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Interações de agentes naturais no controle populacional de Spodoptera frugiperda Smith (1797) (Lepidoptera:Nocturidae) em milho (Zea mays)
(Universidade Federal de São Carlos, 2002-05-28) Mantrangolo, Walter José Rodrigues; Dias, Angélica Maria Penteado Martins; https://lattes.cnpq.br/8637344058859147
It was evaluated the possible interactions among the following agents of natural control of Spodoptera frugiperda (Lepidoptera: Noctuidae): Campoletis flavicincta (Hymenoptera: Ichneumonidae), the Nuclear Polyhedrosis Virus (NPV - Sf) and different maize genotypes with different levels of genetic resistance [Resistant exotic parental Zapalote Chico (ZC) (Zea mays), the adapted parental BR 105, and four semi-exotic populations, with different percentages of gene introgression: 50% of ZC + 50% of BR 105 (or simply F1), 25% of ZC + 75% of BR 105 (backcross 1 or simply BC1), 12,5% of ZC + 87,5% of BR 105 (or BC2) and 6,25% of ZC + 93,75% of BR 105 (or BC3)]. The incubation period of the eggs of C. flavicincta was approximately 48 hours. Most of the caterpillars of S. frugiperda contained more than one eggs of the parasitoid. However, 24h after eggs eclosion, it was observed the presence of only one developed larvae in the same caterpillar. Probably there is a competition among newly hatched larvae and through physical attack only one survives. Females of the parasitoid laid more eggs in healthy caterpillar than in infected one, when they did not have choice option. When in contact with healthy caterpillars and infected by NPV - Sf at the same time, there was not difference in the number of deposited eggs, probably because the female could not discriminate between of healthy or NPV infected host. In olfactometer test, healthy S. frugiperda larva and corn leaf attracted 50% of the C. flavicincta females. In the treatment with infected caterpillars and your leaf, they were attracted 32,1% of the females. Where just had leaves, that value was of 14,3% and the witness, without any scent source, it attracted only 3,5% of the females. To discriminate healthy hosts of having infected can minimize the negative impact of NPV - Sf on the parasitoids. Increase of the size of the caterpillar implicates in a reduction in the efficiency of the virus. The united use of virus and parasitoid in laboratory increased the mortality of caterpillars of S. frugiperda in laboratory, when compared with the treatment where was just used the virus. As larger the interval of time between parasitism and infection, larger the survival of C. flavicincta. The previous infection with NPV - Sf reduced the emergency of the parasitóide, mainly in caterpillars infected in the 2nd and 3rd days of life. Not only originated females of caterpillars infected by the virus they were capable to transmit the pathogen for healthy caterpillars, but also those females initially exempt of the virus, but that were coupled with males originating from of infected caterpillars. In laboratory, the genetic materials didn't indicate significant differences in the biological parameters (efficiency of parasitism, weight of healthy caterpillars and sponged, weigh of the pupas, duration of the phase pupal and sexual reason of the host and of the parasitoid). In the field smallest number was collected of caterpillars of size 3 and any caterpillar of size 4 in ZC, besides smallest number of caterpillars of S. frugiperda, of pupae of the parasitoid and where the damage level was smaller, indicating that there was effect of that material.
Entre o peixe e o dendê; etnoecologia do povo dos Marimbús (Chapada Diamantina - BA)
(Universidade Federal de São Carlos, 2002-05-28) Moura, Flávia de Barros Prado; Nordi, Nivaldo; https://lattes.cnpq.br/8168865557947289; Marques, José Geraldo Wanderley
This study documents traditional ecological knowledge by a human population living in Chapada Diamantina, Northeast Brazil. The field work was carried out from June 1998 to May 1999 and included: open-ended interviews, structured interviews, direct observation, questionnaires and tours guided by fishermen. Fish and plants species were collected and taxonomically identified. The consistence of fishermen´s knowledge was observed through compared cognition tables. Local knowledge related to spatiotemporal distribution of fish, ethology, feeding behavior and fish reproduction are fundamental for fishing activities. Plant use is extensive: 131 species of plants medicinally, 69 species for food, 44 for firewood, 38 for house building, and 23 for fishing practices. 72 products from 52 species of animals were reported to be used for prevention and cure 40 physically or spiritually derived illnesses. Most of the medicines (55 %) are derived from by-products of animals normally hunted for food intention. Traditional knowledge about fish species was gathered and proved to be consistent with data from scientific literature. Local knowledge is fundamental for fishing activities and should be taken into account in the planning of sustainable management for the area, which has been set aside by government as an APA (Environmental Protection Area).