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The kola tree (Cola nitida) belongs to family Malvaceae grown mainly for its seed. It is highly prized for its socio-cultural and industrial uses. However, there is a significant high variability due to a high proportion of allogamy in the reproduction mode. The influence of substrate and genotype on kola tree cuttings has been studied in order to propagate it vegetatively. Six growing substrates: 100% Black soil, 50% Black soil + 50% Wood sawdust, 100% Wood sawdust, 50% Soil + 50% Black-Coco, 100% Black-Coco, 50% Wood sawdust + 50% Black-Coco were tested on genotypes 305 and D9L7A1 using a split-plot experimental design with genotype as main factor and substrate as subplot treatment replicated three times. The experimental unit constituted 20 cuttings. Six months after transplanting, the average success rate of tunnel cutting from the kola tree to the nursery was 76.2±7.6%. The best success rates were obtained with 100% Wood sawdust, 100% Black soil and 50% Black coco + 50% Wood sawdust substrates with 85±4.5, 80.8±6.6 and 79.7±5.8%, respectively, regardless of the plant material used. The substrates 100% Black soil and 100% Wood sawdust gave the best results on growth parameters such as aerial dry biomass, height growth, roots number and new formed leaves. It also showed that genotype D9L7A1 had a higher vegetative leaves and roots development than genotype 305. These genotypes were well suited for cutting. Key words: Cola nitida, cuttings, genotype, substrate.

Alfalfa (Medicago sativa), known as green gold, is one of the best-known forage plants in the world. Alfalfa is an autotetraploid allogamous plant with a large genetic diversity among its cultivars. This diversity is due to self-incompatibility, a high rate of allogamy, and open pollination. This study aimed to investigate the biodiversity of grain storage proteins of M. sativa using gel electrophoresis. For this purpose, seed proteins of 12 Iranian genotypes including seeds collected from Lenjan of Isfahan, Dashte Qazvin, Asadabad, Qasr Shirin, Taleghan Qazvin, Malayer, Isfahan, Saqez, Gonbad Kavous, Kamyaran, Shiraz, and Najafabad of Isfahan were studied and a total of 22 strips were identified. Then, the strips were used to estimate the genetic distance of alfalfa genotypes. The results of the study based on the presence and absence of specific protein bands in the seed protein pattern showed that genotypes 1 (Collection from Isfahan-Lenjan) and 12 (Collection from Najafabad-Isfahan) have the most variation. A similarity matrix was calculated and cluster analysis was performed based on the Jaccard similarity coefficient by the UPGMA method. The similarity coefficients ranged from 0.3 to 1. In general, classification based on cluster analysis showed a similar trend to the differences observed in gel electrophoresis. The total protein of population number 12 (Najafabad population of Isfahan) had the highest amount among the studied genotypes. The highest and lowest number of bands were related to genotype number 12 (population of Najafabad, Isfahan) and genotype number 11 (population collected from Shiraz), respectively. Therefore, the results showed that the protein pattern of alfalfa seeds based on the presence and absence of protein bands can determine genetic diversity. These findings can be used in future research in the field of proteomics and breeding studies in future.

Mating system influences local population genetic structure, effective size, offspring fitness and functional variation. Determining the respective importance of self- and cross-fertilization in hermaphroditic flowering plants is thus important to understand their ecology and evolution. The worldwide invasive species, Ludwigia grandiflora subsp. hexapetala (Lgh) presents two floral morphs: one self-compatible short-styled morph (S-morph) and one self-incompatible long-styled morph (L-morph). Most invasive populations worldwide are only composed of self-incompatible L-morphs, which questions the importance of sexual reproduction during the invasion. In this study, we identified the mating systems of western European experimental and natural populations of Lgh by comparing structural characteristics of pollen and style, by studying self- and cross-pollen tube elongations and the viability of the resulting seeds and seedlings in both morphs. Our results showed no differences in pollen shape and stigma surfaces among and between the two floral morphs. In the self-incompatible L-morph flowers, self-pollen tubes were stopped tardily, in the ovarian area, and were unable to fertilize the ovules. This first formal identification of a late-acting, prezygotic self-incompatible system in Ludwigia genus questions on the distribution of this mating system in the Myrtales order. In the self-compatible S-morph flowers, rarer in worldwide invasive populations, self-pollen always succeeded to self-fertilize the ovules that nearly all developed into viable seedlings. However, cross-pollen tubes always elongated faster than self-pollen tubes. S-morph individuals may thus advantage preferential allogamy over selfing when cross-pollen is available despite its self-compatibility. As expected in late-acting self-incompatible systems, L-morph flowers authorised 0.2{per thousand} of selfed seeds during the uppermost flowering season, that increased to 1{per thousand} at the end of the flowering season. Such delayed selfing resulting in a significant quantity of viable floating seeds may contribute to the local regeneration, seed bank and propagation of the L-morph, which may explain its invasion success worldwide. Management plans of Lgh would gain to consider the mixed mating system we identified.

Aim. The necessity to generalize information from the literature as to the features of Malus spp. reproductive biology caused by the prospects of using apple trees as a valuable plant and associated with the development of the effective methods of reproduction in terms of the biodiversity conservation problem, enriching the range of ornamental woody plants, introduction and selection. Methods. In the process of analysis and synthesis of available scientific information on the reproductive biology of the genus Malus, the interconnected and interdependent processes of reproduction in general and the development of individual reproductive organs with phylogenetic, biotic, abiotic and anthropogenic factors are generalized. Results. The main characteristics of the generative sphere and the factors, influencing the manifestation of the reproductive function of Malus spp. both in natural areas and the conditions of introduction had been revealed. An attempt is made to find and explain the differences in the realization of reproductive potential within the genus. The need to take into account ecology and evolution in the study of reproductive processes Malus spp. at the level of individual organisms, populations and species are emphasized. Conclusions. Critical aspects of the reproductive biology of the genus Malus are allogamy and gametophytic self-incompatibility, with some differences in the realization of reproductive potential due to polyploidy, facultative apomixis, self-incompatibility and hybridization, which will contribute to the development of effective methods of ornamental species and varieties of apple trees reproduction.

Transcriptomic analysis of tomato genotypes contrasting for stigma position suggests that stigma insertion occurred by the disruption of a process that finds a parallel in Arabidopsis gynoecium development. Domestication of cultivated tomato (Solanum lycopersicum L.) included the transition from allogamy to autogamy that occurred through the loss of self-incompatibilty and the retraction of the stigma within the antheridial cone. Although the inserted stigma is an established phenotype in modern tomatoes, an exserted stigma is still present in several landraces or vintage varieties. Moreover, exsertion of the stigma is a frequent response to high temperature stress and, being a cause of reduced fertility, a trait of increasing importance. Few QTLs for stigma position have been described and only one of the underlying genes identified. To gain insights on genes involved in stigma position in tomato, a bulk RNA sequencing (RNA-Seq) approach was adopted, using two groups of contrasting genotypes. Phenotypic analysis confirmed the extent and the stability of stigma position in the selected genotypes, whereas they were highly heterogeneous for other reproductive and productive traits. The RNA-Seq analysis yielded 801 differentially expressed genes (DEGs), 566 up-regulated and 235 down-regulated in the genotypes with exserted stigma. Validation by quantitative PCR indicated a high reliability of the RNA-Seq data. Up-regulated DEGs were enriched for genes involved in the cell wall metabolism, lipid transport, auxin response and flavonoid biosynthesis. Down-regulated DEGs were enriched for genes involved in translation. Validation of selected genes on pistil tissue of the 26 single genotypes revealed that differences between bulks could both be due to a general trend of the bulk or to the behaviour of single genotypes. Novel candidate genes potentially involved in the control of stigma position in tomato are discussed.

The article provides data on the need for leading countries to move to building bioeconomics, the role of the forest sector and the productivity of trees for this purpose, the characteristics of the birch gene pool available at the objects of a single Genetic and Selection Complex in the Central black earth Region of the Russian Federation, and the overcoming of non-crossing in fast-growing tree species. The characteristic of the birch tree as a convenient model object for genetic, selection, morphological, and biochemical research is given. The safety and productivity characteristics in different periods of ontogenesis in birch species and hybrids were studied, and a selection inventory of test birch crops was carried out. The General scheme of the selection process used for obtaining valuable genotypes for their mass reproduction, methods of selfing and hybridization of birch trees, and a sequence diagram of steps for obtaining adaptive planting material of fast growing woody plants (ante vitro, in vitro, ex vitro), the importance of each stage in the process. In conclusion, conclusions are given based on the results of the study, among which there are indications of the species specifics of the studied birches, both local and introduced. We also identified drought-resistant and, consequently, promising birch families of different genetic origin for reforestation.

An adequate nutritional management is essential to ensure high coffee yields. In view of the wide genetic variability among Coffea canephora genotypes, due to the allogamy of the species, the nutri...

The floral morphology and pollination of S. guineense subsp. macrocarpum were investigated on ten trees selected for a study of floral phenophases in the natural forest of Bassila, located in the Sudano-Guinean zone (Benin). For the floral analysis, the two stages considered were flower buds for preflowering data and open flowers for flower data. To determine the pollination mode and identify main pollinators, two stages were considered, namely flower bud and initiated fruits. The fruit set, autogamy and allogamy rate were assessed. Results show that several flower morphological traits predispose this species to selfing and cross pollination, including hermaphroditism and a long anther–stigma distance. The symmetry is actinomorphic with a floral receptacle adnate to the ovary. The latter is inferior, bicarpellary and bilocular syncarpous and contains 18–22 ovules on an axile placenta. Only a single ovule is fertilized and becomes a seed. Visitors frequently registered on the flowers of S. guineense subsp. macrocarpum are exclusively insects belonging to six orders, including Diptera (26%), Hymenoptera (24%), Lepidoptera (19%). The mean fruit set was 0.47 ± 0.10 for the open-pollination experiments and 0.27 ± 0.12 for autogamous self-pollination. The autogamy rate was 57.45% and the allogamy rate 42.55%. This study confirms that S. guineense subsp. macrocarpum is predominantly autogamous. Self-compatibility is not for exceptional species, but a dominant characteristic of the genus Syzygium. The viability of the pollen grains and receptivity of the stigma at each flowering stage should be further studied.

The Cactaceae display a wide array of pollination systems, with many different animals already confirmed as pollinators. Pilosocereus is one of the most conspicuous bat-pollinated genera characteristic of the tropical dry forests of Brazil, known as Caatinga. The role of bats, hawkmoths and bees as pollinators in natural populations was investigated for four Pilosocereus species (P. catingicola, P. chrysostele, P. gounellei and P. pachycladus). Earlier results obtained with P. tuberculatus were also included in the comparative discussion. These species depend mainly upon nocturnal visitors; however, Xylocopa grisescens bees also play a secondary role in the fruit set. Although chiropterophily is predominant in Pilosocereus, P. gounellei was visited and pollinated at night exclusively by sphingids. All species are described as presenting a chiropterophilous syndrome based on their nocturnal anthesis, strong and unpleasant flower scent, pale, white or cream inner perianth, compact and abundant flower parts, and large volume of nectar with low sugar concentration. Pollen is available and the stigma is receptive throughout anthesis. With the exception of P. gounellei, there was no fruit set from spontaneous or manual self-pollination, indicating that allogamy is the predominant reproductive system in all the species studied. These species thus rely on animals that function as efficient pollen vectors for their sexual reproduction. The Pilosocereus species present different levels of dependence on bats, from the participation of secondary pollinators to not being visited by bats at all. Dependence levels are associated with the species floral attributes, which, although subdued, can determine different pollination systems.

Euterpe precatoria (Acai-do-Amazonas) produces fruits of which the fresh pulp is consumed. It is almost exclusively collected by extractivist farmers, because no selected genotypes are available for the establishment of plantations. For the domestication and breeding of the species, mating system studies are needed for strategy formulation. This study evaluated the mating system of a natural population of E. precatoria. Thirteen progenies were genotyped with 13 microsatellite loci by capillary electrophoresis in an automated DNA sequencer. Estimates of single-locus and multilocus outcrossing rates were 1.0, and paternity correlation was low (r^p(m)>= 0.293). Euterpe precatoria families consist mainly of half-sibs and the reproductive strategy of the species is allogamy.

Cultivated yam (D. rotundata) is a staple tuber crop in West Africa whose sexual reproduction control remains largely unknown despite its importance for plant breeding programs. In this paper, we compared self-pollination, intracultivar cross-pollination and intercultivar cross-pollination in three monoecious cultivars (Amoula, Heapala and Yassi). Results showed that pollen viability (49%) and stigma receptivity (40%) were similar in monoecious and dioecious plants, suggesting that autogamy could occur in monoecious plants. However, fruit and seed sets were significantly lower after self-pollination compared to cross-pollination. Overall, autogamy reached 11% and pollen lability was almost zero (

Rosemary, a well-known Mediterranean aromatic evergreen, up to 3-m-high perennial shrub, is widely cultivated since ancient times for medicinal, culinary and ornamental purposes. The Mediterranean genus Rosmarinus L. (Lamiaceae) includes three species; among them the most common and most widely distributed is Rosmarinus officinalis L. “The dew of the sea” (the meaning of rosemary) with small white, pink to bluish hermaphrodite flowers can grow and reproduce under diverse climate and soil conditions. It can be found in an abundant morphological and biochemical variation (e.g. growth habit, leaf size, flower size and colour, volatile compounds). This variation can be explained by high phenotypic plasticity and genetic diversity within and among populations. Self-compatibility is predominant in rosemary breeding system, but automatic self-pollination is prevented by strong protandry in combination with nonsimultaneous maturation of anthers and stigma. The proportion of male-sterile flowers in R. officinalis shows large temporal variation during the breeding season. This temporal gynodioecy, the length of the flowering season and flowering synchrony of individuals within populations all favour high rates of cross-pollination, therefore increasing allogamy rates.

The numbers of disk floret anthers of Calyptocarpus vialis in Wichita County, Texas form a consecutive series of one to four; four anthers (71%) and three anthers (27%) were most common. Three anthers is an unusual, perhaps singular, number for Asteraceae. These florets also have four-lobed corollas. The extruded pollen-mass is enclosed by a vaulted dome created by apical appendages of the anthers that are lanceolate and inflexed. Pollination appears to be via autogamy ( sensu stricto ) for disk florets and (considering each head as a single blossom) facultative autogamy and allogamy (both geitonogamy and xenogamy) for the ray florets.

Floral monosymmetry appears to be a derived condition, arising independently many times, with a multiplicity of forms, and related to both, pollinator and plant diversification. It reduces interference between sexual functions in flowers and increases cross-pollination and allogamy. But since the description and assessment of the functioning of those floral features depend on fresh material and field observations, the number of groups thoroughly observed is limited. In the mostly Neotropical and actinomorphic Melastomataceae, monosymmetric flowers seem to be derived and the resulting herkogamy may constitute a mechanism to avoid anther–stigma interference and self-pollination. Here we studied Tococa guianensis, a Neotropical widespread shrub or treelet well known for its leaf–domatia ant interaction, but still lacking details on its breeding biology. We studied a population in Uberlândia, Central Brazil, observing floral biology features, diversity of visitors and breeding system. Flowers showed diurnal anthesis and a single-day life span. Pollen was the only floral resource offered, and poricidal anthers were clustered in the centre of the flower, while style was bent away from flower axis creating a transient herkogamy and flower monosymmetry. Style moves towards the floral axis during the day facilitating pollination. To date we do not know other Tococa species displaying such stylar features, which may be an intermediate form between the actinomorphic Miconieae and specialized zygomorphic Tococa. Contrasting with previous studies, the self-incompatibility found in T. guianensis indicates that transient herkogamy may function to avoid stigma clogging with self-pollen and allow flexible use of specialized buzz-pollinating bees.

The study of pollen dispersal and mode of fertilization of Vernonia amygdalina and Vernonia calvoana is a prerequisite to the understanding of genetic diversity and elaboration of improvement programs for the Vernonia genus. In this study, precise experimental designs were made for morphological and biological observations on Vernonia species capitulum in order to assess the distinctive effects of each of the three possible pollen transportation agents (insects, wind and rain water) on pollination. Results obtained show that the exclusive mode of pollen dispersal is entomophilous. Even though allogamy and autogamy are observed as two possible modes of fertilization in Vernonia spp., some arguments tend to favour allogamy. However, there is no clear cut position on the issue, hence the need for confirmation by further experimentation in controlled pollination. This study paves the way for the establishment of a genetic improvement program for this genus based on the results on pollen dispersal. Key words: Vernonia species, allogamy, autogamy, pollination agent.

The (scarlet) runner bean ( Phaseolus coccineus L.; 2 n = 2 x = 22) is an allogamous legume species from Mesoamerica that is cultivated as an annual crop for dry seeds and immature green pods in several parts of the world. It is grown especially in small-scale agriculture. From an agronomic perspective, it is predominantly indeterminate and climbing type of growth is associated with high labor and materials required to grow the crop with support structures. Intercropping (i.e., maize-runner bean) and seed inoculation using bio-compounds (i.e., rhizobacteria) have resulted in more efficient resource utilization, reduced risk to the environment and diminished production costs, which are valuable practices linked to sustainable agriculture. Cold tolerance and hive management due to allogamy are also distinctive features of runner bean production that have been studied. From a genomic standpoint, runner bean has been very little studied, despite the abundant development of molecular markers and genome sequencing of other legumes in the last decade, and more specifically common bean ( P. vulgaris ). The high genetic variability of runner bean is precious for breeding purposes, particularly as a source of disease resistance and cold tolerance. However, the lack of characterization of the P. coccineus germplasm restricts its utilization as donor species for inter-specific hybridization, and consequently limits its use in other Phaseolus breeding programs (i.e., common bean). Developing more broadly adapted, determinate cultivars that facilitate mechanical harvesting, assessing the potential presence of heterosis for hybrid seed production, and characterizing the germplasm of P. coccineus more extensively are great challenges and opportunities in the future that would increase its cultivation on a broader scale worldwide.

Standing genetic variation is considered a major contributor to the adaptive potential of species. The low heritable genetic variation observed in self-fertilising populations has led to the hypothesis that species with this mating system would be less likely to adapt. However, a non-negligible amount of cryptic genetic variation for polygenic traits, accumulated through negative linkage disequilibrium, could prove to be an important source of standing variation in self-fertilising species. To test this hypothesis we simulated populations under stabilizing selection subjected to an environmental change. We demonstrate that, when the mutation rate is high (but realistic), selfing populations are better able to store genetic variance than outcrossing populations through genetic associations, notably due to the reduced effective recombination rate associated with predominant selfing. Following an environmental shift, this diversity can be partially remobilized, which increases the additive variance and adaptive potential of predominantly (but not completely) selfing populations. In such conditions, despite initially lower observed genetic variance, selfing populations adapt as readily as outcrossing ones within a few generations. For low mutation rates, purifying selection impedes the storage of diversity through genetic associations, in which case, as previously predicted, the lower genetic variance of selfing populations results in lower adaptability compared to their outcrossing counterparts. The population size and the mutation rate are the main parameters to consider, as they are the best predictors of the amount of stored diversity in selfing populations. Our results and their impact on our knowledge of adaptation under high selfing rates are discussed.

This work aimed at exploring the genetic variability, population structure and relationships of Lathyrus sativus L. germplasm using isozyme analysis. The data of isozyme analysis revealed 12 putative polymorphic loci of a total 33 alleles, indicating that studied accessions express good allelic richness and had an apparent rate of allogamy. The mean average of the expected heterozygosity (0.483) was more than the mean average of the observed heterozygosity (0.449) suggesting an apparent rate of allogamy taking place in Lathyrus sativus L. The average of total heterozygosity (HT) and intra-accessional genetic diversity (HS) were 0.559 and 0.428 respectively indicating that majority of genetic diversity was intra-accessional. The low levels and non-significant of genetic diversity among accessions (DST = 0.190, X2 = 62.59, p = 0.029) were probably indicative of occurrence of several gene flows. The coefficient of gene differentiation (GST) showed significant variation, suggesting the heterogonous distribution of L. sativus accessions among different geographic regions. The mean average of FST was 0.327, suggesting the occurrence of random mating system for the studied accessions and reflecting adaptation to strong environmental dissimilarities. Cluster analysis based on isozyme data suggested that the environment had no influence on the genetic diversity and confirmed that Lathyrus sativus L. had a polyphyletic origin.

Background and Aims The terrestrial orchid genus Epipactis has become a model system for the study of speciation via transitions from allogamy to autogamy, but close phylogenetic relationships have proven difficult to resolve through Sanger sequencing. Methods We analysed with restriction site-associated sequencing (RAD-seq) 108 plants representing 29 named taxa that together span the genus, focusing on section Epipactis. Our filtered matrix of 12 543 single nucleotide polymorphisms was used to generate an unrooted network and a rooted, well-supported likelihood tree. We further inferred genetic structure through a co-ancestry heat map and admixture analysis, and estimated inbreeding coefficients per sample. Key Results The 27 named taxa of the ingroup were resolved as 11 genuine, geographically widespread species: four dominantly allogamous and seven dominantly autogamous. A single comparatively allogamous species, E. helleborine, is the direct ancestor of most of the remaining species, though one of the derived autogams has generated one further autogamous species. An assessment of shared ancestry suggested only sporadic hybridization between the re-circumscribed species. Taxa with the greatest inclination towards autogamy show less, if any, admixture, whereas the gene pools of more allogamous species contain a mixture alleles found in the autogams. Conclusions This clade is presently undergoing an evolutionary radiation driven by a wide spectrum of genotypic, phenotypic and environmental factors. Epipactis helleborine has also frequently generated many local variants showing inclinations toward autogamy (and occasionally cleistogamy), best viewed as incipient speciation from within the genetic background provided by E. helleborine, which thus becomes an example of a convincingly paraphyletic species. Autogams are often as widespread and ecologically successful as allogams.

Flower timing studies in June and July (1972) on populations of Sabatia campestris Nutt. show this plant to be allogamous (out crossing) under natural field conditions. However, when environmental factors reduce populations of solitary bees or when flower populations are particularly extensive and dense, the uncollected pollen causes retention of anthers into the period of style opening and stigma presentation. Then autogamy (self-pollination) occurs. Pollinators observed were solitary bees in the genera Calliopsis, Dialictus , and infrequently Augochlorella . Pollen viability is generally excellent. A chromosomal count of n=12 indicated the presence of aneuploid races in this plant species. The lengthening of petals from anthesis to wilting and calyx from bud to fruit production indicates flower size cannot be used as a taxonomic character to separate species.

Deschampsia antarctica3 E. Desv. is one of the two flowering plants that, along with Colobanthus quitensis (Kunth) Bartl., was able to settle the ice-free areas of Antarctica. In order to identify the possible adaptations of the D. antarctica reproductive system to adverse environmental conditions, comparative cytoembryological analysis of plants of this species growing on the Antarctic Peninsula with plants of the closely related species D. beringensis Hult. from the Kamchatka Peninsula was conducted. It was found that both species are characterized by sexual mode of reproduction, equal size of pollen grains (25.5 ± 2.2 and 26.2 ± 1.9 μm, respectively), same features of the embryo sac structure, and emryo- and endospermogenesis. Interspecies differences have been found in mature embryo sac size (326.8 ± 12.8 and 161.7 ± 10.4 μm), pollen sterility percentage (86.1 ± 8.9 and 35.3 ± 9.2%), and quantity of pollen in the anthers (140 ± 15.3 and 1578 ± 88.6). Possible causes and significance of these differences are discussed. No unique adaptations of seed reproduction system that are inherent exclusively to D. antarctica were found. The D. antarctica reproduction strategy is based on the combination of autogamy (and its extreme form cleistogamy) with production of excess pollen quantity for its mode of pollination.

Conilon coffee is a highly heterozygous diploid plant that is also allogamous, producing seeds through cross-fertilisation. Due to their allogamy, plants of seminiferous origin are highly heterogeneous, exhibiting high morphological and genetic diversity. However, propagation through cutting guarantees the maximum homogeneity of fields, particularly in grain maturation, among other desirable characteristics. Currently, the majority of commercial Conilon coffee is planted using seedlings propagated by cuttings. Studying the juvenile behaviour of different clonal genotypes of the Conilon coffee plant represents an important tool to assist with the establishment of this crop. The objective of this study was to assess the growth, development and genetic diversit y in several promising genotypes of the Conilon coffee plant based on the morphological characteristics of seedlings propagated by cutting. We used seedlings Conilon coffee of 33 genotypes selected by coffee growers, and with great productive potential, and genotype 02 of the Emcapa 8111 variety. Based on morphological characteristics linked to the growth and development of the aboveground and root systems of the genotypes, their phenotypic correlations were estimated, along with the genetic diversity among genotypes, using Tocher’s optimisation method and the unweighted peer group method with arithmetic mean. Genotypes A1, P2, Z39, Ouro Negro, Tardio C, Cheique, and Z29 exhibited a higher Dickson quality index (between 0.40 and 0.56). Genetic variability exists among the seedlings of the 34 genotypes of Conilon coffee studied. The most dissimilar genotypes were CHR, 18, and Z39, which remained in isolated groups in all experiments.

Genetic diversity within and among 50 populations of confectionery sunflower (Helianthus annuus L.) collected from different geographical areas of Iran was evaluated by using microsatellite and retrotransposon markers. The number of alleles (Na) in SSR loci ranged from 2 to 3 with an average of 2.1. The polymorphic bands in retrotransposon markers ranged from 7 in locus CR-UR1 to 15 in locus CR-816 with a mean value of 11.33. Herarchical clustering of individuals (50 × 5 = 250) by neighbor joining method in DARwin5 software subdivided them into three groups. Using Bayesian method in the software pakage of Structure, the studied individuals were subdivided into two sub-populations. Principal coordinate analysis revelaed that the two first components explaine 7.86 and 6.16% of the total variance, respectively. Analysis of molecular variance revealed a higher level of genetic variation within (70%) than between (30%) populations. High molecular variation among individuals within population possibly is due to high allogamy nature of the sunflower plant. Low genetic variation observed between populations could be considered as a consequence of genetic equilibrium that has occurred over the long period of cultivation of confectionery sunflower in this area as well as seed exchange among regions. The traditional assumption that selecting genotypes of different geographical origin will maximize the diversity available to a breeding project does not hold in confectionery sunflower.

O objetivo deste estudo foi avaliar o sistema de fecundação e a distribuição da variabilidade molecular entre e dentro de três grupos de progênies de polinização aberta de Euterpe oleracea, além de realizar um teste de paternidade para identificação dos genitores masculinos e promover a certificação genética das plântulas bífolioladas. Para tal, foram utilizados seis loci microssatélites em 306 amostras. Os grupos de progênies são resultado de um sistema misto de fecundação, com ausência de cruzamentos entre aparentados, sendo alógamos (tm e ts = 1,0), com correlação de autofecundação (rt) igual a 0,110. Foram constatados diferentes graus de parentescos (rp), entre 15,5 a 26,1% de irmãos completos. A paternidade foi atribuída para 51% e 24% das amostras, com 80 e 95% de confiança respectivamente. Foram identificados 22 doadores de pólen e uma autofecundação, verificou-se que o morfotipo bífoliolado não é garantia de cruzamento intraespecifico, já que quatro progênies foram identificadas como híbridos interespecíficos. Foram detectados em média 7 a 12,3 alelos por locus e uma heterozigosidade média observada entre 0,382 a 0,898 e a esperada entre 0,354 a 0,693. O índice de fixação foi entre -0,053 a -0,319. A variação entre os grupos foi de 5%, sendo 95% dentro deles. Os resultados indicam boas perspectivas para realização de trabalhos futuros relacionados à predição de ganhos genéticos a partir da seleção entre e dentro dos grupos de progênies., The objectives of this study were to analyze the mating system and the distribution of molecular variability among and within three groups of open pollinated progenies of Euterpe oleracea, in addition to performing a paternity test to identify the male parents and to further the genetic certification of the bifoliolate seedlings. With this purpose, we applied six microsatellite loci markers to 306 samples. The progeny groups are the result of a mixed breeding system, with no crosses between relatives, with allogamy (tm and ts = 1), and self-fertilization correlation (rt) of 0.110. Different degrees of kinship were found (rp), with complete siblings between 15.5 a 26,1%. Paternity was assigned to 51% and 24% of the samples with 80 % and 95% confidence, respectively. Twenty-two pollen donors and one self-fertilization were identified. We also found that the bifoliolate morphotype does not assure the occurrence of intraspecific crosses, since four progenies were identified as interspecific hybrids. A mean from 7 a 12.3 to alleles per locus was detected. The average heterozygosity was observed between 0.382 and 0.898 and the expected heterozygosity between 0.354 and 0.693. The fixation index was estimated between -0.053 and - 0.319. The variation between groups was 5% and within groups was 95%. The results indicate good prospects for future work related to the prediction of genetic gains from the selection among and within the progeny groups., Facultad de Ciencias Agrarias y Forestales

The gambier plant pollination system needs to be understood for a breeding program to be conducted. The purpose of this study was to determine the percentage of self-pollination [autogamy and geitonogamy] and cross-pollination, both natural and artificial allogamy, in these plants. This research was conducted in the Experimental Garden of the Faculty of Agriculture, Andalas University, Padang and used a survey method [identifying samples, conducting pollination, observing samples and collecting data obtained in the field] together with non-probabilistic purposive sampling. Observations made include pollen adhesion to the stigma and fruit formation. Data were analyzed using simple statistics. Fruit production was highest following artificial allogamous cross-pollination [86%], followed by natural allogamous cross-pollination [51%] and geitonogic self-pollination [22%]. Autogamic self-pollination failed to produce fruit. Gambier plants are cross-pollinating plants able to undergo geitonogamous but not autogamous self-pollination.

In search of causal factors underlying perceived allogamy in sunnhemp (Crotalaria juncea L.), we investigated the breeding system and pollen–pistil interaction. Floral biology study in the species established Fabaceae type hermaphrodite zygomorphic flower with dimorphic anthers. Study of the breeding system revealed preferential success of allogamy despite delayed autonomous selfing mechanism characteristically prevailing in the species. Pollen–pistil interaction study in selfed and crossed pistils revealed significant differences in pollen tube growth rates inside the pistil. Further, in self-pollinated pistils callose formation observed at and around nucellus cells suggesting the late-acting type of self-incompatibility mechanism in the species. To the best of our knowledge, this is the first scientific communication underscoring the prevalence of self-incompatibility mechanism in sunnhemp.

Previous studies have shown that levels of genetic diversity in species of the genus Cephalanthera covary with the breeding system. In the southern part of the Korean Peninsula, the three self‐compatible terrestrial orchids Cephalanthera erecta, C. falcata and C. longibracteata flower synchronously in sympatric populations. The food‐deceptive C. falcata with bright yellow flowers is predominantly outcrossing, whereas autogamy is the dominant strategy in both C. erecta and C. longibracteata, whose white flowers do not open fully. We examined genetic diversity (by means of allozymes) of the three species in sympatric populations (600 × 600 m area) in the Yeonwhasan Provincial Park (YPP) and in non‐sympatric populations outside YPP, South Korea. Thirteen out of 20 putative loci were variable across the three species, but there was a complete lack of allozyme variation within each species and we found no evidence of hybridisation. Our results suggest that historical factors, i.e. the Quaternary climate oscillations, have played a major role in determining levels of genetic diversity in the three Cephalanthera species. The Korean populations of C. erecta (a warm‐temperate/temperate element) and C. falcata (a warm‐temperate element) may have been established by a single introduction from a genetically depauperate ancestral population, likely located outside the Korean Peninsula. On the other hand, since C. longibracteata is a boreal/temperate element, it may have survived the Last Glacial Maximum in microrefugia located in low elevation regions within the Peninsula where it has been subjected to population bottlenecks reducing its genetic diversity., This research was supported by a Korea Research Foundation grants; NRF‐2013R1A1A2063524 to MYC and NRF‐2013R1A1A3010892 and NRF‐2017R1A2B4012215 to MGC.

Faba bean ischeapest sources of protein and other nutrients including minerals, cool season legume crop. To know the magnitude of cross-pollination, an experiment was conducted with seven genotypes, under control/self and open-pollinated condition at ICAR Research Complex for Eastern Region Patna during cool seasons 2016-17. Experiments on faba bean are being regularly conducting since thecool season of 2007-08. Results revealed that seed yield and yield attributing traits has been reduced under thecontrolled/self-pollinating condition as compare to open/cross-pollinated condition, though the reduction was not same for all tested genotypes. The magnitude of yield reduction was in the range of 13.3 to 41.7 percent. Harvest Index was also gets diminished from maximum 49.2 to 21.7% with reduction of minimum 37.8 % to maximum 50.7%. It was also observed that honey bee (Apismellifera)was the major pollinator bee. Results clearly indicate that apoides play a decisive role in therealization of potential yield by the cross-pollination mechanism of allogamesfaba bean.

Self‐pollination by geitonogamy is likely in self‐compatible plants that simultaneously expose a large number of flowers to pollinators. However, progeny of these plants is often highly allogamous. Although mechanisms to increase cross‐pollination have been identified and studied, their relative importance has rarely been addressed simultaneously in plant populations. We used Rosmarinus officinalis to explore factors that influence the probability of self‐fertilisation due to geitonogamy or that purge its consequences, focusing on their effects on seed germination and allogamy rate. We experimentally tested the effect of geitonogamy on the proportion of filled seeds and how it influences germination rate. During two field seasons, we studied how life history and flowering traits of individuals influence seed germination and allogamy rates of their progeny in wild populations at the extremes of the altitudinal range. The traits considered were plant size, population density, duration of the flowering season, number of open flowers, flowering synchrony among individuals within populations and proportion of male‐sterile flowers. We found that most seeds obtained experimentally from self‐pollination were apparently healthy but empty, and that the proportion of filled seeds drove the differences in germination rate between self‐ and cross‐pollination experiments. Plants from wild populations consistently had low germination rate and high rate of allogamy, as determined with microsatellites. Germination rate related positively to the length of the flowering season, flowering synchrony and the ratio of male‐sterile flowers, whereas the rate of allogamous seedlings was positively related only to the ratio of male‐sterile flowers. Rosemary plants purge most of the inbreeding caused by its pollination system by aborting the seeds. This study showed that the rates of seed germination and allogamy of the seedlings depend on a complex combination of factors that vary in space and time. Male sterility of flowers, length of the flowering season and flowering synchrony of individuals within populations all favour high rates of cross‐pollination, therefore increasing germination and allogamy rates. Flowering traits appear to be highly plastic and respond to local and seasonal conditions., Financial support was provided by CGL2009‐07262/BOS project from the Spanish Ministry of Science and Innovation (MICINN) and PROMETEO/2016/021 project from the Valencia Autonomous Government. J.G.S.‐M. was supported by a ‘Ramón y Cajal’ post‐doctoral contract from MICINN. M.C.C. was supported by a JAE‐Doc CSIC post‐doctoral scholarship.

We studied the significance of sexual reproduction as a source of ploidy level variation in a model system consisting of hexaploid, facultatively apomictic Pilosella bauhini and tetraploid, sexual P. officinarum. As the maternal parent, apomictic P. bauhini generated higher ploidy level variation than sexual P. officinarum. Ploidy levels of its progeny ranged from triploid to octoploid under experimental conditions and even to decaploid in the field. This progeny diversity resulted from the breeding system in P. bauhini, which included haploid parthenogenesis and sexual reproduction through both reduced and unreduced gametes besides prevailing apomixis; these particular reproductive pathways have been quantified. Sexual P. officinarum, on the other hand, reproduced exclusively through fusion of reduced gametes and produced only pentaploid hybrids or tetraploid progeny from autogamy, allogamy or both. Surprisingly, sexual P. officinarum was also the species showing stronger reproductive isolation, especially under the field conditions where intra-specific fertilization was highly favoured, most probably through competition between conspecific and heterospecific pollen. Apomictic P. bauhini thus appeared to be a significant source of ploidy level variation in the model population even though most of its progeny was formed clonally through apomixis. Only part of this variation was manifested in the field.

Cichorium intybus L., well known in Italy with the common name &ldquo, Radicchio&rdquo, is an important leafy vegetable that is prevalently reproduced by allogamy due to very efficient barriers of self-incompatibility. Marker-assisted breeding is widely used by seed firms to develop new hybrid varieties that manifest genetic distinctiveness, uniformity and stability. A total of 29 mapped microsatellite markers were used for genotyping 504 samples of the Red of Chioggia biotype: First, two synthetics, four F1 hybrids and two derived F2 populations were compared to assess the distinctiveness of their gene pool and structure, then, the uniformity and stability of 3 years of production of a commercial F1 variety were also investigated. Genetic similarity and diversity statistics as well as the genetic structure of populations were analysed, including allele and genotype frequencies. The mean estimates and ranges of genetic similarity enabled the molecular discrimination of OP synthetics from F1 varieties and their F2 progenies and the determination of individual plant memberships. Moreover, the genetic structure of F1 hybrids produced in 3 years unexpectedly revealed two main clusters that discriminate the first 2 years from the 3rd, mainly because of the presence of uncommon specific alleles and different allele frequencies. Overall, this molecular information will enable breeders to determine the genetic distinctness, uniformity and stability of commercial and experimental varieties, as well as their genetic relationships and relatedness. Hence, this work provides a useful tool for achieving the molecular characterisation and genetic identification of different radicchio populations.

Clonal propagation and sexual reproduction have diametrically opposite effects on the genetic diversity of crops, permitting, respectively, the conservation of existing genotypes or the creation of new diversity. Oxalis tuberosa Mol. (‘‘oca’’) exhibits a heteromorphic selfincompatibility system and is traditionally propagated clonally but is capable of sexual reproduction. In this study we investigated the influence of sexual reproduction on the in situ genetic diversity of a vegetatively propagated crop, taking oca as a model plant. The occurrence of sexual reproduction in natural conditions and its use by farmers were studied through surveys and interviews, while the effect of sexual reproduction on the in situ genetic diversity was evaluated using microsatellite analysis. Plantlets issuing from sexual reproduction were encountered in five of the nine visited communities. The interviews indicated that six out of the nine interviewed farmers were likely, albeit unconsciously, incorporating clonal lineages issuing from sexual reproduction into their varieties. The microsatellite analysis indicated a strong effect of such incorporations on the genetic diversity of the plant varieties. Assignment tests confirmed the allogamy of oca. ‘‘Complex varieties’’, made up of individuals exhibiting genetically differentiated genotypes,weremost likely the result of recent crossing. Unconscious incorporation of newgenotypes into the cultivated oca germplasm is therefore highly likely, raising the question of its potential occurrence in other vegetatively propagated crops. These findings could have an important effect on the adaptive potential of oca, especially in light of the genetic erosion that threatens the crop

Many rare plants exist in a naturally fragmented distribution and are expected to exhibit reproductive adaptations to isolation. Thus, understanding the reproduction of these plants might be important in predicting the future of artificially fragmented species. Ameroglossum pernambucense is a threatened ornithophilous shrub with naturally fragmented populations on granite outcrops in north-eastern Brazil. The current research studied two populations of A. pernambucense and determined if three reproductive features (mating system, flowering phenology and nectar dynamics) facilitate the colonisation of new areas and the gene flow among the outcrops. To verify the species’ reproductive efficiency, pollinator efficiency and pollen limitation were tested. Ameroglossum pernambucense has a mixed mating system, and pollinators increased seed production. The pollinator efficiency test revealed that hummingbirds can supply the entire pollen demand. No pollen limitation was detected. Variation in sunset time was the main factor to explain the flowering pattern of A. pernambucense. Nectar was abundantly produced after successive removals. The reproductive traits observed in A. pernambucense were interpreted as highly adapted to its fragmented condition. Phenological photoperiodic regulation may increase the flowering synchrony and chances of gene flow among outcrops in environmentally distinct microsites. The mixed mating system favours both the colonisation of isolated outcrops and allogamy. High flower production and its high energetic value may have an important role in pollinator attraction and may increase long-distance outcrossing. Our data suggest that artificially fragmented plants with reproductive features similar to those observed here might be reproductively less susceptible to fragmentation.

Common lambsquarters is highly competitive in many cropping systems and has demonstrated resistance to several herbicide mechanisms of action. However, predicting the spread of resistance is difficult due to limited information about gene flow. We conducted research to determine the potential for movement of resistance alleles in common lambsquarters under field conditions.Chenopodium giganteum(a member of theC. albumaggregate) that has a dominant magenta phenotypic marker was used as a pollen parent in gene flow experiments. A wild-type accession of common lambsquarters was used as a seed parent. Seed parents were grown in a soybean field and arranged in concentric circles 2 to 15 m from a center which contained 24 pollen parents. The concentric circles were divided into eight directions. Pollen movement was estimated by determining the percentage of progeny with the magenta phenotype from seed parents. Average cross-pollination across directions was greatest (3.0%) at 2 m and decreased to low levels (0.16%) 15 m from the center, consistent with observations of other primarily self-pollinated species. Cross-pollination was greatest (P < 0.10) in the south-southwest, west-southwest, and west-northwest directions, approximately 180° from the prevailing wind direction during the time of pollen shed. Since common lambsquarters does not have an active dispersal mechanism for seeds, pollen-mediated gene flow may play an important role in the transfer and frequency of resistance alleles within and between populations.

Forage quality combines traits related to protein content and energy value. High-quality forages contribute to increase farm autonomy by reducing the use of energy or protein-rich supplements. Genetic analyses in forage legume species are complex because of their tetraploidy and allogamy. Indeed, no genetic studies of quality have been published at the molecular level on these species. Nonetheless, mapping populations of the model species M. truncatula can be used to detect QTL for forage quality. Here, we studied a crossing design involving four connected populations of M. truncatula. Each population was composed of ca. 200 recombinant inbred lines (RIL). We sought population-specific QTL and QTL explaining the whole design variation. We grew parents and RIL in a greenhouse for 2 or 3 seasons and analysed plants for chemical composition of vegetative organs (protein content, digestibility, leaf-to-stem ratio) and stem histology (stem cross-section area, tissue proportions). Over the four populations and all the traits, QTL were found on all chromosomes. Among these QTL, only four genomic regions, on chromosomes 1, 3, 7 and 8, contributed to explaining the variations in the whole crossing design. Surprisingly, we found that quality QTL were located in the same genomic regions as morphological QTL. We thus confirmed the quantitative inheritance of quality traits and tight relationships between quality and morphology. Our findings could be explained by a co-location of genes involved in quality and morphology. This study will help to detect candidate genes involved in quantitative variation for quality in forage legume species.

Periwinkle (Catharanthus roseus (L.) G. Don), an important medicinal plant, is an allogamous species in which the stigma is below the anthers. The receptive portion is at the base of the stigmatic head and thus automatic intra-flower self-pollination is excluded. The structure of the flower is of typical reverse herkogamy and pollination occurs through nectar-seeking insects. A few self-pollinating strains are also reported in which self-pollination is brought about by an increase in length of the style or of the ovary. Self-pollination is governed by allelic duplicate genes recessive to allogamy. An induced monogenic reces- sive mutant (EMS 17-1) with caducous closed corolla (corolla abscising before anthesis), isolated from variety, Dhawal, was crossed with two self-pollinating strains to study the possibility of obtaining cleistogamous recombinants combining closed corolla and self-pollination traits. Cleistogamous plants were obtained in which development of fruits and seeds occurred without opening of the corolla. Closed corolla and self-pollination were found to be independently inherited. A dominant g ene in the parent in which self-pollination occurred due to an increase in length of the ovary, appeared to completely or partially inhibit expression of the gene for closed corolla in homozygous or heterozygous condition, respectively. The genetic basis of development of cleistogamy is described. Cleistogamy in periwinkle would facilitate in ensuring genetic purity, pollen containment, and seed production even in the absence of pollinators. This appears to be the first report on the development of cleistogamous plants in an allogamous species.

The flowers of Marantaceae (∼ 550 species) exhibit a highly derived pollination mechanism within Zingiberales, with a rapid and irreversible style movement based on a close synorganization of different floral parts. Given the complexity of the structure, we assume that little variation is possible if functionality is to be maintained. To test this, we investigated how much floral diversity exists in the clade and whether this diversity potentially influences the breeding system and placement of pollen on the pollinator. Flowers of 66 species covering the five major phylogenetic clades of the family were analysed. All species are similar in their basic flower construction: the fleshy staminode forms the tunnel-shaped roof of the flower and narrows the tube with stiff swellings, and the hooded staminode holds the style under tension and narrows the flower entrance with its trigger appendage. Despite morphological diversity of the pollination apparatus, functionality is maintained by coordinated variation of the fleshy and hooded staminodes. Autogamy is usually avoided by herkogamy. However, in a few exceptions, subtle morphological changes alter the breeding system from allogamy to autogamy. Variable floral proportions allow for differential pollen deposition potentially causing mechanical isolation between sister taxa. This study clearly illustrates that structural variation is not only present in the highly synorganized flowers of Marantaceae, but that it also creates potentially new options for evolutionary diversification. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168, 300–322.

Cherimoya (Annona cherimola) is a subtropical tree crop of Andean origin whose fruit set results extremely low in farming areas outside of its natural occurrence. The lack of efficient pollinators and dichogamy are often argued to be the main constraints resulting in this low reproductive success. Herein, we describe the reproductive barriers exhibited by this crop and whether wind and insects play a role in cherimoya pollination in Spain, the main region of cultivation. A. cherimola exhibits marked protogynous dichogamy with large differences in the duration of female (around 28 h) and male (

Brassica rapa subsp. rapa L. includes three different crops: turnips (roots), turnip greens (leaves) and turnip tops (inflorescences). A collection of B. rapa subsp. rapa from north-western Spain is currently kept at 'Mision Biologica de Galicia' (a research centre of the Consejo Superior de Investigaciones Cientificas (CSIC), Spain). This collection has been characterized based on morphological and agronomical traits. A better understanding of the genetic diversity present in the collection is necessary in order to optimize its use and maintenance. The objectives of the present work were to assess the genetic diversity present in the B. rapa subsp. rapa collection, to establish genetic relationships among populations and to study the genetic structure of the collection. Eighty populations were analysed based on 18 simple sequence repeats (SSRs). Populations showed a broad range of genetic diversity, thus offering good potential for further genetic improvement. Most of the variability was found within the population level, probably due to high rates of allogamy, to migration and/or interchange of seed among local growers. Populations showed a low level of differentiation, grouping in just one cluster, and therefore they can be considered as samples of a highly variable metapopulation that can be used for B. rapa breeding programmes., This research was supported by project RF-2006-00028-00-00 and the Excma. Diputación Provincial de Pontevedra, Spain.

Recently, the introduction of GM maize in agricultural production in the EU and elsewhere has raised the issue of adventitious presence of GM seeds in conventional seed lots. Adventitious presence may occur in all arable farming, and at any step in the production of seeds or grain, or in processing of harvested product in the food/feed chain. As of today, there are no official thresholds governing the adventitious presence of GM seeds in conventional seed lots in Europe. However, it is assumed that GM admixture in seed lots could have a considerable influence on the level of adventitious presence in the non-GM harvested product. The experiments highlighted in this paper aim at the consequences of adventitious presence of GM maize seeds in conventional seed lots. It is shown for varieties belonging to the same maturity group that the final GM rate (% seeds) in the harvest product is nearly same as the initial seed admixture (% seeds). This corresponds to Hardy–Weinberg expectations. The variation depends mainly on the flowering coincidence, the site and climatic conditions. In cases where the admixed seeds are of different maturity group, the level of cross-pollination in the harvest product is reduced. Furthermore a comparison between the visual GM seed detection and real-time PCR detection was done. It is evident that the result of the real-time PCR detection method has a more variable uncertainty associated with its results than the visual seed testing method. The accuracy of prediction from % GM seed to % GM DNA depends on the reference material used for calibration curves.

A espécie ornamental Hemerocallis hybrida Hort. é uma planta herbácea perene originária da Ásia. Conduziu-se este trabalho, com o objetivo de estudar métodos artificiais de hibridação, biologia floral e o sistema reprodutivo de plantas de 'lírio-de-São-José', com vistas a gerar subsídios a programas de melhoramento genético dessa espécie ornamental. A técnica de cobertura do estigma de flores de 'lírio-de-São-José', ao invés de se cobrir toda a flor, após a realização do cruzamento artificial, proporciona maior taxa de pegamento e maturação de cápsulas de sementes (p < 0,001; Teste ² de contingência 2 x 2; correção de Yates). A antese é a melhor fenofase para realização de cruzamentos controlados, apresentando taxa de receptividade estigmática de 100%, sendo a quantidade de grãos de pólen viáveis 45% maior que na fase senescência. A espécie estudada é hermafrodita, sendo essencialmente alógama, apresentando índices de autoincompatibilidade e de autogamia iguais a zero. The ornamental species Hemerocallis hybrida Hort. is a perennial herbaceous plant originated in Asia. The objective of the present work to study the artificial methods of hybridization¸ floral biology and reproductive system of daylily plants to support genetic and breeding programs of this species. The technique of covering the stigma of daylily's flowers with aluminum paper instead of covering the whole flower after the artificial crossing, provides higher setting and maturation of seed capsules (p < 0,001; Test ² contingency 2 x 2; correction of Yates). Blooming is the best phenophase for controlled crossings with estigmatic reception of 100%, and amount of viable pollen grains of 45% higher then the phase of the senescence. The studied species is hermaphrodite, essentially allogamous, with self-incompatibility and autogamy indexes equal to zero.

With 3 figures and 4 tables Abstract At the field scale, pollen flow between adjacent fields limits the potential of coexistence of different farming production systems, especially for allogamous crops like oilseed rape whose pollen is disseminated by insects or wind. In this article, we examine the efficiency of cleistogamy in an oilseed rape line which showed between 90% and 99% of flowers closed at flowering, in limiting deposition of allo-pollen. Five trials were established, consisting of two adjacent blocks, the one sown with the cleistogamous low-erucic acid line and the other with a classically flowering high-erucic acid line, used as source of contaminating pollen, itself artificially contaminated with a 1% mix of cleistogamous plants. Analyses showed that cross-fertilization rates of cleistogamous plants, estimated through erucic acid contents of seeds collected from them, were lower than those generally observed in oilseed rape: it averaged 10.1% on isolated plants within the erucic blocks, reached to the maximum 14% immediately adjacent to the erucic block, then decreased exponentially at higher distances. Cleistogamy appeared therefore as one imperfect means of gene bio-containment.

The genus Lolium has shown a high tendency to evolve resistance to herbicides. Considering the high level of allogamy of L. perenne and the importance of the wind as an agent for pollen dispersion, the aim of this work was to assess and quantify the effective glyphosate-resistant gene flow by pollen in L. perenne under field conditions. Pollen-mediated gene flow from glyphosate-resistant to -susceptible plants was studied using a donor&ndash, receptor design. The results indicate that the effective gene flow reached trap plants distanced &le, 35 m downwind from the source of pollen. The progeny of receptor plants growing 0 m from the pollen donors showed 13% of individuals with low glyphosate sensitivity. This represents a seven-fold increase in the frequency of glyphosate-resistant individuals found in the progeny of plants isolated during the flowering period (negative control). Similarly, the progenies of plants grown at 15 and 25 m from the source of glyphosate resistance showed an increase in the frequency of resistant plants by about four- and two-fold, respectively. When the receptor plants were located at &gt, 35 m, no glyphosate-resistant plants were detected in their progenies. Management should aim for prevention or delay of flowering of glyphosate-resistant plants.

Lodicules are important organs creating the mating system in grasses, in a range between autogamy in clestogamous flowers and allogamy in chasmogamous flowers. This balance is the main factor determining variation patterns in plant populations. Recognition of variation in lodicule morphology is especially important in wheat, the main crop of the world. For this reason, a broad range of species of wheat was evaluated by means of characters showing the leafy nature of lodicules. The characters were studied under polarizing and epifluorescence microscopes. Development of lodicule stomata is different than that in leaves. Development of stomata and xylem, is distinctly correlated. Other short cells created by epidermal meristemoids are developmentally rather independent of both stomata and xylem. Interrelations between stomata, xylem and morphogenetic traits of the abaxial epidermis of the lodicule are illustrated by pictures and diagrams of numerical analyses, including a non-metric multidimensional scaling method. Some unthreshable wheats, such as Triticum diccocum, T. ispahanicum and T. spelta, have more leafy lodicules, but intraspecific variation appears in the form of +leafy vs. −leafy lodicules. Formation of leafy lodicule morphs does not depend on the ploidy level of wheat. An intraspecific mosaic of + or −leafy lodicules proves a mutational origin of their leafy characters. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 303–316.

Loquat (Eriobotrya japonica Lindl.), a member of the Rosaceae, carries the RNase-dependent gametophytic self-incompatibility fertilization system. Analysis of S-RNase-allele content in the commercial loquat cultivars Avri, Yehuda, and Akko 1 revealed that each of them contains one different S-RNase allele—S2, S3, and S4, respectively, and one that they all share, S6. Although all four S-alleles were isolated in this work, only S6 was found to be novel. Amino acid similarity between the partial sequence of S6-RNase and other known loquat RNases (S1 to S4) ranged between 62% and 65% with highest similarity (83%) to the S110-allele of European pear (Pyrus communis). Determination of S-RNase-allele content in progeny of ‘Avri’, ‘Yehuda’, and ‘Akko 1’, obtained in an open-pollinated, mixed-cultivar orchard, revealed that all of the progeny derived from self-fertilization contained the S6 haplotype, indicating that a mutation in the S6 locus is responsible for the self-fertilization. However, sequencing of most of the S6-RNase gene (from C1 to C5) did not reveal any mutation and the alignment of the deduced amino acid sequence showed that it has the expected S-RNase primary and tertiary structural organization. Nonetheless, because it is apparent that the S6-RNase allele is linked to the self-compatibility trait, it could serve as a marker for early selection of self-compatible loquat cultivars.

Creeping-rootedness (CR) is a form of vegetative propagation in lucerne (Medicago sativa L. complex) consisting of the development of new plants from adventitious shoots arising from roots with horizontal growth habit. Introgression of the CR character into cultivated lucerne may contribute to better stand persistence and greater grazing tolerance. Phenotypic selection of this trait is difficult owing to intrinsic features of the species such as autotetraploidy, allogamy and propagation by seed in addition to the polygenic control, low espressivity and variable penetrance of the trait. With the aim of developing a molecular marker-based system for the genotypic selection of the CR phenotype in lucerne, two segregating populations for this trait were screened with amplified fragment length polymorphisms (AFLPs), in order to identify CR-linked markers. Two AFLP amplicons were selected as segregating in a non-independent manner from the CR phenotype in both populations. The use of AFLP closer to the CR allows the conditional probability for CR selection to be nearly doubled. A PCR-based marker was developed for this AFLP and used to screen a collection of genotypes displaying either the CR or non-CR phenotype. The related primers were able to amplify the diagnostic amplicon in most of the CR genotypes and in approximately half of the non-CR individuals. Results are discussed in relation to the use of this marker in marker-assisted selection of the CR phenotype in lucerne.

In the course of their evolution, the angiosperms have radiated into most known plant forms and life histories. Their adaptation to a recently created habitat, the crop field, produced a novel form: the plant that allocates an unprecedented 30–60% of its net productivity to sexual structures. Long-lived trees, shrubs and vines of this form evolved, as did annual herbs. Perennial herb forms with increased allocation to asexual reproduction evolved, but there are no examples of perennial herbs with high sexual effort. We suggest that sowing seed into annually tilled fields favored shorter-lived herbs because of trade-offs between first-year seed production and relative growth rate and/or persistence. By propagating cuttings, people quickly domesticated tuber crops and large woody plants. Perennial herbs were too small to be efficiently propagated by cuttings, and the association between longevity, allogamy and genetic load made rapid domestication by sexual cycles unlikely. Perennial grain crops do not exist because they could not have evolved under the original set of conditions; however, they can be deliberately developed today through artificial phenotypic and genotypic selection.

Summary 1. Under natural selection for sexual success, the reproductive organs of plants should evolve to become highly effective pollen receptors. Among wind-pollinated plants, larger reproductive structures appear counter-adapted to accumulate pollen by impaction on their windward surfaces, because airborne particles are less able to penetrate the thicker boundary layer of larger targets. Therefore, it has been proposed that wind-pollinated plants with pollen receptors on relatively large structures, like some grasses (family Poaceae), are architecturally adapted to create downstream vortices in which airborne pollen recirculates before accumulating on leeward surfaces. From this basis, the striking diversity among the grasses in the architecture of their flowering stems has been attributed in part to the existence of these contrasting mechanisms for effecting pollen receipt, namely impact collection and recirculatory collection. 2. We investigated the relative importance of impact and recirculatory collection in grasses by analysing a model system in silico using Computational Fluid Dynamics and by conducting in vivo experiments, both in a wind tunnel and outdoors, using two grass species with compact inflorescences, Alopecurus pratensis and Anthoxanthum odoratum. 3. Irrespective of the experimental approach, we found that although pollen recirculated in the leeward eddies of inflorescences, over 95% of the accumulated pollen was collected by windward surfaces. 4. In A. pratensis, the collection efficiency (proportion of oncoming pollen collected) was between 5% and 20%, depending on wind speed in the range 0·5–1·9 m s−1 and these levels conform to those predicted by a mechanistic model of impact collection. 5. Our results demonstrate that grass species with larger inflorescences are, like those with smaller inflorescences, primarily impact collectors of airborne pollen, which suggests that dissimilar reproductive morphology among species cannot be attributed to differentiation in the mode of pollen capture and, instead, requires reference to other factors, such as the need to produce, protect and disperse seeds of different sizes in different environments.

Control of pollen dispersal is critical for the successful coexistence of genetically modified (GM) maize (Zea mays L.) and conventional maize. The impact of climate on cross-pollination by GM pollen was simulated in two field experiments with a color-recessive white-grain receptor DSP17007 and a color-dominant yellow-grain pollen donor in 2005 and 2006. The day after silk exertion of about 2500 marked single plants was taken as the basis for comparing weather data (maximum and minimum temperatures, relative humidity, wind speed, and average wind direction) with data on the cross-pollination of the white-grain receptor. Scattered significant correlations were found for all weather factors; only the minimum temperature at night had consistent negative correlations with rates of cross-pollination ranging from r = -0.22 to -0.45, indicating that the latter decreased as temperatures at night increased. In previous complementary field and growth chamber experiments, the grain set on one inbred line correlated significantly negatively with temperature up to 24 h before pollination (r = -0.55 to -0.66) because of pollen agglutination. This affects medium-distance pollen dispersals to a greater extent than short-distance ones; thus, cross-pollination with GM maize may be lower when the pollen donor has a proclivity for pollen agglutination at a high minimum temperature at night.

Partial to complete self-incompatibility is normal in most Vaccinium L. (Ericaceae) species. Wild blueberry plants of several Florida provenances and species were self- and cross-pollinated in a greenhouse free of pollinators. Fruit set of V. darrowii Camp (2x), V. corymbosum L. (4x), V. arboreum Marsh (2x), and F1 (V. darrowii × V. corymbosum) hybrids was higher after cross-pollination than after self-pollination. Partial to complete self-incompatibility was present in V. darrowii, V. corymbosum, and their tetraploid F1 hybrids. The three V. arboreum clones tested were fully self-incompatible. Intra- and interpopulation crosses in V. corymbosum, V. darrowii, and V. darrowii × V. corymbosum hybrids were highly successful, and self-pollination reduced all fertility parameters. Advanced selections of V. corymbosum were the most self-compatible clones tested, possibly because self-compatibility has been increased by breeders selecting for reliable fruit set in large fields planted with one or a few clones. One southern highbush selection and two F1 hybrids had fruit set of more than 70% after self-pollination. These plants could be potentially used to breed plants that could be planted in single blocks providing reliable yield.