Science Rendue Possible
Silva, C. P., D. N. López, P. I. Naulin, and S. A. Estay. 2023. Can suitability indices predict plant growth in the invaded range? The case of Acacias species. Frontiers in Plant Science 14. https://doi.org/10.3389/fpls.2023.1125019
IntroductionForestry in many parts of the world depends on exotic species, making this industry a source of invasions in some countries. Among others, plantations of the genus Pinus, Eucalyptus, Acacia, Populus, and Pseudotsuga underpin the forestry industry and are a vital component of many countries economies. Among woody plants, the cosmopolitan genus Acacia includes some of the most commonly planted trees worldwide. In order to prevent, manage and control invasive plant species, one of the most used tools is species distribution models. The output of these models can also be used to obtain information about population characteristics, such as spatial abundance patterns or species performance. Although ecological theory suggests a direct link between fitness and suitability, this link is often absent. The reasons behind the lack of this relationship are multiple. Chile is one of the countries where Acacia species, in particular, A. dealbata and A. melanoxylon, have become invaders. MethodsHere, we used climatic and edaphic variables to predict thepotentially suitable habitats for A. dealbata and A. melanoxylon in continental Chile and evaluate if the suitability indices obtained from these models are associated with the observed performance of the trees along the country. ResultsOur models show that variable importance showed significant similarities between the variables that characterize each species’ niche. However, despite the high accuracy of our models, we did not observe an association between suitability and tree growth.DiscussionThis disconnection between suitability and performance can result from multiple causes, from structural limitations, like the lack of biotic interactions in the models, to methodological issues, like the usefulness of the performance metric used. Whatever the scenario, our results suggest that plans to control invasive species should be cautious in assuming this relationship in their design and consider other indicators such as species establishment success.
Vieira Araújo, F. H., J. C. B. dos Santos, J. B. dos Santos, A. Ferreira da Silva, R. S. Ramos, R. Siqueira da Silva, and F. Shabani. 2023. Spread of Striga asiatica through suitable climatic conditions: Risk assessment in new areas producing Zea mays in South America. Journal of Arid Environments 210: 104924. https://doi.org/10.1016/j.jaridenv.2022.104924
Striga asiatica (dicot), an obligate hemiparasitic of monocots, is a potential threat to South America. Determining the ecological factors that explain the occurrence and predicting suitable areas for S. asiatica are fundamental for designing prevention strategies. We developed a Spatio-temporal dynamics model and evaluated Brazil's Weekly Growth Index (GIW) for S. asiatica. We analyzed four Brazilian regions (Central-West, South, Southeast, and Northeast) to verify the local seasonal variation of the species in climatic data. Our results indicated areas with favorable climatic suitability for the species in part of South America. Seasonal assessment models showed that high rainfall and the dry and cold periods common in tropical regions affect the GIW for S. asiatica. When we associate periods with maximum rainfall of 53 mm per week and temperature above 20 °C, the GIW approaches the optimal index for the regions evaluated, indicating the influence of soil moisture and air temperature. Our risk assessment indicated that the Southeast and Northeast are at the most significant risk of S. asiatica invasion. Projections for climate change between 2040–2059 showed expansions in areas suitable for S. asiatica compared to the current climate of South America.
Vieira Araújo, F. H., A. Ferreira da Silva, R. S. Ramos, S. R. Ferreira, J. Barbosa dos Santos, R. Siqueira da Silva, and F. Shabani. 2022. Modelling climate suitability for Striga asiatica, a potential invasive weed of cereal crops. Crop Protection 160: 106050. https://doi.org/10.1016/j.cropro.2022.106050
Striga asiatica (Lamiales: Orobanchaceae), a hemi-parasitic plant native to sub-Saharan Africa and tropical Asia, is particularly problematic to rice, corn, and sorghum cultivation in Africa. Striga asiatica produces a large number of small sized (<0.5 mm) seeds, thereby facilitating easy dispersion by commercial exchange of contaminated grains. The distribution of this species in Africa is regulated by climate, which is the main factor determining local suitability. Modelling is a useful tool to analyse climate suitability for species. This study aimed to determine the areas more vulnerable to S. asiatica invasion both in the present and under the projected climate change model using two methods: MaxEnt (as a correlative approach) and CLIMEX (as a semi-mechanistic approach). The MIROC-H Global Climate Model and the A2 and RCP 8.5 scenarios (the most pessimistic one) were used. Our projections indicated areas suitable for S. asiatica invasion in all continents under both present and projected climate change, with high suitability areas in South America, Africa, and Europe. We found agreement and disagreement between CLIMEX and MaxEnt outputs and the extent of disagreement on the increases in climate suitability by 2050 and 2100 in North America, Europe, and eastern, southern, and western Australia. This study provides a useful tool to design strategies aimed at preventing the introduction and establishment of S. asiatica in South America, with considerable agreement between CLIMEX and MaxEnt outputs.
Ramirez-Villegas, J., C. K. Khoury, H. A. Achicanoy, M. V. Diaz, A. C. Mendez, C. C. Sosa, Z. Kehel, et al. 2022. State of ex situ conservation of landrace groups of 25 major crops. Nature Plants 8: 491–499. https://doi.org/10.1038/s41477-022-01144-8
Crop landraces have unique local agroecological and societal functions and offer important genetic resources for plant breeding. Recognition of the value of landrace diversity and concern about its erosion on farms have led to sustained efforts to establish ex situ collections worldwide. The degree to which these efforts have succeeded in conserving landraces has not been comprehensively assessed. Here we modelled the potential distributions of eco-geographically distinguishable groups of landraces of 25 cereal, pulse and starchy root/tuber/fruit crops within their geographic regions of diversity. We then analysed the extent to which these landrace groups are represented in genebank collections, using geographic and ecological coverage metrics as a proxy for genetic diversity. We find that ex situ conservation of landrace groups is currently moderately comprehensive on average, with substantial variation among crops; a mean of 63% ± 12.6% of distributions is currently represented in genebanks. Breadfruit, bananas and plantains, lentils, common beans, chickpeas, barley and bread wheat landrace groups are among the most fully represented, whereas the largest conservation gaps persist for pearl millet, yams, finger millet, groundnut, potatoes and peas. Geographic regions prioritized for further collection of landrace groups for ex situ conservation include South Asia, the Mediterranean and West Asia, Mesoamerica, sub-Saharan Africa, the Andean mountains of South America and Central to East Asia. With further progress to fill these gaps, a high degree of representation of landrace group diversity in genebanks is feasible globally, thus fulfilling international targets for their ex situ conservation. By analysing the state of representation of traditional varieties of 25 major crops in ex situ repositories, this study demonstrates conservation progress made over more than a half-century and identifies the gaps remaining to be filled.
Colli-Silva, M., J. R. Pirani, and A. Zizka. 2022. Ecological niche models and point distribution data reveal a differential coverage of the cacao relatives (Malvaceae) in South American protected areas. Ecological Informatics 69: 101668. https://doi.org/10.1016/j.ecoinf.2022.101668
For many regions, such as in South America, it is unclear how well the existent protected areas network (PAs) covers different taxonomic groups and if there is a coverage bias of PAs towards certain biomes or species. Publicly available occurrence data along with ecological niche models might help to overcome this gap and to quantify the coverage of taxa by PAs ensuring an unbiased distribution of conservation effort. Here, we use an occurrence database of 271 species from the cacao family (Malvaceae) to address how South American PAs cover species with different distribution, abundance, and threat status. Furthermore, we compared the performance of online databases, expert knowledge, and modelled species distributions in estimating species coverage in PAs. We found 79 species from our survey (29% of the total) lack any record inside South American PAs and that 20 out of 23 species potentially threatened with extinction are not covered by PAs. The area covered by South American PAs was low across biomes, except for Amazonia, which had a relative high PA coverage, but little information on species distribution within PA available. Also, raw geo-referenced occurrence data were underestimating the number of species in PAs, and projections from ecological niche models were more prone to overestimating the number of species represented within PAs. We discuss that the protection of South American flora in heterogeneous environments demand for specific strategies tailored to particular biomes, including making new collections inside PAs in less collected areas, and the delimitation of more areas for protection in more known areas. Also, by presenting biasing scenarios of collection effort in a representative plant group, our results can benefit policy makers in conserving different spots of tropical environments highly biodiverse.
Sarker, U., Y.-P. Lin, S. Oba, Y. Yoshioka, and K. Hoshikawa. 2022. Prospects and potentials of underutilized leafy Amaranths as vegetable use for health-promotion. Plant Physiology and Biochemistry 182: 104–123. https://doi.org/10.1016/j.plaphy.2022.04.011
Climate change causes environmental variation worldwide, which is one of the most serious threats to global food security. In addition, more than 2 billion people in the world are reported to suffer from serious malnutrition, referred to as ‘hidden hunger.’ Dependence on only a few crops could lead to the loss of genetic diversity and high fragility of crop breeding in systems adapting to global scale climate change. The exploitation of underutilized species and genetic resources, referred to as orphan crops, could be a useful approach for resolving the issue of adaptability to environmental alteration, biodiversity preservation, and improvement of nutrient quality and quantity to ensure food security. Moreover, the use of these alternative crops will help to increase the human health benefits and the income of farmers in developing countries. In this review, we highlight the potential of orphan crops, especially amaranths, for use as vegetables and health-promoting nutritional components. This review highlights promising diversified sources of amaranth germplasms, their tolerance to abiotic stresses, and their nutritional, phytochemical, and antioxidant values for vegetable purposes. Betalains (betacyanins and betaxanthins), unique antioxidant components in amaranth vegetables, are also highlighted regarding their chemodiversity across amaranth germplasms and their stability and degradation. In addition, we discuss the physiological functions, antioxidant, antilipidemic, anticancer, and antimicrobial activities, as well as the biosynthesis pathway, molecular, biochemical, genetics, and genomic mechanisms of betalains in detail.
Xue, T., S. R. Gadagkar, T. P. Albright, X. Yang, J. Li, C. Xia, J. Wu, and S. Yu. 2021. Prioritizing conservation of biodiversity in an alpine region: Distribution pattern and conservation status of seed plants in the Qinghai-Tibetan Plateau. Global Ecology and Conservation 32: e01885. https://doi.org/10.1016/j.gecco.2021.e01885
The Qinghai-Tibetan Plateau (QTP) harbors abundant and diverse plant life owing to its high habitat heterogeneity. However, the distribution pattern of biodiversity hotspots and their conservation status remain unclear. Based on 148,283 high-resolution occurrence coordinates of 13,450 seed plants, w…
Iannella, M., P. D’Alessandro, W. De Simone, and M. Biondi. 2021. Habitat Specificity, Host Plants and Areas of Endemism for the Genera-Group Blepharida s.l. in the Afrotropical Region (Coleoptera, Chrysomelidae, Galerucinae, Alticini). Insects 12: 299. https://doi.org/10.3390/insects12040299
The genus Calotheca Heyden (Chrysomelidae) is mainly distributed in the eastern and southern parts of sub-Saharan Africa, with some extensions northward, while Blepharidina Bechyné occurs in the intertropical zone of Africa, with two subgenera, Blepharidina s. str. and Blepharidina(Afroblepharida) B…
Iqbal, I., A. Shabbir, K. Shabbir, M. Barkworth, F. Bareen, and S. Khan. 2020. Evolvulus nummularius (L.) L. (Convolvulaceae): a new alien plant record for Pakistan. BioInvasions Records 9: 702–711. https://doi.org/10.3391/bir.2020.9.4.04
Evolvulus nummularius (L.) L., a member of the Convolvulaceae, is native to Mexico and South America but nowadays grows around the world in many tropical and subtropical regions. Its presence in Pakistan, where it has become naturalized, is reported here for the first time. It was first discovered i…
Rozefelds, A. C., G. Stull, P. Hayes, and D. R. Greenwood. 2020. The fossil record of Icacinaceae in Australia supports long-standing Palaeo-Antarctic rainforest connections in southern high latitudes. Historical Biology 33: 2854–2864. https://doi.org/10.1080/08912963.2020.1832089
Fossil fruits of Icacinaceae are recorded from two Cenozoic sites in Australia, at Launceston in northern Tasmania and the Poole Creek palaeochannel in northern South Australia, representing the first report of fossil Icacinaceae from Australia. The Launceston material includes two endocarps with br…