Chromosome numbers of South African Umbelliferae (Apiaceae)

Chromosome numbers are reported for 12 species from nine genera of South African Umbelliferae, of which seven species and one genus (Itasina) are recorded for the first time. A detailed list of all published chromosome counts for southern African species is also presented, together with a review of the literature. The new data obtained are briefly discussed in the context of the taxonomy and relationships of local Umbelliferae. The counts agree with previous reports except that Annesorhiza appears to have 2n = 22, with or without one additional B-chromosome, and not 2n = 24 as reported in the literature. The number for Itasina (2n = 24) is of considerable interest and indicates that a detailed chromosome study of the South African genera Annesorhiza and Chamarea may yield valuable taxonomic information.     

Carnivora from the Plio-Pleistocene hominin site of Drimolen, Gauteng, South Africa

Drimolen is one of the newest and most productive hominin sites in South Africa, and is dated on faunal grounds between 2.0 Ma to 1.5 Ma. This paper provides the first overview of the Carnivora from Drimolen, updating the previously published preliminary faunal list, and describing all currently prepared craniodental and postcranial material. The Drimolen specimens are described in comparison with other modern and fossil South African carnivore material. The carnivores cover a range of taxa including hyaenids, felids, canids and herpestids. Most notable amongst these are the sabretooth Dinofelis aff. piveteaui craniodental and postcranial remains, which are described in detail, and a Chasmaporthetes nitidula cranium. The genus Chasmaporthetes is found at three other sites in the area - Sterkfontein, Swartkrans and Coopers D. There are two models for the geographic origin of Dinofelis piveteaui, in that it may have arisen in either eastern or southern Africa. These possibilities are discussed in the light of the new South African Dinofelis material, as the Drimolen material appears to represent a more primitive form with affinities with D. piveteaui. Fossil leopard material from Kromdraai B and Drimolen is also discussed, as the metapodia assigned to P. pardus from these two sites are very small, but lie within the variation of modern leopards. Such size differences in fossil postcrania may have implications for the niches that these animals may have occupied in the past.     

Early Acheulean technology in the Rietputs Formation, South Africa, dated with cosmogenic nuclides

An absolute dating technique based on the build-up and decay of ²⁶Al and ¹⁰Be in the mineral quartz provides crucial evidence regarding early Acheulean hominid distribution in South Africa. Cosmogenic nuclide burial dating of an ancient alluvial deposit of the Vaal River (Rietputs Formation) in the western interior of South Africa shows that coarse gravel and sand aggradation there occurred ca 1.57 ± 0.22 Ma, with individual ages of samples ranging from 1.89 ± 0.19 to 1.34 ± 0.22 Ma. This was followed by aggradation of laminated and cross-bedded fine alluvium at ca 1.26 ± 0.10 Ma. The Rietputs Formation provides an ideal situation for the use of the cosmogenic nuclide burial dating method, as samples could be obtained from deep mining pits at depths ranging from 7 to 16 meters. Individual dates provide only a minimum age for the stone tool technology preserved within the deposits. Each assemblage represents a time averaged collection. Bifacial tools distributed throughout the coarse gravel and sand unit can be assigned to an early phase of the Acheulean. This is the first absolute radiometric dated evidence for early Acheulean artefacts in South Africa that have been found outside of the early hominid sites of the Gauteng Province. These absolute dates also indicate that handaxe-using hominids inhabited southern Africa as early as their counterparts in East Africa. The simultaneous appearance of the Acheulean in different parts of the continent implies relatively rapid technology development and the widespread use of large cutting tools in the African continent by ca 1.6 Ma.     

Response of cold-acclimated,farmed South African abalone (Haliotis midae) to short-term and long-term changes in temperature

In its natural environment, the South African abalone, Haliotis midae, occurs at average monthly water temperatures between 12 and 21 °C. In the present study we aimed to describe selected physiological and molecular responses of winter acclimated, cultured H. midae after acute and chronic exposure to 16, 19 and 22 °C.     

A renaissance in herbal medicine identification: From morphology to DNA

Numerous adverse reactions have arisen following the use of inaccurately identified medicinal plant ingredients, resulting in conditions such as aristolochic acid nephropathy and herb-induced poisoning. This problem has prompted increased global concern over the safety of herbal medicines. DNA barcoding, a technique aiming at detecting species-specific differences in a short region of DNA, provides a powerful new tool for addressing this problem. A preliminary system for DNA barcoding herbal materials has been established based on a two-locus combination of ITS2 + psbA–trnH barcodes. There are 78,847 sequences belonging to 23,262 species in the system, which include more than 95% of crude herbal drugs in pharmacopeia, such as those of China, Japan, Korea, India, USA, and Europe. The system has been widely used in traditional herbal medicine enterprises. This review summarizes recent key advances in the DNA barcoding of medicinal plant ingredients (herbal materia medica) as a contribution towards safe and efficacious herbal medicines.     

Modulation of ethanol toxicity by Asian ginseng (Panax ginseng) in Japanese ricefish (Oryzias latipes) embryogenesis

Alcohol consumption by women during pregnancy often induces fetal alcohol spectrum disorder (FASD) in children who have serious central nervous system (CNS), cardiovascular, and craniofacial defects. Prevention of FASD, other than women abstaining from alcohol drinking during pregnancy, is not known. A limitation of the use of synthetic anti-alcoholic drugs during pregnancy led us to investigate herbal products. In particular, many plants including Asian ginseng (Panax ginseng) have therapeutic potential for the treatment of alcoholism. We used Japanese ricefish (medaka) (Oryzias latipes), an animal model of FASD, for identifying herbal medicines that can attenuate ethanol toxicity. Fertilized eggs in standard laboratory conditions were exposed to ginseng (PG) root extract (0–2 mg/mL) either 0–2 (group A) or 1–3 (group B) day post fertilization (dpf) followed by maintenance in a clean hatching solution. The calculated IC₅₀ as determined 10 dpf in A and B groups were 355.3 ± 1.12 and 679.7 ± 1.6 μg/mL, respectively. Simultaneous exposure of embryos in sub-lethal concentrations of PG (50–200 μg/mL) and ethanol (300 mM) for 48 h disrupted vessel circulation and enhanced mortality. However, PG (100 μg/mL) may partially protect trabecular cartilage (TC) deformities in the neurocranium in B group embryos induced by ethanol (300 mM). To understand the mechanism, embryonic ethanol concentration was measured at 2 dpf and adh5, adh8, aldh2, aldh9a, catalase, GST, and GR mRNAs were analyzed at 6 dpf. It was observed that although ethanol is able to reduce adh8 and GST mRNA contents, the simultaneous addition of PG was unable to alter ethanol level as well as mRNA contents in these embryos. Therefore, antagonistic effects of PG on ethanol toxicity are mediated by a mechanism which is different from those regulating ethanol metabolism and oxidative stress.     

Cercopithecidae from the Pliocene Chiwondo beds, Malawi-rift

There are a total of 16 fossil cercopithecid specimens, representing at least 10 individuals, from the Chiwondo Beds of northern Malawi. The majority of this material is derived from the Middle Pliocene Unit 3A, but one specimen is from the Early Pliocene Unit 2. This latter specimen is from a papionin of indeterminate genus similar in size to Parapapio ado and Pliopapio alemui. Among the specimens from Unit 3A, two species can be diagnosed: an indeterminate species of Theropithecus, and a species of Parapapio similar in dental size to P. broomi. Neither of the genera from Unit 3A are exclusive to either East Africa or South Africa. Their relative abundances, however, are more similar to Middle Pliocene South African sites where Parapapio is the most common primate genus, and Theropithecus is comparatively rare. This is in contrast to similarly-aged East African sites where Theropithecus is by far the most abundant genus.     

Resilience and elasticity of intertidal communities in response to harvesting of the alien mussel Mytilus galloprovincialis

Besides the direct impacts of exploitation on target species, indirect effects on non-target species are unavoidable and find expression in changes in community structure. We quantified the effects of experimental harvesting of Mytilus galloprovincialis on intertidal communities on the South African west coast. In the mid- and low-shore, four months of harvesting at intensities greater than F = 0.3 and F = 0.6 respectively, resulted in significant changes in community composition. These changes were driven by progressively greater spatial dominance by the macroalgae Cladophora flagelliformis, Porphyra capensis and Ulva species as harvesting intensity increased. Four months after cessation of harvesting, community structure had not recovered and even areas subjected to as little as F = 0.3 supported significantly altered communities in both zones. The fact that substantial community changes were induced by even low-intensity exploitation is indicative of low resilience to harvesting. The densities and cover of the dominant taxa returned to a pre-harvest state 16 months after the cessation of harvesting, but multivariate analyses indicated that the overall community composition required 32 months for Cover Letter full recovery. Although these communities displayed elasticity within three years, it is recommended that should a M. galloprovincialis fishery be established in the region, harvesting be implemented at a maximum intensity of F = 0.3. This approach would maximise yields and protect associated intertidal communities.     

Diapause induction, maintenance and termination in the rice stem borer Chilo suppressalis (Walker)

The rice stem borer, Chilo suppressalis, enters facultative diapause as fully grown larvae in response to short-day conditions during the autumn. Our results showed that the critical night length for diapause induction in C. suppressalis was between 10 h 22 min and 10 h 45 min at 22, 25 and 28 °C, 11 h 18 min at 31 °C, and between 10 h 5 min and 10 h 20 min under field conditions (average temperature ranged from 27.2 to 30.7 °C). The diapause incidence declined in ultra-long nights (18-22 h scotophases) and DD, and increased in ultra-short nights (2-6 h scotophases) and LL. Moreover, we found that the third instar was the stage most sensitive to the photoperiod, and night length played an essential role in the initiation of diapause. Night-interruption experiments with a 1-h light pulse at LD 12:12 (light 12:dark 12) exhibited two troughs of diapause inhibition, with one occurring in early scotophase and the other in late scotophase. Field observations for six years showed that most larvae entered winter diapause in August in response to declining day lengths, despite the high temperatures prevailing during August. By periodically transferring the field-collected overwintering larvae to different photoperiods and temperatures, the results showed that photoperiod had a significant influence on diapause development during the early phase of diapause, while high temperature significantly accelerated the termination of larval diapause.     

Application of vibrational spectroscopy in the quality assessment of Buchu oil obtained from two commercially important Agathosma species (Rutaceae)

Quality assessment of natural raw materials and derived consumer products is often done using conventional analytical techniques such as liquid and gas chromatography which are expensive and time consuming. This paper reports on the use of vibrational spectroscopy techniques as possible alternatives for the rapid and inexpensive assessment of the quality of ‘buchu oil’ obtained from two South African species; Agathosma betulina and Agathosma crenulata belonging to the Rutaceae family. Samples of A. betulina (55) and A. crenulata (16) were collected from different natural localities and cultivation sites in South Africa. The essential oil was obtained by hydrodistillation and scanned on Near infrared (NIR), mid infrared (MIR) and Raman spectrometers. The spectral data obtained was processed using chemometric techniques and orthogonal partial least squares discriminant analysis (OPLS-DA) was used to clearly differentiate between A. betulina and A. crenulata. The OPLS-DA technique also proved to be a useful tool to identify wave regions that contain biomarkers (peaks) that contributed to the separation of the two species. The three spectroscopy techniques were also evaluated for their ability to accurately predict the percentage composition of seven major compounds that occur in A. betulina ‘buchu’ oil. Using GC–MS reference data, calibration models were developed for the MIR, NIR and Raman spectral data to predict/profile the major compounds in ‘buchu oil’. A comparison of the three spectroscopy techniques showed that MIR together with PLS algorithms produced the best model (R²X = 0.96; R²Y = 0.88 and Q²Ycum = 0.85) for the quantification of six of the seven major oil constituents. The MIR model showed high predictive power for pseudo-diosphenol (R² = 0.97), isomenthone (R² = 0.97), menthone (R² = 0.90), limonene (R² = 0.91), pulegone (R² = 0.96) and diosphenol (R² = 0.85). These results illustrate the potential of MIR spectroscopy as a rapid and inexpensive alternative to predict the major compounds in buchu oil.     

Neospora caninum - How close are we to development of an efficacious vaccine that prevents abortion in cattle?

Neospora caninum is a protozoan parasite that causes abortion in cattle around the world. Although the clinical signs of disease in both dogs and cattle have now been recognised for over 20 years, treatment and control options are still limited, despite the availability of a commercial vaccine in some countries of the world. The case for an efficacious vaccine has not been convincingly waged by farmers, veterinarians and other members of the agricultural and rural communities. In recent times, however, economic modelling has been used to estimate the industry losses due to Neospora-associated abortion, providing, in turn, the business case for forms of control for this parasite, including the development of vaccines. In this review, we document progress in all areas of the vaccine development pipeline, including live, killed and recombinant forms and the animal models available for vaccine evaluation. In addition, we summarise the main outcomes on the economics of Neospora control and suggest that the current boom in the global dairy industry increases the specific need for a vaccine against N. caninum-associated abortion.     

Antimicrobial activity and in vitro cytotoxicity of selected South African Helichrysum species

The antimicrobial activity of 35 indigenous South African Helichrysum species was determined against six microorganisms. Seven of the 36 chloroform:methanol (1:1) extracts (leaf and stem extracts for all plants and an additional flower extract for H. rugulosum) exhibited minimum inhibitory concentration (MIC) values lower than 0.1 mg/ml against Bacillus cereus and/or Staphylococcus aureus. The in vitro cytotoxicity [against transformed human kidney epithelial (Graham) cells, MCF-7 breast adenocarcinoma and SF-268 glioblastoma cells] of these extracts was also determined at a concentration of 0.1 mg/ml using the sulforhodamine B (SRB) assay. For seven species less than 25% growth was observed for the Graham and MCF-7 cell lines at the test concentration.     

Effects of experimental harvesting on recruitment of an alien mussel Mytilus galloprovincialis

Successful fisheries management is underpinned by an understanding of the processes that underlie the population dynamics of exploited stocks. This study considered the effects of experimental harvesting on recruitment of Mytilus galloprovincialis along the west coast of South Africa, where harvesting of this alien species is being contemplated. In particular, the role of settlement habitat availability in the form of adult mussels was analysed. To track the effects of a spectrum of harvesting intensities, five treatments were implemented: F = 0 (i.e. a control), F = 0.3, F = 0.6, F = 0.9 and F = 1. At these harvesting intensities 0%, 30%, 60%, 90% or 100% of mussel biomass was removed respectively at the outset of the experiment. A significant negative exponential relationship (p < 0.01) was found between M. galloprovincialis recruit density and harvesting intensity, with intensities greater than F = 0.3 dramatically reducing recruitment. This pattern was recorded throughout the intertidal zone and remained temporally constant over 2 years. Significant positive linear relationships (p < 0.01) between recruit density and adult mussel biomass or density indicate a strong correlation between availability of settlement habitat and recruitment. It is likely that the high recruit density recorded at low harvesting intensities (2000-20 000 per 0.01 m²) exceeds the level required for population maintenance. However, if settlement habitat is eliminated or significantly reduced, as was achieved by F = 0.3 or above, recruitment may become limiting. Thus, to protect stock replenishment, harvesting of M. galloprovincialis in this region should take place at intensities less than F = 0.3.     

Identification of bovine NPC1 gene cSNPs and their effects on body size traits of Qinchuan cattle

NPC1 gene is an important gene closely related to the Niemann–Pick type C (NPC). Mutations in the NPC1 gene tend to cause Niemann–Pick type C, a lysosomal storage disorder. Previous studies have shown that NPC1 protein plays an important role in subcellular lipid transport, homeostasis, platelet function and formation, which are basic metabolic activities in the process of development. In this study, to explore the association between the NPC1 gene variation and body size traits in Qinchuan cattle, we detected four novel coding single nucleotide polymorphisms (cSNPs) in the bovine NPC1 gene, including one missense mutation (SNP1) and three synonymous mutations (SNP2, SNP3 and SNP4). Population genetic analyses of 518 individuals and association correlations between cSNPs and bovine body size traits were conducted in this research. A missense mutation at SNP1 locus was found to be significantly related to the heart girth, hip width and body weight (P < 0.01 or P < 0.05, 3.5-year-old). Two synonymous mutations at SNP2 and SNP3 loci also showed significant effects on hip width (P < 0.05, 3.5-year-old). One synonymous mutation at SNP4 locus showed significant effect on body weight (P < 0.05, 2.0-year-old). Combined haplotypes H₂H₆ and H₆H₆ showed significant effects on body size traits such as heart girth, hip width, and body weight (3.5-year-old, P < 0.01 or P < 0.05). This study provides evidence that the NPC1 gene might be involved in the regulation of bovine growth and body development, and may be considered as a candidate gene for marker assisted selection (MAS) in beef cattle breeding industry.     

Genetic diversity of silver pomfret (Pampus argenteus) populations from the China Sea based on mitochondrial DNA control region sequences

The genetic diversity of silver pomfret (Pampus argenteus) from the Bohai, East China, and South China Seas was investigated using mitochondrial DNA (mtDNA) control region sequence data. We found high levels of variation with 17 haplotypes among the 45 individuals (h = 0.88, π = 0.006). AMOVA analysis detected significant structuring among China Sea silver pomfret (P < 0.05, F_ST = 0.050), which indicates significant genetic differentiation. No significant differentiation between Bohai Sea and East China Sea samples was detected (P > 0.05). Whether silver pomfret from the South China Sea exhibit a different demographic history than those from the Bohai and East China Seas remains to be determined.     

Vegetation patterns and spontaneous regression of Caulerpa taxifolia (Vahl) C. Agardh in Malinska (Northern Adriatic,Croatia)

The green alga Caulerpa taxifolia was recorded at Malinska in 1994 and this actually represents the highest northern latitude (45°7′30″N) at which this invasive alga has been found in the world. The alga was widespread at four sites from which it was eradicated by suction pumps during 1996 and 1997. However, it immediately and intensively recolonized all but one site. Throughout 1998 and 1999 the renewed vegetation showed consistent seasonal patterns. The alga nearly disappeared in April and May while regenerating from over-wintering parts of the thalli in summer. The maximum development occurred in autumn and winter with values of biomass (around 200 g dry weight m⁻²) and frond number (around 2000 m⁻²) generally lower than those reported for the north-western Mediterranean. Values for the frond length (10–18 cm) were in the same range as those in the north-western basin. Throughout 1998 and 1999 the biomass was closely correlated to frond number and length (adjusted R² = 0.90). During the following years C. taxifolia entered a phase of regression. The total colonized area, which amounted to several thousands of square metres in 1998, spontaneously declined in 2000 and 2001 so that only several thalli were found in 2004 during a detailed survey of the settlement. No major changes in winter seawater temperatures, ranging from 9.5 to 10.5 °C, were observed in the area from 1994 to 2004. Thus, other unknown processes could likely play a role on specific vegetation patterns of C. taxifolia in Malinska. Accordingly, it is difficult to explain why the still surviving thalli did not proliferate during the favourable summer–autumn period.     

Diurnal, seasonal and sex variations in rectal temperature of African giant rats (Cricetomys gambianus, Waterhouse)

(1)

Rectal temperature (T_r) was measured in captive African giant rats (Cricetomys gambianus, Waterhouse), live-trapped in the Savannah during the harmattan, hot-dry and rainy seasons with the aim of determining diurnal, seasonal and sex patterns.

(2)

Mean (±SEM) T_r in the morning (37.16±0.04 °C) was lower (P<0.001) than the afternoon (37.49±0.03 °C) and evening (37.66±0.03 °C). There was no significant difference (P>0.05) between afternoon and evening T_r during the harmattan and rainy seasons, but the difference was significant (P<0.001) during the hot-dry season. Overall T_r was higher (P<0.001) during the hot-dry (38.03±0.03 °C) than harmattan (37.17±0.03 °C) and rainy (37.21±0.03 °C) seasons. T_r of bucks was lower than that of does (P<0.0001) during the harmattan and rainy seasons, but sex difference during the hot-dry season was not significant (P>0.05).

(3)

Base-line T_r values for the African giant rats are shown for the first time. Season, time of day and sex influence fluctuations in T_rs of African giant rats, and should be considered during diagnostic and clinical evaluations.

     

Temperature limits to early development of the New Zealand sea urchin Evechinus chloroticus (Valenciennes, 1846)

Seawater temperature is an important environmental factor for the early life stages of marine invertebrates. In this study we evaluated and described the effects of temperature during early development of E. chloroticus, identifying the optimum temperature range and upper thermal limit for successful development. The temperature range evaluated was between 15–24 °C which included the normal seawater temperatures during the spawning season in northern New Zealand, as well as the highest temperature projected by the IPCC for this region due to global warming (1–3 °C by the year 2100). Gametes from several females and males were used in the experiment. Fertilization was carried out at different temperatures and development was monitored at different time points after fertilization in each temperature. The development rate of E. chloroticus increased with an increase in seawater temperature. However, at temperatures higher than 21.5 °C the amount of abnormal development reached ∼30%. The optimum temperature for early development was between 15–21 °C, whereas the upper thermal limit was ∼24 °C. Therefore, early development of E. chloroticus is negatively affected by an increase in seawater temperature of ∼3–4 °C above current seawater temperature levels in northern New Zealand. The thermal sensitivity of early life stages of E. chloroticus could affect survival rates during early development of this species in a global warming scenario, which could impair recruitment in populations which are exposed to higher temperatures, leading to possible distributional shifts of this species.     

Parnassius apollo last-instar larvae development prediction by analysis of weather condition as a tool in the species’ conservation

Parnassius apollo (Lepidoptera: Papilionidae) has already disappeared or is under threat of extinction in many of its former habitats. It has been documented that weather conditions – anomalies in particular – contributed to this process. In this study, we combined developmental data obtained previously for the last-instar Apollo larvae (collected in 1996, 1997, and 2003) with corresponding meteorological data to assess the effects of ambient temperature and rainfall episodes on the duration and the completion of the instar. For comparing the temperature effect, we applied the degree-day concept. We found significant positive correlation between the number of rainy days during the instar development (x) and its duration time (y): y = 8.293 + 0.936x (± 2.813) (r = 0.662, P < 10⁻⁷). Logarithmic transformation of the growth curves of the last-instar Apollo larvae revealed that there was no difference in growth among females; however, there was slower growth of males in 2003 in comparison to 1996. Growth (y) of female Apollo larvae as a function of instar duration (x) can by described by one common equation, irrespectively of the year: y = 317.6 + 502.3 lnx (± 263.3) (r = 0.82, P < 10⁻⁴).     

The influence of the fungal pathogen Mycocentrospora acerina on the proteome and polyacetylenes and 6-methoxymellein in organic and conventionally cultivated carrots (Daucus carota) during post harvest storage

Many carrots are discarded during post harvest cold storage due to development of fungal infections, caused by, e.g., Mycocentrospora acerina (liquorice rot). We compared the susceptibility of carrots grown under conventional and organic agricultural practices. In one year, organically cultivated carrots showed 3 × to 7 × more symptoms than conventionally cultivated, when studying naturally occurring disease at 4 and 6 months, respectively. On the other hand, we have developed a bioassay for infection studies of M. acerina on carrots and observed that organic roots were more susceptible after one month of storage than conventional ones, but no differences were apparent after four or six months storage. Levels of polyacetylenes (falcarinol, falcarindiol and falcarindiol-3-acetate) did not change, whereas the isocoumarin phytoalexin (6-methoxymellein) accumulated in infected tissue as well as in healthy tissue opposite the infection. The proteomes of carrot and M. acerina were characterized, the intensity of 33 plant protein spots was significantly changed in infected roots including up regulation of defence and stress response proteins but also a decrease of proteins involved in energy metabolism. This combined metabolic and proteomic study indicates that roots respond to fungal infection through altered metabolism: simultaneous induction of 6-methoxymellein and synthesis of defence related proteins.