The application of palaeolimnology to evidence‐based lake management and conservation: examples from UK lakes

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Foliar chemistry of juvenile Eucalyptus grandis clones does not predict chemical defence in maturing ramets

The tendency for managers of eucalypt plantations to plant large, homogeneous (i.e. clonal) stands presents a new suite of problems. Perhaps foremost among them is the elevated risk of disease or predation. One way to counter this risk is to select material with high natal resistance, such as material with high concentrations of plant secondary metabolites. This would be much simpler if we could predict future defences from the chemistry of juvenile plants. The present study aimed to determine the relationship between the concentrations of formylated phloroglucinol compounds (FPCs) in the leaves of newly established Eucalyptus grandis (Hill ex Maiden) clones in the nursery and those in the same genetic material in experimental plantations. There was almost no relationship between the concentrations of defensive chemicals in the leaves of newly established E. grandis clones growing in pots in the nursery and of those in the same genetic material growing in plantations. This implies that age effects and probable gene × environment interactions prevent evaluating the defensive qualities of clones until they are several years old and even then the results are site-specific.     

Disturbance changes arbuscular mycorrhizal fungal phenology and soil glomalin concentrations but not fungal spore composition in montane rainforests in Veracruz and Chiapas,Mexico

Mexican montane rainforests and adjacent disturbed areas were studied for disturbance-related spatio-temporal changes to the arbuscular mycorrhizal fungal (AMF) community and soil glomalin concentration. The AMF community functions to both improve plant growth and soil conditions and is thus an important component to the restoration of this forest type to disturbed areas. The study areas included mature rainforests that were converted to pine forests, milpas, pastures and shrub/herbaceous plant communities via burning and logging. Seasonal patterns in AMF spore species richness and sporulation significantly differed across disturbance types at two of the three sites surveyed. Contrasting patterns of sporulation among AMF families across different disturbance types helped to explain how species richness and composition were maintained despite dramatic changes to the host plant community. Meaning, in most cases, disturbance induced changes in when different AMF taxa sporulated but not what taxa sporulated. Only conversion from mature pine–oak–Liquidambar–Persea forests to pine-dominated stands severely reduced AMF spore richness and total sporulation. Surprisingly, in pine-dominant stands no concomitant negative impacts on soil glomalin (MAb32B11 immunoreactive soil protein) concentrations were detected. However, soils of mature forests containing no pines had the highest concentration of glomalin. Conversion to pasture and milpa (diverse cornfield) had a strong negative impact on the concentration of soil glomalin concentrations. In sharp contrast, the same disturbance types improved AMF sporulation and AMF spore richness. It appears that disturbance type, and not AMF community measures used herein, best predicts changes in soil glomalin concentration.     

An analysis of factors underlying hypotrichosis and alopecia in Irish Water Spaniels in the United Kingdom

A survey on the occurrence of dermatoses in the Irish Water spaniel (IWS) was carried out in the United Kingdom. A group of 20 dogs was selected and examined clinically. All dogs had a nonpruritic, noninflammatory, regionalized hair loss affecting the same areas of the body in males and females, although an initial cyclical pattern associated with the oestrus cycle was identified. Hormonal investigations showed features suggestive of an abnormality of steroidogenesis. Histopathology revealed features similar to canine recurrent flank alopecia (CRFA) and follicular dysplasia associated with abnormal melanization, as in colour dilution alopecia, although the clinical features did not correlate with those conditions. Dietary changes improved coat and skin quality in most of the cases in this series but the role of the diet was not investigated further. This study suggests that hair loss in IWS is influenced by dietary factors and sexual hormones. Abnormalities of the steroidogenic pathways may contribute to the severity of the condition.     

Comparison of small-scale and large-scale mixing characteristics: Correlations between small-scale and large-scale mixing and extensional characteristics of wheat flour dough

Mixing measurements provide valuable information about dough strength and stability (STAB) traits. These measurements are important in milling and baking operations, and for varietal selection in wheat breeding programmes. There are several techniques with different sample sizes used for measuring these traits so there is interest in examining the agreement between methods in terms of genotypic (varietal) rankings. This issue has been investigated by using two different mixing methods, a small-scale Mixograph (2 g) and large-scale Farinograph (50 g) using data from a doubled haploid population (190 lines) from a Chara (excellent dough strength)×WW2449 (poor dough strength) cross. The cross was grown in a field trial at the Wagga Wagga Agricultural Institute (WWAI) in 2000. Eleven mixing traits were measured and compared according to a statistical design. The estimated genetic correlation matrix for six of the 11 mixing traits, dough development time (DDT), STAB, mixing tolerance index (MTI), maximum bandwidth (MBW), bandwidth at peak resistance (BWPR) and peak resistance (PR) revealed that for these dough-strength-related parameters, both methods were measuring equivalent traits, although individual parameters had widely different coefficients of variation. In this population, PR was correlated with the extensibility trait length determined by large-scale extension testing. None of the large-scale or small-scale mixing traits was an effective predictor of the small-scale extensibility parameter extensibility at Rmax (Ext_Rmax). The data verified that small-scale Mixograph tests are a robust and efficient alternative to large-scale Farinograph tests for both commercial breeding and research.     

THE COORDINATING ROLE OF LOCAL GOVERNMENT IN AGRICULTURAL DEVELOPMENT WITH SPECIAL REFERENCE TO SMALL-SCALE HOUSEHOLD POND AQUACULTURE IN CHINA 1979–2011

Small-scale household pond aquaculture development has significantly contributed to Chinese food security, poverty reduction, and improved livelihood of farmers. Before the onset of the economic reform in 1979, markets were non-existent. We address the question of the importance of the part played by decentralized government in coordinating the economic activities from a planned to a market-directed economy in the aquaculture sector. In this case study, we have interviewed farmers and officials and used secondary official data in Shandong province. We find that coordination by local government has been crucial in developing small-scale household agricultural and aquaculture production in transitional economy, and enabling the market to become the driving force in the development of household pond aquaculture in rural China. The Chinese experience may bring valuable lessons for other developing countries, where hunger are endemic, and the smallholder farmers are the key target in poverty reduction.     

Assessment of the Bacteriocinogenic Potential of Marine Bacteria Reveals Lichenicidin Production by Seaweed-Derived Bacillus spp.

The objectives of this study were (1) to assess the bacteriocinogenic potential of bacteria derived mainly from seaweed, but also sand and seawater, (2) to identify at least some of the bacteriocins produced, if any and (3) to determine if they are unique to the marine environment and/or novel. Fifteen Bacillus licheniformis or pumilus isolates with antimicrobial activity against at least one of the indicator bacteria used were recovered. Some, at least, of the antimicrobials produced were bacteriocins, as they were proteinaceous and the producers displayed immunity. Screening with PCR primers for known Bacillus bacteriocins revealed that three seaweed-derived Bacillus licheniformis harbored the bli04127 gene which encodes one of the peptides of the two-peptide lantibiotic lichenicidin. Production of both lichenicidin peptides was then confirmed by mass spectrometry. This is the first definitive proof of bacteriocin production by seaweed-derived bacteria. The authors acknowledge that the bacteriocin produced has previously been discovered and is not unique to the marine environment. However, the other marine isolates likely produce novel bacteriocins, as none harboured genes for known Bacillus bacteriocins.     

Variations in Bran Carotenoid Levels within and between Rice Subgroups

Rice (Oryza sativa L.) is a major grain in the human diet and carotenoids are valuable antioxidants. However, little is known about varietal differences in the carotenoid contents of the rice bran. The objective of this study is to determine the relative differences in bran carotenoid levels among all the five subgroups of rice. Measurements were made by a recently described, rapid non-destructive fluorescence quenching method. Confirmation by high performance liquid chromatography (HPLC) after solvent extraction of the bran indicated that the major carotenoid was lutein. Our data showed that carotenoid levels were stable over 10 years of storage. Tropical japonica rice, the most consumed subgroup in the United States, tended to have the lowest levels of carotenoids in the bran while temperate japonicas had the highest. These differences in carotenoid content may open up new opportunities for identifying or breeding rice varieties with higher nutritional value.