Geographic Variation in Wood Specific Gravity: Effects of Latitude, Temperature, and Precipitation

Wood basic specific gravity (SG) was compared at sites located along a gradient from 52°N latitude to the equator. Mean SG increased by 0.0049 per °C mean annual temperature (MAT), and decreased by 0.00017 per cm of mean annual precipitation (MAP). Considered alone, MAT was a better predictor of mean SG across the temperate zone (3-22°C MAT, latitude north of 29°N; r2 = 0.80) than it was across the entire MAT range (r2 = 0.62) or across warm tropical sites alone (MAT > 23°C; r2 = 0.33, p = 0.67). In contrast, MAP considered alone was a better predictor of mean SG in the warm tropical sites (r2 = 0.62) than across all sites (r2 = 0.04, p = 0.39).Variability in SG among the sites was compared using two measures of dispersion: range and standard deviation. As MAT increased across the temperate zone, maximum SG increased and minimum SG remained constant, resulting in an increase in SG range; SG standard deviation, however, remained constant. Both SG range and SG standard deviation increased dramatically in the warm tropical zone relative to the temperate zone, demonstrating that variability in SG in the warm tropics is much greater than would be predicted from greater species richness alone

Extreme Radial Changes in Wood Specific Gravity in Some Tropical Pioneers

Twelve Hampea appendiculata, six Heliocarpus appendiculatus, and twelve Ochroma pyramidale trees from tropical wet forest in Costa Rica were sampled across their radii. Wood from all three species increased linearly in specific gravity from pith to bark. The magnitude of the increase was about 0.1 units of specific gravity per 10 cm of radius, although there were differences between the species and between trees within each species. All three species colonize clearings and disturbed sites, and these extreme changes in specific gravity may be associated with the pioneer habit in the wet forest

Artefatos de preservação em anuros: 27 anos depois

Measurements made on preserved anuran specimens are often used in studies of systematics, ecology and evolution. Here, we examine the effect of preservation on one of the most common measurement of frogs, snout-urostyle length (SUL). Preservation had significant effects on the SUL of 13 of the 14 species of North American frogs included in this study, with all species decreasing in SUL by 0.31-5.62%. Smaller frog species did not shrink proportionally more or less than larger species. Absolute shrinkage was correlated with SUL and was greater in larger species. Within species, percent shrinkage was not significantly correlated with SUL in 10 species, but significantly greater for larger individuals in 3 species, and decreased with size in 1 species. Absolute shrinkage was statistically greater for larger individuals in 4 species. Our results agree with studies of morphological permutations in fish which show that most preservation-related changes take place within the first few months after initial preservation. We suggest that the potential consequences of using preserved specimens in research must be considered and that future studies continue to examine preservation effects, not only on frogs, but on all preserved specimens used in scientific investigations.Medidas tomadas em espécimes preservados são frequentemente usadas em estudos de sistemática, ecologia e evolução. Examinamos aqui o efeito da preservação sobre uma das medidas mais comumente feitas em anuros, o comprimento rostro-clocal (CRC). A preservação teve efeitos significativos sobre o CRC de 13 das 14 espécies de anuros norteamericanos incluídas no estudo, com uma diminuição de 0,31 a 5,62% em todas as espécies. As espécies de menor porte não encolheram proporcionalmente mais nem menos que as espécies maiores. A redução absoluta de tamanho mostrou-se correlacionada com o CRC, tendo sido maior em espécies de maior porte. Dentro de cada espécie, a porcentagem de redução de tamanho não se mostrou significativamente correlacionada com o CRC em 10 espécies, mas foi significativamente maior para os indivíduos de maior porte em três espécies e diminuiu com o tamanho em uma espécie. A redução absoluta de tamanho foi estatisticamente maior para os indivíduos maiores em quatro espécies. Nossos resultados concordam com os dados obtidos em estudos de permutações morfológicas em peixes, que mostraram que a maioria das modificações relacionadas à preservação ocorre durante os primeiros meses após a preservação. Sugerimos que as consequências potenciais do uso de espécimes preservados na pesquisa devem ser consideradas, e que estudos futuros continuem a examinar os efeitos da preservação, não apenas em anuros, mas em todos os espécimes preservados utilizados em investigações científicas

Anuran artifacts of preservation: 27 years later

Measurements made on preserved anuran specimens are often used in studies of systematics, ecology and evolution. Here, we examine the effect of preservation on one of the most common measurement of frogs, snout-urostyle length (SUL). Preservation had significanteffects on the SUL of 13 of the 14 species of North American frogs included in this study, with all species decreasing in SUL by 0.31-5.62%. Smaller frog species did not shrink proportionally more or less than larger species. Absolute shrinkage was correlated with SUL and was greater in larger species. Within species, percent shrinkage was not significantly correlated with SUL in 10 species, but significantly greater for larger individuals in 3 species, and decreased with size in 1 species. Absolute shrinkage was statistically greater for larger individuals in 4 species. Our results agree with studies of morphological permutations in fish which show that most preservation-related changes take place within the first few months after initial preservation. We suggest that the potential consequences of using preserved specimens in research must be considered and that future studies continue to examine preservation effects, not only on frogs, but on all preserved specimens used in scientific investigations

Composition and Diversity of Woody Plants in Tree Plantations Versus Secondary Forests in Costa Rican Lowlands

Efforts to sequester carbon through tree plantations and natural regeneration in the tropics may also provide an opportunity to restore native forest ecosystems. However, the degree to which species composition of native species differs between tree plantations and secondary forests is unknown. In this study, we conducted surveys of woody plants (≥2 cm dbh) in 20 secondary forest and tree plantation plots (30 × 30 m) in a tropical lowland forest landscape. Sites were 8 to 21 years old and were either abandoned cattle pastures (secondary forests) or monoculture tree plantations (Hieronyma alchorneoides and Vochysia guatemalensis) planted for carbon sequestration. We compared species composition, ecological traits, and diversity of woody plants in secondary forests and tree plantations, while accounting for distance from primary forest. Species composition, but not species richness, of the natural regeneration was significantly different in tree plantations and secondary forests. The abundances of understory species, short-lived pioneers, and bat-dispersed species were all higher in secondary forests than in tree plantations. Abundances of canopy species, long-lived pioneers, shade-tolerant species, and dispersal categories besides bats were not associated with forest type. We conclude that tree plantations can alter species composition of regeneration compared with secondary forests perhaps by altering composition of seed disperser assemblages or inhibiting early successional species. © The Author(s) 2018

Effects of experimental lightgaps and topography on enrichment plantings in a central Amazonian secondary forest

Enrichment plantings into secondary forest are an important option in restoring species diversity and ecosystem services. However, little attention has been given to environmental requirements for species performance. This study evaluated the effects of lightgaps and topographic position on the growth and survival of four native tree species (Pouteria caimito, Garcinia macrophylla, Dipteryx odorata and Cynometra bauhiniaefolia) planted into a 26-year old secondary forest originating from abandoned pastures in the central Amazon Basin. Artificial lightgaps and control plots under closed canopy were uniformly distributed on plateaus and bottomlands near water bodies. Seedlings were planted randomly into the plots and monitored for 28 months. Seedling survival rate was high (93%) and did not differ among species. Overall, lightgaps produced a 38% increase in seedling height relative to the controls. Although the four species naturally occur in mature forest, two of the four grew significantly more in lightgaps than in dosed canopy secondary forest. Overall, bottomlands facilitated greater seedling growth in height (38%) relative to plateaus, but only one species exhibited a significant increase. This study shows the importance of the environmental variability generated with canopy openings along the topographic gradient, suggesting that both the selection of species and microsite conditions of planting sites have to be considered important criteria in the recovery of degraded areas

Dung beetle communities: A neotropical-north temperate comparison

Dung beetle communities have been compared across north temperate latitudes. Tropical dung beetle communities appear to be more diverse based on studies using different methodologies. Here, we present results from a standardized sampling protocol used to compare dung beetle communities across five neotropical forests in Brazil and Ecuador and two warm, north temperate forests in Mississippi and Louisiana. Species richness in the tropical forests was three to seven times higher than the temperate forests, as would be expected by studies of other taxa across tropical and temperate latitudes. Average body size in the temperate forests was larger than the tropical forests, as predicted by Bergmann's rule. Dung beetle abundance and volume per trap-day were generally higher in Ecuador than Brazil, and higher in Mississippi than Louisiana, but there were no tropical-temperate differences. Species rank-abundance curves were similar within countries and between countries. Rank-volume distributions indicated a smaller range of beetle body sizes in Ecuador versus Brazil or the USA. Community similarity was high within countries and low between countries. Community differences between Brazil and Ecuador sites may be explained by differences in productivity based on geological age of the soils

The isolation and serology of the "FSA" Brucella melitensis Rev.1 mutant in a flock of sheep

A flock of sheep, known to be infected with the "FSA" mutant of Brucella melitensis Rev. 1, was examined serologically and bacteriologically to determine whether any relationship existed which would help in the control of this infection in the field. An attempt was also made to determine whether vertical transmission occurred. Twenty-one out of 62 sheep were bacteriologically positive. The best organs for isolation were the udder, supramammary lymphnodes and uterus. No significant relationship could be shown between the complement fixation test and bacterial isolation. The absence of any relationship between serological and bacteriological results agrees with a short-lived infection. None of the 24 lambs sacrificed at 5 months showed either serological reactions or were bacteriologically positive, thus no vertical transmission could be shown.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu2014mn201

Genome editing in fruit, ornamental, and industrial crops

The advent of genome editing has opened new avenues for targeted trait enhancement in fruit, ornamental, industrial, and all specialty crops. In particular, CRISPR-based editing systems, derived from bacterial immune systems, have quickly become routinely used tools for research groups across the world seeking to edit plant genomes with a greater level of precision, higher efficiency, reduced off-target effects, and overall ease-of-use compared to ZFNs and TALENs. CRISPR systems have been applied successfully to a number of horticultural and industrial crops to enhance fruit ripening, increase stress tolerance, modify plant architecture, control the timing of flower development, and enhance the accumulation of desired metabolites, among other commercially-important traits. As editing technologies continue to advance, so too does the ability to generate improved crop varieties with non-transgenic modifications; in some crops, direct transgene-free edits have already been achieved, while in others, T-DNAs have successfully been segregated out through crossing. In addition to the potential to produce non-transgenic edited crops, and thereby circumvent regulatory impediments to the release of new, improved crop varieties, targeted gene editing can speed up trait improvement in crops with long juvenile phases, reducing inputs resulting in faster market introduction to the market. While many challenges remain regarding optimization of genome editing in ornamental, fruit, and industrial crops, the ongoing discovery of novel nucleases with niche specialties for engineering applications may form the basis for additional and potentially crop-specific editing strategies.The authors would like to acknowledge funding from MINECO, Spain (PGC2018-097655-B-I00 to P Christou), Generalitat de Catalunya Grant 2017 SGR 828 to the Agricultural Biotechnology and Bioeconomy Unit (ABBU). Work in the Dhingra lab in crop improvement is supported in part by Washington State University Agriculture Research Center Hatch grant WNP00011. ES and FR acknowledge the support received from the Department of Horticulture, BW was supported in part by a Research Assistantship from the Washington State University Graduate School. The authors would also like to thank Drs A. McHughen and H. Quemada for input and clarifications on US genome editing regulations. We would also like to thank the anonymous reviewers for their insightful comments