Comparing genetic diversity, genetic differentiation, and performance between native and nonnative populations has advanced our knowledge of contemporary evolution and its ecological consequences. However, such between‐range comparisons can be complicated by high among‐population variation within native and nonnative ranges. For example, native vs. nonnative comparisons between small and non‐representative subsets of populations for species with very large distributions have the potential to mislead because they may not sufficiently account for within‐range adaptation to climatic conditions, and demographic history that may lead to non‐adaptive evolution. We used the cosmopolitan weed Conyza canadensis to study the interplay of adaptive and demographic processes across, to our knowledge, the broadest climatic gradient yet investigated in this context. To examine the distribution of genetic diversity, we genotyped 26 native and 26 nonnative populations at 12 microsatellite loci. Furthermore, we recorded performance traits for 12 native and 13 nonnative populations in the field and in the common garden. To analyze how performance was related to range and/or climate, we fit pedigree mixed‐effects models. These models weighed the population random effect for co‐ancestry to account for the influence of demographic history on phenotypic among‐population differentiation. Genetic diversity was very low, selfing rates were very high, and both were comparable between native and nonnative ranges. Nonnative populations out‐performed native populations in the field. However, our most salient result was that both neutral genetic differentiation and common garden performance were far more correlated with the climatic conditions from which populations originated than native vs. nonnative range affiliation. Including co‐ancestry of our populations in our models greatly increased explained variance and our ability to detect significant main effects for among‐population variation in performance. High propagule pressure and high selfing rates, in concert with the ability to adapt rapidly to climatic gradients, may have facilitated the global success of this weed. Neither native nor nonnative populations were homogeneous groups but responded comparably to similar environments in each range. We suggest that studies of contemporary evolution should consider widely distributed and genotyped populations to disentangle native vs. nonnative range effects from varying adaptive processes within ranges and from potentially confounding effects of demographic history.

Eight new and 10 known compounds, were isolated from an organic extract of the bulbs of Bellevalia eigii as part of a search for anticancer leads from native plants of Jordan. Of these, the series of 16 homoisoflavonoids (1-16), comprise the seven new analogues 7-O-methyl-3′-hydroxy-3,9-dihydropunctatin (3), 6-hydroxy-7-O-methyl-3,9-dihydropunctatin (6), 7,4′-di-O-methyl-3′-hydroxy-3,9-dihydropunctatin (9), 7-O-methylpunctatin (10), 7-O-methyl-3′-hydroxypunctatin (13), 5-hydroxy-7,8-dimethoxychroman-4-one (14), and 7-O-methyl-8-demethoxy-3-hydroxy-3,9-dihydropunctatin (15), as well as the known ferulic acid-derived acrylamide (17), and the new methylthioacrylate bellegimycin (18). The structures were elucidated using a set of spectroscopic and spectrometric techniques; the absolute configurations of compounds 1–9, 15, and 16 were determined using ECD spectroscopy, while a modified Mosher’s ester method was used for compound 18. Optical rotation data for the known compounds 1, 2, and 8 are reported here for the first time. The cytotoxic activities of all compounds were evaluated using the MDA-MB-435 (melanoma) and HT-29 (colon) cancer cell lines. Compounds 4 and 9 were the most potent on the latter cell line with IC50 values of 1.0 and 1.1 μM, respectively. Compounds 1-18 were assessed for antimicrobial activity using a collection of bacteria and fungi; compounds 4 and 12 showed promising activity against the bacterium Mycobacterium smegmatis with MIC values of 17 and 24 μg/mL, respectively.

Question: What is the impact of grazing and/or afforestation on grassland diversity, species composition and cover parameters? Location: Semi-arid Mediterranean grasslands of Jordan. Methods: Vegetation, litter, bare soil and rock cover were compared among four management types -free grazing and protected from grazing with three levels of tree cover. Species composition, plant cover, species richness and evenness were used to evaluate differences in vegetation among management types. Species composition differences among management types were also investigated. Results: Semi-arid Mediterranean grasslands harbour appreciable levels of plant biodiversity. Grazing did not affect plant diversity, indicating the high resilience against and adaptation to grazing; however, grazing affected species composition and cover parameters. Afforestation seems to protect soil through higher litter cover but its impact on plant biodiversity was negative and markedly affected species composition. Conclusions: Neither protection from grazing or massive afforestation alone are sufficient for conserving biodiversity in this system. A management model is suggested where the landscape should be maintained as a mosaic of four management types: complete protection from grazing, grazing rotation, planting sparse trees in eroded areas and revegetating degraded areas using native, herbaceous and grazing tolerant species.Abbreviations: ANPP = Above-ground net primary productivity; FG = Free grazing; PD = Protected -dense cover; PN = Protected -no tree cover; PS = Protected -sparse cover.

Soil biota can determine plant invasiveness, yet biogeographical comparisons of microbial community composition and function across ranges are rare. We compared interactions between Conyza canadensis, a global plant invader, and arbuscular mycorrhizal (AM) fungi in 17 plant populations in each native and non-native range spanning similar climate and soil fertility gradients. We then grew seedlings in the greenhouse inoculated with AM fungi from the native range. In the field, Conyza plants were larger, more fecund, and associated with a richer community of more closely related AM fungal taxa in the non-native range. Fungal taxa that were more abundant in the non-native range also correlated positively with plant biomass, whereas taxa that were more abundant in the native range appeared parasitic. These patterns persisted when populations from both ranges were grown together in a greenhouse; non-native populations cultured a richer and more diverse AM fungal community and selected AM fungi that appeared to be more mutualistic. Our results provide experimental support for evolution toward enhanced mutualism in non-native ranges. Such novel relationships and the rapid evolution of mutualisms may contribute to the disproportionate abundance and impact of some non-native plant species.

Salvia spinosa L. and Salvia syriaca L. are perennial medicinal herbs that occur in the Mediterranean, Irano‐Turanian and Saharo‐Arabian phytogeographic regions of Jordan. With respect to the seed germination requirements, prevailing environmental conditions in each phytogeographic region may promote local adaptation and consequently affect the distribution range of the species. Using seeds of both species collected from populations across the three regions, we tested responses to variations in temperature and salinity under laboratory conditions. Both species showed significant differences in cumulative germination percentages and germination rates (modified Timson Index) with temperature, while origin only significantly affected S. spinosa seeds. Both species germinated best under the highest temperature regime (32/20°C). The low temperature regime (8/4°C) completely inhibited germination in S. syriaca, wheras it led to 80% to 95% germination in S. spinosa, with significant variation being recorded between the phytogeographic regions. For both species, salt solutions of 0, 25 and 50 mM NaCl yielded the highest germination percentages and rates, which sharply and significantly declined at higher concentrations (100 and 200 mM NaCl). Our results provide evidence of local adaptation of the study species to salinity and temperature in the respective maternal environments, particularly in the Irano‐Turanian and Saharo‐Arabian regions. Such differentiation should be accounted for in future conservation planning.