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1.
The effects of Beauveria bassiana strains on coffee berry borers (CBB), which emerge from infested berries left on soil, and its impact on the infestation of coffee berries on tree branches were evaluated at two Experimental Stations (Naranjal-Caldas and Paraguaicito-Quindio) in the Colombian coffee zone. Using a completely randomized design with 10 repetitions, 50 coffee berries artificially infested with CBB were placed on the base of a coffee tree. Four treatments including B. bassiana strain Bb9205, a mixture of Cenicafé strains (Bb9001, Bb9024 and Bb9119), a commercial formulation of B. bassiana and a control (water) were sprayed with 1×109 conidia per tree. After 30 days, all fungal strains lowered the infestation levels of the coffee berries on the trees at both locations. The mixture of Cenicafé strains decreased the tree infestation between 50 and 30% at both locations. In the berries dissected from each treated tree, insect mortality was about 40% at both locations compared to 15% in the control. B. bassiana strains also decreased the insect population inside the newly infested berries on the trees by 55–75%. The mixture of Cenicafé strains was the most effective for decreasing insect populations. B. bassiana significantly decreased CBB populations that emerged from fallen, infested, coffee berries and reduced future insect generations.  相似文献   

2.
The virulence of four fungal isolates (three Beauveria bassiana and one Metarhizium anisopliae ) against adult female coffee berry borers (CBB) was investigated. The most virulent isolate from initial bioassays, B. bassiana LPP1, with a LT 50 of 3.4 days, was further investigated by application to berries prior to infestation and to berries already infested with CBB. At the highest concentration applied to berries (1 ×10 7 conidia mL -1 ), CBB mortality was 83% (berries inoculated prior to infestation) and 62% (berries inoculated after infestation).  相似文献   

3.
The effect of three strains of the fungus Beauveria bassiana (Balsamo) Vuillemin and two strains of Metarhizium anisopliae (Metschnikoff) Sorokin upon the coffee berry borer, Hypothenemus hampei (Ferrari), was studied in three coffee farms at different altitudes (450-1,100 m above sea level) in Soconusco, Chiapas, Mexico. The maximum average percentage mycosis varied according to altitude. At 450 m asl (El Rincon) mycosis was 14.3% for B. bassiana and 6.3% for M. anisopliae; at 880 m asl (Santa Anita) mycosis was 40.6% for B. bassiana and 12.6% for M. anisopliae, and at 1,100 m asl (Alpujarras) 33.9% for B. bassiana and 22. 1% for M. anisopliae. The effect of fungal mycosis through time was not significant (P > 0.01) in any of the farms, but there was a significant difference between the strains of the fungus (P < 0.01); the best strains being Bb25 and Ma4 at the lower altitude, Bb26 and Ma4 for the middle altitude and Bb26 and Ma4 at the higher altitude. Environmental factors such as temperature, relative humidity and rain were not correlated with the percentage mycosis caused by B. bassiana and M. anisopliae. However, in the case of B. bassiana there was a significant, positive correlation (P < 0.01) between the infestation levels of the pest and the mycosis response of the entomopathogen.  相似文献   

4.
The coffee berry borer (CBB), Hypothenemus hampei Ferrari (Coleoptera: Curculionidae: Scolytinae), is one of the major insect pests of coffee worldwide. The present study was designed to assess the level of infestation of coffee berries at different developmental stages across different altitudes and coffee management systems. The experiment was carried out at three locations in southwestern Ethiopia under two coffee management systems and four coffee berry development stages with three replications. Results of the study showed significantly highest proportion of damaged berries (37.5%), number of holes per berry (10.88) and number of adult CBB per berry (7.55) on dried leftover berries at low-altitude study sites. On the other hand, the lowest mean percent damaged berries, number of holes per berry and number of adults were recorded at mid- and high-altitude study sites. The study also showed that, CBB caused significantly highest damage in plantation coffee management system than garden coffee. Results of this study highlight proper harvesting at red ripe stage in order to minimise incidence of CBB. It is also important to design integrated management strategies to mitigate CBB damage especially in lowland plantation coffee production systems.  相似文献   

5.
A phylogenetic epidemiological study of Beauveria bassiana s.l. was conducted for African and Neotropical pathogens of the coffee berry borer (CBB), Hypothenemus hampei, based on inferences from two nuclear intergenic regions, EFutr and Bloc. CBB pathogens were distributed among four terminal clades, however, the majority of African and Neotropical isolates cluster in a well-supported monophyletic group, informally designated AFNEO_1. Although the relationship between African and Neotropical AFNEO_1 is unresolved, the majority of alleles detected were exclusive to either the African or the Neotropical populations. These fixed genetic differences suggest that their disjunction predates the world trade in coffee. Neotropical AFNEO_1 have a broad host range and CBB pathogens are intermixed phylogenetically with isolates from diverse indigenous insects. Several Neotropical AFNEO_1 isolates were isolated from coffee plants as epiphytes or endophytes, thus plants themselves may potentially serve as reservoirs of pathogens against their insect pests. Topological incongruence between the EFutr and Bloc phylogenies of Neotropical AFNEO_1 may signify that individuals within this population are recombining.  相似文献   

6.
Mortality of the coffee berry borer was studied under controlled laboratory conditions in Tapachula, Mexico. For adult female borers subjected to a range of relative humidities (RH) without food at 25°C, the longest mean survival time (20 days) was obtained at 93.5% RH. Adult borer survival was also studied at a range of temperatures for a fixed relative humidity (93.5% RH); at 20°C mean survival time was 28 days. Fecundity and mortality of borer stages in berries was studied for a range of humidities at 25°C. Maximum fecundity was obtained at 90 and 93.5% RH. Immature stages were ejected from the berry at 84% RH and above, which is interpreted as a form of brood hygiene.  相似文献   

7.
The coffee berry borer, Hypothenemus hampei, is the most damaging insect pest of coffee worldwide. Like males in other species in the genus, male coffee berry borers have a lower number of facets in the compound eyes than females. The rudimentary eyes in male coffee berry borers could be an evolutionary response to their cryptic life habit, whereby they are born inside a coffee berry and never leave the berry. The main objective of the study was to determine if the differences in the number of facets translates into differences in visual acuity. We used low-temperature scanning electron microscopy to visualize and quantify the number of facets in the compound eyes. There was a significantly lower (p<0.0001) number of facets in males (19.1±4.10) than in females (127.5±3.88). To assess visual acuity, we conducted optomotor response experiments, which indicate that females respond to movement, while males did not respond under the conditions tested. The coffee berry borer is an example of an insect whereby disuse of an organ has led to a rudimentary compound eye. This is the first study that has experimentally tested responses to movement in bark beetles.  相似文献   

8.
Coffee berry borer (Hypothenemus hampei Ferrari), the most damaging insect pest of coffee worldwide, was first detected on Hawaii Island in 2010. Poorly managed, abandoned and feral coffee sites on the island have since been thought to harbour coffee berry borer (CBB) populations, which then negatively impact neighbouring coffee farms. In the present study, we sought to quantify CBB abundance in these sites, which vary in management intensity and vegetation structure and diversity. We collected data on trap catch as a measure of CBB flight activity, fruit production and fruit infestation by CBB in eight well-managed farms and sites that were either poorly managed, abandoned or feral (wild) coffee. Sites were sampled bi-weekly over a period of 2 years from 2016 to 2017. We found that CBB flight activity was significantly higher in poorly managed sites relative to abandoned and feral sites, but was not significantly different from well-managed sites. Coffee production in well-managed farms was significantly higher than in abandoned and feral sites, but was not significantly different from poorly managed farms. CBB infestation in poorly managed sites was significantly higher than that observed in well-managed, abandoned and feral sites. We estimated an average load of 11–25 CBB per branch at poorly managed sites, compared to 3–9 per branch at well-managed sites, 1–16 per branch at abandoned sites and 1–3 per branch at feral sites. Our findings suggest that poorly managed sites should be prioritized for implementation of CBB control measures as part of a landscape-level integrated pest management (IPM) programme.  相似文献   

9.
The coffee berry borer (CBB) is the most prevalent pest of coffee plantations. Within the Coffea genus, C. arabica is susceptible to CBB and C. liberica shows a lower susceptibility. Two EST libraries were constructed from the total RNA of C. arabica and C. liberica fruits artificially infested with CBBs for 24 h. Using 6000 clones sequenced per library, a unigene database was generated, obtaining 3634 singletons and 1454 contigs. For each contig, the proportion of sequences present in both species was determined and a differential gene expression between the species was detected. C. arabica displayed a higher relative expression of proteins involved in general stress responses, whereas C. liberica showed the induction of a higher number of insect defense proteins. In order to validate the results, quantifications through real-time PCR were done. A hevein-like protein, an isoprene synthase, a salicylic acid carboxyl methyltransferase and a patatin-like protein gene were highly upregulated in C. liberica at 24 and/or 48 h after insect infestation compared to C. arabica. The identification of metabolic pathways induced by this pest insect provides tools to take advantage of the genetic resources available for the control of CBB.  相似文献   

10.
1 Management of vegetational diversity in agroecosystems is a potentially regulating factor of pest population dynamics and may affect developmental stages in different ways.
2 We investigated the population dynamics of red spider mites, coffee leaf miners, and coffee berry borers in three management types of coffee agroforests: increasing plant diversity from a few shade tree species (simple-shade agroforests), intermediate-shade tree species (complex-shade agroforests) to high-shade tree species (abandoned coffee agroforests) in Ecuador. Furthermore, we studied how changes in agroforestry management affect population stage structure of each coffee pest.
3 Our results show that agroforestry management affected seasonal patterns of coffee pests in that higher densities of red spider mites were observed from August to December, coffee leaf miners from December to February, and coffee berry borers from May to July. Moreover, specific developmental stages of red spider mites, coffee leaf miners, and coffee berry borers differed in their responses to agroforestry management. During all stages, red spider mite reached higher densities in simple-shade agroforests compared with complex-shade and abandoned agroforests. Meanwhile, coffee leaf miner densities decreased from simple-shade to complex-shade and abandoned agroforests, but only for larvae, not pupae. Similarly, only coffee berry borer adults (but not eggs, larvae and pupae) demonstrated a response to agroforestry management. Environmental variables characterizing each agroforestry type proved to be important drivers of pest population densities in the field.
4 We emphasize the importance of considering seasonal differences and population structure while investigating arthropod responses to different habitat types because responses change with time and developmental stages.  相似文献   

11.
《Journal of Asia》2023,26(4):102118
Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae), a coffee berry borer (CBB), is a serious pest of coffee fruits and causes economic losses in the coffee industry. With the concerns of chemical control, an alternative eco-friendly management strategy such as microbial control has emerged as the times require. Herein, a total of thirty-three fungi were isolated from CBB cadavers. Two entomopathogenic fungal isolates, NCHU-271 and NCHU-272, which showed fast insect-killing activity, were subjected to molecular identification and named “Beauveria bassiana-NCHU-271” (Bb-NCHU-271) and “Beauveria bassiana -NCHU-272” (Bb-NCHU-272). Moreover, a virulence test of Bb-NCHU-271 and Bb-NCHU-272 against CBBs was also performed. Both Bb-NCHU-271 and Bb-NCHU-272 caused 100% mortality at 8 days post inoculation (d.p.i.) and a LT50 of Bb-NCHU-271 by spraying 108 conidia/ml was less than Bb-NCHU-272. Therefore, histological evidence of Bb-NCHU-271 infected CBBs was provided to proven the infection process of B. bassiana in CBBs. Furthermore, an infestation test was performed to evaluate the differences in CBB control efficacy between the treatments of “Borers exposed to EPF first” or “Berries exposed to EPF first”. The results revealed that the “Borers exposed to EPF first” of Bb-NCHU-272 caused significantly lower survival rates and higher mycosis rates than those of Bb-NCHU-271. Only slight control effects of Bb-NCHU-271 and Bb-NCHU-272 were also observed in the “Berries exposed to EPF” treatment. In conclusion, Bb-NCHU-271 and −272 showed controlling ability to the CBBs either before or after CBB infestation into coffee berries, while application of EPFs before the CBBs bored into coffee fruits could enhance the control effect.  相似文献   

12.
Coffee berry borer (CBB) is the Worlds most devastating coffee pest causing an estimated US$500 million worth of losses annually through damage and control costs. Beauveria bassiana and Metarhizium anisopliae have been employed to control this pest but their low virulence (slow kill and large inoculums) is an important factor constraining their use. M. anisopliae (AaIT-Ma549) has been modified to express the scorpion toxin (AaIT) in insect hemolymph and this greatly increased pathogenicity against Manduca sexta and Aedes aegypti. Here, we demonstrate that AaIT-Ma549 was also dramatically more virulent against CBB, and we provide a much more comprehensive analysis of infection processes and post-mortality development than in the previous research. We evaluated several spore concentrations (101 through 107 spores/ml) of both the wild type and recombinant strain. At concentrations of 101, 102 and 103 spores/ml, the recombinant strain significantly increased mortality of CBB by 32.2%, 56.6% and 24.6%, respectively. The medial lethal concentration (LC50) was reduced 15.7-fold and the average survival time (AST) was reduced by 20.1% to 2.98 ± 0.1 days with 107 spores/ml. This is the first occasion that an entomopathogenic fungus has been found to kill CBB in less than 3 days. However, AaIT-Ma549 produces significantly fewer spores on cadavers than the parental strain.  相似文献   

13.
Abstract  The use of Beauveria bassiana proparations for control of coffee stem borers, Xylotrechus quardripes Chevr. and Acalolepta cervinus (Hope), as tested in the laboratory and field conditions. The results show that each instar of coffee stem borers could be infected and killed successfully when being inoculated or contacted with B. bassiana . The control efficacy under indoor cultivation conditions exceeded 90% within 15 days. Jamming drilled hole with fungal mud resulted in the accumulative mortality and corrected mortality of > 90% within 20 days. In the field, three methods, jamming drilled holes with bamboo sticker, bamboo sticker with fungal mud, and fungal mud only, were employed, and each led to the control effect of > 90% within 20 days. However, spraying suspensions and dusting powder of B. bassiana ww insignificant. The yield of fresh coffee fruits in biological control area waa 125.7 kg/0.067 ha greater than that of control area when being harvested in February. Compared the cost of microbial control with that of chemical control, B. bassiana proved to be a profitable, effective, and safe biocontrol agent against coffee stem-borer.  相似文献   

14.
Coffee berries are known to release several volatile organic compounds, among which is the spiroacetal, conophthorin, an attractant for the coffee berry borer Hypothenemus hampei. Elucidating the effects of other spiroacetals released by coffee berries is critical to understanding their chemo-ecological roles in the host discrimination and colonization process of the coffee berry borer, and also for their potential use in the management of this pest. Here, we show that the coffee berry spiroacetals frontalin and 1,6-dioxaspiro [4.5] decane (referred thereafter as brocain), are also used as semiochemicals by the coffee berry borer for host colonization. Bioassays and chemical analyses showed that crowding coffee berry borers from 2 to 6 females per berry, reduced borer fecundity, which appeared to correlate with a decrease in the emission rates of conophthorin and frontalin over time. In contrast, the level of brocain did not vary significantly between borer- uninfested and infested berries. Brocain was attractive at lower doses, but repellent at higher doses while frontalin alone or in a blend was critical for avoidance. Field assays with a commercial attractant comprising a mixture of ethanol and methanol (1∶1), combined with frontalin, confirmed the repellent effect of this compound by disrupting capture rates of H. hampei females by 77% in a coffee plantation. Overall, our results suggest that the levels of frontalin and conophthorin released by coffee berries determine the host colonization behaviour of H. hampei, possibly through a ‘push-pull’ system, whereby frontalin acts as the ‘push’ (repellent) and conophthorin acting as the ‘pull’ (attractant). Furthermore, our results reveal the potential use of frontalin as a repellent for management of this coffee pest.  相似文献   

15.
Coffee is a globally important crop that is subject to numerous pest problems, many of which are partially controlled by predatory ants. Yet several studies have proposed that these ecosystem services may be reduced where agricultural systems are more intensively managed. Here we investigate the predatory ability of twig-nesting ants on the main pest of coffee, the coffee berry borer (Hypothenemus hampei) under different management systems in southwest Chiapas, Mexico. We conducted both laboratory and field experiments to examine which twig-nesting ant species, if any, can prey on free-living borers or can remove borers embedded in coffee fruits and whether the effects of the twig-nesting ant community differ with habitat type. Results indicate that several species of twig-nesting ants are effective predators of both free-living borers and those embedded in coffee fruits. In the lab, Pseudomyrmex ejectus, Pseudomyrmex simplex, and Pseudomyrmex PSW-53 effectively removed free-living and embedded borers. In the field, abundance, but not diversity, of twig-nesting ant colonies was influenced by shade management techniques, with the highest colony abundance present in the sites where shade trees were recently pruned. However, borer removal rates in the field were significant only in the shadiest site, but not in more intensively managed sites. This study provides evidence that twig-nesting ants can act as predators of the coffee berry borer and that the presence of twig-nesting ants may not be strongly linked to shade management intensity, as has been suggested for other arthropod predators of the borer.  相似文献   

16.
Colombia is one of the world's largest producers of coffee [Coffea arabica L. (Rubiaceae)]. The coffee berry borer (CBB), Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae), is the main pest of coffee. This insect is controlled through an integrated pest management program that includes cultural, biological, and chemical control strategies. Despite research seeking CBB attractants and repellents, these potential management tools have not been successfully incorporated into control programs. This work proposes the use of plant functional diversity for CBB management, for which a number of plants related to coffee and weeds were selected. CBB preference to these plants was determined by olfactometry and volatile compounds emitted by them were identified. Field trials were performed to test CBB preference under field conditions. These trials determined the olfactory preference of CBB to coffee berries accompanied by material of the plants Crotalaria micans Link (Fabaceae), Lantana camara L. (Verbenaceae), Nicotiana tabacum L. (Solanaceae), Artemisia vulgaris L., Calendula officinalis L., Stevia rebaudiana (Bertoni) Bertoni, and Emilia sonchifolia (L.) DC. (all four Asteraceae). Under laboratory conditions N. tabacum, L. camara, and C. officinalis were identified as repellents for CBB in olfactometer assays, whereas E. sonchifolia functioned as attractant. Controlled field trials corroborated CBB repellency of N. tabacum and L. camara; both release volatile sesquiterpenes. Selected candidate attractants included E. sonchifolia plants, for showing attraction in the laboratory. The potential use of these plants in agroecological management of coffee plantations is discussed.  相似文献   

17.
在昆明动物研究所和云南省思茅市大开河咖啡场进行了咖啡天牛的白僵菌防治试验。室内和田间试验结果表明,只要接触到白僵菌的各龄咖啡天牛,均可被感染致死;室内培养条件下的虫体一般在第15天左右致死率可达90%以上,室内木段堵孔到第20天累计死亡率达90%以上,室外插竹签,菌签插孔和菌泥堵孔法在第20天防治效也可达90%以上,手撒菌粉和喷菌液法虽有一定防治作用,但效果不显著,产量测定结果显示,生物防治区咖啡鲜果每0.067公顷(1/15ha.)比对照区高125.7kg;与几种常用杀虫剂防治费用比较认为,白僵菌是一种经济、安全的生物杀虫剂。  相似文献   

18.
Species’ functional traits are an important part of the ecological complexity that determines the provisioning of ecosystem services. In biological pest control, predator response to pest density variation is a dynamic trait that impacts the provision of this service in agroecosystems. When pest populations fluctuate, farmers relying on biocontrol services need to know how natural enemies respond to these changes. Here we test the effect of variation in coffee berry borer (CBB) density on the biocontrol efficiency of a keystone ant species (Azteca sericeasur) in a coffee agroecosystem. We performed exclosure experiments to measure the infestation rate of CBB released on coffee branches in the presence and absence of ants at four different CBB density levels. We measured infestation rate as the number of CBB bored into fruits after 24 hours, quantified biocontrol efficiency (BCE) as the proportion of infesting CBB removed by ants, and estimated functional response from ant attack rates, measured as the difference in CBB infestation between branches. Infestation rates of CBB on branches with ants were significantly lower (71%-82%) than on those without ants across all density levels. Additionally, biocontrol efficiency was generally high and did not significantly vary across pest density treatments. Furthermore, ant attack rates increased linearly with increasing CBB density, suggesting a Type I functional response. These results demonstrate that ants can provide robust biological control of CBB, despite variation in pest density, and that the response of predators to pest density variation is an important factor in the provision of biocontrol services. Considering how natural enemies respond to changes in pest densities will allow for more accurate biocontrol predictions and better-informed management of this ecosystem service in agroecosystems.  相似文献   

19.
The coffee berry borer (CBB), Hypothenemus hampei (Ferrari), is the most important insect pest of coffee worldwide. In this study, we used headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry to sample and identify volatile compounds from Robusta coffee berries, Coffea canephora Pierre ex Froehner, infested with CBB and with mechanical damage. Furthermore, we evaluated the behavioral responses of the CBB and two of its parasitoids, Prorops nasuta Waterstone and Phymastichus coffea LaSalle, to three selected coffee volatile compounds in a Y-tube olfactometer. We found in the effluvia of red coffee berry compounds not previously reported for this coffee species. Our results show that Robusta coffee berries release induced volatiles either by insect herbivory or by mechanical damage. Small amount of butyl acetate, unknown compound 2, α-longipinene, longiborneol and longiborneol acetate are produced only in infested coffee berries fruits. Quantitatively, nine compounds account for the difference between healthy berries, infested, or mechanically damaged berries. Trans-ocimene, 4,8-dimethyl-3,7-nonadien-2-ol, α-copaene and kaurene increased amount levels in infested berries, while amount of methyl salicylate and linalool increased in mechanically damaged coffee berries. The olfactometric bioassays showed that CBB females and its two parasitoids were attracted to methyl salicylate. In addition, H. hampei and P. nasuta were attracted to linalool, and P. nasuta and P. coffea were attracted to trans-ocimene.  相似文献   

20.
Several parasitoids of African origin have been introduced to coffee producing areas of the Americas and Asia as biological control agents of the coffee berry borer (CBB) Hypothenemus hampei (Coleoptera: Curculionidae). These parasitoids have become established in the field but their effect on the CBB has been limited. A two-year field study in Western Kenya has found Prorops nasuta (Hymenoptera: Bethylidae) to be the predominant parasitoid emerging from CBB-infested coffee berries collected on coffee trees or from the ground. P. nasuta comprises more than 75% of the total natural enemies collected. The density of P. nasuta was 90% higher in the berries collected from the ground than from the trees. Its hyperparasitoid, Aphanogmus sp. (Hymenoptera: Ceraphronidae), also emerged from both type of berries. Across the two seasons, the average P. nasuta density per berry was 18–35 times higher than that of Aphanogmus sp. Throughout the two years sampled, significantly higher numbers of P. nasuta and Aphanogmus sp. occurred between February and March, which coincides with the beginning of the rainy season. Higher numbers of live CBB females were recorded in berries collected from the trees. Nevertheless, mortality of adult CBB was considerably higher from January to March and started to decrease from April onwards. The possibly negative effects of cultural control practices in Latin America which include the removal of berries fallen to the ground on biological control of CBB are discussed, and the use of screened collection devices for these berries which would permit the release of parasitoids but prevent escape of the pest is proposed.  相似文献   

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