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A new genus of stick insect from Jamaica is described, Jamanistria n. gen., which includes three species previously assigned to the genus Clonistria Stål, 1875, and one new species discovered by the authors in 2018, J. xerophila n. sp., described in both sexes and the egg. The previously unknown female and egg of Jamanistria annulipes (Rehn & Hebard, 1938) n. comb., male and egg of J. simplicitarsis (Gray, 1835) n. comb., female and egg of J. monticola (Rehn & Hebard, 1938) n. comb. are described here for the first time. A barcoding study based on COI gene of three species of the genus is presented and supports the species delimitations.

The geographical origin of Caribbiopheromera jamaicana Zompro, 2001, is discussed and called into question, while Clonistria caputaurata Bellanger et al., 2012, is synonymised with Bostra trinitatis Werner, 1929, which is transferred to the genus Clonistria Stål, 1875.

The egg and the adult female of Paraprisopus apterus Conle, Hennemann, Bellanger, Lelong, Jourdan & Valero, 2020, from French Guiana, are described here for the first time. Ant-mimicking morphology and behaviour of post-hatch Paraprisopus nymphs are reported and discussed.

La Guadeloupe, comme de nombreux pays de la Caraïbe, montre une très forte dépendance aux importations alimentaires. Une des alternatives consisterait à mieux connaître la richesse de nos ressources agricoles pour mieux les domestiquer et les valoriser dans notre alimentation, notre culture et nos paysages. L’agrodiversité peut prendre des formes diverses – type, nombre, agencement d’espèces - en lien avec les influences culturelles des agriculteurs ou des jardiniers, leurs finalités, et les conditions pédoclimatiques des zones d’implantation. Il devient urgent d’inventorier cette agrodiversité et d’organiser la collecte, la conservation et l’accès à la diversité en semences locales. Réseau Semences Gwada propose une démarche originale pour dynamiser de façon durable, la filière des semences en Guadeloupe. Un premier état des lieux de l’agrodiversité cultivée et cultivable a été réalisé en mettant l’accent sur la perception de la diversité et sa conservation par les acteurs concernés. Un questionnaire web a été élaboré et soumis à l’interprofession agricole, aux agro-transformateurs, à la recherche agronomique, aux associations œuvrant au profit de l’agriculture paysanne ou de l’agriculture biologique, ou encore à des groupes de discussion locaux de jardins hébergés par les médias sociaux d’internet. Nos résultats ont démontré que la tradition, le goût, la rupture avec le mode de consommation conventionnel, et l’expertise sont liés avec la diversité cultivée dans les jardins. L’utilisation pratique des plantes est structurée en niches de motivations des cultivateurs (valeur agronomique, éligibilité et propriétés médicinales). Le partage d’expertises est en attente d’une structuration pour un engagement durable. Guadeloupe, like many Caribbean countries, is very dependent on food imports. One of the alternatives would be to gain a better understanding of the richness of our agricultural resources in order to better domesticate them and make use of them in our food, our culture and our landscapes. Agrodiversity can take various forms - type, number, arrangement of species - in relation to the cultural influences of farmers or gardeners, their purposes, and the soil and climate conditions of the areas where they are planted. It is becoming urgent to inventory this agrodiversity and to organise the collection, conservation and access to local seed diversity. Réseau Semences Gwada proposes an original approach to boost the seed sector in Guadeloupe in a sustainable manner. An initial inventory of cultivated and cultivable agrodiversity was carried out, focusing on the perception of diversity and its conservation by the stakeholders. A web questionnaire was developed and submitted to the agricultural interprofession, agro-processors, agronomic research, associations working for the benefit of peasant agriculture or organic farming, and local garden discussion groups hosted by the internet social media. Our results have shown that tradition, taste, break with conventional consumption patterns, and expertise are linked to the diversity grown in gardens. The practical use of plants is structured in niches of motivations of growers (agronomic value, eligibility and medicinal properties). The sharing of expertise is waiting for structuring and a sustainable commitment.

Landscape effects might impede or increase spore dispersal and disease risk for crops, as trees and hedges buffer winds and can behave as spore traps, therefore limiting diffusion of fungi, or, on the contrary, behave as disease relay once vegetation is infected and become inoculum sources. In this study, we investigated weekly prevalence of the pathogenic fungus Colletotrichum gloeosporioides on guava tree leaves, differentiating impacts of leaf height on tree, age, and location within leaf. We first estimated differences in prevalence for each covariate, and then related infection rates to weather effects during the year. Our results highlighted a great variance of prevalence among individual trees, and a lower contamination of tree tops, as well as a tendency for greater odds of infection in tips of young leaves compared to older ones. Last, we show evidence that individual tree contaminations are associated with different disease dynamics: early and dispersal-based, late and growth-based, as well as with intermediate dynamic ranges. Pathogen infection dynamics will thus be greatly impacted by cover characteristics at local scale, and tree cover should not be perceived as homogeneously driving disease levels.

International audience; Disease perception and adequate management practices are two essential issues faced by farmers, especially in the current context of climate change which may potentially increase disease risk. We investigated the diversity of water yam cropping systems in Guadeloupe through interviews, how producers and international yam research scientists perceived anthracnose, and how this perception correlated with farmers’ risk management strategies. We found that disease perception by farmers is very close to perception by international yam experts, as both have the same perception of the hierarchy of factors translating into disease. Three different yam production strategies coexist at a local scale, where agronomic practices and socio-economic profiles are distinct and consistent with attitude toward anthracnose risk management. Six factors were perceived as decreasing the disease: associated crop species; crop rotation; staking; weeding; crop monitoring and varietal admixture. Yam producers raising crops more intensively were risk prone, while others usually sought practices to manage disease appearance and spread. Both cumulative risk and past anthracnose epidemic experiences translated into heavier reliance on chemicals. These results have practical implications for designing best yam crop management systems and control of yam anthracnose.

Grazing resistance in plants, which can be defined as the ability to grow and reproduce under grazed conditions, is either associated to defoliation avoidance or tolerance. Clonal traits are often neglected when studying functional responses to grazing, despite frequent occurrence in grassland vegetation. We investigated whether clonal traits and response to defoliation were associated to increased grazing resistance. First, grazing resistance was estimated for eight clonal species using abundance patterns in a long-term field study. We then analysed its correlation with traits in undisturbed conditions and responses to defoliation in a garden experiment. A few traits were correlated to grazing resistance, though only one was a clonal trait (belowground clonal biomass). Grazing resistance was negatively correlated to shoot height and belowground clonal biomass and positively correlated to inflorescence biomass, suggesting that tall rhizomatous species investing little in sexual reproduc- tion were at a disadvantage under grazed conditions. Both shoot height and belowground clonal biomass were negatively affected by defoliation but their decrease was significantly less for species that expressed the greatest grazing resistance in the field. Our findings show that incorporating clonal traits slightly improved predictions about field grazing resistance in the eight investigated species. Resume : La resistance au pâturage chez les plantes, que l'on peut definir comme la capacite acroitre et ase reproduire sous des conditions de pâturage, s'associe al'evitement ou ala tolerance de la defoliation. On neglige souvent les traits clonaux dans l'etude des reponses fonctionnelles au pâturage, en depit de leur frequente presence dans la vegetation de prairie. Les auteurs ont cherche asavoir si les traits clonaux et la reponse ala defoliation sont impliques dans la resistance au pâturage. D'abord, ils ont estime la resistance au pâturage chez huit especes clonales en utilisant les patrons d'abondance dans une etude de terrain along terme. Ils ont ensuite analyse les correlations avec les traits sous des conditions non perturbees et les reponses ala defoliation dans une experience en jardin experimental. Quelques traits montrent une correlation avec la resistance au pâturage, bien qu'un seul soit un trait clonal (biomasse clonale souterraine). La resistance au pâturage montre une correlation negative avec la hauteur vegetative et la biomasse clonale souterraine et positive avec la biomasse des inflorescences, ce qui suggere que les especes rhizomateuses investissant peu dans la reproduction sexuee se trouvent desavantagees sous des conditions de pâturage. La hauteur vegetative ainsi que la biomasse clonale souterraine sont negativement affectees par la defoliation, mais ces effets negatifs sont moindres chez les especes exprimant le plus grande resistance au pâturage. Ces constatations montrent que l'utilisation de traits clonaux n'augmente que legerement les predictions au sujet de la resistance au pâturage, chez les huit especes etudiees. (Traduit par la Redaction)

International audience; Angiosperm microspores are grouped into tetrads before they mature into functional pollen grains. This tetrad stage is an important step in microsporogenesis. Tetrad shapes are diverse across angiosperms, with high levels of variation sometimes occurring within species, reflecting variation in early developmental events of nuclear and cell division (i.e., meiosis and cytokinesis). Among these developmental influences, the shape of the microsporocyte (pollen mother cell; hereafter PMC) is likely to influence tetrad shape. This article presents a test of this hypothesis in 19 species of higher Asparagales with a successive cytokinesis by inferring PMC shape from tetrads observed with epifluorescence microscopy. Sampled species show differences in PMC shape between groups of regular or irregular tetrads at the species level, and there is a strong component of PMC shape variation at the onset of meiosis on resulting tetrad shape, with more elongated PMCs yielding significantly more irregular tetrads.

Loss of varietal diversity is a worldwide challenge to crop species at risk for genetic erosion, while the loss of biological resources may hinder future breeding objectives. Loss of varieties has been mostly investigated in traditional agricultural systems where variety numbers are dramatically high, or for most economically important crop species for which comparison between pre-intensive and modern agriculture was possible. Varietal dynamics, i.e., turnover, or gains and losses of varieties by farmers, is nevertheless more rarely studied and while we currently have good estimates of genetic or varietal diversity for most crop species, we have less information as to how on farm agro-diversity changes and what cause its dynamics. We therefore investigated varietal dynamics in the agricultural yam system in the Caribbean island of Guadeloupe. We interviewed producers about varieties they cultivated in the past compared to their current varieties, in addition to characterizing yam cropping characteristics and both farm level and producers socio-economic features. We then used regression tree analyses to investigate the components of yam agro-diversity, varietal dynamics and impact of anthracnose on varieties. Our data demonstrated that no dramatic loss of varieties occurred within the last decades. Cultivation changes mostly affected widespread cultivars while frequency of uncommon varieties stayed relatively stable. Varietal dynamics nevertheless followed sub-regional patterns, and socio-economic influences such as producer age or farm crop diversity. Recurrent anthracnose epidemics since the 1970s did not alter varietal dynamics strongly, but sometimes translated into transition from Dioscorea alata to less susceptible species or into a decrease of yam cultivation. Factors affecting changes in agro-diversity were not relating to agronomy in our study, and surprisingly there were different processes delineating short term from long term varietal dynamics, independently of disease risk. Our results highlighted the importance of understanding varietal dynamics, an often overlooked component of agriculture sustainability, in addition to evolutionary forces shaping agro-diversity and genetic diversity distribution within crops. It is also crucial to understand how processes involved do scale up worldwide and for different crop species, so as not to mislead on-farm conservation efforts and efficacy of agro-diversity preservation.

Developmental constraints have been proposed to interfere with natural selection in limiting the available set of potential adaptations. Whereas this concept has long been debated on theoretical grounds, it has been investigated empirically only in a few studies. In this article, we evaluate the importance of developmental constraints during microsporogenesis (male meiosis in plants), with an emphasis on phylogenetic patterns in Asparagales. Different developmental constraints were tested by character reshuffling or by simulated distributions. Among the different characteristics of microsporogenesis, only cell wall formation appeared as constrained. We show that constraints may also result from biases in the correlated occurrence of developmental steps (e.g., lack of successive cytokinesis when wall formation is centripetal). We document such biases and their potential outcomes, notably the establishment of intermediate stages, which allow development to bypass such constraints. These insights are discussed with regard to potential selection on pollen morphology.

International audience; Plant pathogens have evolved many dispersal mechanisms, using biotic or abiotic vectors or a combination of the two. Rain splash dispersal is known from a variety of fungi, and can be an efficient driver of crop epidemics, with infectious strains propagating rapidly among often genetically homogenous neighboring plants. Splashing is nevertheless a local dispersal process and spores taking the droplet ride seldom move farther than a few decimeters. In this study, we assessed rain splash dispersal of conidia of the yam anthracnose agent, Colletotrichum gloeosporioides, in an experimental setting using a rain simulator, with emphasis on the impact of soil contamination (i.e., effect of re-splashing events). Spores dispersed up to 50 cm from yam leaf inoculum sources, though with an exponential decrease with increasing distance. While few spores were dispersed via re-splash from spore-contaminated soil, the proportion deposited via this mechanism increased with increasing distance from the initial source. We found no soil contamination carryover from previous rains, suggesting that contamination via re-splashing from contaminated soils mainly occurred within single rains. We conclude that most dispersal occurs from direct splashing, with a weaker contribution of indirect dispersal via re-splash.

International audience; The fungus Colletotrichum gloeosporioides is responsible for yam anthracnose, the main disease of Dioscorea alata crops. When epidemics occur, C. gloeosporioides is dispersed locally via rain splashing. Splashing is nevertheless a very local dispersal process and most spores are expected to land within a few decimeters after dispersal. In this study, we investigated dispersal by rain, estimating spore removal as a function of the number of impacting drops, modeling the dispersal gradient, differentiating primary splashing from re-splash (subsequent splashing from soil during rain events), and the effect of prior soil contamination on spore dispersal distance. We assessed rainsplash dispersal in two types of experimental settings, using either a single drop generator or a rain simulator, and disposed microscope slides as spore traps. Blue cotton staining was used to differentiate primary splashing from subsequent splashing (re-splash) and spores and drops were counted under light microscope. Results showed that a minimum of 3 impacting drops was needed to remove the first dispersed spores, while 20 incident drops were enough to remove 50% of the spore stock in a necrotic lesion. It was also found that inoculum source from leaves allowed for a dispersal up to 50 cm or more, though with an exponential decrease in distance traveled from source, while re-splash is weak but contributes more and more to dispersal with increasing distance from initial source. The results also demonstrated that prior soil contamination does not contribute to dispersal between rains.

International audience; Florivores are antagonists that damage flowers, and have direct negative effects on flowering and pollination of the attacked plants. While florivory has mainly been studied for its consequences on seed production or siring success, little is known about its impact on mating systems. Damage to flowers can alter pollinator attraction to the plant and may therefore modify patterns of pollen transfer. However, the consequences of damage for mating systems can take two forms: a decrease in flower number reduces opportunities for intra-inflorescence pollen deposition (geitonogamy), which, in turn, may lead to a decrease in selfing; whereas a decrease in floral display may also reduce overall visitation and thus increase the chances of self-pollination via facilitated or autonomous autogamy. We investigated the effects of damage by a bud-clipping weevil (Anthonomus signatus) in Fragaria virginiana in an experimental setting mimicking natural conditions. We found that increased damage led to an increase in selfing, a result consistent with the increased autogamy pathway. We discuss the implications of this finding and evaluate the generality of florivore-mediated mating system expression.

International audience; Predominantly outcrossing plant species are expected to accumulate recessive deleterious mutations, which call be purged when in a homozygous state following selfing. Individuals may vary in their genetic load because of different selfing histories, which could lead to differences in inbreeding depression among families. Lineage-dependent inbreeding depression can appear in gynodioecious species if obligatory outcrossed females are more likely to produce female offspring and if partially selfing hermaphrodites are more likely to produce hermaphrodites. We investigated inbreeding depression at the zygote, seed, and germination stages in the gynomonoecious-gynodioecious Dianthus sylvestris, including pure-sexed plants and a mixed morph. We performed hand-pollinations on 56 plants, belonging to the three morphs, each receiving 2-3 cross treatments (out-, sib- and self-pollination) on multiple flowers. Effects of cross treatments varied among stages and influenced seed provisioning, with sibling competition mainly occurring within outcrossed fruit,. We found significant inbreeding depression for seed mass and germination and cumulative early inbreeding depression varied greatly among families. Among sex morphs, we found that females and hermaphrodites differed in biparental inbreeding depression, whereas uniparental was similar for all. Significant inbreeding depression levels may play a role in female maintenance in this species, and individual variation in association with sex-lineages proclivity is discussed.

International audience; This paper presents the first broad overview of three main features of microsporogenesis (male meiosis) in angiosperms: cytokinesis (cell division), intersporal wall formation, and tetrad form. A phylogenetic comparative approach was used to test for correlated evolution among these characters and to make hypotheses about evolutionary trends in microsporogenesis. The link between features of microsporogenesis and pollen aperture type was examined. We show that the pathway associated with successive cytokinesis (cytoplasm is partitioned after each meiotic division) is restricted to wall formation mediated by centrifugally developing cell plates, and tetragonal (or decussate, T-shaped, linear) tetrads. Conversely, much more flexibility is observed when cytokinesis is simultaneous (two meiotic divisions completed before cytoplasmic partitioning). We suggest that the ancestral type of microsporogenesis for angiosperms, and perhaps for all seed plants, associated simultaneous cytokinesis with centripetal wall formation, resulting in a large diversity in tetrad forms, ranging from regular tetrahedral to tetragonal tetrads, including rhomboidal tetrads. From this ancestral pathway, switches toward successive cytokinesis occurred among basal angiosperms and monocots, generally associated with a switch toward centrifugal intersporal wall formation, whereas eudicots evolved toward an almost exclusive production of regular tetrahedral tetrads. No straightforward link is found between the type of microsporogenesis and pollen aperture type.

Gender-dimorphic plants are often subject to sex-differential enemy attack, but whether and how this contributes to trait evolution is unknown. To address this gap, we documented the spatiotemporal prevalence of sex-biased weevil damage in a gynodioecious strawberry. We then conducted path analysis to evaluate the direct and indirect pathways for weevils to affect female and male fertility and to mediate selection in two experimental gardens. Direct effects of weevils significantly reduced fertility and mediated selection on reproductive traits, even in the nonpreferred sex (females). Weevils significantly reduced floral display size in hermaphrodites in both gardens, and this translated into a substantial negative indirect effect on male fertility in the garden where the pathway to fertility via display was stronger. Thus, indirect effects of weevils can contribute to selection in hermaphrodites, which gain the majority of their fitness via male function. Our results also indicate that weevils often play a larger role than pollinators in shaping reproductive phenotype and thus raise the intriguing possibility that antagonists may be drivers of sexual dimorphism. Finally, our results support the view that mutualists, antagonists, and the abiotic environment should be considered when attempting to understand reproductive trait evolution in gender-dimorphic species.

Although the pollen grains produced in monocots are predominantly monosulcate (or monoporate), other aperture types are also found within this taxonomic group, such as the trichotomosulcate, inaperturate, zonaperturate, di-, or triaperturate types. The aperture pattern is determined during the young-tetrad stage of pollen development and it is known that some features of microsporogenesis can constrain the aperture type. For example, trichotomosulcate pollen is always associated with simultaneous cytokinesis, a condition considered as derived in the monocots. Our observations of the microsporogenesis pathway in a range of monocot species show that this pathway is surprisingly variable. Our results, however preliminary, reveal that variation in microsporogenesis concerns not only cytokinesis but also callose deposition among the microspores and shape of the tetrads. The role played by these features in aperture pattern determination is discussed.

The aperture pattern of pollen grains is a character defined as the number, shape, and position of apertures. Although this character is highly variable in angiosperms, two states are particularly widespread. Pollen grains with one polar aperture occur frequently in basal angiosperms and monocots while tricolpate pollen is a synapomorphy of the eudicots. Many morphological characters are the result of a compromise between selective forces (acting on morphology) and developmental constraints (limiting the range of possible morphologies). To investigate what are the respective roles of development and selection in the determination of aperture pattern in angiosperms, we have chosen to study the characteristics of cell division during male meiosis, since it has been shown that aperture pattern is determined during microsporogenesis. The present study focuses on Asparagales. From a selection of species belonging to the major families of Asparagales, we described the type of cytokinesis, the way callose is deposited, the shape of the tetrad, as well as the shape and position of apertures within the tetrad. We show that although pollen morphology is quite uniform in Asparagales (most species produce monosulcate pollen), the characteristics of cell division during male meiosis vary among families. A highly conserved developmental sequence is observed in higher Asparagales whereas lower Asparagales, and particularly Iridaceae, display different ways of achieving cell division.

• Background and Aims Early developmental events in microsporogenesis are known to play a role in pollen morphology: variation in cytokinesis type, cell wall formation, tetrad shape and aperture polarity are responsible for pollen aperture patterning. Despite the existence of other morphologies, monosulcate pollen is one of the most common aperture types in monocots, and is also considered as the ancestral condition in this group. It is known to occur from either a successive or a simultaneous cytokinesis. In the present study, the developmental sequence of microsporogenesis is investigated in several species of Asparagales that produce such monosulcate pollen, representing most families of this important monocot clade. • Methods The developmental pathway of microsporogenesis was investigated using light transmission and epifluorescence microscopy for all species studied. Confocal microscopy was used to confirm centripetal cell plate formation. • Key Results Microsporogenesis is diverse in Asparagales, and most variation is generally found between families. It is confirmed that the whole higher Asparagales clade has a very conserved microsporogenesis, with a successive cytokinesis and centrifugal cell plate formation. Centripetal cell wall formation is described in Tecophilaeaceae and Iridaceae, a feature that had so far only been reported for eudicots. • Conclusions Monosulcate pollen can be obtained from several developmental pathways, leading thus to homoplasy in the monosulcate character state. Monosulcate pollen should not therefore be considered as the ancestral state unless it is produced through the ancestral developmental pathway. The question about the ancestral developmental pathway leading to monosulcy remains open.