Fusarium is a genus of filamentous fungi that contains many agronomically important plant pathogens, mycotoxin producers, and opportunistic human pathogens. Comparative analyses have revealed that the Fusarium genome is compartmentalized into regions responsible for primary metabolism and reproduction (core genome), and pathogen virulence, host specialization, and possibly other functions (adaptive genome). Genes involved in virulence and host specialization are located on pathogenicity chromosomes within strains pathogenic to tomato (Fusarium oxysporum f. sp. lycopersici) and pea (Fusarium 'solani' f. sp. pisi). The experimental transfer of pathogenicity chromosomes from F. oxysporum f. sp. lycopersici into a nonpathogen transformed the latter into a tomato pathogen. Thus, horizontal transfer may explain the polyphyletic origins of host specificity within the genus. Additional genome-scale comparative and functional studies are needed to elucidate the evolution and diversity of pathogenicity mechanisms, which may help inform novel disease management strategies against fusarial pathogens.

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Iturins and closely related lipopeptides constitute a family of antifungal compounds known as iturinic lipopeptides that are produced by species in the Bacillus subtilis group. The compounds that comprise the family are: iturin, bacillomycin D, bacillomycin F, bacillomycin L, mycosubtilin, and mojavensin. These lipopeptides are prominent in many Bacillus strains that have been commercialized as biological control agents against fungal plant pathogens and as plant growth promoters. The compounds are cyclic heptapeptides with a variable length alkyl sidechain, which confers surface activity properties resulting in an affinity for fungal membranes. Above a certain concentration, enough molecules enter the fungal cell membrane to create a pore in the cell wall, which leads to loss of cell contents and cell death. This study identified 330 iturinic lipopeptide clusters in publicly available genomes from the B. subtilis species group. The clusters were subsequently assigned into distinguishable types on the basis of their unique amino acid sequences and then verified by HPLC MS/MS analysis. The results show some lipopeptides are only produced by one species, whereas certain others can produce up to three. In addition, four species previously not known to produce iturinic lipopeptides were identified. The distribution of these compounds among the B. subtilis group species suggests that they play an important role in their speciation and evolution.

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Reproduction is timed so that parturition coincides with optimal conditions for offspring survival, with strong fitness implications in northern regions. However, in the southern United States the breeding season of white-tailed deer (Odocoileus virginianus) is relatively heterogeneous over short distances. To test the hypothesis that genetic differences account for heterogeneity in breeding dates, we compared the degree of mitochondrial (mtDNA) and microsatellite DNA differentiation among 6 pairs of adjacent populations with breeding dates differing by an average of 35 days (DBD group) and 4 pairs of populations displaying similar breeding dates (SBD group) differing by no more than 2 days. Average mtDNA differentiation between pairs in the DBD group (F ST ¼ 0.408, SD ¼ 0.190) was larger (P ¼ 0.03) than for the SBD group (F ST ¼ 0.140, SD ¼ 0.092). The average differentiation at biparentally inherited microsatellite loci within the SBD group (F ST ¼ 0.028, SD ¼ 0.021) did not differ from that observed for the DBD group (F ST ¼ 0.047, SD ¼ 0.024; P ¼ 0.200). The similarity at biparentally inherited loci suggests that there are no cryptic barriers and populations are connected by male dispersal. The greater differences in mtDNA lineages between geographically proximate populations in the DBD group imply a maternal genetic effect on the timing of breeding, likely maintained by female philopatry. We hypothesize that this difference is a genetic legacy of restocking efforts and the recovery of remnant localized populations. Translocation efforts require careful consideration of differences between source and recipient populations. Breeding dates that differ among some proximate southern deer populations may be a fixed trait that must be considered when establishing management objectives and harvest criteria. Ó 2015 The Wildlife Society.

BACKGROUND: Some plant essential oils have insecticidal properties against mosquitoes and can be harnessed as ecofriendly tools for mosquito control. We conducted bioassays to determine the toxicity of Italian honeysuckle (Lonicera caprifolium) essential oil and its fractions against larvae of the yellow fever mosquito, Aedes aegypti. RESULTS: Sixteen constituents were identified in honeysuckle essential oil compared to 15, 15, 15, and 11 constituents in fractions A, B, C, and E, respectively. The chemical constituents for fraction D were not determined due to lack of enough fraction sample. The two major constituents identified were patchouli alcohol (29.3%) and 6-acetyl-1,1,2,4,4,7-hexamethyltetralin (20.6%) in whole essential oil, alpha-bulnesene (27.6%) and 6-acetyl-1,1,2,4,4,7-hexamethyltetralin (23.2%) in fraction A, unknown chemical (47.3%) and diethyl phthalate (19.5%) in fraction B, unknown chemical (38.3%) and diethyl phthalate (23.2%) in fraction C, and patchouli alcohol (58.7%) and diethyl phthalate (20.5%) in fraction E. The LC 50 for whole essential oil was 34. 4 ppm and significantly higher than 20.6, 19.7, 18.6, and 17.7 ppm for fractions B, C, D, and E, respectively. In contrast, fraction A was inactive. At 50 ppm, all individual constituents tested were less toxic than the whole essential oil with exception of patchouli alcohol, which caused 100% mortality. CONCLUSION: These findings suggest that patchouli alcohol is one of the chemical constituents responsible for bioactivity of honeysuckle essential oil and some of its fractions. The findings also demonstrate that honey suckle essential oil and its fractions can be exploited as a source of ecofriendly larvicides for mosquito control. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.

Extreme-tolerant bacteria (82 strains; 67 species) isolated during various assembly phases of the Phoenix spacecraft were permanently archived within the U.S. Department of Agriculture's Agricultural Research Service Culture Collection in Peoria, Illinois. This represents the first microbial collection of spacecraft-associated surfaces within the United States to be deposited into a freely available, government-funded culture collection. Archiving extreme-tolerant microorganisms from NASA mission(s) will provide opportunities for scientists who are involved in exploring microbes that can tolerate extreme conditions.