The essential oil (EO) from the leaves of Tithonia diversifolia (Hemsl.) A. Grey was investigated to determine chemical composition and fumigant toxicity against two major stored grain pests rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae) and red flour beetle, Tribolium castaneum (Herbst.) (Coleoptera: Tenebrionidae). A total of 78 compounds were identified by GC-MS of which α-Pinene (63.62%), Bicyclo [3.1.0] hexane, 4-methylene-1-(1-methyl ethyl)- (14.68%) and 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl-, (E)- (2.34%) were most abundant. EO from leaves of T. diversifolia showed strong fumigant activity against S. oryzae adults with LC₅₀ values of 95.12, 77.00 and 74.68 µL/L air after 24, 48 and 72 h of exposure whereas for T. castaneum the LC₅₀ values were 102.67, 98.12 and 81.54 µL/L air, respectively. Mortality rates increased with increasing exposure periods and increasing concentration. These naturally occurring materials derived from EO of T. diversifolia could be used to manage the populations of S. oryzae and T. castaneum. It was found that the EO’s of T. diversifolia is very effective as a fumigant against stored grain insect pests and can also be used as an alternative to the synthetic fumigants.

研究了Tithonia diversifolia（Hemsl。）A. Gray的叶子中的精油（EO），以确定其对两种主要储存的谷类害虫稻象鼻虫（Sitophilus oryzae（L。）（鞘翅目：Curculionidae）和红色）的化学成分和熏蒸毒性。面粉甲虫，Tribolium castaneum（Herbst。）（鞘翅目：天蛾科）。通过GC-MS鉴定出总共78种化合物，其中α - ene烯（63.62％），双环[3.1.0]己烷，4-亚甲基-1-（1-甲基乙基）-（14.68％）和1,6 ，10-十二碳三烯-3-醇，3,7,11-三甲基-，（E）-（2.34％）含量最高。T. diversifolia叶片的EO对LC _50的米曲霉成虫表现出较强的熏蒸活性。的95.12，77.00和74.68的值μL/ L空气后曝光的24，48和72小时，而对于赤拟谷盗的LC _50个值分别为102.67，98.12和81.54μL/ L的空气，分别。死亡率随着接触时间的延长和注意力的增加而增加。从EO衍生的这些天然存在的材料T. diversifolia可以用来管理的种群米象和赤拟谷盗。结果发现，该EO的的T. diversifolia是作为对抗储粮害虫熏蒸剂非常有效，也可以使用以替代合成的熏蒸剂。