Insecticidal action of Bauhinia monandra leaf lectin (BmoLL) against Anagasta kuehniella (Lepidoptera: Pyralidae), Zabrotes subfasciatus and Callosobruchus maculatus (Coleoptera: Bruchidae)

• Published in: Comparative biochemistry and physiology. Part A, Molecular & integrative physiology Vol. 146; no. 4; pp. 486 - 498
• Main Authors: Macedo, Maria Lígia Rodrigues, Freire, Maria das Graças Machado, da Silva, Maria Barbosa Reis, Coelho, Luana Cassandra Breitenbach Barroso
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.04.2007
• Subjects: Anagasta kuehniella; Animals; Bauhinia - chemistry; Bauhinia monandra; Biological Assay; Bruchidae; Callosobruchus maculatus; Chromatography, Affinity; Coleoptera; Coleoptera - drug effects; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical - methods; Insect Proteins - metabolism; Insect resistance; Insecticides - pharmacology; Larva - drug effects; Larva - physiology; Leaf lectin; Lepidoptera; Lepidoptera - drug effects; Lethal Dose 50; Papain - metabolism; Pepsin A - metabolism; Plant Leaves - chemistry; Plant Lectins - metabolism; Plant Lectins - pharmacology; Pyralidae; Trypsin - metabolism; Zabrotes subfasciatus; Zabrotes subfasciatus; Leaf lectin; Coleoptera; Insect resistance; Lepidoptera; Bauhinia monandra; Callosobruchus maculatus; Anagasta kuehniella
• ISSN: 1095-6433; 1531-4332
• DOI: 10.1016/j.cbpa.2006.01.020

Bruchid beetle larvae cause major losses in grain legume crops throughout the world. Some bruchid species, such as the cowpea weevil ( Callosobruchus maculatus) and the Mexican bean weevil ( Zabrotes subfasciatus), are pests that damage stored seeds. The Mediterranean flour moth ( Anagasta kuehniella) is of major economic importance as a flour and grain feeder; it is often a severe pest in flour mills. Plant lectins have been implicated as antibiosis factors against insects. Bauhinia monandra leaf lectin (BmoLL) was tested for anti-insect activity against C. maculatus, Z. subfasciatus and A. kuehniella larvae. BmoLL produced ca. 50% mortality to Z. subfaciatus and C. maculatus when incorporated into an artificial diet at a level of 0.5% and 0.3% (w/w), respectively. BmooLL up to 1% did not significantly decrease the survival of A. kuehniella larvae, but produced a decrease of 40% in weight. Affinity chromatography showed that BmoLL bound to midgut proteins of the insect C. maculatus. 33 kDa subunit BmoLL was not digested by midgut preparations of these bruchids. BmoLL-fed C. maculatus larvae increased the digestion of potato starch by 25% compared with the control. The transformation of the genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops.