{"title":"桉树精油对玉米象(Motschulsky, 1855)和棘皮虫(Say, 1831)的化学成分和杀虫潜力","authors":"Christine Betty Nagawa , Isaac Sebuyiira Kitiibwa , Simon Savio Kizito , Agatha Syofuna , Christine Mugumya Kyarimpa , Timothy Omara","doi":"10.1016/j.sajb.2025.02.002","DOIUrl":null,"url":null,"abstract":"<div><div>Coleopteran pest infestation is among the top causes of postharvest grain losses in East Africa. This study investigated the phytochemical composition and bioinsecticidal potential of essential oils (EOs) from fresh leaves of two <em>Eucalyptus</em> species (<em>E. camuldulensis</em> and <em>E. grandis</em>) grown in Arua and Kabarole Districts of Uganda on bean weevils (<em>Acanthoscelides obtectus</em>) and maize weevils (<em>Sitophilus zeamais</em>). Treatment with EO of the three-year-old <em>E. camuldulensis</em> from Arua showed the best insecticidal activity at 50 µL/mL against <em>S. zeamais</em> with 100 % mortality after 24 h. The best bioinsecticidal effect against <em>A. obtectus</em> (100 % mortality) was observed with EO of five-year-old <em>E. grandis</em> from Kabarole at 20 µL/mL. Gas chromatography/mass spectrometry analysis showed that cyclofenchene (6.61–51.69 %), trifluoroacetyl-α-terpineol (2.75–54.58 %) and 3-hexanone (9.85–35.98 %) were the major components in all the EOs. The high insecticidal activity of the EO of three-year-old <em>E. camuldulensis</em> from Arua against <em>S. zeamais</em> could be due to its high 3-hexanone (35.98 %), 1-hydroxy-1-methyl-2-oxoindane (19.21 %) and eucalyptol (9.96 %) contents. On the other hand, the highest insecticidal activity of EO of the five-year-old <em>E. grandis</em> leaves from Kabarole against <em>A. obtectus</em> may be associated with its components: 2-Bornanol (1.41 %) and 2,6-Dimethyl-1,3,5,7-octatetraene, E,E- (1.05 %). Our results suggest that the use of EOs from the <em>Eucalyptus</em> species is a promising alternative for integrated management of the storage pests. Oils from the three-year old <em>E. camuldulensis</em> and five-year-old <em>E. grandis</em> leaves could be adopted as an alternative nature-based solution for combating maize and bean weevils, respectively in stored food products.</div></div>","PeriodicalId":21919,"journal":{"name":"South African Journal of Botany","volume":"179 ","pages":"Pages 48-55"},"PeriodicalIF":2.7000,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Chemical composition and insecticidal potential of Eucalyptus essential oils against Sitophilus zeamais (Motschulsky, 1855) and Acanthoscelides obtectus (Say, 1831)\",\"authors\":\"Christine Betty Nagawa , Isaac Sebuyiira Kitiibwa , Simon Savio Kizito , Agatha Syofuna , Christine Mugumya Kyarimpa , Timothy Omara\",\"doi\":\"10.1016/j.sajb.2025.02.002\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Coleopteran pest infestation is among the top causes of postharvest grain losses in East Africa. This study investigated the phytochemical composition and bioinsecticidal potential of essential oils (EOs) from fresh leaves of two <em>Eucalyptus</em> species (<em>E. camuldulensis</em> and <em>E. grandis</em>) grown in Arua and Kabarole Districts of Uganda on bean weevils (<em>Acanthoscelides obtectus</em>) and maize weevils (<em>Sitophilus zeamais</em>). Treatment with EO of the three-year-old <em>E. camuldulensis</em> from Arua showed the best insecticidal activity at 50 µL/mL against <em>S. zeamais</em> with 100 % mortality after 24 h. The best bioinsecticidal effect against <em>A. obtectus</em> (100 % mortality) was observed with EO of five-year-old <em>E. grandis</em> from Kabarole at 20 µL/mL. Gas chromatography/mass spectrometry analysis showed that cyclofenchene (6.61–51.69 %), trifluoroacetyl-α-terpineol (2.75–54.58 %) and 3-hexanone (9.85–35.98 %) were the major components in all the EOs. The high insecticidal activity of the EO of three-year-old <em>E. camuldulensis</em> from Arua against <em>S. zeamais</em> could be due to its high 3-hexanone (35.98 %), 1-hydroxy-1-methyl-2-oxoindane (19.21 %) and eucalyptol (9.96 %) contents. On the other hand, the highest insecticidal activity of EO of the five-year-old <em>E. grandis</em> leaves from Kabarole against <em>A. obtectus</em> may be associated with its components: 2-Bornanol (1.41 %) and 2,6-Dimethyl-1,3,5,7-octatetraene, E,E- (1.05 %). Our results suggest that the use of EOs from the <em>Eucalyptus</em> species is a promising alternative for integrated management of the storage pests. Oils from the three-year old <em>E. camuldulensis</em> and five-year-old <em>E. grandis</em> leaves could be adopted as an alternative nature-based solution for combating maize and bean weevils, respectively in stored food products.</div></div>\",\"PeriodicalId\":21919,\"journal\":{\"name\":\"South African Journal of Botany\",\"volume\":\"179 \",\"pages\":\"Pages 48-55\"},\"PeriodicalIF\":2.7000,\"publicationDate\":\"2025-02-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"South African Journal of Botany\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0254629925000638\",\"RegionNum\":3,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"PLANT SCIENCES\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"South African Journal of Botany","FirstCategoryId":"99","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0254629925000638","RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PLANT SCIENCES","Score":null,"Total":0}
Chemical composition and insecticidal potential of Eucalyptus essential oils against Sitophilus zeamais (Motschulsky, 1855) and Acanthoscelides obtectus (Say, 1831)
Coleopteran pest infestation is among the top causes of postharvest grain losses in East Africa. This study investigated the phytochemical composition and bioinsecticidal potential of essential oils (EOs) from fresh leaves of two Eucalyptus species (E. camuldulensis and E. grandis) grown in Arua and Kabarole Districts of Uganda on bean weevils (Acanthoscelides obtectus) and maize weevils (Sitophilus zeamais). Treatment with EO of the three-year-old E. camuldulensis from Arua showed the best insecticidal activity at 50 µL/mL against S. zeamais with 100 % mortality after 24 h. The best bioinsecticidal effect against A. obtectus (100 % mortality) was observed with EO of five-year-old E. grandis from Kabarole at 20 µL/mL. Gas chromatography/mass spectrometry analysis showed that cyclofenchene (6.61–51.69 %), trifluoroacetyl-α-terpineol (2.75–54.58 %) and 3-hexanone (9.85–35.98 %) were the major components in all the EOs. The high insecticidal activity of the EO of three-year-old E. camuldulensis from Arua against S. zeamais could be due to its high 3-hexanone (35.98 %), 1-hydroxy-1-methyl-2-oxoindane (19.21 %) and eucalyptol (9.96 %) contents. On the other hand, the highest insecticidal activity of EO of the five-year-old E. grandis leaves from Kabarole against A. obtectus may be associated with its components: 2-Bornanol (1.41 %) and 2,6-Dimethyl-1,3,5,7-octatetraene, E,E- (1.05 %). Our results suggest that the use of EOs from the Eucalyptus species is a promising alternative for integrated management of the storage pests. Oils from the three-year old E. camuldulensis and five-year-old E. grandis leaves could be adopted as an alternative nature-based solution for combating maize and bean weevils, respectively in stored food products.
期刊介绍:
The South African Journal of Botany publishes original papers that deal with the classification, biodiversity, morphology, physiology, molecular biology, ecology, biotechnology, ethnobotany and other botanically related aspects of species that are of importance to southern Africa. Manuscripts dealing with significant new findings on other species of the world and general botanical principles will also be considered and are encouraged.