Immunodiscrimination Between Native and Recombinant Somatotropin: a Possible Pathway?

Veterinary Research Communications -     

Species pool,human population,and global versus regional invasion patterns

Context

Biological invasions are among the greatest global and regional threats to biomes in the Anthropocene. Islands, in particular, have been perceived to have higher vulnerability to invasions. Because of the dynamic nature of ongoing invasions, distinguishing regional patterns from global patterns and their underlying determinants remains a challenge.

Objectives

We aim to comparatively examine global versus regional patterns of plant invasions and the possible underlying mechanisms. We also test whether there is a difference in degree of invasion and invasibility between mainland areas and islands.

Methods

We compiled and analyzed data from published sources for 100 mainland areas (i.e., regions, countries, states, and provinces) and 89 islands across the globe.

Results

We find that (1) the pool of exotic species available intrinsically decreases as area of the land considered increases (at global scale, all is native), thus global invasion patterns assessed by exotic fraction (proportion of exotics) are primarily determined by land area; (2) because “exotic” is defined relative to the borders of the target region, “boundary effects” can result in regional differences in invasion patterns without any ecological processes being involved; and (3) human population density is closely linked to exotic fraction within regions that are defined by a single administrative border.

Conclusions

There were clear differences between global and regional patterns of plant invasions. We observed no difference in the exotic fraction-area relationship between mainland areas and islands, supporting what we refer to as the “island-mainland continuum concept” (i.e., no clear separation in the degree of invasion between islands and mainland area with regard to the effects of area). Because of scale-dependency in many observed patterns, future focus should be placed on the links between local, regional, and global invasion patterns.

     

An Immunoenzymatic Method to Measure IGF-1 in Milk

Veterinary Research Communications - Guidi, A., Castigliego, L., Iannone, G., Armani, A. and Gianfaldoni, D., 2007. An immunoenzymatic method to measure igf-1 in milk. Veterinary Research...     

Beneficial effects of Neotyphodium tembladerae and Neotyphodium pampeanum on a wild forage grass

Asexual, vertically transmitted fungal endophytes of the genus Neotyphodium are considered to enhance growth, stress resistance and competitiveness of agronomic grasses, but have been suggested to have neutral or deleterious effects on wild grasses. We studied whether the associations between Bromus auleticus and their endophytes, Neotyphodium pampeanum and Neotyphodium tembladerae, are beneficial for this wild forage grass native to South America. In a greenhouse experiment, 3‐month‐old endophyte‐infected plants (E+) showed enhanced growth relative to their endophyte‐free counterparts (E?). In a one‐year‐long experiment in the field, E+ plants showed higher survival and regrowth rate, and produced more biomass and seeds than E? plants. Only with respect to the seed output did N. tembladerae seem to be detrimental, whereas N. pampeanum did not affect this parameter. No differences were observed with respect to the germination of seeds produced by E+ or E? plants. Loline alkaloids were detected in N. pampeanum‐infected plants. Our results show that, similar to results with agronomic grasses, in wild grasses, the symbiosis with Neotyphodium species could be mutualistic.