Natural Parasitism in Acromyrmex landolti Forel (Hymenoptera, Formicidae) in Pastures of Bahia, Brazil

This study aimed to evaluate the occurrence of natural parasitism in Acromyrmex landolti Forel, identify parasitoids associated to the species and to estimate parasitism rates. The experiment was conducted from January to May 2012 in Itapetinga, BA. 20 nests were excavated, removing eggs, larvae, pupae and adults for counting and evaluating parasitism, isolating adult parasitoids and parasitized ant larvae. Parasitism by Mimopria sp. (Diapriidae: Diapriini) occurred in nine nests, with an average rate of 12% of parasitized larvae. It is the first record of parasitism of Mimopria Holmgren in an Attini species

Natural Parasitism in Acromyrmex landolti Forel (Hymenoptera, Formicidae) in Pastures of Bahia, Brazil

This study aimed to evaluate the occurrence of natural parasitism in Acromyrmex landolti Forel, identify parasitoids associated to the species and to estimate parasitism rates. The experiment was conducted from January to May 2012 in Itapetinga, BA. 20 nests were excavated, removing eggs, larvae, pupae and adults for counting and evaluating parasitism, isolating adult parasitoids and parasitized ant larvae. Parasitism by Mimopria sp. (Diapriidae: Diapriini) occurred in nine nests, with an average rate of 12% of parasitized larvae. It is the first record of parasitism of Mimopria Holmgren in an Attini species

Ocorrência sazonal, predação e parasitismo de Leucoptera coffeella (Guérin-Méneville, 1842) (Lepidoptera: Lyonetiidae) em cafeeiros associados a grevíleas

The leaf miner, Leucoptera coffeella, is a key pest in coffee crops, causing significant losses. This work aimed to study the seasonal occurrence of leaf miner and the infestation rates of parasitism and predation natural pest in coffee associated with grevillea trees in Southwestern Bahia, Brazil. The experiment consisted of five fields (treatments) and four replicates, totaling 20 plots. Treatments were defined by the spacing of grevillea associated with Catuaí (IAC 144): Treatment 1 – shaded - without grevillea; Treatment 2 - 18x18m = 31 grevilleas.ha-1; Treatment 3 - 12x12m = 69 grevilleas.ha-1; Treatment 4 - 6.0 x12m = 139 grevilleas.ha-1 and Treatment 5 - 6.0 x6,0m = 277 grevilleas.ha-1. The plots consisted of four (T4 and T5) and six coffee plants (T1, T2 and T3) around one grevillea plant. We quantified the number of leaves with mines, mines per leaf, total mines, mine predated and parasitized from September/2011 to June/2012. The results indicated that the influence of the increased density of grevillea trees the population of the leaf miner is not uniform over time, presenting unfavorable the period September to December 2011, to densities in the band 180-220 grevilleas.ha-1, from which promotes the growth of the insect population. In the period from February to June 2012, the increase in the density of grevillea trees acts negatively on the pest population. The predation has the same trend as the leaf miner infestation in relation to the density of grevillea trees, while the parasitism does not show a pattern of behavior with respect to that variable. The relation between predation and parasitism is positive.O bicho-mineiro, Leucoptera coffeella, é praga chave do cafeeiro, causando perdas significativas na produção. Objetivou-se, neste trabalho, estudar a ocorrência sazonal do bicho-mineiro e as taxas de infestação, parasitismo e predação natural da praga em cafeeiros arborizados com grevíleas, na região Sudoeste da Bahia, Brasil. O experimento foi composto por cinco campos de observação (tratamentos) e quatro repetições, totalizando 20 parcelas. Os tratamentos foram definidos pelo espaçamento das plantas de grevílea associadas ao cafeeiro Catuaí Vermelho (IAC 144): Tratamento 1 – pleno sol – sem grevílea; Tratamento 2 – 18x18m = 31 grevíleas.ha-1; Tratamento 3 – 12x12m = 69 grevíleas.ha-1; Tratamento 4 – 6,0x12m =139 grevíleas.ha-1; e Tratamento 5 – 6,0x6,0m = 277 grevíleas.ha-1. As parcelas consistiram de quatro (T4 e T5) e seis plantas de café (T1, T2 e T3), ao redor de uma planta de grevílea. Foram quantificadas as folhas com minas, minas por folha, total de minas, minas predadas e minas parasitadas, de setembro/2011 a junho/2012. Os resultados indicaram que a influência do aumento da densidade de grevíleas na população do bicho-mineiro não é uniforme ao longo do tempo, apresentando-se desfavorável no período de setembro a dezembro de 2011, até densidades na faixa de 180 a 220 grevíleas.ha-1, a partir das quais o crescimento populacional do inseto é favorecido. No período de fevereiro a junho de 2012, o aumento na densidade de grevíleas atuanegativamente na população da praga. A predação apresenta a mesma tendência da infestação do bicho-mineiro em relação à densidade de grevíleas, enquanto que o parasitismo não apresenta um padrão de comportamento em relação àquela variável. A relação entre predação e parasitismo é positiva

Desempenho fisiológico de sementes de algodão cultivadas em Luís Eduardo Magalhães, Bahia

This study was conducted at the State University of seed technology laboratory of Southwest Bahia, Campus Victory Conquest, UESB, to evaluate the physiological quality of cotton seeds (Gossypium hirsutum L.), using five cultivars (DP 604, FM 993, BRS 368, GMT 642 and DELTA OPAL). Seeds were subjected to the following tests: water content, weight of a thousand seeds, germination, first count, emergence speed index, emergency, shoot length, dry mass of seedlings and electrical conductivity. The experimental design was completely randomized, with four replications of 50 seeds per treatment. The cultivar TMG 642 demonstrated low physiological seed quality when compared with the DP 604 cultivars, FM 993, BRS 368, and DELTA OPAL. Germination tests, electrical conductivity and germination rate index showed efficiency in the separation of cotton seed varieties in force levels.O presente trabalho foi desenvolvido no laboratório de tecnologia de sementes da Universidade Estadual do Sudoeste da Bahia, Campus de Vitória da Conquista UESB, com objetivo de avaliar a qualidade fisiológica de sementes de algodão (Gossypium hirsutum L.), utilizando-se cinco cultivares (DP 604, FM 993, BRS 368, TMG 642 e DELTA OPAL). As sementes foram submetidas aos seguintes testes: teor de água, peso de mil sementes, germinação, primeira contagem de germinação, índice de velocidade de emergência, emergência, comprimento da parte aérea, massa seca das plântulas e condutividade elétrica. O delineamento experimental utilizado foi o inteiramente casualizado, em quatro repetições de 50 sementes por tratamento. A cultivar TMG 642 demonstrou baixa qualidade fisiológica das sementes, quando comparados com as cultivares DP 604, FM 993, BRS 368, e DELTA OPAL. Os testes de germinação, condutividade elétrica e índice de velocidade de germinação mostraram eficiência na separação de cultivares de sementes de algodão em níveis de vigor

Isolation of Chavibetol and Methyleugenol from Essential Oil of <i>Pimenta pseudocaryophyllus</i> by High Performance Liquid Chromatography

A high performance liquid chromatography (HPLC) method was developed for the simultaneous isolation, on a semi-preparative scale, of chavibetol and methyleugenol from the crude essential oil of P. pseudocaryophyllus leaves. The purity of the isolated compounds and their quantifications were developed using GC/FID. Chavibetol was isolated with high purity (98.7%) and mass recovery (94.6%). The mass recovery (86.4%) and purity (85.3%) of methyleugenol were lower than those of chavibetol. Both compounds were identified on the basis of spectral analysis. The results suggest that the method can provide chavibetol with high purity, mass recovery, and productivity from crude essential, which will be used in bioassays against stored insect pests