The aim of this study was to determine the effect of Pandanus (Pandanus amaryllifolius 20 Roxb.) and Neem (Azadirachta indica) leaves powder on the repellency, mortality, and weight loss 21 of grains due to Sitophilus oryzae. The methodes of this study used a completely randomized design 22 (CRD) with 7 treatments and 4 replications. The results of this study indicate that the best treat- 23 ment in terms of causing repellency was the treatment of 10 grams of pandanus with a percentage 24 of 87.5%, while the best treatment in terms of causing pest mortality and was also able to reduce 25 the risk of rice weight loss due to Sitophilus oryzae was treatment 10 gram of neem with a mortality 26 percentage of 76.25% and weight loss of rice 3.14%. This research showed that neem leaf com- 27 pounds are better in terms of causing mortality, while Pandanus compounds are better in terms of 28 causing mortality of Sitophilus oryzae.

COX II containing a dual core CuA active site is one of the three core subunits of mitochondrial Cco, which plays a significant role in the physiological process. In this report, the full-length cDNA of COXⅡ gene was cloned from Sitophilus zeamais, which had an ORF of 684 bp encoding 227 amino acids residues. The predicted COXⅡ protein had a molecular mass of 26.2 kDa with pI value of 6.37, and multiple sequence alignment and phylogenetic analysis indicated that Sitophilus zeamais COXⅡ had high sequence identity 78.51% with the COXⅡ of other insect species, especially similarity to sitophilus oryzae. This gene was subcloned into the prokaryotic expression vector pET-32a, and induced by IPTG in E.coli Transetta (DE3) expression system. Finally the COXⅡ with 6-His tag was purified using affinity chromatography with Ni²⁺-NTA agarose. WB showed the recombinant COXⅡ was about 44 kD, and the concentration of fusion protein was 50μg/mL. UV-spectrophotometer and infrared spectrometer analysis showed that recombinant COXⅡ could catalyze the oxidation of substrate Cytc, and influenced by AITC. It was found that AITC could form a hydrophobic region with COXⅡ protein via molecular docking, besides, a sulfur atom of AITC structure could form a length of 2.9 Å hydrogen bond with Leu-31. These results will provide valuable information for elucidating the role of COXⅡ in Sitophilus zeamais responses to AITC, meanwhile, it will helpful to carry out a point mutation in AITC binding sites for the future research.

The objective of this study was to compare the effect of different botanical powders and synthetic chemical in controlling Sitophilus zeamais in stored maize. A laboratory experiment was done to assess three botanicals, Zingiber officinale, Moringa oleifera, Xylopia aethiopica, in controlling the S. zeamais. The results of this study demonstrated the active potentials of these plant products as plant-derived insecticides against maize weevil. The synthetic chemical used showed both higher weevil mortality and higher grain loss than the botanicals (P< 0.05). The Botanicals also showed significance difference in the mortality rate (P < 0.05) as Z. officinale recorded the highest mortality rate (5.66%) while X. aethiopica recorded the lowest mortality rate (3.66%). The control attained the highest grain damage (7.33%) while amongst the botanicals, the highest was found in Z. officinale (7.33%) and lowest was on M. oliefera (5.33%). The exit holes made by the weevils at the end of the experiment were highest (2.66) in M. oliefera whereas lowest was recorded on X. aethiopica (1.00). Z. officinale, X. aethiopica and M. oleifera were efficacious against S. zeamais instead of synthetic chemical insecticides that have environmental health hazards and they can be used in integrated pest management by farmers and foods merchants. Therefore, since these botanicals have no any adverse effects on the seeds and safe to the environment, they are recommended for future usage in storage grains to control of S. zeamais.

Chemical variability in the components of T. vogelii essential oils from eastern Uganda was identified using principal component analysis (PCA) and Agglomerative hierarchical clustering (AHC). Based on the profiles of the compounds of farnesene family three chemotypes were found: farnesol (chemotype 1), springene (β- Springene and α-Springene) and the β-Farnesene were distinctive in chemotype 2 and a mixed variety of farnesol and the Springene. In the three cases, alkybenzenes; o-xylene, m-xylene and ethylbenzene were significant components in the oil. 1,4-dihydroxy-p-menth-2-ene, 5,9-undecadien-2-one, 6,10-dimethyl, and 3-cyclohexen-1-carboxaldehyde,3,4-dimethyl were other prominent constituents. The yields of the essential oils did not vary significantly however the chemical composition varied with harvesting time during the rainy and dry seasons. In choice repellency tests, chemotype 1 and chemotype 2 were more active against Sitophilus zeamais than mixed chemotype. Farnesol was found to be effective only at a higher concentration as a repellent against S. zeamais. However, further study that aims to optimize and standardize the varieties and harvesting period needed for recommendation to smallhold farmers.