Laboratory experiments evaluated the latent effects of lufenuron and rice bran extract on the newly hatched nymphs of Schistocerca gregaria produced from females who were treated as fifth nymphal instar with LC50 of each lufenuron and rice bran extract. Semithin sections of the newly hatchling showed great histological malformations in the structure of the brain, compound eyes, midgut, and hind leg muscles compared with control, these organs lost their normal structures, shapes, and functions. The tested compounds had serious extended histopathological effects, so they can be used to control S. gregaria as safe alternative agents to toxic synthetic pesticides.

No abstract

Entomopathogenic nematode (EPNs) Steinernema carpocapsae was tested against the Locusta migratoria L., 5 th instar nymphs under laboratory conditions. The mortality of nymphs maintained on three concentrations (10, 20 and 40 IJs/g) nematode-inoculated sand was particularly high. Nematode was effective, causing 100% mortality of fifth nymphal instars after third days of treatment. The impact of S. carpocapsae parasitation on L. migratoria immune defense was closely examined, after both 24-48h post treatment with LC 50 of nematode the activities of phenoloxidase (PO), peroxidase (POD), α and β estrases (ESTs) and glutathione-S-transferase (GSTs) enzymes of the whole body were estimated. S. carpocapsae affect locust causing high mortality rate, which significantly increased in concentrations and time dependent manner, this effect might be because of enzyme system distraction. These results demonstrated that, the entomopathogenic nematode broke host immunity, by the changes of enzymes activities; that provide an overview about the efficiency of nematode and its effects on L. migratoria.

The aim of this study was to evaluate the activity of some oxidative enzymes in three genotypes of maize namely (Baghdad, 5018, Sara) under three sowing dates: (26July, 4August and 12August) and denote (D1, D2 and D3). A field experiment was conducted at field of College of Agricultural Engineering Sciences, University of Baghdad/Al- Jadriya for the fall season 2021- 2022, factorial experiment was conducted using randomized blocks (RCBD) with three replicates. Significant differences were found among genotypes for the number of grains in the row, and the number of kernels in the ear. The results showed that superiority of the genotype (Baghdad) in the characteristic of Tasseling and Silking flowering 50%, plant yield with averages of 58.89d, 62.89d and 164.6g, respectively. While the genotype (Sara) was superior to the weight of 100 kernels, with an average weight of 27.34g. Genotype (5018) gave the highest value for Catalase (CAT) and Peroxidase (POD) enzyme, which was 2.16 u/mg and 0.51 u/mg, respectively, while genotype (Sara) gave the highest value for Superoxide dismutases (SODs), which was 50.15u/mg The (D1) showed an increase in most of the traits averages, especially (50% tasseling which gave 65.00d),(50% Silking which gave 68.00d),(weight of 100 grains which reached 26.91g) and (POD enzyme 0.56 u/mg). The (D3) gave the highest value for plant yield which was 162.1g, CAT enzyme 2.54u/mg and SOD enzyme 57.34u/mg.