Impact of Spodoptera littoralis (Boisd.) and Agrotis ipsilon (Hufn.) larval frass on oviposition of conspecific insects

• Published in: Archiv für Phytopathologie und Pflanzenschutz Vol. 46; no. 5; pp. 575 - 592
• Main Authors: Ahmed, A.A.I., Hashem, M.Y., Adel, Manal M., Mohamed, S.M., Khalil, S.H. Shimaa
• Format: Journal Article
• Language: English
• Published: Abingdon Routledge 01.03.2013; Taylor & Francis Ltd
• Subjects: Agrotis ipsilon; Conspecifics; Cotton; Deterrents; Diets; Eggs; Fatty acids; Feeding; Food; Food sources; Gas chromatography; gas chromatography-mass spectrometry; Herbivores; larval frass; Leaves; Mass spectrometry; Mass spectroscopy; Oil; Oleic acid; Oviposition; oviposition deterrent; Palmitic acid; Plant protection; Spodoptera littoralis
• ISSN: 0323-5408; 1477-2906
• DOI: 10.1080/03235408.2012.749691

Ethanolic extracts of larval frass of the cotton leaf worm and the black cutworm were prepared and tested to deter the eggs lay of the adults of the same insects. Two different types of food were used for larval feeding. Extracts fractions were identified using gas chromatography-mass spectrometry analysis. High concentrations were more deterrent to oviposition than low. Extracted frass of fed larvae on semi-artificial diet was more effective than others fed on natural host. Sensitivity of the black cutworm adult females to the cotton leaf worm frass extract was clearly observed at high tested concentration of L 1-3 and L 4 frass extracts which resulted completely oviposition deterrent. Several fatty acids were identified qualitatively and quantitatively in frass extracts of different larval instars of both target insects. Type and quantity of fatty acid depends mainly on larval food source and larval instar, except palmitic acid which recorded at all larval instars and food sources. Oleic acid and ethyl 9-hexadecaenoic acid were found when semi-artificial diet used as a food source while myrisitic acid was observed only in extracted frass of fed larvae on castor oil leaves.