This work was conducted to assess the anatomical features of Pistacia atlantica Desf. under Mediterranean semi-arid climate conditions. In this study, phytoecological approach was used at different observation scales ...This work was conducted to assess the anatomical features of Pistacia atlantica Desf. under Mediterranean semi-arid climate conditions. In this study, phytoecological approach was used at different observation scales including the large ecological scale. 11 samples of P. atlantica species were randomly selected in order to study the anatomy of leaves and branches. The results show that leaves have palisade parenchyma occupying almost the entire mesophyll, measuring 100 to 170 μm. While in branches, the only pith occupies 38% followed by the xylem (24%), relative to the rest of the tissue (epidermis, periderm, collenchyma, pericyclic fiber, secretory duct and phloem). The current results suggest that P. atlantica species has xeromorphic anatomical characters, giving it great ecological plasticity in an arid environment. Moreover, this study shows that the human activities are causing local extinction of this rare species in Algeria.展开更多
The olive fruit fly Bactrocera oleae is a major olive pest in Algeriaand other Mediterranean countries. Its attacks, in some cases, seriously compromised production. Bacillus thuringiensis is a spore-forming soil bact...The olive fruit fly Bactrocera oleae is a major olive pest in Algeriaand other Mediterranean countries. Its attacks, in some cases, seriously compromised production. Bacillus thuringiensis is a spore-forming soil bacterium which produces a protein crystal toxic to some insects. The objective of this study was to search for isolates toxic to larvae and adults of B. oleae. Four doses test were performed on neonate larvae, second instar larvae and third instar larvae. Seven Bt strains examined, showed highest toxicity levels against adults. 86% mortality was observed against neonate larvae after 7 days of application by Bt toxin isolate. The mortality of the second instar larvae was 65% mortality at dose of 108 UFC/mL. The third instar larvae was very susceptible to Bt strain with 70% of mortality. This study demonstrated that some local Algerian B. thuringiensis isolates exhibit toxic potential that could be used to control B. oleae.展开更多
文摘This work was conducted to assess the anatomical features of Pistacia atlantica Desf. under Mediterranean semi-arid climate conditions. In this study, phytoecological approach was used at different observation scales including the large ecological scale. 11 samples of P. atlantica species were randomly selected in order to study the anatomy of leaves and branches. The results show that leaves have palisade parenchyma occupying almost the entire mesophyll, measuring 100 to 170 μm. While in branches, the only pith occupies 38% followed by the xylem (24%), relative to the rest of the tissue (epidermis, periderm, collenchyma, pericyclic fiber, secretory duct and phloem). The current results suggest that P. atlantica species has xeromorphic anatomical characters, giving it great ecological plasticity in an arid environment. Moreover, this study shows that the human activities are causing local extinction of this rare species in Algeria.
文摘The olive fruit fly Bactrocera oleae is a major olive pest in Algeriaand other Mediterranean countries. Its attacks, in some cases, seriously compromised production. Bacillus thuringiensis is a spore-forming soil bacterium which produces a protein crystal toxic to some insects. The objective of this study was to search for isolates toxic to larvae and adults of B. oleae. Four doses test were performed on neonate larvae, second instar larvae and third instar larvae. Seven Bt strains examined, showed highest toxicity levels against adults. 86% mortality was observed against neonate larvae after 7 days of application by Bt toxin isolate. The mortality of the second instar larvae was 65% mortality at dose of 108 UFC/mL. The third instar larvae was very susceptible to Bt strain with 70% of mortality. This study demonstrated that some local Algerian B. thuringiensis isolates exhibit toxic potential that could be used to control B. oleae.