Assessing and monitoring the effects of filter material amendments on the biophysicochemical properties during composting of solid winery waste under open field and varying climatic conditions.

Waste management in winery and distillery industries faces numerous disposal challenges as large volumes of both liquid and solid waste by-products are generated yearly during cellar practices. Composting has been suggested as a feasible option to beneficiate solid organic waste. This incentivized the quest for efficient composting protocols to be put in place. The objective of this study was to experiment with different composting strategies for spent winery solid waste. Compost materials consisting of chopped pruning grape stalks, skins, seed and spent wine filter material consisting of a mixture of organic and inorganic expend ingredients were mixed in compost heaps. The filter material component varied (in percentage) among five treatments: T1 (40%) lined, T2 (20%) lined, T3 (0%) lined, T4 (40%) ground material, lined and T5 (40%) unlined. Composting was allowed to proceed under open field conditions over 12months, from autumn to summer. Indicators such as temperature, moisture, enzyme activities, microbial counts, pH, and C/N ratio, were recorded. Generally, season (df=3, 16, P<0.05) had significant effects (df=1, 3, P<0.05) on heap temperature and moisture in all treatments. Similarly, microorganisms (actinobacteria and heterotrophs) varied significantly in all treatments in response to seasonal change (df=3, 16; P<0.05). Enzyme activities fluctuated in accordance with seasonal factors and compost maturity stages, with phosphatases, esterases, amino-peptidases, proteases and glycosyl-hydrolases being most prominent. Compared to treatments T2 and T3, compost treatments with higher percentage waste filter materials (T1, T4 and T5) had higher N (16,100-21,300mg/kg), P (1500-2300mg/kg), K (19,800-28,200mg/kg), neutral pH, and lower C/N ratios (13:1-10:1), which were also comparable with commercially produced composts. Filter materials therefore, appears to be a vital ingredient for composting of winery solid waste.

Anthelmintic and cytotoxic activities of extracts of Markhamia obtusifolia Sprague (Bignoniaceae).

The anthelmintic activity of Markhamia obtusifolia Sprague (Bignoniaceae) leaf extracts was evaluated against the ruminant gastrointestinal nematode parasite Trichostrongylus colubriformis (Nematoda: Strongylida) using the in vitro egg hatch test. Also, the cytotoxic activity of aqueous extracts of M. obtusifolia was evaluated in cell line cytotoxicity assays. The results indicated that the effective concentration (EC(50)) for the water extract of M. obtusifolia leaves (0.46 mg/mL; Confidence Interval [CI] 0.3-0.5mg/mL) was significantly lower than the EC(50) for the acetone extract of M. obtusifolia (0.8 mg/mL; CI 0.7-1mg/mL). Aqueous extracts were twice as potent as the acetone extracts. The EC(90) (0.2mg/mL; CI 0.1-0.02) for thiabendazole (positive control) was significantly lower than the EC(90) for the water extract of M. obtusifolia (10.7 mg/mL; CI 8.3-13.7 mg/mL). In the cytotoxicity bioassay, the lethal concentration (LC(50)) for the aqueous extract of M. obtusifolia was 0.476 mg/mL, which was relatively high (low toxicity) in comparison to the highly toxic berberine (LC(50)=9.80 µg/mL). The current study showed that M. obtusifolia plant extracts possess anthelmintic activity and are relatively non-cytotoxic, thus providing support for their use in traditional veterinary practices.

Attraction response of adult Rhipicephalus appendiculatus and Rhipicephalus pulchellus (Acari: Ixodidae) ticks to extracts from Calpurnia aurea (Fabaceae).

Experiments were carried out to investigate the response of two tick species Rhipicephalus pulchellus Gerstaker, 1873 and Rhipicephalus appendiculatus Neumann, 1901 to three different extracts (acetone, aqueous and oil) of the dried leaves of Calpurnia aurea (Aiton) Benth in both an inverted glass tube and a dual choice T-olfactometer. The oil extract at 50 and 100mg/ml attracted 46.7% and 65.9% of R. appendiculatus, respectively, in the inverted glass tube assay, which was comparable to 47.8% of the attraction-aggregation-attachment pheromone (AAAP) used as positive control. At a dose of 100mg/ml the oil extract attracted 52.4% of R. pulchellus in the T-olfactometer bioassay. The relative attraction of both tick species to plant extract was also tested in semi-field plot experiments using a trap baited with different concentrations of emulsifiable extract of C. aurea. A dose of 100mg/ml attracted 52.2% of R. pulchellus and 44.4% of R. appendiculatus from a distance of 1m while 14.4% of R. pulchellus and 12.2% of R. appendiculatus were attracted from 5m distance at the same dose. Addition of CO(2) to the plant extract-baited-trap at the dose of 100mg/ml increased the range of attraction of adult R. pulchellus (44.4% from 5m distance) and up to 33.3% of adult R. appendiculatus tick from a distance of 4m. The results of this study suggest that extracts from C. aurea can potentially be used as baits in a trap for the control of ticks in the field.

Performance of a Metarhizium anisopliae-treated semiochemical-baited trap in reducing Amblyomma variegatum populations in the field.

Experiments were carried out to evaluate the efficacy of Metarhizium anisopliae (Metsch.) Sorok. (Ascomycota: Hypocreales)-treated semiochemical-baited traps for control of Amblyomma variegatum Fabriscius (Acari: Ixodidae) under field conditions. Unfed A. variegatum adults (118) were seeded in each 100-m plot and allowed to acclimatise for 3 days. On the fourth day (Day 4), an emulsifiable formulation of M. anisopliae (consisting of 49.5% sterile distilled water, fungal conidia, 49.5% corn oil and 1% Tween 80) titrated at 10(9)conidia ml(-1) was applied in semiochemical-baited traps (900 cm(2)) which were placed at five spots within the plot. The control and fungal treatments were repeated after 14 and 28 days soon after rotating the traps clockwise (45 degrees ) in order to cover different sections of the plot. In the control plots, emulsifiable formulation without fungus was applied in the semiochemical-baited traps. Six weeks after the initiation of the experiments, five semiochemical-baited traps (untreated) were deployed in each plot for 3 successive days to trap ticks in the treated and control plots. The percentage of ticks recovered in the fungus-treated plots were significantly lower (31.1+/-5.2%) than in the control plots (85.6+/-3%) (P<0.001), which represented a relative tick reduction of 63.7%. Mortality of 93.8+/-2.3% was observed among the ticks that were recovered from the field and maintained in the laboratory for 2 weeks; while only 3.3+/-0.9% died from the control plots. The results of this study open up the possibility of developing an environmentally friendly and low cost application strategy to control Amblyomma ticks.

The use of a semiochemical bait to enhance exposure of Amblyomma variegatum (Acari: Ixodidae) to Metarhizium anisopliae (Ascomycota: Hypocreales).

Experiments were conducted to explore the use of a semiochemical bait to enhance exposure of Amblyomma variegatum Fabricius (Acari: Ixodidae) to different formulations of the entomopathogenic fungus Metarhizium anisopliae (Metsch.) Sorok. (Ascomycota: Hypocreales). Initially, the relative efficacies of attraction-aggregation-attachment pheromone (AAAP), made up of o-nitrophenol, methyl salicylate and nonanoic acid in the ratio 2:1:8, 1-octen-3-ol and butyric acid, were evaluated in an olfactometer. Only AAAP and 1-octen-3-ol were found to elicit attractive responses to the tick. Simultaneous release of 1-octen-3-ol and AAAP together with CO(2) from a trap in semifield plots attracted up to 94.0+/-6% of adult ticks from a distance of 6m, and up to 24.0+/-5.1% from 8m. Formulations of M. anisopliae (dry powder, oil, and emulsifiable) applied within the trap baited with AAAP, 1-octen-3-ol and CO(2) resulted in high levels of contamination of the ticks attracted to the traps. However, 48h after autoinoculation, 89.1 and 33.3% of conidia were lost in dry powder and oil formulations, respectively. Emulsifiable formulation showed least loss of propagules (17.1%). Samples of ticks attracted to the baited traps were transferred to plastic basins containing grass and maintained for 5 weeks. The experiment was conducted in rainy and dry seasons. Emulsifiable formulation gave the highest relative tick reduction in both seasons: 54.7 and 46.5% in rainy and dry seasons, respectively, followed by oil formulation (32.0 and 23.8%) and powder formulation (38.0 and 24.4%).

In vitro investigation of the toxic effects of extracts of Allium sativum bulbs on adults of Hyalomma marginatum rufipes and Rhipicephalus pulchellus.

The toxic effects of the extracts of Allium sativum (Garlic) were evaluated against adults of Hyalomma marginatum rufipes and Rhipicephalus pulchellus using three types (Types A, B and C) of contact toxicity bioassays. A. sativum bulbs were extracted with acetone, ethanol and dichloromethane (DCM) solvents. Among these three solvents, it is the DCM extract of A. sativum that appears to have anti-tick activity. In the Type A contact toxicity bioassay, DCM extracts of A. sativum demonstrated a high acaricidal bioactivity against H. m. rufipes with 100% of ticks killed in less than an hour, and toxicity persisted to the second day. A weak acaricidal activity of aqueous extracts of A. sativum was observed in the Type B contact toxicity bioassay. In the Type C contact toxicity bioassay, a concentration of 24% w/v of DCM extracts of garlic in sunflower oil (Helianthus annuus) had killed 100% of H. m. rufipes (LC50 = 5.9% w/v) and R. pulchellus (LC50 = 10.3% w/v) by 24 hours post-treatment of ticks. The results obtained from this study suggest that DCM extract of A. sativum is a potential source of novel acaricidal agents.