Hexane extracts from Tephrosia vogelii Hook. f. protect stored maize against the weevil Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)

Abstract

Powdered dried leaves of Tephrosia vogelii (Hook) (Leguminosae: Papilionoideae) were extracted using hexane, acetone, and ethanol. The extracts were tested for their ability to protect stored maize from damage by Sitophilus zeamais Motschulsky, the major maize weevil in Africa. The acetone and ethanol extracts were ineffective, but the hexane extract had a relatively high efficacy, producing within 7 days a slow reduction in adult survival, reduced numbers of eggs laid and reduced numbers of F1 progeny, resulting in seed damage averaging 8.8% compared with 98.6% in the untreated control after one generation. This hexane extract provided control of S. zeamais at a higher level compared with neem (the botanical control) but at a lower level compared with pirimiphos-methyl (the synthetic control). These findings are discussed in the context of T. vogelii containing rotenoids.

Effect of Hexaflumuron on Gustation and Reproduction of Adult Boll Weevil

“…In the present study, the extract from P. prunifolia leaves mixed with corn grains presented toxicity to S. zeamais adults in a shorter time (LT 50 and LT 90 ), similar to the hexanic CH 3 (CH 2 ) 4 CH 3 extract from T. vogelii mixed with food, which reduced the population of S. zeamais by 50% after 5 days of application (Koona et al 2007). Medicinal herbs have shown anti-feeding and insecticidal activity against stored grain pests (Liu et al 2007).…”

Brown Stink Bug Mortality by Seed Extracts of Tephrosia Vogelii Containing Deguelin and Tephrosin

“…Botanical insecticides also may present a satisfactory cost benefit relationship when compared to pesticides 5 . In the past, rotenone was the primary agent used to control insects, and its insecticidal and repellent activities have been most studied in relation to stored-grain insects 6,7 . The genera that had most commonly used for extraction is Derris Lour.…”

“…Technol. v.61: e18180028 2018 H4); 6.52 (d 10.0 Hz, H4'); 6.49 (s, H1) and 7.65 (d 8.8 Hz, H11) -13 C 108.5 (1a); 111.7 (1); 148.3 (2); 148.3 or 151.0 (3); 101,0 (4); 148.3 or 150.9 (4a); 66.8(6); 75.9 (6a); 156.5 (7a); 109.0 (8); 160.6 (9); 109.3 (10); 128.4 (11); 111.0 (11a); 191.3(12); 67.4 (12a); 115.3 (4'); 128.7 (5'); 77.9 (6'); 26.1/26.4 (7'/8') and 55.7/56.2 (OCH3)2]. Rotenoids in minority are shown only in mass spectra of the column fractions corresponding to chromatogram peaks.…”