Acanthoscelides Obtectus Research Articles

Progresses in lowland pulse insect pest management in Ethiopia

Grain legumes are one of the important cash crops for Ethiopian smallholder farmers and a significant agricultural commodity contributing to export earnings. Lowland pulses are comparatively inexpensive sources of protein in Ethiopia. However, these economically important crops are affected by various pests. Among the most damaging in storage are bruchids (Acanthoscelides obtectus, Zabrotes subfasciatus, and Callosobruchus spp.), while in production fields, the primary pests include the bean stem maggot (Ophiomyia spp.), African bollworm (Helicoverpa armigera), and aphids (Aphis craccivora Koch). Estimated yield losses due to bean stem maggot and African bollworm range from 11-100% and 12-16%, respectively. Various pest control strategies have been employed, including the use of resistant varieties, biological control, botanical treatments, and chemical control. This review summarizes relevant scientific studies on these economically important crops, the associated insect pests, the aggravating factors in Ethiopia, and available management options.

Purification and characterization of α-amylase from Acanthoscelides obtectus (Say) (Coleoptera: Chrysomelidae)

Acanthoscelides obtectus is one of the most notorious pests of stored kidney beans (Phaseolus vulgaris) worldwide. Kidney beans are an important source of food for these insects. α-Amylase is the main carbohydrate-digesting enzyme in animals including insects. In the current study, the biochemical analysis revealed higher α-amylase activity (U/ml) in 3rd and 4th larval instars but decreased gradually in subsequent developmental stages. However, the specific activity (U/mg) interestingly was highest in 1st instar and decreased in further developmental stages. During qualitative analysis of α-amylase using starch-agar and native PAGE, the maximum zone of starch lysis and a prominent band on the gel was observed in 3rd and 4th larval stages. The molecular mass of the native enzyme was also estimated and found to be 30.34 kDa. The crude α-amylase was further purified by ammonium sulfate precipitation, gel filtration on a Sephadex G-75, and ion exchange chromatography on the DEAE cellulose column. The purified amylase was found to be a monomer with a molecular mass of 15 kDa. The specific activity of the purified enzyme increased from 1.74 U/mg in the crude sample to 166.35 U/mg in the final purification step resulting in 95-fold purification with a yield of 11.14%. Further characterization of purified α-amylase revealed a pH optimum of 7.0 and a temperature optimum of 35 °C. Lineweaver-Burk plot analysis revealed Km and Vmax to be 0.09% and 3.3 U/mL, respectively. Oxalic acid, tannic acid, and HgCl2 significantly inhibited the enzyme, while the Na+, Ca++, and Mg++ ions acted as activators. In conclusion, the study revealed, the highest α-amylase activity in 3rd and 4th larval stages of Acanthoscelides obtectus followed by native and SDS PAGE resulting in molecular mass of 30.34 and 15 kDa respectively.

Selection for Late Reproduction Leads to Loss of Complex I Mitochondrial Capacity and Associated Increased Longevity in Seed Beetles.

Mitochondria play a key role in aging. Here, we measured integrated mitochondrial functions in experimentally evolved lines of the seed beetle Acanthoscelides obtectus that were selected for early (E) or late (L) reproduction for nearly 4 decades. The 2 lines have markedly different lifespans (8 days and 13 days in the E and L lines, respectively). The contribution of the NADH pathway to maximal flux was lower in the L compared to the E beetles at young stages, associated with increased control by complex I. In contrast, the contribution of the Succinate pathway was higher in the L than in the E line, whereas the Proline pathway showed no differences between the lines. Our data suggest that selection of age at reproduction leads to a modulation of complex I activity in mitochondria and that mitochondria are a functional link between evolutionary and mechanistic theories of aging.

Transgenerational Sub-Lethal Pyrethroid Exposure Affects Shape Variation and Fluctuating Asymmetry in Seed Beetles

One method of crop protection is the application of a widely used group of pesticides—pyrethroids. As xenobiotics, sub-lethal doses of insecticides cause stress in pests, resulting in a change in the shape and size of their organs or bodies. The stress caused by pesticides may lead to acute destabilization of development, but also to transgenerational canalization through the process of genetic assimilation. Fluctuating asymmetry (FA), small random deviations between the right and left sides of bilaterally symmetrical traits, is an outcome of developmental instability and is a measurable indicator of phenotypic response to stress. We exposed four populations of the seed beetle Acanthoscelides obtectus to sub-lethal doses of cypermethrin for ten generations in a laboratory evolution experiment. Using geometric morphometrics, we analyzed size and shape changes and the level of fluctuating asymmetry in untreated beetles and in samples from the fifth and tenth generation. Exposure over ten generations led to an increase in the body size of the beetles, shortening of their pronotum and elongation of their thorax and abdomen. After ten generations of exposure to cypermethrin, FA levels decreased, indicating a canalization of development. This study provides new insights into the phenotypic markers of environmental pollution from agricultural activities.

Impact of varietal diets on the effectiveness of modified atmospheric conditions against the life stages of bean beetle, Acanthoscelides obtectus (Say) (Coleoptera: Chrysomelidae)

The bean beetle Acanthoscelides obtectus (Say) (Coleoptera: Chrysomelidae) is one of the most important pests of legumes in the field and storage, it causes losses in kidney bean and cowpea seeds exceeding 16% in one generation. The physical control method using modified atmospheres is an alternative method to toxic gases in storage. This study aimed to determine the sensitivity of A. obtectus stages that fed on two types of hosts (kidney bean seeds and cowpea seeds) to the modified atmosphere using three concentrations of carbon dioxide (20, 40, and 60%) and different exposure periods at 30 °C and 65% R.H. In general, the results showed that A. obtectus stages reared on cowpeas were more sensitive to CO2 than those reared on kidney beans. Also, the stages are arranged according to their degree of sensitivity to carbon dioxide as follows: adults > eggs > larvae > pupae. According to the LT values, the sensitivity of the external stages of the seeds to carbon dioxide was slightly affected by the type of food, while the internal stages were clearly affected. Complete mortality was achieved after 72 h for adults in all treatments as well as after 7 and 6 days for eggs at 20 and 40% CO2 in both hosts. The exposure periods required to achieve complete mortality were 12, 11, and 10 days for larvae and 12, 12, and 10 days for pupae produced from cowpea seeds, which increased to 14, 12 and 10 days for larvae and 18, 13, and 12 days for pupae produced from kidney bean seeds when treated with 20, 40, and 60% carbon dioxide, respectively. In conclusion, we recommend using the highest concentration of CO2 to control all stages of A. obtectus for 10 days in the case of cowpea seeds and 12 days in the case of kidney bean seeds.

Sex‐specific consequences of host shift for morphology and fluctuating asymmetry in a seed beetle: an experimental evolution approach

AbstractMorphological plasticity may be induced by altering host plants and commonly it is sex‐specific in phytophagous insects. It is hypothesized that stress in insects caused by a host shift leads to morphological changes and developmental destabilization, which may be identified by fluctuating asymmetry. We performed reciprocal transplant experiments in eight replicated populations of the seed beetle Acanthoscelides obtectus (Say) (Coleoptera: Chrysomelidae, Bruchinae) adapted to common bean (Phaseolus vulgaris L., Fabaceae) as its ancestral host and chickpea (Cicer arietinum L., Fabaceae) as a suboptimal host. Using methods of geometric morphometrics we assessed the effects of the short‐ and long‐term host shift on size and shape variation of beetles of both sexes. We also tested the hypothesis that fluctuating asymmetry is lower when the beetles develop within seeds of the ancestral host. Our results showed that females respond more plastically related to their body size and shape of the abdomen, particularly during a short‐term host shift, suggesting that females have a greater importance in maintaining the population on a new host. The level of fluctuating asymmetry is lowest in males that have evolved for generations on bean indicating that they have the most canalized development, so we suggested that symmetry in A. obtectus is maintained by sexual selection. Even if the beetles are adapted to a suboptimal host over many generations, they stabilize their development after returning to the ancestral host. Our work indicates that host shifts may change morphological aspects of the beetles in a sex‐specific manner and consequently influence their developmental trajectories.

Benzyl alcohol, benzyl benzoate and methyl benzoate as bio-insecticides against dried bean beetle Acanthoscelides obtectus (Coleoptera: Tenebrionidae)

Acanthoscelides obtectus is most dangerous pest of preserved beans. The current study used benzyl alcohol (BA), benzyl benzoate (BB), and methyl benzoate (MB) to control A. obtectus. Contact and fumigant toxicity tests were performed to evaluate the efficacy of the used compounds. The contact toxicity assay revealed a significant mortality rate with LC50 reached at low concentrations of 0.57, 0.68, and 0.94 μL/g for BA, BB, and MB, respectively. BA possesses significant fumigant toxicity and outperforms MB and BB, with an LC50 achieved at concentration of 8.91 μL/L. In comparison to the control group, BA, BB, and MB have anti-feedant efficacy against A. obtectus. Furthermore, even at a low concentration of 0.5 μL/g, these compounds induced a significant suppression of A. obtectus F1 progeny production. The BA and BB activities persisted until day 5 after treatment while MB activity sustained for 3 days only. These compounds significantly inhibited acetylcholinesterase, decrease in the level of reduced glutathione (GSH), and elevated malondialdehyde (MDA). In conclusion, BA, BB, and MB are particularly promising choices for controlling the bean beetle A. obtectus because they are low in cost, of natural origin, and the European Food Safety Authority (EFSA) approved their use in animal feed.

Entomopathogenicity Potentials of Molds Isolated from Soil and Plant Debris on Comparative Mortality of Bean Weevil (Acanthoscelides Obtectus)

Entomopathogenic fungi, with their eco-friendly nature, have emerged as promising biocontrol agents for pest management. This study explores the entomopathogenic potential of various isolates, including Aspergillus niger, Aspergillus flavus, Rhizomucor spp., Fusarium spp., and Aspergillus terreus, obtained from soil and plant debris. Confirming their entomopathogenic properties through morphological characteristics, the study aligns with previous research findings on Fusarium spp. and Aspergillus sp. isolation from diverse sources. In entomopathogenic assays against the Beans Weevil, all tested isolates exhibited efficacy, with Rhizomucor spp. demonstrating rapid and sustained mortality rates, reaching 100% within the initial day. Fusarium spp. displayed a cumulative impact, reaching full efficacy by the fourth day. Aspergillus terreus and Aspergillus flavus exhibited robust potential, achieving 100% mortality by the fourth day, while Aspergillus niger displayed slightly delayed onset but reached full efficacy by the third day. These results parallel findings on the effectiveness of Aspergillus species against various insects. Comparative analysis against conventional insecticides revealed entomopathogenic fungi’s superior efficacy, with faster mortality rates than different concentrations of the insecticide. The water control group exhibited a gradual weevil mortality rate, emphasizing the natural course of mortality. The insecticide treatments, even at lower concentrations, consistently outperformed the water control group, highlighting the nuanced relationship between insecticide concentration and efficacy.

Influence of mineral fertilization of common bean (Phaseolus vulgaris L.) on yield and damage by Bean weevil (Acanthoscelides obtectus SAY) in a long-term stationary fertilizer experiment

Influence of mineral fertilization of common bean (Phaseolus vulgaris L.) on yield and damage by Bean weevil (Acanthoscelides obtectus SAY) in a long-term stationary fertilizer experiment

Searching for common bean genotypes resistant to Acanthoscelides obtectus, a primary pest species of stored beans

Searching for common bean genotypes resistant to Acanthoscelides obtectus, a primary pest species of stored beans

Potential for the Use of the Entomopathogenic Fungus Beauveria bassiana in the Biological Control of Cryptolestes ferrugineus and Acanthoscelides obtectus

In this study, the effectiveness of different conidial suspensions of the entomopathogenic fungus Beauveria bassiana (Balsamo) on stored product pests Acanthoscelides obtectus (Bean Seed Beetle) (Coleoptera, Chrysomelidae) and Cryptolestes ferrugineus (Rusty Grain Beetle) (Coleoptera, Laemophloeidae) was aimed to be determined. For this purpose, suspensions of B. bassiana isolate at concentrations of 106, 107, and 108 conidia/ml were used, with sterile water as a negative control and a recommended Declare (EC 25 g/l) as a positive control. The application was set up in three replicates, with 10 adults in each replicate, and applied using the spraying method. To calculate the percentage of mortality, Petri dishes were regularly checked every 24 hours from the application, and the numbers of live and dead adults were recorded. According to the obtained data, it was determined that B. bassiana isolate was effective against C. ferrugineus at a rate of 80% and against A. obtectus at a rate of 56.67% after 168 hours. Among the applied suspensions, the most effective suspension was recorded at 108 conidia/ml. As a result, the entomopathogenic fungus B. bassiana (ET 10) isolate used as a biological control agent, is considered a promising biological control agent against the storage pests C. ferrugineus and A. obtectus.

Release of multiple virus and bruchid resistant Mesoamerican bean germplasm lines PR1303‐129 and PR1743‐44

AbstractPR1303‐129 (Reg. no. GP‐317, PI 702998) and PR1743‐44 (Reg. no. GP‐318, PI 702999) are multiple virus‐ and bruchid‐resistant common bean (Phaseolus vulgaris L.) germplasm lines developed and released cooperatively by the University of Puerto Rico Agricultural Experiment Station, the USDA‐ARS, the Instituto Dominicano de Investigaciones Agropecuarias y Forestales, the Instituto de Ciencia y Tecnología Agrícola, and Zamorano University. The black bean PR1303‐129 and small dark red bean PR1743‐44 combine resistance to Bean common mosaic virus (BCMV), Bean common mosaic necrosis virus (BCMNV), Bean golden yellow mosaic virus (BGYMV) and the common bean weevil [Acanthoscelides obtectus (Say)] with partial resistance to the Mexican bean weevil [Zabrotes subfasciatus (Boheman)]. Marker‐assisted selection was used to identify the presence of the bgm‐1 gene and the SW12 quantitative trait locus (QTL) for BGYMV resistance and the I and bc‐3 genes for resistance to BCMV and BCMNV. The parents of PR1303‐129 and PR1743‐44 were reported to possess the I gene for resistance to BCMV. Greenhouse inoculations were used to confirm the presence of the bc‐3 gene. Lines were screened in the laboratory and field for resistance to bruchids. Mean seed yields of PR1303‐129 and PR1743‐44 in six trials conducted in Puerto Rico were comparable to the check cultivar ‘Verano’. The release of these germplasm lines should contribute to the development of Mesoamerican cultivars for Central America and the Caribbean with enhanced levels of resistance to viral diseases and pests.

Diversity of insect pests of common bean and pigeon pea in the Republic of Congo revealed by DNA barcoding

In Central Africa, the development of leguminous crops is accompanied by a proliferation of pests, such as seed-beetles (Coleoptera: Chrysomelidae: Bruchinae). Integrated biological control against insect pests requires a preliminary phase of early detection and monitoring of potential invasive species, which is often limited by the availability of diagnostic morphological characteristics. DNA barcoding represents a powerful molecular tool for identifying specimens, and the mitochondrial sequences produced can provide information concerning the origins of introduced species. In this study, we characterized the diversity of insect pests present in farmer storage sites and plots of common bean and pigeon pea, by using DNA barcoding of specimens sampled in the five main agricultural regions of the Republic of Congo. The cosmopolitan seed-beetle species Acanthoscelides obtectus (Say, 1831) (Coleoptera: Chrysomelidae: Bruchinae) was recognized as the major pest sampled on common bean. The sub-Saharan species Specularius erythraeus (Pic, 1908) (Coleoptera: Chrysomelidae: Bruchinae) was the main species found in pigeon pea plots, sometimes co-occurring with the cosmopolitan species Callosobruchus maculatus (Fabricius, 1775) (Coleoptera: Chrysomelidae: Bruchinae). A fourth bruchine, Zabrotes subfasciatus (Boheman, 1833), and two moth species were also recognized: a species of the genus Mussidia Ragonot, 1888 (Pyralidae) and the cosmopolitan pest of stored food, Cadra cautella (Walker, 1863) (Pyralidae). These results differ from species lists compiled in the 1980s, thus providing updated knowledge concerning the pest species present in this region and fundamental information for choosing appropriate methods of control.

Evaluation des structures locales de stockage des grains et des graines dans le Département des Bamboutos, Cameroun

Post-harvest food losses remain a major problem in sub-Saharan Africa. A study of local storage structures aimed at carrying out a diagnostic analysis of post-harvest losses in grains and seeds in the Bamboutos department, West region, Cameroon. A questionnaire survey was carried out among 240 producers in 12 villages, spread over 3 subdivisions. Air temperature and relative humidity data were collected over 80 days at two storage stores in this study area. Twelve samples of food infested by insect were taken and deposited in the entomology laboratory of the Faculty of Agronomy and Agricultural Sciences at Dschang University for identification. It emerges from this investigation that corn is the only grain stored by producers. Beans and peanuts are mostly stored seeds, while pistachios and soybeans are seeds stored by few farmers. Three structures are used for grain storage: granaries (86.25%), cribs (10.42%) and stores (3.33%). Among the containers, two are mainly used for seed storage: barrels (58.38%) and bags (39.25%); buckets with lids are used by a few farmers (2.36%). The storage period of corn is between 8 and 12 months. The storage period of peanuts is between 6 and 8 months and beans between 4 and 5 months. The use of chemicals, inert matter (ash) and plant substance (neem) are the three methods of protection used in Bamboutos. Bamboutos storage stores promote the development of molds and insects. Three major groups of biological agents are responsible for spoilage: insects (Callosobruchus maculatus F., Sitophilus zeamais M. and Acanthoscelides obtectus S.), rodents (Rattus norvegicus, Rattus rattus and Mus musculus) and molds. Insects are the pests that cause the most damage to stored products according to 55.42% of producers. According to 23.58% of producers, it is rodents and 15% molds. Farmers estimate that the damage to the stock is between 7% and 30% after destocking of maize. This damage is between 2% and 5% after removal of beans from storage and less than 3% after removal of peanuts. Farmers underestimate the damage caused by pests on corn, which is around 40% after 10 months of storage in granaries. It is therefore essential for Cameroonian farmers to master and respect the storage techniques according to the storage structures and the foodstuffs stored.

Inheritance of the Resistance to Acanthoscelides obtectus (Say.) in a Heterogeneous Inbred Families Population of Common Bean (Phaseolus vulgaris L.)

The bean weevil Acanthoscelides obtectus is one of the world’s main pests of stored beans. The heterogeneous inbred family (HIF) population of near-isogenic lines (NILs) could be an exceptional strategy to study the inheritance of the resistance against A. obtectus. We developed a HIF population of 148 NILs of R-bufa-80-12. The objectives of this research were as follows: (1) to study and understand the genetics of the attack resistance to A. obtectus in a HIF population and (2) to identify the best lines to provide weevil resistance. The pure lines of the HIF population showed a great variability for all the analyzed traits. The traits studied in this research have a normal distribution showing continuous variation, so they are considered to be quantitatively inherited. The heritabilities for resistance traits were low and very low, ranging from 0.09 to 0.17. The heritability for 100 seed weight was the highest, with a significant value of 0.90. The best lines of the HIF population for resistance to A. obtectus comprised Line-45, Line-129, Line-124, Line-142 and Line-47. In general, these lines presented lower preference of adults, and lower consumption in grams and in percentages. However, lines 45 and 129 are the most interesting from a commercial point of view because they combine resistance and seed weight.

A semiochemical view of the ecology of the seed beetle Acanthoscelides obtectus Say (Coleoptera: Chrysomelidae, Bruchinae).

The dried bean beetle, Acanthoscelides obtectus, is an economically important pest of stored legumes worldwide. Tracking the human-aided dispersion of its primary hosts, the Phaseolus vulgaris beans, it is now widespread in most bean-growing areas of the tropics and subtropics. In temperate regions where it can only occasionally overwinter in the field, A. obtectus proliferates in granaries, having multiple generations a year. Despite its negative impact on food production, no sensitive detection or monitoring tools exist, and the reduction of local populations still relies primarily on inorganic insecticides as fumigating agents. However, in the quest to produce more nutritious food more sustainably and healthily, the development of environmentally benign crop protection methods is vital against A. obtectus. For this, knowledge of the biology and chemistry of both the host plant and its herbivore will underpin the development of, among others, chemical ecology-based approaches to form an essential part of the toolkit of integrated bruchid management. We review the semiochemistry of the mate- and host-finding behaviour of A. obtectus and provide new information about the effect of seed chemistry on the sensory and behavioural ecology of host acceptance and larval development.

Cold tolerance of Acanthoscelides obtectus, the bean weevil: Effects of cold acclimation, life stage and strain

The bean weevil, Acanthoscelides obtectus, is one of the most destructive insect pests of stored pulses globally. Cold treatment is a method used for controlling many insect species that are pests of stored-products. To understand if cold treatment can be used to control A. obtectus, we evaluated its cold tolerance at −5 °C and its supercooling point. Firstly, we measured the survival time of eggs, early instars, late instars, pupae, and adults at −5 °C using non-cold-acclimated insects, originally collected in Florida, USA. Secondly, we measured the survival time of late instars and adults at −5 °C using the strain from Florida and a strain from Ontario, Canada, and compared the effect of cold acclimation. To acclimate insects to cold, they were placed for 2 weeks at 15 °C followed by 2 weeks at 10 °C. The Florida strain had a slightly greater survival than the Ontario strain at −5 °C. Results show that at −5 °C, for non-cold-acclimated insects from the Florida strain, the most cold-sensitive stages were the eggs (LT50 of 2.3 d and LT95 of 5.3 d) and the pupae (LT50 of 1.6 d and LT95 of 6.0 d), whereas the late instars (LT50 of 4.0–4.8 d and LT95 of 8.2–8.7 d) were the most cold hardy stage. Cold acclimation increased insect survival time at −5 °C by several days. The egg was the stage with the lowest freezing point, with an average SCP of −27.7 °C. Therefore, all stages of A. obtectus would die instantaneously when exposed to this temperature. These results show that cold treatment can be used to control A. obtectus, particularly in Canada and other northernly regions where winter temperatures can be sustained below −5 °C for months and aeration fans can be used to blow cold ambient air into bins of stored pulses.

Evaluation of long-term residual activity of insecticides against Acanthoscelides obtectus (Say) on common bean in laboratory tests

There are insufficient data about long-term (longer than six-months) residual effects of insecticides against Acanthoscelides obtectus (Say) as an important economic insect pest of stored bean. Therefore, we evaluated, in laboratory conditions, the insecticide potential of recommended rates of commercial formulations: organophosphate malathion (10 mg active ingredient - AI/kg), spinosyns bioinsecticide spinosad (1 mg AI/kg) and pyrethroid deltamethrins (0,25 mg AI/kg, with and without the synergist piperonil butoxide – PBO) after 210-, 265-, 310- and 365-days of post-treatment. Testing was performed on two types of beans with kidney- and cranberry-shaped kernels to evaluate the insecticide residual effects on the survival of weevils, progeny production, and related levels of kernels damage. Survival of weevils depends mainly on adults exposure/living period in treated beans and on the recovering period. Small differencies in weevils survival in each insecticide were recorded. We found increases in progeny and thus higher damage in beans, as manifested effects of sublethal doses only in malathion treated bean. In spinosad treated bean we recorded low levels of progeny and damage, below the economic threshold. In deltamethrin treatments, we recorded weevils avoiding contact with beans, no progeny and no damages. The effect of bean type was very low or non existent. It can be concluded that bioinsecticide spinosad can provide long-term protection of common beans against A. obtectus, while organophosphate malathion has low control potential. Pyrethroid deltamethrins residues cause adults to avoid treated beans and no offspring to appear. The obtained results might have significant impact on better understanding of weevils behaviour in the presence of insecticide residues and on the creation of sustainable pest management programmes.

FAUNA OF SEED BEETLES (COLEOPTERA: CHRYSOMELIDAE, BRUCHINAE) OF THE VYATKA-KAMA REGION AND MIDDLE PRE-URALS

Based on long-term studies (1995-2022), the species composition was established and the fauna of seed beetles (Bruchinae) of the Vyatka-Kama region (including the Kungur island forest-steppe) was analyzed. The studied fauna includes 11 species. For Udmurtia, 10 species are given (of which 3 are for the first time), for the Kirov region - 9 species (3 for the first time), for the northeast of Tatarstan - 6 species (1 for the first time), for the Perm Krai - 5 species (3 for the first time). The fauna is heterogeneous in zoogeographical terms. 2 species ( Bruchus atomarius and B. loti ) have trans-Eurasian ranges, and 3 more ( Bruchus affinis , B. occidentalis and Spermophagus sericeus ) have West-Central Palearctic ranges. Bruchidius marginalis and B. villosus are Western Palearctic species, not known east of Vyatka-Kama region. Kytorhinus pectinicornis , found in the Kungur island forest-steppe, has a Holarctic arcto-alpine habitat of a relict type. 8 species of seed beetles are representatives of the local fauna, developing on wild legumes (Fabaceae), and one species ( Spermophagus sericeus ) on bindweeds (Convolvulaceae). 3 species ( Bruchus pisorum , Acanthoscelides obtectus and Callosobruchus maculatus ) - invaders with different centers of origin, came to the region during an unintentional importation with seed products.

Andiroba oil (Carapa guianensis): Descriptive analysis and applicability

Andiroba oil (Carapa guianensis) is widely used in the Amazon region and elsewhere. Commercial products containing andiroba oil are available for various purposes. In this study, oil obtained using a traditional process was studied. The oil exhibited acceptable quality parameters. The major cations were Ca, K, and Na. Oleic acid was the major fatty acid in the lipid fraction. Hexanal was the major volatile compound. Owing to its composition, we hypothesized that andiroba oil could have insect repellent or antibacterial effects. Its repellent ability against weevils (Acanthoscelides obtectus) was high, although no antimicrobial activity against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, or Salmonella was observed.