Production of Bean yellow mosaic virus resistant subterranean clover (Trifolium subterraneum) plants by transformation with the virus coat protein gene

Transgenic lines of subterranean clover were constructed that contained three different Bean yellow mosaic virus (BYMV) coat protein (CP) gene constructs; full-length CP, the core region of the CP, and full-length CP plus the 3′ untranslated region of the viral genome. Transgenic plants containing the full-length and core CP gene constructs showed high and moderate levels of BYMV resistance. Resistance was measured as a lack or amelioration of viral disease symptoms, which was correlated with a reduction in virus levels and yield loss. A range of different resistance phenotypes was observed. They included reduced infection rates, delay and reduction in local lesion development, and delay and reduction in severity of systemic symptom development. Resistance levels were not correlated with transgene mRNA levels and no transgene-encoded protein was detected in any of the transgenic lines. This is the first example of genetically engineered virus resistance in a clover.     

Phenotypic and genetic variation in male genitalia in the seedbug, Lygaeus equestris (Heteroptera)

Male genitalia evolve through sexual selection and, in insects, tend to show negative static allometry, low phenotypic variation, and are usually relatively small. Much less is known about the genetic variation and heritability of male genitalia. Additionally, in instances where the intromittent organ is greatly elongated, it is unclear whether typical patterns of genital scaling and variation also apply. In the present study, we investigated the allometry, variation, and heritability of male genital length in the seedbug, Lygaeus equestris , a species with a greatly elongated intromittent organ (i.e. almost as long as male body size). We found that genital length was negatively allometric, in spite of its great length, and was no more variable than nongenital traits. Additionally, genital length was significantly heritable and had considerable evolvability.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 400–405.     

Test of an environmental flow release in a British Columbia river: does more water mean more fish?

1. Water managers must make difficult decisions about the allocation of streamflows between out‐of‐channel human uses and environmental flows for aquatic resources. However, the effects environmental flows on stream ecosystems are infrequently evaluated. 2. We used a 13‐year experiment in the regulated Bridge River, British Columbia, Canada, to determine whether an environmental flow release designed to increase salmonid productivity was successful. A hierarchical Bayesian model was used to compare juvenile Pacific salmon (Oncorhynchus spp.) abundance before and after the flow release. 3. We found that the total number of salmonids did increase after the release, but most of the gains could be attributed to the rewatering of a previously dry channel located immediately below the dam. In reaches that had flowing water during the baseline period, the response of individual salmon species to the increase in flow was variable, and there was little change in total abundance after the flow release. Our results were inconsistent with both habitat modelling, which predicted a decrease in habitat quality with increasing flow, and holistic instream flow approaches, which imply greater benefits with larger flows. 4. We question whether biotic responses to flow changes can be predicted reliably with currently available methods and suggest that adaptive management or the use of decision tools that account for the uncertainty in the biotic response is required for instream flow decisions when the competing demands for water are great.