Effects of Agrobacterium tumefaciens-mediated transformation and tissue culture on storage lipids in Brassica napus

The variation obtained in storage fatty acids induced by the procedures of tissue culture and transformation with Agrobacterium tumefaciens was investigated and compared in rapeseed, Brassica napus, cv. Hanna. An increased variation in the fatty acid profiles was noted after tissue culture and transformation compared with plants derived directly from seeds. In the second generation of rapeseed transformants, T₂, the content of oleic acid ranged from 39–72%, 12–31% for linoleic acid and 7–16% for linolenic acid. This could be compared with the oleic acid content in the T₂ generation of tissue culture-derived plants which ranged between 47–76% and in seed-derived material where oleic acid ranged between 55–69%.In the T₃ generation the ranges in transgenic seeds were decreased but still larger than in the seed derived plants. The range in transgenic plants was 49–64% for oleic acid, 20–28% for linoleic acid and 9–18% for linolenic acid. The most extreme individuals, both highest and lowest in the common fatty acids, were found in the group of transformed plants independent of generation. The total lipid content was also affected by the two treatments and seeds with the lowest and highest lipid content were both found among the transformed plants. In conclusion, care should be taken to use proper controls when performing transformation experiments in order to distinguish variation in the fatty acid profiles induced by the transformation procedure and tissue culture treatments from the changes due to transgenic expression. This revised version was published online in July 2006 with corrections to the Cover Date.     

Historical and contemporary habitat use of sperm whales around the Galápagos Archipelago: Implications for conservation

1. Sperm whales have occupied the waters off the Galápagos Islands, Ecuador, for at least the past 200 years. During the 19^th century, they were the target of intensive whaling that severely depleted the population. In recent times, after commercial whaling ended, sperm whales in the region remain vulnerable to multiple threats, especially potential entanglement in fishing gear, which may hinder their ability to recover from the whaling era.
2. As a highly mobile, long-lived species, long-term analysis of the habitat use of sperm whales is necessary to establish effective conservation and management strategies. Here, contemporary (1985–2014) and historical (1830–1850) sperm whale habitat use off the Galápagos Islands was analysed and contrasted to the extent of the Galápagos Marine Reserve (GMR). Contemporary habitat use and its variability over time were modelled as a function of geographic, oceanographic, and topographic variables using generalized additive models.
3. The fine-scale habitat (<50 km) used by sperm whales was associated with topographic (i.e. depth and slope) and oceanographic characteristics (i.e. relative sea surface temperature and standard deviation of sea surface temperature), but these preferences varied over time.
4. While historical and contemporary data indicate that sperm whale habitat primarily occurred within the boundaries of the GMR, in recent years, whales were found up to 30.1% of the time outside the GMR, potentially overlapping with commercial fisheries operating in the area.
5. The dynamic nature of the relationship of this nomadic species with its habitat highlights the need of large-scale conservation efforts across the Eastern Tropical Pacific region, including the wide-scale enforcement of regulations requiring the use of Automatic Identification System in fishing vessels, the promotion of on-board fisheries observer programmes, the development of adaptive management strategies, and international collaboration to identify and mitigate threats.

     

CEREBRAL VENTRICULAR SIZE IN DEVELOPING NORMAL KITTENS MEASURED BY ULTRASONOGRAPHY

To evaluate the age of fontanelle closure of normal kittens and the size of their lateral ventricles, 50 ultrasonographic examinations using the bregmatic fontanelle as an acoustic window were made. Seven kittens, laboratory animals, were included in the study. To verify the location of the lateral ventricle, two of the kittens were sacrificed as neonates. In one of them ink was injected prior to autopsy into one lateral ventricle under sonographic guidance. In a longitudinal study of five of the kittens, the skull depth and the depth of the central part of the lateral ventricle reproduced in a longitudinal view could be measured up to the age of about 5 months. During that period, the skull depth increased from a median value of 1.95 cm (1.92-1.98) in a seven-day-old cat to 2.58 cm (2.52-2.59) in a 154-day-old cat, while the afore-mentioned ventricle values increased from 0.3 mm to 1.1 mm.     

Collaborative scenario modeling reveals potential advantages of blending strategies to achieve conservation goals in a working forest landscape

Context

Broad-scale land conservation and management often involve applying multiple strategies in a single landscape. However, the potential outcomes of such arrangements remain difficult to evaluate given the interactions of ecosystem dynamics, resource extraction, and natural disturbances. The costs and potential risks of implementing these strategies make robust evaluation critical.

Objectives

We used collaborative scenario modeling to compare the potential outcomes of alternative management strategies in the Two Hearted River watershed in Michigan’s Upper Peninsula to answer key questions: Which management strategies best achieve conservation goals of maintaining landscape spatial heterogeneity and conserving mature forests and wetlands? And how does an increase in wildfire and windthrow disturbances influence these outcomes?

Methods

Scenarios were modeled using the VDDT/TELSA state-and-transition modeling suite, and resulting land cover maps were analyzed using ArcGIS, FRAGSTATS, and R statistical software.

Results

Results indicate that blending conservation strategies, such as single-ownership forest reserves and working forest conservation easements in targeted areas of the landscape, may better achieve these goals than applying a single strategy across the same area. However, strategies that best achieve these conservation goals may increase the sensitivity of the landscape to changes in wildfire and windthrow disturbance regimes.

Conclusions

These results inform decision-making about which conservation strategy or combination of strategies to apply in specific locations on the landscape to achieve optimum conservation outcomes, how to best utilize scarce financial resources, and how to reduce the financial and ecological risks associated with the application of innovative strategies in an uncertain future.