How to deal with neglected tropical diseases in the light of an African ethic

Many countries in Africa, and more generally those in the Global South with tropical areas, are plagued by illnesses that the wealthier parts of the world (mainly ‘the West’) neither suffer from nor put systematic effort into preventing, treating or curing. What does an ethic with a recognizably African pedigree entail for the ways various agents ought to respond to such neglected diseases? As many readers will know, a characteristically African ethic prescribes weighty duties to aid on the part of those in a position to do so, and it therefore entails that there should have been much more contribution from the Western, ‘developed’ world. However, what else does it prescribe, say, on the part of sub‐Saharan governments and the African Union, and are they in fact doing it? I particularly seek to answer these questions here, by using the 2013‐16 Ebola crisis in West Africa to illustrate what should have happened but what by and large did not.     

Pathogens of Ips amitinus: new species and comparison with Ips typographus

Ips amitinus and I. typographus are two serious pests of spruce in Europe, have similar bionomics and are likely to occur and meet on the same host trees. We therefore hypothesized that the two species support similar levels of similar pathogens. To test this hypothesis, we collected mature beetles from three trap trees at each of eight study sites and determined beetle numbers and pathogen infection levels. In total, 938 mature I. amitinus beetles and 3435 of I. typographus were dissected; five pathogens, as well as intestinal nematodes and endoparasitoids, were detected. The neogregarine Mattesia schwenkei is reported here for the first time as a new pathogen in 9.4% of I. amitinus individuals at one site. Average infection levels of most pathogens (Chytridiopsis typographi, Gregarina typographi, Mattesia schwenkei and parasitoids) were significantly higher in I. typographus than in I. amitinus. Metschnikowia typographi was confirmed only in Ips amitinus, while the microsporidium of Nosema typographi occurred only in I. typographus. Within‐season increases in G. typographi infection levels were documented in Ips amitinus.     

Nematodes associated with Ips cembrae (Coleoptera: Curculionidae): comparison of generations,sexes and sampling methods

A study of nematodes associated with the large larch bark beetle Ips cembrae (Heer 1836) was carried out at three locations in the Czech Republic. The proportion of beetles infested by endoparasitic nematodes (representatives of genera Contortylenchus, Parasitylenchus, Cryptaphelenchus and Parasitorhabditis) ranged from 29.9 to 50.9%. Significant differences were determined in nematode infestation levels among locations, generations and sampling methods. No differences were found in infestation rates between males and females. The percentage of bark beetles with phoretic nematodes ranged from 18 to 42.9%. Phoretic nematodes directly found under elytra, on wings and between body segments of the bark beetles belong to the genus Micoletzkya. However, adults and juveniles of other two phoretic species Laimaphelenchus penardi and Bursaphelenchus sp. were found in the gallery frass of I. cembrae. Infestation by phoretic nematodes positively correlated with the presence of mites under elytra.     

Expansion of the ISWI chromatin remodeler family with new active complexes

ISWI chromatin remodelers mobilize nucleosomes to control DNA accessibility. Complexes isolated to date pair one of six regulatory subunits with one of two highly similar ATPases. However, we find that each endogenously expressed ATPase co‐purifies with every regulatory subunit, substantially increasing the diversity of ISWI complexes, and we additionally identify BAZ2B as a novel, seventh regulatory subunit. Through reconstitution of catalytically active human ISWI complexes, we demonstrate that the new interactions described here are stable and direct. Finally, we profile the nucleosome remodeling functions of the now expanded family of ISWI chromatin remodelers. By revealing the combinatorial nature of ISWI complexes, we provide a basis for better understanding ISWI function in normal settings and disease.     

Balamuthia mandrillaris: In Vitro Interactions with Selected Protozoa and Algae

Although Balamuthia mandrillaris was identified more than two decades ago as an agent of fatal granulomatous encephalitis in humans and other animals, little is known about its ecological niche, biological behavior in the environment, food preferences and predators, if any. When infecting humans or other animals, Balamuthia feeds on tissues; and in vitro culture, it feeds on mammalian cells (monkey kidney cells, human lung fibroblasts, and human microvascular endothelial cells). According to recent reports, it is believed that Balamuthia feeds on small amebae, for example, Acanthamoeba that are present in its ecological niche. To test this hypothesis, we associated Balamuthia on a one‐on‐one basis with selected protozoa and algae. We videotaped the behavior of Balamuthia in the presence of a potential prey, its ability to hunt and attack its food, and the time required to eat and cause damage to the target cell by direct contact. We found that B. mandrillaris ingested trophozoites of Naegleria fowleri, Naegleria gruberi, Acanthamoeba spp., Trypanosoma cruzi epimastigotes, Toxoplasma gondii tachyzoites, and Giardia. However, it did not feed on Acanthamoeba cysts or algae. Balamuthia caused cytolysis of T. cruzi epimastigotes and T. gondii tachyzoites by direct contact. Balamuthia trophozoites and cysts were, however, eaten by Paramecium sp.     

Phylogenetics of tribe Sabiceeae (Ixoroideae,Rubiaceae) revisited,with a new subgeneric classification for Sabicea

Tribe Sabiceeae (Ixoroideae, Rubiaceae) has undergone recent taxonomical changes with the incorporation of the related genera Ecpoma, Pseudosabicea and Stipularia into the type genus Sabicea. We use phylogenetic analysis and morphological data to verify the relationships among members of the tribe, including the most comprehensive taxon sampling of the tribe to date with 74 of 145 species. Sequence data from the nuclear internal transcribed spacer (ITS) and three plastid markers (petD, rps16, trnT–F) were used to infer relationships among the members of the tribe. Individual analyses using maximum likelihood, parsimony and Bayesian approaches reveal several supported clades: the former genus Stipularia is resolved as a monophyletic unit, but Ecpoma is monophyletic only if Sabicea urbaniana and Sabicea xanthotricha are included (corresponding to Sabicea subgenus Stipulariopsis sensu Wernham). Pseudosabicea is biphyletic, with one clade corresponding to section Anisophyllae of Hallé (1964) and the other one to the other sections (Floribundae and Sphaericae) of the genus. Eleven morphological characteristics were recorded for all species studied and seven have been mapped onto the phylogenetic tree to study their evolution in the group and assess their value for the classification of Sabicea s.l. Finally, our study shows that a combination of diagnostic characteristics should be used to differentiate each group and we propose to recognise four subgenera in Sabicea.     

Invasive legumes can associate with many mutualists of native legumes,but usually do not

Mutualistic interactions can strongly influence species invasions, as the inability to form successful mutualisms in an exotic range could hamper a host's invasion success. This barrier to invasion may be overcome if an invader either forms novel mutualistic associations or finds and associates with familiar mutualists in the exotic range. Here, we ask (1) does the community of rhizobial mutualists associated with invasive legumes in their exotic range overlap with that of local native legumes and (2) can any differences be explained by fundamental incompatibilities with particular rhizobial genotypes? To address these questions, we first characterized the rhizobial communities naturally associating with three invasive and six native legumes growing in the San Francisco Bay Area. We then conducted a greenhouse experiment to test whether the invasive legume could nodulate with any of a broad array of rhizobia found in their exotic range. There was little overlap between the Bradyrhizobium communities associated with wild‐grown invasive and native legumes, yet the invasive legumes could nodulate with a broad range of rhizobial strains under greenhouse conditions. These observations suggest that under field conditions in their exotic range, these invasive legumes are not currently associating with the mutualists of local native legumes, despite their potential to form such associations. However, the promiscuity with which these invading legumes can form mutualistic associations could be an important factor early in the invasion process if mutualist scarcity limits range expansion. Overall, the observation that invasive legumes have a community of rhizobia distinct from that of native legumes, despite their ability to associate with many rhizobial strains, challenges existing assumptions about how invading species obtain their mutualists. These results can therefore inform current and future efforts to prevent and remove invasive species.     

Applicability of AFLP Fingerprinting Markers to Molecular Discrimination of the Three Main Fungal Species Associated with Grapevine Decline in Spain

Diplodia seriata, Phaeomoniella chlamydospora and Phaeoacremonium aleophilum are the three main species associated with grapevine decline in Spain. AFLP markers were developed to discriminate Spanish populations of these species. The markers were used to genotype isolates of D. seriata, P. chlamydospora and P. aleophilum. AFLP markers were valuable in performing population genetic studies as genetic variability (K_x) ranged from 0.07 in the P. chlamydospora population to 0.28 in the D. seriata population. Species‐specific markers obtained using only two AFLP combinations clearly discriminate D. seriata, P. chlamydospora and P. aleophilum and are a useful tool in simultaneous identification tests.     

Identification of Fungal Species Associated with Cladode Spot of Prickly Pear and Their Sensitivity to Chitosan

México is the most important producer of prickly pear (Opuntia ficus‐indica) in the world. There are several fungal diseases that can have a negative impact on their yields. In this study, there was a widespread fungal richness on cladodes spot of prickly pears from México. A total of 41 fungi isolates were obtained from cladodes spot; 11 of them were morphologically different. According to the pathogenicity test, seven isolates caused lesions on cladodes. The morphological and molecular identification evidenced the isolation of Colletotrichum gloeosporioides, Alternaria alternata, Fusarium lunatum, Curvularia lunata. All these species caused similar symptoms of circular cladodes spot. However, it is noticeable that some lesions showed perforation and detachment of affected tissues by Fusarium lunatum. To our knowledge, this is the first report of the Fusarium lunatum as phytopathogenic fungus of cladodes of prickly pear. The chitosan inhibited the mycelium growth in the seven isolates of phytopathogenic fungi. Chitosan applications diminished the disease incidence caused by C. gloeosporioies and F. lunatum in 40 and 100%, respectively. Likewise, the lesion severity index in cladodes decreased. There are no previous reports about the application of chitosan on cladodes of prickly pears for the control of phytopathogenic fungi. Therefore, this research could contribute to improve the strategies for the management of diseases in prickly pear.     

Validation of genetic polymorphisms on BTA14 associated with carcass trait in a commercial Hanwoo population

The objective of this study was to validate the association of significant SNPs identified from a previous genome‐wide association study with carcass weight (CWT) in a commercial Hanwoo population. We genotyped 13 SNPs located on BTA14 in 867 steers from Korea Hanwoo feedlot bulls. Of these 13 SNPs, five SNPs, namely rs29021868, rs110061498, rs109546980, rs42404006 and rs42303720, were found to be significantly associated (P < 0.001) with CWT. These five significant markers spanned the 24.3 to 29.4 Mb region of BTA14. The most significant marker (rs29021868) for CWT in this study had a 13.07 kg allele substitution effect and accounted for 2.4% of the additive genetic variance in the commercial Hanwoo population. The SNP marker rs109546980 was found to be significantly associated with both CWT (P < 0.001) and eye muscle area (P < 0.001) and could potentially be exploited for marker‐assisted selection in Hanwoo cattle. We also genotyped the ss319607402 variation, which maps to intron2 of PLAG1 gene and which is already reported to be associated with height, to identify any significant association with carcass weight; however, no such association was observed in this Hanwoo commercial population.     

Fusarium Species Associated with Mango Malformation in Peninsular Malaysia

Mango malformation has become the most important global disease on mango. Fusarium species previously associated with this disease include F. mangiferae, F. mexicanum, F. sterilihyphosum, F. proliferatum, F. subglutinans and F. tupiense. A few strains of F. proliferatum have been reported from Malaysia, but in this study, we report the results of more extensive sampling. The recovered strains were evaluated with morphology, mating tester strain cross‐fertility, amplified fragment length polymorphisms (AFLPs), and partial DNA sequences of the genes encoding translation elongation factor 1‐α (tef‐1α) and β‐tubulin (tub‐2). Amongst the 43 strains evaluated, three species were identified – F. proliferatum, F. mangiferae and F. subglutinans – with F. proliferatum being the most frequent (69%). None of the Fusarium species that appear to originate in the Americas were recovered in Malaysia, which suggests special measures may be warranted to keep these species from entering the country.     

Effects of the Epichloë fungal endophyte symbiosis with Schedonorus pratensis on host grass invasiveness

Initial studies of grass–endophyte mutualisms using Schedonorus arundinaceus cultivar Kentucky‐31 infected with the vertically transmitted endophyte Epichloë coenophiala found strong, positive endophyte effects on host‐grass invasion success. However, more recent work using different cultivars of S. arundinaceus has cast doubt on the ubiquity of this effect, at least as it pertains to S. arundinaceus–E. coenophiala. We investigated the generality of previous work on vertically transmitted Epichloë‐associated grass invasiveness by studying a pair of very closely related species: S. pratensis and E. uncinata. Seven cultivars of S. pratensis and two cultivars of S. arundinaceus that were developed with high‐ or low‐endophyte infection rate were broadcast seeded into 2 × 2‐m plots in a tilled, old‐field grassland community in a completely randomized block design. Schedonorus abundance, endophyte infection rate, and co‐occurring vegetation were sampled 3, 4, 5, and 6 years after establishment, and the aboveground invertebrate community was sampled in S. pratensis plots 3 and 4 years after establishment. Endophyte infection did not enable the host grass to achieve high abundance in the plant community. Contrary to expectations, high‐endophyte S. pratensis increased plant richness relative to low‐endophyte cultivars. However, as expected, high‐endophyte S. pratensis marginally decreased invertebrate taxon richness. Endophyte effects on vegetation and invertebrate community composition were inconsistent among cultivars and were weaker than temporal effects. The effect of the grass–Epichloë symbiosis on diversity is not generalizable, but rather specific to species, cultivar, infection, and potentially site. Examining grass–endophyte systems using multiple cultivars and species replicated among sites will be important to determine the range of conditions in which endophyte associations benefit host grass performance and have subsequent effects on co‐occurring biotic communities.     

A preliminary assessment of the response of a native reptile assemblage to spot‐spraying invasive Bitou Bush with glyphosate herbicide

During recent work examining the effects of Bitou Bush (Chrysanthemoides monilifera ssp. rotundata) invasion on native reptile assemblages in coastal heathland vegetation in Eastern Australia, unplanned spot‐spraying of glyphosate occurred at some of our experimental sites invaded by Bitou Bush. We used this unexpected herbicide application as an opportunity to provide a preliminary assessment of the short‐term impacts on reptiles of glyphosate spot‐spraying of Bitou Bush. Using an M‐BARCI design, we compared reptile assemblages among uninvaded (reference) sites, invaded (control) sites and invaded and sprayed (impact) sites before and after spraying. We found no significant short‐term (7 – 10 months) differences in reptile abundance, species richness or assemblage composition among invaded, uninvaded and sprayed sites before and after glyphosate application. We cautiously interpret our results to generate a preliminary finding that spot‐spraying of Bitou Bush with glyphosate appears not to have a deleterious effect on reptile assemblages at seven and ten months following herbicide application. While we would not recommend basing management decisions on the outcomes of our study alone, we suggest that our findings can be used to assist in the development of strategic analyses of glyphosate impacts on native flora and fauna.     

Environmental constraints on oviposition of aquatic invertebrates with contrasting life cycles in two human‐modified streams

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