Resistencia del frijol al ataque del gorgojo pardo Acanthoscelides obtectus (Say, 1831) (Coleoptera: Chrysomelidae) en la zona Norte de Sinaloa

El frijol es un producto básico en la alimentación de los mexicanos, pero su comercialización y establecimiento es afectado por el gorgojo pardo (A. obtectus), ya que es una plaga grave cuando la semilla está almacenada. En la última década, en Sinaloa, México, se establecieron nuevas variedades de fríjol con características agronómicas valiosas, como la alta productividad y calidad del producto cosechado; sin embargo, es indispensable determinar la resistencia o alta tolerancia de estos cultivares al ataque de este insecto. Debido a esto, se determinó la resistencia de seis cultivares de frijol (Aluyori, Azufrasin, Azufrado Higuera, Azufrado Noroeste, Azufrado Regional 87 y Janasa) cultivados en el centro y norte del estado de Sinaloa, al ataque y daño del gorgojo pardo Acanthoscelides obtectus (Say, 1831). Se compararon seis cultivares con cuatro repeticiones. El cultivar Aluyori presentó mayor resistencia con sólo el 18 % de semilla, escaso número de adultos emergidos (37) y mínima disminución de la capacidad germinativa (2.33 %). Por el contrario, el más susceptible fue Janasa con los siguientes valores: 51.75 %, 131.5 y 24.75 %, respectivamente. Por lo anterior, se recomienda la utilización de Aluyori y Azufrado Higuera para reducir el impacto negativo de la plaga, aunque se recomienda seguir con la experimentación de los materiales contenidos en los bancos de germoplasma para la futura liberación de nuevos cultivares.

DISTRIBUTION AND BIOLOGY OF INVASIVE SPECIES OF BEAN BRUCHID ACANTHOSCELIDES OBTECTUS (INSECTA, COLEOPTERA, BRUCHIDAE)

The review of literary sources on ecology, biology, distribution of bean bruchid ( Acanthoscelides obtectus ) and its main food plant - Phaseolus vulgaris in North and South America; Europe, Africa, Asia, Australia and more details in Russia; the influence of abiotic, biotic and anthropogenic factors on the invasive process, phytosanitary condition of common bean crops in Russia is presented. Some aspects of the invader management are shown. The main stages and areas of cultivation of common bean and invasion of bean bruchid from their primary habitat in South America and in the south of North America are traced; the vectors and reasons causing them are considered. In Russia, the economic importance of bean bruchid has increased since the mid-1980s, which coincided with the climate warming; there was an expansion of its distribution in the eastern and north-western directions. At the last decades of the 20th century, it had penetrated in Smolensk and in the south part of the Tver and the Tomsk regions. With the increase in production of beans in Russia, the lack of systemic protection from bean bruchid and further increase of climate warming will contribute to the extension of its range to the north in the European part of Russia and the Urals to 57-58° N. Lat., where the conditions of the summer period are favorable for development of common bean and bean bruchid. To the east, it may spread to Tyva, Buryatia, the Trans-Baikal territory, the Amur region, the Jewish Autonomous region, and the southern part of the Khabarovsk territory. With the introduction of strict internal quarantine and a system of protection of common bean from this pest, which prevents the spread of infected dry bean, on the contrary, it is possible to reduce the distribution range of the bean bruchid, with its disappearance in the Siberian, Ural districts, Bashkortostan and Tatarstan.

Repellent Activity of Cymbopogon citratus Essential Oil Against Four Major Stored Product Pests: Plodia interpunctella, Sitophilus oryzae, Acanthoscelides obtectus and Tribolium castaneum

Summary The purpose of this study is to assess the repellent activity of lemongrass (Cymbopogon citratus) essential oil (EO), grown in Serbia under greenhouse conditions, against four prevalent stored product pests: Plodia interpunctella (larvae), Sitophilus oryzae, Acanthoscelides obtectus and Tribolium castaneum (adults). The lemongrass EO repellency was tested using filter paper in Petri dishes and a Y-tube olfactometer. According to the repellency index (RI), the lemongrass EO repellency was divided into 5 classes. Prior to biotesting, the chemical characterization of lemongrass EO was performed and the following main compounds were detected: myrcene (31.0%), geranial (30.0%), and neral (23.6%). The C. citratus EO considered was found to exhibit the Class III repellent activity against P. interpunctella larvae only at the highest concentration (namely 0.5%). This is the very first report on the C. citratus EO repellent activity against this pest. The lemongrass EO examined showed strong repellency (Class IV) against S. oryzae (0.2% and 0.5% of EO), A. obtectus (0.1% and 0.2%), and T. castaneum (0.05-0.1%). Moreover, higher lemongrass EO concentrations (0.5%) were found to exhibit extreme repellency (Class V) against A. obtectus and T. castaneum. The results obtained were confirmed in the bioassays performed, indicating the great potential of lemongrass EO as a bio-repellent when applied in higher concentrations to all the insects considered, regardless of the exposure period.

Primer registro de Acanthoscelides obtectus (Coleoptera: Chrysomelidae: Bruchinae) en Senna multiglandulosa (Fabaceae) de la región andina central del Perú

Acanthoscelides obtectus (Say, 1831) (Coleoptera: Chrysomelidae: Bruchinae) es unescarabajo de distribución cosmopolita que ocasiona graves daños a diversas especies de la familia Fabaceae. Este trabajo es el primer reporte de su infestación en arbustos de Senna multiglandulosa (Jacq.) H.S. Irwin & Barneby, 1982 (Fabaceae) en la zona andina central del Perú. Se describe la morfología de los estados biológicos de A. obtectus y las perforaciones que realizaron en legumbres infestadas colectadas en tres lugares del Valle del Mantaro de enero a diciembre 2018. Se midió la longitud total (L) y ancho (A) de los huevos, larvas, pupas y adultos de A. obtectus, así como el diámetro (D) de las perforaciones en vainas y semilla de S. multiglandulosa. Los resultados mostraron diferencias significativas en los tamaños de cada uno de los estadios (p < 0,001) y sus perforaciones en las legumbres (p < 0,001), afectan especialmente las semillas de S. multiglandulosa, por lo cual se constituye en un problema sanitario muy severo en la planta estudiada. Acanthoscelides obtectus (Say, 1831) (Coleoptera: Chrysomelidae: Bruchinae) is a beetle with a cosmopolitan distribution that causes severe damages to diverse species of the Fabaceae family. This is the first report of its infestation on Senna multiglandulosa (Jacq.) H.S. Irwin & Barneby, 1982 (Fabaceae) bushes in the central Andean region of Peru. The morphology of the biological stages of A. obtectus and the perforations they made on infested legumes collected in three sites of Mantaro Valley from January to December 2018 are described. The total length (L) and width (W) of eggs, larvae, pupae, and adults of A. obtectus and the diameter (D) of the perforations on the pods and seeds of S. multiglandulosa were measured. The results showed significant differences in the size of each stage (p < 0.001) and their perforations on legumes (p < 0.001), affecting mainly the seeds of S. multiglandulosa, constituting a severe health problem for the studied plant.

Germination and Agronomic Traits of Phaseolus vulgaris L. Beans Sprayed with Trichoderma Strains and Attacked by Acanthoscelides obtectus

Acanthoscelides obtectus, one of the world’s most important post-harvest pests, attacks wild and cultivated common beans (Phaseolus vulgaris L.). Four Trichoderma strains, Trichoderma arundinaceum IBT 40837 (=Ta37), a wild-type strain producer of trichothecene harzianum A (HA); two transformed strains of Ta37, Ta37-17.139 (Δtri17) and Ta37-23.74 (Δtri23); and T. brevicompactum IBT 40841 (=Tb41), a wild-type strain producer of the trichothecene trichodermin, were evaluated to determine the effect of these compounds on the virulence of A. obtectus and the effect of these strains on the seed’s capacity of germination and on the agronomic traits of the plants grown from these seeds. Treatments of bean seeds with different Trichoderma strains provided varying survival rates in A. obtectus adults, so life survival of insects after Tb41 strain application was reduced to 15 days. Δtri17 and Tb41 strains sprayed on P. vulgaris beans resulted in low weight losses (1.21 and 1.55%, respectively). In spite of the low germination percentage of beans treated with Δtri23 strain (lower than the germination percentages of the rest of the fungal strains applied), this treatment encouraged a greater Wet Weight of Aerial Part of the plants grown from both damaged and undamaged beans. High germination rates of Ta37 and Δtri17 strains (higher than with the rest of treatments), did not turn into a greater Wet Weight Aerial Part and Wet Weight of Root System in the future plants developed. Linear regression between the number of exit holes and the wet weight aerial part on the one hand, and between the number of exit holes and the wet weight root system on the other, showed interaction, so Δtri23 and Tb41 strains behaved differently in comparison to their respective control treatments. The number of exit holes of beans treated with Δtri23 or Tb41 was negatively correlated with both the wet weight aerial part and the wet weight root system in P. vulgaris plants. Δtri23 sprayed on undamaged beans caused the greatest Wet Weight Aerial Part and wet weight root system in plants. Due to the good results obtained by Δtri23 and Tb41 strains in this work, more studies for A. obtectus control, P. vulgaris plant growth and trichothecenes production by these strains should be explored, in order to advance in the knowledge of how these fungi could be used in the field crop, together with the application of management strategies to mitigate risks for farmers and to minimize environmental contamination.

Chemical characterization and insecticidal effect of Moringa oleifera L. seeds extracts on common bean weevil (Acanthoscelides obtectus Say)

Some insects cause high losses of the common bean during storage, namely, <i>Acanthoscelides obtectus</i> Say. Chemical insecticides are commonly used to control insects, but their overuse adversely affects the environment and consumers' health. There is, therefore, the need for an alternative control method. This study was aimed to evaluate the chemical characterization and insecticidal property of <i>Moringa oleifera</i> seed extract on the developmental stages of <i>A. obtectus</i> in stored beans. Three types of <i>M. oleifera</i> seed extracts, namely methanol, ethanol and acetone extracts, were used at doses of 12.5, 25 and 50 µl/ml each. HPLC-MS was used to characterize these extracts. The toxicity of extracts against the adults, the number of eggs and the viability rate of laid or emerged eggs of <i>A. obtectus</i> were evaluated. The results show that <i>M. oleifera</i> seed extract is rich in Hesperidin, Quinic acid, gallic acid, protocatechuic acid, 4-OH benzoic acid, cynaroside, isoquercitrin, cosmosiin, quercitrin, luteolin, naringenin, salicylic acid, Apigenin and Fumaric acid. The acetone extract, from day 2, showed a 100% mortality rate in all doses compared to about only 14% in the control treatment. The number of eggs laid in control (236.67) was higher than the null (0) in acetone treatment at 50 µl/ml. M. oleifera seed extracts contain chemical molecules. They significantly reduced the damage caused by <i>A. obtectus</i> on stored <i>P. vulgaris</i> grains. Therefore, they can be used as an alternative to chemicals for the protection of stored foodstuffs.

How the seed coat affects the mother’s oviposition preference and larval performance in the bean beetle (Acanthoscelides obtectus, Coleoptera: Chrysomelidae, Bruchinae) in leguminous species

Background The host specificity and host range of the dry bean beetle, Acanthoscelides obtectus (Coleoptera: Chrysomelidae, Bruchinae), a seed predator of beans, is poorly known. In addition, the female oviposition preference and larval performance relationship is complicated by the respective importance of seed coat and cotyledon, because, paradoxically, females lay eggs on the basis of stimuli of the seed coat alone, without directly being able to assess the quality of the cotyledon’s suitability for larval development. Conversely, the thickness of seed coat may prevent first instar larvae from entering the seeds, even if cotyledons are suitable for development. Methods The seeds of 62 leguminous species and 75 cultivars and accessions occurring in Hungary were evaluated for preference-performance relations. The preference of female bean beetles for seeds was measured in no-choice egg-laying tests. The ability of first instar larvae to overcome the seed coat as a physical barrier was tested with intact seed coat, while pre-drilled seed coats allowed the larvae to assess the suitability of cotyledon for development. The number of emerging adults was recorded. The thickness of seed coats and the weight of seeds were measured. Nonparametric tests and logistic regression were used for the statistical analyses of data and effect sizes were also calculated. Results Seeds of 18 leguminous species (35% of them Lathyrus) supported larval development to adults if the seed coat was pre-drilled; however, only nine leguminous species supported development to adults if the seed coat was intact. Seed coat thickness beyond a critical threshold of 0.1 mm strongly influenced survival of first instar larvae. There was no overall positive correlation between oviposition preference and larval performance, except for 16 so-called acceptable non-hosts (Kendall’s τ = 0.3088). A. obtectus females also showed an ovipositional hierarchy of legume species even in no-choice tests. Conclusions The results suggest that whereas the use of some acceptable non-host species by the A. obtectus is possible in seed stores, the same is unlikely under outdoor conditions, where the recognition of a diverse set of seed pod-related compounds would be necessary to induce egg-laying.

Ferulago campestris Essential Oil as Active Ingredient in Chitosan Seed-Coating: Chemical Analyses, Allelopathic Effects, and Protective Activity against the Common Bean Pest Acanthoscelides obtectus

Ferulago campestris is an aromatic plant, distributed in Mediterranean Europe, and a source of essential oils (EOs) regarded as promising alternatives to synthetic herbicides and pesticides. F. campestris EO, hydrodistilled and analyzed, was tested for its antigerminative activity and for its effect on radicle elongation, hydrogen peroxide concentration, and lipid peroxidation on four infesting weed species (Papaver rhoeas, Taraxacum campylodes, Poa annua, and Setaria verticillata) and on Phaseolus vulgaris. Its repellent ability was also tested against Acanthoscelides obtectus, a pest commonly affecting P. vulgaris during storage. Moreover, a chitosan coating layer was developed with the addition of F. campestris EO and tested for its toxic and oviposition-deterring effects against A. obtectus. Myrcene, α-pinene, and γ-terpinene were detected as the main compounds in F. campestris EO. The EO demonstrated a selective in vitro antigerminative activity towards the weed species, without affecting the bean seeds. Moreover, the chitosan coating layer exerted a dose-dependent repellent effect against A. obtectus adults, thus effectively protecting the bean seeds, while preserving their germinative ability. To the best of our knowledge, this is the first report on a chitosan–EO coating proposed with the aim of protecting bean seeds for sowing from insect attack.