codominant markers. Ninety-five individuals of a cross progeny derived from two highly heterozygous olive cultivars, Leccino and Dolce Agogia, were used by applying the pseudo test-cross strategy. From 61 RAPD primers 279 markers were obtained - 158 were scored for Leccino and 121 for Dolce Agogia. Twenty-one AFLP primer combinations gave 304 useful markers - 160 heterozygous in Leccino and 144 heterozygous in Dolce Agogia. In the Leccino map 249 markers (110 RAPD, 127 AFLP, 8 RFLP and 3 SSR) were linked. This resulted in 22 major linkage groups and 17 minor groups with fewer than four markers. In the Dolce Agogia map, 236 markers (93 RAPD, 133 AFLP, 6 RFLP and 4 SSR) were linked; 27 major linkage groups and three minor groups were obtained. Codominant RFLPs and SSRs, as well as few RAPDs in heteroduplex configuration, were used to establish homologies between linkage groups of both parents. The total distance covered was 2,765 cM and 2,445 cM in the Leccino and Dolce Agogia maps, respectively. The mean map distance between adjacent markers was 13.2 cM in Leccino and 11.9 cM in Dolce Agogia, respectively. Both AFLP and RAPD markers were homogeneously distributed in all of the linkage groups reported. The stearoyl-ACP desaturase gene was mapped on linkage group 4 of cv. Leccino.