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| C. Ciências Biológicas - 3. Bioquímica - 6. Bioquímica | ||
| EFFECTS OF THE GLUCOSE/MANNOSE-BINDING LECTIN FROM Canavalia brasiliensis SEEDS ON THE DEVELOPMENT OF Callosobruchus maculatus (COLEOPTERA: BRUCHIDAE). | ||
| José Delano M Barreto-Filho 1 (jdelano81@uol.com.br), Cleverson Diniz Teixeira de Freitas 1, Emanoela Lima Soares 1, Diego Pereira de Souza 1 e Márcio Viana Ramos 1 | ||
| (1. Depto. De Bioquímica e Biologia Molecular, Universidade Federal do Ceará - UFC) | ||
| INTRODUÇÃO:
Plant seeds contribute significantly to human and animal diets. Among them, cereal and legume seeds are important source of proteins. Cowpea (Vigna unguiculata) is a legume cultivated in most tropical regions of the world and it represents the most important source of proteins and carbohydrates for many people in undeveloped countries. One of the most important insect pests of the cowpea is the bruchid weevil Callochobruchus maculatus (F.), which attacks the seeds during storage, severely affecting the quality and storability of the produce. Lectins are proteins commonly found in plant seeds and there is increasing evidence that they can protect seeds against insects and other herbivores. |
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| METODOLOGIA:
The present work aimed to examine the effects of ConBr, the legume lectin purified from Canavalia brasiliensis on C. maculatus development. For this, artificial seeds (480 mg) were made from finely ground commercial cowpea seeds containing native or denatured ConBr at concentrations of 0.2, 0.5, 1 and 2 % (w/w). The seeds were infested with insects for three days. After oviposition, the number eggs per seed were reduced to five, and an incubation period of 16 days was followed at 27 °C and 70-75 % relative humidity. At this time, the seeds were opened and the number and weight of larvae were determined. Development time until insect emergence and the percentage of emergency were also examined. Control artificial seeds were made with commercial cowpea meal containing no added lectin and other control group was with denatured lectin prepared after boiling a solution of native lectin (8 mg/mL) for 30 minutes followed by lyophilization. Each treatment was replicated four times for such concentrations with 16 seeds each. |
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| RESULTADOS:
The mortality and weight of cowpea weevil larvae feeding on control seeds were 19.37 % and 6.13 mg, respectively, while the seeds containing native and denatured ConBr 2% were 22.83 %, 4.17 mg and 31.96 %, 4.52 mg, respectively. The time of development and percentage of emergency were 26.5 days and 59.9 % for seeds control no lectin and 29.8 days, 41.31 % and 28.53 days, 63 % for seeds containing native and denatured ConBr 2%, respectively. |
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| CONCLUSÕES:
Among the parameters analyzed, the lectin from C. brasiliensis seeds showed a weak inhibitory effect on the development of insect C. Maculatus. The most prominent difference was the larval weight that decreased in larvae feeding ConBr 2% comparing to the control growing without the lectin. All the data will be further statistically analyzed. |
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| Instituição de fomento: CNPq/PADCT, FUNCAP, and IFS. | ||
| Trabalho de Iniciação Científica | ||
| Palavras-chave: plant lectins; Callosobruchus maculatus; Canavalia brasiliensis . | ||
| Anais da 57ª Reunião Anual da SBPC - Fortaleza, CE - Julho/2005 |