Biochemical and histological alterations of cellular metabolism from jerboa (Jaculus orientalis) by 2,4-dichlorophenoxyacetic acid: Effects on d-3-hydroxybutyrate dehydrogenase

2,4-Dichlorophenoxyacetic acid (2,4D) is one of the widely used herbicide of the phenoxy family with possible startling number of adverse effects on species other than the weeds which is designed to kill. The effects of 2,4D were investigated in jerboa (Jaculus orientalis), a wild animal of subdesert highlands. The jerboas have been daily treated intraperitonally with 2,4D 3 mg/kg body weight for 4 weeks. Plasmatic markers, and antioxidants defences systems were assessed and histological alterations were evaluated. The in vivo and in vitro effects of 2,4D on the mitochondrial d-3-hydroxybutyrate dehydrogenase (BDH) were also determined. Our results showed a strong decrease of triglycerides level and HDL cholesterol and an increase in GOT level and LDL cholesterol. The microscopic evaluation showed that 2,4D induced necrosis of seminiferous tubules cells in testis, hyperplasia of hepatocytes in liver and presence of multinucleated giant cells in brain. The results show also an inhibitory effect on BDH in terms of activity and kinetic parameters. All of these results show that 2,4D induces toxicity which affects energy metabolism, morphological perturbation and oxidative stress.     

Insecticidal action of phytohemagglutinin (PHA) against the grain aphid, Sitobion avenae

The effects of phytohemagglutinin (PHA) on development, fecundity, and mortality of the grain aphid, Sitobion avenae (Fabricius), were determined. Also determined were the effects of PHA on the activity of gut enzymes involved in sugar and phosphorus metabolism (α- and β-glucosidase and alkaline and acid phosphatase) and on the feeding behavior of adult apterae.When added to a liquid diet, PHA increased the pre-reproductive period, decreased fecundity, and increased mortality of S. avenae. PHA also increased the developmental time and reduced the intrinsic rate of natural increase. The aphids fed on sucrose-agarose gels with higher concentrations of PHA lectin exhibited no phloem-feeding behavior. The number of the gel penetrations was reduced and duration of the pathways was increased by higher concentrations of PHA. In addition, activities of α-glucosidase and alkaline phosphatase in homogenates of adult aphids were reduced. The results indicate that PHA has potential in a biotechnological approach to insect management.