Academic literature on the topic 'Mexican bean weevil'

The common bean, Phaseolus vulgaris L., is one of the most important sources of protein in Ethiopia and other developing countries. However, the Mexican bean weevil, Zabrotes subfasciatus (Boheman), is a major constraint of stored common bean that causes qualitative and quantitative losses. This study was conducted to assess farmers’ knowledge and perceptions of Mexican bean weevil, to examine farmers’ pest management practices, and to identify challenges of pest management practices to develop integrated pest management (IPM) strategies. A survey of 148 smallholder common bean farmers was conducted at Mareka and Loma districts in southern Ethiopia. The majority (75%) of the farmers stored common bean in polypropylene bags while less than 10% of the farmers stored beans in ‘Diya’ (a traditional storage structure). Most (60.8%) farmers stored their beans in seed (threshed) form, and the majority (63.5%) of them stored their beans for 3-5 months. The majority of the farmers had knowledge about the Mexican bean weevil; they could identify damaged seeds based on the ‘holes’ on the seed (72.3%) and circular ‘windows’ on the seed (20.0%). About 45% of the farmers mentioned the high amount of loss at the time of storage. In addition, most farmers (53.4%) estimated 26-50% loss in storage. Most farmers reported the use of pesticidal plants for control of Mexican bean weevil, while only a few farmers reported they had applied insecticide in their store. Education level and family size had a positive and statistically significant impact on the use of pesticidal plants for the control of Mexican bean weevil. Furthermore, education level also influences the use of chemical insecticide. Results highlighted the need to use improved storage technology and to train farmers in postharvest handling practices as a component to develop IPM approach in order to minimize losses occurring along the value chains of the common bean.

The presence of arcelin protein in the seeds of common bean, Phaseolus vulgaris L., provides resistance to the Mexican bean weevil and to a lesser degree, the common bean weevil. Fast, accurate identification of single seeds containing arcelin facilitates the transfer of alleles for each of four different arcelin types through standard crossing procedures. Seed yields and other traits of near-isogenic lines that contain different alleles were comparable to the standard parent, Porrillo 70. Genotypic mixtures containing resistant and susceptible seeds produced seed yields comparable to Porrillo 70, which suggests that heterogeneous populations offer the potential for stable resistant cultivars.

The Mexican bean weevil Zabrotes subfasciatus (Coleoptera: Chrysomelidae: Bruchinae) is an important pest of stored beans in tropical regions. The efficiency of kaolin [with or without neem (Azadirachta indica) oil] and diatomaceous earth (DE) (standard treatment) was studied in laboratory aiming to obtain alternatives for chemical control of this insect. Insects were confined in plastic vials containing beans treated with kaolin (2, 4 and 8g kg-1), kaolin + neem [2g kg-1(5% neem oil)], diatomaceous earth (1g kg-1) and control. Mortality of adult insects, number of eggs and F1generation beetles emergency were assessed. Kaolin caused mortality of Z. subfasciatus, however higher periods and doses than DE were necessary to promote high mortality (100% or close). Kaolin treatments also affected female behavior because many eggs were placed in the vials walls. Number of emerged adults (F1) was similar between DE and kaolin; hence, kaolin constitutes a promising tool to the management of Z. subfasciatus. The mixture of kaolin and neem oil was not efficient in the control of Z. subfasciatus.

AbstractCommon bean (Phaseolus vulgarisL.) is amongst the most important grain legume crops in Africa in general, and Ethiopia in particular. The Mexican been weevil (Zabrotes subfasciatusBoheman) heavily attacks the grain of common bean. A total of 300 common bean entries were subjected to a ‘no-choice’ test at Melkassa Agricultural Research Centre, Ethiopia, using a randomized complete block design with three replications, to evaluate for resistance to the Mexican bean weevil. Data on insect and seed traits were collected and a significant level (P<0.01) of variation in all parameters measured was observed amongst genotypes. Relative resistance was recorded in landraces, improved genotypes and breeding lines, but the resistant genotypes, RAZ-11, RAZ-36, RAZ-2, RAZ-44, RAZ-120, RAZ-40 and MAZ-203, showed consistently complete resistance, with zero index of susceptibility value. Two other promising entries were also identified from the breeding lines (SCR-11) and landrace collections (NC-16) of Ethiopia. Stratified ranking diagrams showed that accessions from different eco-geographical origins in Ethiopia and those with different colours showed different patterns of response to infestation. The Ethiopian bean breeding programme should take up the resistant genotypes for a comprehensive yield trial at the national level and direct release them as commercial varieties. The incorporation of bean weevil resistance genes into adapted varieties through backcross breeding techniques, supported with marker assisted selection, seems to be the best strategy not only in terms of time saving but also in terms of effectiveness and efficiency.

Abstract Plants that have potential as alternative food source (floral nectar, pollen and plant tissues) to the boll weevil during the intercropping season were evaluated considering the prevalent conditions of Cerrado in the Central Brazil. Initially, we tested the nutritional adequacy for the survival of the insect of flower resource (pollen and nectar) provided by eight plant species (fennel, mexican sunflower, castor bean, okra, hibiscus, sorghum, pigeonpea and sunn hemp). Subsequently, we tested if the resources provided by the selected plants continued to be exploited by the boll weevil in the presence of cotton plant, its main food source average longevity of boll weevil adults was significantly longer when they were fed on hibiscus’ flowers (166.6 ± 74.4) and okra flowers (34.7 ± 28.9) than when they fed on flowers of other six species. Subsequently, the preference of the boll weevil in the use of resources was compared between okra or hibiscus and cotton plants, in dual choice experiments. Boll weevils preferred plants of the three species in the reproductive stages than those in vegetative stages. Although the cotton plant in the reproductive stage was the most preferred plant of all, boll weevils preferred flowering okra and hibiscus than cotton at the vegetative stage.

AbstractMexican bean weevil, Zabrotes subfasciatus Boheman, is a significant pest of stored beans (Phaseolus vulgaris L.) that causes considerable loss in the quality and quantity of bean grain in Africa. In the past two to three decades, researchers have attempted to identify botanicals with better insecticidal potential against storage pests. However, there is a lack of information on the potency of botanical combinations, their toxicology, and optimal application rates. This study was conducted to examine the bioefficacy of unitary and binary botanical combinations of Jatropha curcas (L.), Datura stramonium (L.), Chenopodium ambrosioides (L.), Schinus molle (L.), and Azadirachta indica (A. Juss) against Z. subfasciatus at 1% and 2% w/w dosages. The insecticidal activities of the botanicals were measured based on their effect on adult mortality of Z. subfasciatus and progeny reduction, grain weight loss, and weevil perforation index. Among botanical admixtures, binary combinations of C. ambrosioides + D. stramonium, J. curcas + C. ambrosioides, and S. molle + C. ambrosioides were the most potent. They resulted in the highest mortality of Z. subfasciatus, low weevil perforation index or none, and grain weight loss at the most moderate test dosage (1% w/w). Treatment with C. ambrosioides resulted in the highest efficacy when applied individually. We failed to observe any notable difference in toxicity between dosage levels among the binary botanical combinations. However, the effectiveness of unitary formulations improved with the increase in dosage rate. Application of botanicals did not adversely affect bean seed germination. Our study suggests that botanicals in binary mixtures may enhance the potency of constituent components for effective control of Z. subfasciatus.

ABSTRACT Common beans (Phaseolus vulgaris L.) are one of the most important protein sources worldwide. However, infestation by bruchids compromises the storage of these beans after harvest. The objective of this study was to determine the emergence rate of Zabrotes subfasciatus (Coleoptera: Chrysomelidae) in four P. vulgaris varieties (Carioca Pitoco, Enxofre, Gorgutuba Vermelho, and Rosinha) cultivated in the southwestern Amazon (State of Acre, Brazil). The grains from each variety were infested with 50 non-sexed adult Z. subfasciatus, and the insects were collected 13 days after initiating the bioassays. The adult progeny was collected from each plant variety on alternate days from the beginning to the end of the emergence period, and they were counted (number of insects/jar). The sum of emerged insects per day (SEd) was determined from the beginning of the emergence period, from which the accumulated emergence was calculated (SEa= ΣSEd, % day). There were differences in the emergence rates of Z. subfasciatus among the bean varieties, with the rates being lower in the Gorgutuba Vermelho variety. Although this bean variety had the lowest peak of adult insect emergence, the period of insect development was not of increased length in this variety compared to the other varieties. In general, the Gorgutuba Vermelho variety appears to be resistant to Z. subfasciatus.

Bean weevil, Zabrotes subfasciatus (Boheman, 1833) (Coleoptera: Chrysomelidae) is considered the main insect-pest of the stored beans. Currently its control is achieved through protective spray (fumigations). New techniques of alternative control are being used to minimize the use of insecticides such as the use of resistant cultivars and insecticide plants through powders, extracts and oils. This work was divided into four chapters. The first consisted of a review of literature. In the second evaluated the method of control through the use of powders plants of different parts of plants from three species of the genus Annona, seeds powders of Piper nigrum L. and plaster. In the third it has developed a method of control through the use of powders plants of different parts of plants from three species of the genus Annona; powder seeds of Piper nigrum L.; Ageratum conyzoides L. (branch and leaf); Ricinus communis L. (leaf) and Azadirachta indica A. juss associated with plaster. And the fourth was tested after four species of plants: Piper nigrum L., Chenopodium ambrosioides, Coriandrum sativum L. and Cymbopogon citratus (DC) Stapf and plaster. All experiments were conducted aiming to observe possible adverse effects of these materials on the Z. subfasciatus. In general, two couples of newly emerged adults, Z. subfasciatus were placed in plastic pots of 250 mL. Where in the second chapter was used 10 g of beans, mixed with 1 g of the powder of each anonácea (leaves and branches, individually), the black pepper powder and plaster. The third chapter 10 g of beans, mixed with 0.5 g of powder of each treatment and 0.5 g of plaster, thereby completing 1 g of different powders of plants associated with plaster. In the forth chapter 5 g of the bean group Rio, at concentrations of 0.5, 0.25; 0125 g of powder per container. Were evaluated in the second chapter: cumulative mortality of first-eighth day, oviposition in the thirteenth day and quantity of emergence holes in the eighth fortieth day after the installation of bioassays. In the third chapter: cumulative mortality of first-ninth day (alternate days), oviposition on the fifteenth day, number of emergence holes in fortieth seventh day, after the installation of the bioassays, and the fourth chapter: mortality, oviposition, emergency in 2º generation of adults, number of beans with eggs deposited on the surface by adults emerged and repellency of Z. subfasciatus. In the second chapter more effective treatments were the powder of black pepper, causing rapid death in adults and consequently lower numbers of eggs and emergence holes in the grains. In the third chapter was the most effective treatment the powder of the black pepper, causing rapid death in adults and also interfered in oviposition and the number of holes for emergencies of insects. And in the last chapter found that the powder of P. nigrum L. and C. ambrosioides showed highly toxic effect on adults of Z. subfasciatus causing 100% of death until the 5º day, not providing fertile eggs in grain treated with these materials, the emergence of adults impossible to Z. subfasciatus in the three concentrations were tested and repellents for adults, the concentration of 0.25 g / 5 g beans. The peak of oviposition occurred at 4 and 5 days after the emergence of adults of Z. subfasciatus. For the other powder, did not interfere in the variables analyzed, because the treatment did not differ statistically witness except in the variable repellency of Z. subfasciatus, because based on the Index of Preference of the powder C.citratuswa srepellent.<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>O caruncho-do-feijão, Zabrotes subfasciatus (Boheman, 1833) (Coleoptera: Chrysomelidae) é considerado o principal inseto-praga dos grãos de feijão armazenado. Atualmente seu controle é realizado através de pulverização protetora (fumigações). Novas técnicas de controle alternativo vêm sendo utilizadas para minimizar o uso de inseticidas, como a utilização de cultivares resistentes e plantas inseticidas por meio de pós, extratos e óleos. Esse trabalho foi dividido em quatro capítulos. O primeiro constituiu-se de uma revisão de literatura. No segundo avaliou-se o método de controle através da utilização de pós vegetais de diferentes partes de plantas de três espécies do gênero Annona, do pó das sementes de Piper nigrum L. e do gesso. No terceiro desenvolveu-se um método de controle através da utilização de pós vegetais de diferentes partes de plantas de três espécies do gênero Annona; do pó das sementes de Piper nigrum L.; Ageratum conyzoides L. (ramo e folha); Ricinus communis L. (folha) e Azadirachta indica A. juss associados ao gesso. E no quarto foram testados pós de quatro espécies vegetais: Piper nigrum L., Chenopodium ambrosioides, Coriandrum sativum L. e Cymbopogon citratus (DC.) Stapf e do gesso. Todos os experimentos foram realizados visando observar possíveis efeitos adversos desses materiais sobre Z. subfasciatus. Em geral, dois casais de adultos recém-emergidos, de Z. subfasciatus foram colocados em potes plásticos de 250 mL. Onde no segundo capítulo foi utilizado 10 g de feijão, homogeneizado com 1 g dos pós de cada anonácea (folhas e ramos, individualmente), pó da pimenta-do-reino e gesso. No terceiro capítulo 10 g de feijão, homogeneizado com 0,5 g dos pós de cada tratamento e 0,5 g de gesso, completando-se assim 1 g de diferentes pós-vegetais associados ao gesso. No quarto capítulo 5 g de feijão do grupo carioca, nas concentrações de 0,5; 0,25; 0,125 g de pó por recipiente. Foram avaliados no segundo capítulo: mortalidade acumulada do primeiro ao oitavo dia, oviposição no décimo terceiro dia e quantidade de orifícios de emergência no quadragésimo oitavo dia. No terceiro capítulo: mortalidade acumulada do primeiro ao nono dia (dias alternados), oviposição no décimo quinto dia, número de orifícios de emergência no quadragésimo sétimo dia; e no quarto capítulo: mortalidade, oviposição, emergência na 2ª geração de adultos, número de feijão com ovos depositados em sua superfície por adultos emergidos e repelência de Z. subfasciatus. No segundo capítulo os tratamentos mais eficazes foram os pós de pimenta-do-reino, que causou rápida mortalidade em adultos e conseqüentemente menor números de ovos e de orifícios de emergência nos grãos. No terceiro capítulo o tratamento mais eficaz foi o pó de pimenta-do-reino, que causou excelente mortalidade em adultos e também interferiu na oviposição e no número de orifícios de emergências dos insetos. E no ultimo capítulo verificou-se que os pós de P. nigrum L. e C. ambrosioides apresentaram efeito altamente tóxico aos adultos de Z. subfasciatus causando 100% de mortalidade até o 5º dia, não proporcionando ovos férteis nos grãos tratados com estes materiais, impossibilitaram a emergência dos adultos de Z. subfasciatus nas três concentrações testadas e foram repelentes aos adultos, na concentração 0,25 g / 5 g de feijão. O pico de oviposição ocorreu no 4º e 5º dias após a emergência de adultos de Z. subfasciatus. No caso dos outros pós, não interferiram nas variáveis analisadas, pois não diferiram estatisticamente do tratamento testemunha com exceção na variável repelência de Z. subfasciatus, pois com base no Índice de Preferência o pó do C. citratus foi repelente.

Submitted by (edna.saturno@ufrpe.br) on 2016-11-23T15:22:35Z No. of bitstreams: 1 Cleia Gomes Vieira e Silva.pdf: 397357 bytes, checksum: 224e5b48f721843c7d8a272b57e0013f (MD5)<br>Made available in DSpace on 2016-11-23T15:22:35Z (GMT). No. of bitstreams: 1 Cleia Gomes Vieira e Silva.pdf: 397357 bytes, checksum: 224e5b48f721843c7d8a272b57e0013f (MD5) Previous issue date: 2007-07-02<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>Plants constitute natural sources of insecticide substances and have been used by mankind since Antiquity. It is also known that medicinal plants present great quantities of secondary compounds such as alkaloids, terpens, flavonoids and steroids which promote high resistance to the onset of pests and diseases. The genus Croton, which is made up of species that occur naturally in the State of Pernambuco, where many of them are used in the popular medicine and characterize themselves by the production of essential oil, owns expressive relevance founded on their sources of fixed and volatile components with recognized biological activity in the treatment of various illnesses. The knowledge that medicinal plants present high resistance to the onset of diseases and pests has led us to investigate the potential insecticide of crude ethanolic extracts from different parts of plants of the genus Croton against Plutella xylostella L. and of the essential oil of the species C. grewioides against Zabrotes subfasciatus Boheman. All the investigated plants are native to the biome in Pernambuco with use in the popular medicine by the community where its occurrence is reported. The crude extracts were obtained through cold maceration, ethanol being used as solvent, from leaves and stalks of the species Croton jacobinensis Baill, C. micans Muell., C. rhamnifolius H.B.K and C. sellowii Baill. The essential oil, on the other hand, was obtainedthrough hydro-distillation from the leaves and stalk of C. grewioides. These extracts were diluted into previously determined concentrations by means of a pilot experiment and their activities were tested for the development and survival of Plutella xylostella L. To do so, with the aid of Potter’s Tower, eight-cm diameter cabbage disks, Brassica oleracea var. acephala L., were ground with different concentrations of the ethanolic extracts and offered to caterpillars confined into Petri’s dishes. Among the studied extracts, the ethanolic extract from leaves of C. rhamnifolium was the most toxic at the larval phase, followed by the ethanolic extract from the stalk of the same species, presenting CL50 of 14.95 and 42.40μg mL-1, respectively. The interference of the extract of C. rhamnifolius in the development of P. xylostella was also noticed. From the stalk and leaves of Croton grewioides Baill essential oils were extracted through hydro-distillation and then analyzed by GC/MS. This analysis revealed that both oils are made up of 22 compounds, in which the predominant chemical class was that of the phenylpropanoids, whose major representative was (E)-anetol (65.5% in the leaves and 47.8% in the stalk). The fumigant effect of both essential oils was assessed for the woodworm of beans, Z. subfasciatus, which presented itself as potential for the control of this pest. The essential oil of leaves presented itself about 3.4 times more effectivethan the essential oil from the stalk and the estimated values for the CL50 were 4.0 and 13.7 μg mL-1 of air, respectively.<br>As plantas constituem fontes naturais de substâncias inseticidas, e vêm sendo utilizadas pela humanidade desde a antiguidade. As plantas medicinais apresentam grandes quantidades de compostos secundários como alcalóides, terpenos, flavonóides e esteróides, que promovem alta resistência ao ataque de pragas e de doenças. O gênero Croton, que é constituído por espécies que ocorrem naturalmente no estado de Pernambuco, onde muitas delas são utilizadas na medicina popular. Estas plantas se caracterizam pela produção de óleo essencial e detém expressiva relevância alicerçada em suas fontes de componentes fixos e voláteis com reconhecida atividade biológica no tratamento de várias enfermidades. O conhecimento de que plantas medicinais apresentam alta resistência ao ataque de doenças e pragas motivou a investigação do potencial inseticida de extratos etanólicos brutos de diferentes partes de plantas do gênero Croton no controle de Plutella xylostella L. e do efeito fumigante de óleo s essenciais da espécie C. grewioides contra Zabrotes subfasciatus Boheman. Todas as plantas investigadas são nativas do bioma pernambucano com uso na medicina popular pela comunidade onde sua ocorrência é registrada. Os extratos brutos foram obtidos por maceração a frio, utilizando como solvente o etanol, a partir de folhas e caules das espécies Croton jacobinensis Baill, C. micans Muell., C.rhamnifolius H.B.K. e C. sellowii Baill. Já o óleo essencial foi obtido por hidrodestilação a partir de folhas e caule de C. grewioides. Os extratos obtidos foram diluídos em concentrações previamente determinadas mediante experimento piloto e tiveram suas atividades testadas sobre o desenvolvimento e sobrevivência de Plutella xylostella L. Para isto, com auxílio de torre de Potter, discos de oito cm de diâmetro de folhas de couve, Brassica oleracea var. acephala L., foram pulverizados com diferentes concentrações dos extratos etanólicos, e oferecidos às larvas confinadas em placas de Petri. Dentre os extratos estudados, o extrato etanólico de folhas de C. rhamnifolium foi o mais tóxico à fase larval, seguido do extrato etanólico de caule da mesma espécie, apresentando CL50 de 14,95 e 42,40μg mL-1, respectivamente. Observou-se ainda uma interferência do extrato de C. rhamnifolius no desenvolvimento de P. xylostella. O óleo essencial obtido a partir do caule e folhas de Croton grewioides Baill. foi analisado por CG/EM. Um total de 22 compostos foi identificado. A classe química predominante foi fenilpropanóide, cujo representante majoritário, o (E)-anetol apresentou percentual de 65,5% no óleo de folha, e 47,8% no óleo do caule. Bioensaio de fumigação foi realizado contra o caruncho do feijão Z. subfasciatus. O óleo essencial de folhas foi cerca de 3,4 vezes mais tóxico eficaz do que o óleo essencial do caule cujos valores estimados para a CL50 foram 4,0 e 13,7 μgL-1 de ar, respectivamente.