First records of two mealybugs,Maconellicoccus hirsutus (Green) and Phenacoccus peruvianus Granara de Willink,in Tunisia and the North of Africa

During the summer and autumn of 2014 the mealybugs Maconellicoccus hirsutus (Green, 1908) (Hemiptera: Pseudococcidae) and Phenacoccus peruvianus Granara de Willink, 2007 (Hemiptera: Pseudococcidae) were observed in different localities of Sousse (Tunisia). This is the first record for both of these species in Tunisia and in North Africa. For M. hirsutus, this was also the first record of the species in a Western Mediterranean country. It was observed on Hibiscus rosa‐sinensis (Malvacae). P. peruvianus was collected from Bougainvillea glabra (Nyctaginaceae) and Citharexylum quadrangularis (Verbenacae).     

Attenuation of Schistosoma mansoni cercarial infectivity to albino mice by methanol extract of some plant species

This study elucidates the activity of certain plants’ methanol extract: Anagallis arvensis, Solanum nigrum (green fruits), Chenopodium ambrosioides, Calendula officinalis and Sesbania sesban, on the infectivity of S. mansoni cercariae to albino mice. Then, some parasitological parameters, e.g. the worm load/mouse, number of ova/g tissue in liver and intestine and the developmental stages of ova in the small intestinal wall (Oogram) of infected mice were determined. In addition, certain biochemical parameters of serum from infected mice (total protein, albumin, the activities of AlT, AsT, AcP and AkP enzymes) were, also, recorded.The results showed that exposure of S. mansoni cercariae for 30 min to the tested plants’ methanol extract before mice infection has a higher suppressive effect on their infectivity to albino mice then those exposed to this extract during mice infection. The number of worms recovered/infected mouse and the number of ova/g tissue from liver and intestine of mice groups infected with cercariae exposed to the tested plants’ methanol extract either pre- or during mice infection were less than those of infected control groups (e.g. the reduction rates of worm load/mouse and number of ova/g tissue in the intestine were 46.1% and 76.8%, respectively, for mice infected with cercariae exposed to 5 ppm of A. arvensis during mice infection).The results, also, indicated that exposing S. mansoni cercariae to methanol extract of the experimental plants either pre- or during mice infection reduced the activities of the enzymes AlT, AsT, AcP and AkP that were elevated in mice infected with untreated cercariae, meanwhile, the concentrations of total protein and albumin were increased in the serum of mice infected with these treated cercariae in comparison with those of mice group infected with untreated cercariae.     

Role of Ammonium to Limit Nitrate Accumulation and to Increase Water Economy in Wild Swiss Chard

ABSTRACT

The present study was performed to characterize the interaction between nitrogen (N) form and availability with respect to growth, water relations, and mineral nutrition of wild swiss chard (Beta macrocarpa Guss). Plants were cultured hydroponically with two levels of N concentrations, high-N (2.5 mM) or low-N (0.5 mM), added as nitrate (NO^? ₃) or ammonium (NH⁺ ₄). At high N, growth was affected significantly by N form. If the NO^? ₃ medium was considered as control, the use of NH⁺ ₄ decreased dry matter production and leaf area by ca. 35%. Use of NH⁺ ₄ led to water economy and did not affect the nutrient content of the plant tissues. Compared to growth with high N, plants growth fell in either low- NO^? ₃ or low- NH⁺ ₄ medium. In this case, the difference between the two N sources was not significant. Our results showed that the replacement of NO^? ₃ by NH⁺ ₄ as the N source decreased the NO^? ₃ concentration in consumable leaves and increased the water use efficiency.     

A stranding record of the short-beaked common dolphin (Delphinus delphis) in Algerian West Coast,during 2008–2012

1. Marine mammals stranding data provide valuable information on causes of mortality for cetacean populations. The aim of this study was to investigate the characteristics of the stranding events of common dolphins along the Algerian west coast, and estimate the proportion of human vs. non-human induced mortality of the population.
2. Between 2008 and 2012, out of the 52 cetacean stranding records along the Algerian west coast, common dolphins (Delphinus delphis) were recorded in 14 cases. All recorded strandings were of individual cases with no mass strandings registered during the reported period.
3. To examine the proportion of human and non-human induced mortality affecting this population, necropsies were conducted. In 10 cases, an interaction with some type of fishing gear had occurred; in three, there was no link with human activity; and in one case, it was not possible to determine the cause of death due to the condition of the carcass (severely decomposed).

     

Effect of tannins from Quercus suber and Quercus coccifera leaves on ethanol-induced gastric lesions in mice

The gastroprotective effects of 70% acetone extracts of Quercus suber and Quercus coccifera leaves and of tannins (pedunculagin, castalagin, phillyraeoidin A, and acutissimin B) purified from these extracts were examined in the mouse using the ethanol-induced gastric ulcer model. Both extracts (25, 50, and 100 mg/kg), given orally, prevented the formation of ethanol-induced lesions in the stomach. The percent protection varied between 68 and 91%. Purified tannins (50 mg/kg) were also effective in protecting the stomach against ethanol, and the percent protection varied from 66 to 83%. Castalagin was the most potent. Both extracts and all of the tannins tested (10, 25, and 50 microg/mL) strongly inhibited (55-65%) the lipid peroxidation of rabbit brain homogenate. These results suggest that the gastroprotective effects of extracts of Q. suber and Q. coccifera leaves and the purified tannins in this experimental model are related to their anti-lipoperoxidant properties.     

Selection and characterization of Phytophthora parasitica mutants with ultraviolet-induced resistance to dimethomorph or metalaxyl

Mutants of Phytophthora parasitica Dast. more or less resistant to dimethomorph or metalaxyl were obtained by treating mycelium with ultraviolet radiation. Some metalaxyl-resistant mutants exhibited levels of resistance (i.e. the ratio between the EC₅₀ values for the mutant and the wild-type strain) greater than 100, but those observed in the dimethomorph-resistant mutants never exceeded 25. Most mutants retained their resistance after sub-culturing on unamended agar medium. Single zoospore clones derived from a metalaxyl-resistant and a dimethomorph-resistant mutant, selected as amongst the most resistant, had levels of resistance similar to those of the parental strains. The metalaxyl-resistant mutants were also resistant to the related phenylamide fungicides, furalaxyl and benalaxyl, but remained sensitive to dimethomorph. The dimethomorph-resistant mutants were not resistant to phenylamide fungicides. The pathogenicity of some metalaxyl- or dimethomorph-resistant mutants on tobacco leaves was similar to that of the wild-type strains.     

Emergence de Ceratitis capitata (Diptera: Tephritidae) sur culture protégée de piment (Solanaceae) en zone subsaharienne (Algérie)

In Algeria, the Mediterranean fruit fly has long been associated with fruit production in coastal regions with a temperate climate. But with climate change, especially in autumn and spring, this fly has spread and attacks other host plants. The medfly appeared in the sub-Saharan area of Souf region (Algeria) on chilli pepper (Capsicum annuum) under protected crops and causes significant damage.     

Quantitative and qualitative analysis of alkaloids composition in the seeds of a white lupin (<Emphasis Type="Italic">Lupinus albus</Emphasis> L.) collection

White lupin (Lupinus albus L.) has unexploited potential as a crop plant due to its high seed yield as well as protein and oil content in seeds. Well-characterized collections of gene resources are very important for breeding as a source of genetic variation. This paper presents the results of analyses for total content and qualitative composition of alkaloids in seeds of 367 L. albus accessions from the Polish Genebank. Accessions were divided into four classes of origin: wild collected material, land races, breeding lines, and cultivars. Apart from the expected broad variation as well as strong differentiation in the alkaloid content, a clear influence of domestication was observed. This was shown as an apparent decrease in the alkaloid content in breeding lines and cultivars classes. The total alkaloid content varies from 0.02 to 12.73% of the seed dry weight. Six major alkaloids (abundance >1%) were revealed: lupanine (28.22–94.49%, mean 76.06% in total content), 13-hydroxylupanine (0.10–32.78%, mean 8.23%), multiflorine (0.00–21.67%, mean 5.52%), albine (0.00–18.55%, mean 4.48%), angustifoline (0.24–12.14%, mean 2.07%), 11,12-seco-12,13-didehydromultiflorine (0.00–12.28%, mean 1.74%). Owing to its abundance, lupanine was found to be the most closely correlated to the total alkaloid content.     

Regional and maturational effects on essential oils yields and composition of coriander (Coriandrum sativum L.) fruits

The composition of volatile components of the essential oils extracted from fruits of coriander (Coriandrum sativum L.) growing in two different Tunisian regions in both Menzel Temime and Borj El Ifaa was studied by GC and GC–MS. The highest oil yields were observed at final stages of maturity: 0.324 ± 0.09% and 0.327 ± 0.08%, in Menzel Temime and Borj El Ifaa, respectively. Essential oil yields were highly (P < 0.001) affected by the growing region, stages of maturity and their interaction. Essential oil composition changed significantly (P < 0.05) among the different stages of maturity and growing region. Linalool and geranyl acetate were the main compounds at full fruit maturity in the two studied regions. Growing region, stages of maturity and their interaction had a strong effect (P < 0.001) on 35 compounds. α-Pinene, sabinene, limonene, γ-terpinene, cis-dihydrocarvone and geranial were insensible to the regional factor.