Rajashekar Y, Ravindra K V, Bakthavatsalam N
National Bureau of Agriculturally Important Insects, P. Bag No: 2491, H.A. Farm Post, Bellary Road, Bangalore, 560 024 Karnataka India.
J Food Sci Technol. 2014 Nov;51(11):3494-9. doi: 10.1007/s13197-012-0884-8. Epub 2012 Oct 30.
Insects cause extensive damage to stored grains and their value added products. Among the stored grain pests Sitophilus oryzae (L.) Callosobruchus chinensis (Fab.) and Tribolium castaneum (Herbst.) are considered as destructive pests in India. Plants may provide alternatives to currently used insect control agents as they constitute rich source in bioactive molecules. Lantana camara, an erect shrub, which grows widely in the tropics, exhibits insecticidal activity against several insects. The methanol extract from leaves of L. camara has fumigant and contact toxicity against S. oryzae, C. chinesis and T. castaneum. In fumigant assays, The LC50 for S. oryzae was 128 μl/L(1), C. chinensis 130.3 μl/L(1), and T. castaneum 178.7 μl/L(1). The LD50 values for S. oryzae C. chinensis and T. castaneum in contact toxicity were 0.158, 0.140 and 0.208 mg/cm(2), respectively. For grain treatment, a concentration of 500 mg/L(1) and 7 days exposure were needed to obtain 90 - 100 % population extinction in all three insects. Probit analysis showed that C. chinensis were more susceptible than S. oryzae and T. castaneum. Gaschromatography-Mass Spectrometer (GCMS) studies for extracts indicated the presence of potent fumigant molecules in L. camara. The prospect of utilizing L. camara as potent fumigant insecticide is discussed.
昆虫对储存谷物及其增值产品造成广泛损害。在储存谷物害虫中，米象（Sitophilus oryzae (L.)）、绿豆象（Callosobruchus chinensis (Fab.)）和赤拟谷盗（Tribolium castaneum (Herbst.)）在印度被视为毁灭性害虫。植物可能为当前使用的昆虫控制剂提供替代方案，因为它们含有丰富的生物活性分子来源。马缨丹（Lantana camara）是一种直立灌木，在热带地区广泛生长，对多种昆虫具有杀虫活性。马缨丹叶片的甲醇提取物对米象、绿豆象和赤拟谷盗具有熏蒸和触杀毒性。在熏蒸试验中，米象的LC50为128 μl/L(1)，绿豆象为130.3 μl/L(1)，赤拟谷盗为178.7 μl/L(1)。米象、绿豆象和赤拟谷盗在触杀毒性方面的LD50值分别为0.158、0.140和0.208 mg/cm(2)。对于谷物处理，需要500 mg/L(1)的浓度和7天的暴露时间才能使所有三种昆虫的种群灭绝率达到90 - 100%。概率分析表明，绿豆象比米象和赤拟谷盗更敏感。提取物的气相色谱 - 质谱（GCMS）研究表明马缨丹中存在强效熏蒸分子。本文讨论了将马缨丹用作强效熏蒸杀虫剂的前景。
