Protein-enriched pea flour extract protects stored milled rice against the rice weevil, Sitophilus oryzae

Malaa

2007

Entomological Science

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.

Section: Discussionmentioning

confidence: 91%

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

Malaa

2007

Entomological Science

The Scientific World Journal

“…Acetone seed extract of Aphanamixis polystachya showed 100% repellent effects on red flour beetles [32]. Pretheep-Kumar et al [33] found a maximum of 91.2% of repellency with an extract of protein enriched bean flour on weevils, S. oryzae, after 48 h of the test period. e high insect repellent results seen in this study are also supported by Boateng and Kusi [34] who showed that J. curcas seed extracts could repel up to 95% of the C. maculatus and D. basalis.…”

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Repellent Effects of Selected Organic Leaf Extracts of Tithonia diversifolia (Hemsl.) A. Gray and Vernonia lasiopus (O. Hoffman) against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)

Gitahi

Ngugi

Mburu

et al. 2021

Introduction. Sitophilus zeamais infestation is among the major setbacks to sustainable maize farming and availability. It causes an estimated annual loss of 5–10% and 20–30% of the total maize grains loss in the temperate and tropical zones, respectively. Although synthetic pesticides are quick and effective in managing crop pests, their overuse and misuse is discouraged due to their detrimental effects on human and environment. Natural pesticidal products that are extracted from plants are particularly gaining importance as an alternative to synthetic pesticides. They are available, easily biodegraded and have low toxicity to nontarget organisms. Most botanical pesticides act on insects by repelling them away from the crops in the field or in the stores. Therefore, this study aimed to determine repellency potential of organic leaf extracts of Tithonia diversifolia and Vernonia lasiopus on S. zeamais. Materials and methods. The phytochemical profile of T. diversifolia and V. lasiopus was determined using GC-MS. Laboratory-based experiments were carried out using area preference method to assess the efficacy of the extracts against weevils for a test period of 5 h. Six groups of experiments were set up with ten S. zeamais in each test: positive control (Actellic), negative control (solvent only), and four different experimental extract concentrations (25, 50, 75, and 100%). Results. The results indicated that T. diversifolia and V. lasiopus leaf extracts possess potent repellency effect on weevils. All the extracts simply discouraged S. zeamais from the treated areas recording significantly good levels of repellent activities between 26 and 96%. Furthermore, the GC-MS analysis manifested the presence of bioactive compound in the extracts which are associated with the repellency effects. Conclusion. The study scientifically confirms the traditional use of the T. diversifolia and V. lasiopus and provides important platform for further study on the extracts as bioresource of botanical repellent.

“…Agron., 14 (4): 298-303, 2015 have reported that legume seeds contain a wide range of allelochemicals with toxic and deterrent effects against insect pests. The insecticide effect of pea flour on rice weevil (Sitophilus oryzae L.) have received the most attention (Hou and Fields, 2003;Pretheep-Kumar et al, 2004;Fields, 2006). Pea protein is repellent to several stored-product insects (Fields et al, 2001;Kumar et al, 2004) and toxic (Pretheep-Kumar et al, 2004).…”

Section: Introductionmentioning

confidence: 99%

“…The insecticide effect of pea flour on rice weevil (Sitophilus oryzae L.) have received the most attention (Hou and Fields, 2003;Pretheep-Kumar et al, 2004;Fields, 2006). Pea protein is repellent to several stored-product insects (Fields et al, 2001;Kumar et al, 2004) and toxic (Pretheep-Kumar et al, 2004). This toxicity is primarily correlated with the biological activity of a major albumin isolated from pea grains, pea albumin1 subunit b (PA1b) (Gressent et al, 2003).…”

Section: Introductionmentioning

confidence: 99%

Insecticidal Activity of Pea Albumin 1b Homologous against Granary Weevil (Sitophilus granarius L.)

Mebarkia¹,

Abdi²,

Rahmani³

et al. 2015

J. of Agronomy

The aim of this study was to evaluate the toxicity of pea albumin 1 subunit b (PA1b) homologous against granary weevil (Sitophilus granarius L.). Adults of less than 5 days were maintained at 27±0.2°C and 70±5% relative humidity, on bread wheat (Triticum aestivum L. subsp. Aestivum) flour dumplings (control) and on pea flour, chickpea, bean, lentil, broad bean (toxic) during 15 days. The concentrations of used pea flour were 10, 20, 40, 60 and 80%. On PA1b reference: Pea/wheat with 80% pea flour, we have observed on the 3rd day, a mortality rate over 10%. From 7 days there were no survivors. For concentrations of 40 and 60%, the mortality rate was 73 and 93%, respectively; but at 10 and 20% of pea, the rate was low not exceeding the 20% threshold. A significantly positive correlation (R 2 = 0.91) was observed between the concentration of pea flour extract and the mortality rate of Sitophilus granarius L. The linear regression of semi-logarithmic curve is highly significant (p = 0.012, <0.05) and allow to determine the LD 50 of which is 25.63±3.26% or 64.075±8.14 mg. At the maximum concentration of 80% on lentil, bean and broad bean, there was a total mortality of the insect at 7 days; others are less toxic such as pea with 30% and chickpea, whose mortality rate does not exceed the 23% threshold. Furthermore, complete mortality of the insect was observed after 14 days in all grain legumes.