SOUSA, Z. R. A.; http://lattes.cnpq.br/2798034194497997; SOUSA, Zilane Roberta Araújo.
Resumo:
The brazilian poultry system has been consolidating as the main national agrobusiness
activities in which has contributed at that agroindustrial economy segment of this
country. However, it stands out as a potential problem to reducing the poultry
productivity the pests, such as the beetle alphitobiusdiaperinus (little bell pepper).
against the need of finding alternative methods to the pesticides, of lower impact and
risk to the human health and to the environment. Botanical insecticides have benn
researched in many Latin American countries. Considering the good prospect for the
use of vegetable extracts such as an alternative to the family producers, this work has
had its main goal to evaluating the bioinsecticide action of mastruz
Chenopodiunambrosioides L., to controlling and repellency of the A. diaperinus, aiming
at its use in poultry. For efficiency evaluation, it has used concentration of the 2,5; 5,0;
7,5 and 100% + a witness (0%). The evaluations were carried out among 7, 14, 21 and
28 days after the bioassay installation. For data analysis was used polynomial regression
analyse, considering its level concentrations and the evaluation times. For each
concentration, it is made six repetitions. The studied variable was the numbers of dead
insects, it is also the cumulative average mortality evaluated. The efficiency of the
extract on adults of A. diaperinus was calculated by the ABBOTT method (1925) for all
evaluations. In the bioassay on repellency, it was simulated the condition of poultry,
using in each experimental unity rice straw and poultry feed. In each repetition, it has
introduced 30 adult insects of A. diaperinus, not sexed, with 24 hours of starvation. The
number of dead and alive insects in the treated receptors and not treated as well, and
they were evaluated 24 hours after the introduction of the insects. The repellency index
(IR) was calculated by the formula IR= 2G ( G + P) where G= % of the insects in the
treatment and P= % of the insects in the witnesses. The values of IR vary between 0-1,
indicating: IR=1, neutral product; IR>1 attractive product and IR<1, repellency product
(LIN et al., 1990 ) The values for the repellency index were submitted to polynominal
regression of analysis. It was also used the chi-square test (x) (p<0, 05) for comparison
between the average number of insects in each of the concentrations studied with the
number of the insects in the witness. According to the results, it is concluded that (1) the
mastruz extract has presented lower control efficiency over adults A. diaperinus; (2)
propably the filter paper failed to retain the mastruz extract, therefore, presenting little
insecticidal action on A. diaperinus and; (3) the mastruz extract presented
repellentaction and attractive to the concentrations of the 2,5; 5,0 and 10% and 7,5%
respectively.