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Aphis gossypii; Cylas formicarius elegantulus; Ipomoea batatas; Myzus persicae; Pseudoplusia includens; entomology; epidemiology; herbivores; ingestion; pest management; phloem; population dynamics; sap; summer; sweet potatoes; viruses; weight gain
Abstract:
... Aboveground and belowground herbivory can alter host quality and trophic interactions. However, little research has explored the impacts of belowground herbivory on plant virus epidemiology. To understand this interaction in sweetpotato, Ipomoea batatas L. (Lam), we studied the impact of herbivory by sweetpotato weevil, Cylas formicarius elegantulus (Summers), to storage roots on vector herbivore, ...
Cylas formicarius elegantulus; Lepidoptera; Metarhizium anisopliae; Metarhizium robertsii; biological control; conidia; economic feasibility; fungi; genes; integrated pest management; virulence; Cuba
Abstract:
... AIMS: Entomopathogenic Metarhizium fungi are widely recognized for their biological control potential. In Cuba, several fungus‐based bio‐insecticides have been developed and are produced as part of integrated pest management (IPM) programmes for economically relevant agricultural pests. Screening of fungal isolates from the INISAV strain collection was used for the development of bio‐insecticides ...
... An eradication project against the sweetpotato weevil, Cylas formicarius (Fabricius) (Coleoptera: Brentidae), one of the most important pests of sweet potato in the world, was initiated in Oct. 2007 on Tsuken Island, Okinawa Prefecture, Japan. The sterile insect technique (SIT) and male annihilation technique (MAT) were employed as the main control measures to suppress and ultimately eradicate wil ...
... The sweet potato weevil (Cylas formicarius) is an important pest in the growing and storage of sweet potatoes. It is a common pest in the sweet potato production areas of southern China, causing serious harm to the development of the sweet potato industry. For the existing cultivars in China and abroad, there is no sweet potato variety with complete resistance to the sweet potato weevil. Thus, und ...
... Sweetpotato weevil, Cylas formicarius elegantulus (Summers) (Coleoptera: Brentidae), an in-field and storage pest of sweetpotato, is the primary insect constraint to sweetpotato production in tropical and subtropical regions. Feeding by adult and larval sweetpotato weevil induces terpenes, rendering storage roots unmarketable. To reduce storage root damage and sweetpotato weevil populations, the p ...
... Pest control component integration of sweetpotato weevil (Cylas formicarius Fab.) (Coleoptera: Curculionidae). Sweetpotato weevil Cylas formicarius Fabricius is major obstacle in increasing of sweet potato production in various countries. Tuber damage due to C. formicarius causes yield loss up to 80%. This study aims to examine the integration control of C. formicarius in entisol, each control com ...
... Females of many animals mate multiple times during their lives (i.e., polyandry). The period between matings (mating interval) is called the refractory period (RP). In the West Indian sweet potato weevil (Euscepes postfasciatus), males use the ejaculate to induce the RP in females to prevent re-mating. By measuring the RP, a large variation of 1–49 days was observed. This variation may be due to t ...
... Sweetpotato weevil (SPW) pest management is challenging because the pest target is sub-terranean, so the application of pesticides is impractical and usually ineffective. Host plant resistance and the genetic transformation of sweetpotatoes to produce entomotoxic Bt proteins offer potential for environmentally benign pest control. Resistance can be conferred by naturally occurring hydroxycinnamic ...
... The yield and insect resistance of 12 sweetpotato (Ipomoea batatas) clones grown in two different production systems (organic black plastic mulch and conventional bare ground) were evaluated in 2016 and 2017 in coastal South Carolina. Significant differences in total storage root yield, marketable storage root yield, U.S. No. 1 storage root yield, and percent of U.S. No. 1 storage roots in all tri ...
... BACKGROUND: The sweet potato weevil, Cylas formicarius, is the most serious pest of sweet potato worldwide. The molecular mechanism of sex pheromone recognition in C. formicarius has not been reported. Odorant‐binding proteins (OBPs) play a critical role in selectively binding and transporting pheromones or other odors to the surface of olfactory receptor neurons through the aqueous sensillar lymp ...
... Five isolates of Metarhizium sp. were evaluated for their pathogenicity against the spider mite (Tetranychus truncatus Ehara) (Acari: Tetranychidae) and Metarhizium sp. BCC 4849 resulted in the highest mortality (82%) on the 5th day post-inoculation (DPI). Subsequent insect bioassay data indicated similar high virulence against five other insects: African red mites (Eutetranychus africanus Tucker) ...
... We examined the genetic variation in the sequences of cytochrome c oxidase subunit I gene (DNA barcode region) and some other regions of mitochondrial DNA of sweet potato weevil, Cylas formicarius (Fabricius, 1798) (Coleoptera: Brentidae), and West Indian sweet potato weevil, Euscepes postfasciatus (Fairmaire, 1849) (Coleoptera: Curculionidae), in Japan. In the DNA barcode region of C. formicarius ...
Victor Jaoko; Clauvis Nji Tizi Taning; Simon Backx; Pierfrancesco Motti; Jackson Mulatya; Jan Vandenabeele; Titus Magomere; Florence Olubayo; Sven Mangelinckx; Stefaan P. O. Werbrouck; Guy Smagghe
... The African sweet potato weevil, Cylas puncticollis, and fall armyworm, Spodoptera frugiperda, are insect pests of economic importance that have a negative impact on sweet potato and maize production, respectively. In this study, we aimed to evaluate the potential of Melia volkensii extracts to protect sweet potato and maize plants against damage by both insect pests. We evaluated extracts from th ...
... Multiple mating by females increases both the risk and intensity of sperm competition for males. The ability to temporarily or permanently inhibit female receptivity to further mating represents a highly adaptive strategy to reduce the risk of sperm competition. Males of the West Indian sweet potato weevil Euscepes postfasciatus (Fairmaire) (Coleoptera: Curculionidae) and the seed bug Togo hemipte ...
... Increased sweetpotato utilization has become an important breeding objective recently, with much emphasis on the development of non-sweet sweetpotatoes for income and food security in Ghana. The objective of this study was to evaluate 26 elite non-sweet and less sweet sweetpotato genotypes with regard to their release as commercial varieties using mother–baby trial. The 26 sweetpotato genotypes we ...
... Artificial diets have been employed for the mass-rearing of numerous insects because of their ease of use and standardized quality. An ability to store artificial diets under nonrefrigerated conditions over the long term could improve the efficacy of mass-rearing systems considerably. However, it remains largely unknown how long artificial diets can be stored at such temperatures without any adver ...
... Most terrestrial animals live in natural atmospheric conditions, but some are also adapted to low oxygen (hypoxic) or high‐carbon dioxide (hypercapnic) conditions, such as in social insect nests, soil, caves, wood, and decaying material. Although it is possible that individuals adapt their behaviour to the environmental condition of their habitats, mating behaviour under ecologically possible rang ...
... Sweet potato weevil (Cylas punticollis Boheman) is a serious pest throughout sub-Saharan Africa. A study to evaluate 51 sweet potato genotypes for their tolerance to the weevil was conducted in a controlled experiment of no-choice arena. Genotype Tainung was the most susceptible to C. puncticollis. Genotypes Obugi and 5 Nyandere were the most tolerant to C. puncticollis. Many of the genotypes that ...
... BACKGROUND: Chemosensory proteins (CSPs) play important roles in chemical communication, but their precise physiological functions are still unclear. Cylas formicarius is the most serious pest attacking sweet potato around the world. At present, there is no effective way to control this pest. RESULTS: Our results showed that CforCSP1, 5 and 6 genes were highly expressed in the antennae of both sex ...
... Tonic immobility (TI) is a well-known anti-predator strategy adopted by diverse preys. Numerous studies on the cost–benefit involve in TI have been reported. Although, some studies have reported the effect of mating behavior on TI, few studies highlight the phases of mate search. In the present study, we investigated the relationship between mate search and TI behavior in the sweetpotato weevil (S ...
Cylas formicarius elegantulus; Hawaii; cluster analysis; databases; entomology; microsatellite repeats; population genetics; sweet potatoes; transcriptome; Georgia; South Carolina
Abstract:
... To conduct population genetics analyses on sweetpotato weevils (Cylas formicarius elegantulus) collected from three populations in the United States, microsatellite loci were developed from sweetpotato weevil transcriptome sequences obtained from a publicly available database. Nineteen of 27 microsatellite loci tested were usable for population analyses. Sweetpotato weevil individuals from Georgia ...
... Biotic constraints cause major crop losses and, hence, food insecurity in sub-Saharan Africa. This study documented the popularity, production constraints, pests and diseases, farmers’ perceptions on the severity of biotic constraints and the impact of related crop losses on household food security for the key root, tuber and banana (RTB) crops (cassava, potato, sweetpotato and banana). Farm ...
... This study provides a protocol for the isolation of high-quality DNA from sweetpotato weevils (Cylas formicarius elegantulus (Summers)) collected from pheromone-baited aerial funnel traps. This study was based on our discovery that a 2-wk collection interval of sweetpotato weevils from pheromone traps did not permit isolation of intact high-quality genomic DNA. To test the effect of collection met ...
... RNA interference (RNAi) refers to the process of suppression of gene expression in eukaryotes, which has a great potential for the control of pest and diseases. Unfortunately, the efficacy of this technology is limited or at best variable in some insects. In the African sweet potato weevil (SPW) Cylas puncticollis, a devastating pest that affects the sweet potato production in Sub-Saharan Africa ( ...
Cylas formicarius elegantulus; Euscepes; Ipomoea batatas; entomology; genetic variation; geographical distribution; mitochondria; population structure; probability; sweet potatoes; India; South America
Abstract:
... Cylas formicarius F. and Euscepes batatae Waterhouse are the most damaging sweet potato insect pests globally. Both weevils are thought to have invaded the Pacific alongside the movement of sweet potato (Ipomoea batatas (L.) Lam. Convolvulaceae), with C. formicarius having originated in India and E. batatae in Central or South America. Here we compare the genetic relationships between populations ...
... Okinawan sweet potato, Ipomoea batatas, is an important food staple and export crop for the Island of Hawaii. Cylas formicarius elegantulus, sweet potato weevil, is a major quarantine pest that causes severe destruction to the crop. Root malformation and a bitter taste occur when larvae feed and tunnel within the storage root. Off-grade roots are often left in the field after harvest and serve as ...
... BACKGROUND: Sweet potato weevil, Cylas formicarius (Fabricius) attacks stems and storage roots of sweet potato, Ipomoea batatas, and is a major pest of this globally significant crop. To minimize the immigration of weevils into sweet potato fields from nearby donor habitat, we assessed scope for a barrier plant approach. Here, we report a novel, two‐stage, multiple choice olfactometer method to sc ...
... Twelve sweetpotato (Ipomoea batatas var. batatas) accessions/cultivars/landraces (entries) were evaluated for yield, resistance to pests, and quality in five field trials planted at Pepe`ekeo, Hawai‘i Island, and replicated over time with blocks planted on May and Oct. 2014, Feb. and July 2015, and Jan. 2016. Plots were harvested at 4.5 to 6 months after planting. In the first two field trials, lo ...
... Saputro TB, Prayogo Y, Rohman FL, Alami NH. 2019. The virulence improvement of Beauveria bassiana in infecting Cylas formicarius modulated by various chitin based compounds. Biodiversitas 20: 2486-2493. Sweet potato (Ipomoea batatas L.) is one of alternative carbohydrate source with an important role in food production, animal feed industries, and as raw materials for other derivatives. However, s ...
... Sweet potato (Ipomoea batatas (L.) Lam. is an important food crop adaptable to a broad range of agro-ecological conditions. The knowledge of the performance of the available varieties under a specific ecological condition is important to improve the production. A field experiment was carried out at the University of Ghana farm during the major and minor rainy seasons of 2015 to determine the yield ...
Cylas formicarius elegantulus; Euscepes postfasciatus; adults; body size; eggs; females; mass rearing; progeny; sterile insect technique
Abstract:
... It is necessary to establish an economical mass-rearing system for the West Indian sweet potato weevil Euscepes postfasciatus (Fairmaire) so that large numbers can be created for use in the sterile insect technique (SIT) to control wild infestations. Both the quality of offspring and the number of adult weevils produced are important. As an adult female with a dry weight of less than 1.4 mg has an ...
... Adult female and male sweetpotato weevils, Cylas formicarius (Fabricius), have repertories of at least 19 and 21 behavior patterns, respectively. These are described and named, including eight self-grooming patterns. Consistent with the species' slight sexual dimorphism, few behavior patterns are peculiar to one sex. The sequence of self-grooming movements is analyzed for each sex. Comparative ass ...
... Gamma radiation from isotopic sources has been used in sterile insect technique (SIT) programs worldwide, but it might be difficult to continue using these sources in future SIT programs because of social issues. Therefore, an alternative sterilization source to gamma rays, such as X-rays, needs to be developed. The physical properties of radiation are different between gamma rays and X-rays: for ...
... Biological assays were carried out to determine the effectiveness of powders of three locally available plants, Dennettia tripetala (G. Backer), Xylopia aethiopica (A. Rich) and Aframomum melegueta (K. Schum), for the control of Cylas puncticollis a sweet potato weevil. Powders of the leaves and fruits of each plant were separately applied at concentrations of 1, 3 and 5% (w/w for powders) for bio ...
... Sweetpotato is an important staple food crop in Hawai'i, both for local consumption and export. Insect damage, especially from weevils, is a major production constraint of sweetpotato in the state of Hawai'i. Rough sweetpotato weevil, Blosyrus asellus (Olivier) is an invasive pest recently detected in the Hawaiian Islands. The immature stages of the weevil gouge shallow grooves on surfaces of stor ...
... Sweetpotato weevil (SPW), Cylas formicarius elegantulus (Summers), is the most damaging root-feeding insect of sweetpotato, Ipomoea batatas (L.) Poir., worldwide. Larval feeding on storage roots reduces yield and induces terpene production, rendering roots inedible. Selection of sweetpotato cultivars with resistance to insect pests has been carried out for over a century but no high yielding, prod ...
... Quarantine pests in plants can be a serious agricultural problem; many eradication programs using area-wide control measures have been implemented worldwide to combat this threat. Surveillance measures using sex pheromone (in general, male-attractant) traps are also widely implemented for rapid control and eradication of invasive pests. If initial pest colonization can be determined based on tempo ...
... A potent male attractant of sweetpotato weevil helps in monitoring and control of sweetpotato weevil in many production areas around the world. At present, it has not been used in Malaysia. Cost of the components of a trapping system is a major constraint in the adoption of male lure‐baited trapping by growers in Malaysia. Seven field trapping experiments were conducted from February 2013 to Novem ...
... The sterile insect technique (SIT) has been used for the control or eradication of target insect pests. To successfully apply SIT, it is very important to clarify the effect of irradiation on male reproduction in the target pest, because their mating and spermiogenesis abilities affect the success of eradication program. The sweetpotato weevil, Cylas formicarius (Fabricius) (Coleoptera: Brentidae) ...
Curculionidae; Cylas formicarius elegantulus; analysis of variance; climate; environmental factors; genotype; pests; rain; selection index; sweet potatoes; temperature
Abstract:
... Despite the ability of sweetpotato to grow in marginal areas, large differential genotypic responses have been reported under varying environmental conditions. Differences in pest and disease pressure contribute significantly to inconsistencies in performance of genotypes in various environments. Using a randomized complete block design, eight sweetpotato genotypes were evaluated in one location s ...
... The development of sweetpotato [Ipomoea batatas (L.) Lam] germplasm with resistance to sweetpotato weevil (SPW) requires an understanding of the biochemical and genetic mechanisms of resistance to optimize crop resistance. The African sweetpotato landrace, ‘New Kawogo’, was reported to be moderately resistant to two species of SPW, Cylas puncticollis and Cylas brunneus. Resistance has been associa ...
... This study estimated the amount of loss in storage roots caused by various levels of damage caused by sweetpotato weevils (Cylas spp). Seven varieties of sweetpotato (Ipomoea batatas L. (Lam)) were evaluated in three production sites in northern Ghana for two years (2014 and 2015). Yield data for each experimental plot were collected. A regression analysis was carried out using the generalized lin ...
Beauveria bassiana; Cylas formicarius elegantulus; Hyphomycetes; control methods; cultivars; dipping; experimental design; insects; leaves; pest management; pests; planting; roots; spraying; sweet potatoes; South Africa
Abstract:
... Sweet potato weevils (Cylas puncticollis and C. formicarius) are notorious pests of sweet potato and cause severe losses in marketable yield. The study tested the use of Beauveria bassiana ((Balsamo) Vuillemin) (Deuteromycota: Hyphomycetes) for controlling sweet potato weevils. An experiment was conducted using four treatments: 1) dipping sweet potato cuttings in solution of 1 g/litre B. bassiana ...
... BACKGROUND: RNA interference (RNAi) technology can potentially serve as a suitable strategy to control the African sweet potato weevil Cylas puncticollis (SPW), which is a critical pest in sub‐Saharan Africa. Important prerequisites are required to use RNAi in pest control, such as the presence of an efficient RNAi response and the identification of suitable target genes. RESULTS: Here we evaluate ...
... Soil-dwelling pests are generally poorly documented in East Africa due to their cryptic nature, which complicates monitoring, so the aim of this review is to compile and elucidate the current soil insect pest and management situation in this region. Fifty-five (55) soil insect pests are reported from across East Africa, and twenty (36%) and seventeen (30%) species of Scarabaeidae and Termitidae, r ...
... Metarhizium anisopliae has a wide range of coleopteran hosts, including weevils. Some susceptible insects are known to modify their behavior to prevent infection, typically detecting virulent strains by olfaction, and avoiding physical contact with sources of infection. Laboratory olfactometer assays were conducted on the sweetpotato weevil Cylas formicarius to test the hypothesis that insects wou ...
Curculionidae; Cylas formicarius elegantulus; Metarhizium anisopliae; adults; conidia; eggs; fecundity; females; host plants; long term effects; males; maternal exposure; mortality; pests; plant tissues; reproductive success; sweet potatoes; Papua New Guinea
Abstract:
... Cylas formicarius is a major pest of sweetpotato in Papua New Guinea. In this study, the chronic effects of infection with Metarhizium anisopliae strain QS155 in adult C. formicarius were investigated. Female fecundity was significantly reduced in treatments where females were infected directly and maintained in pairs with either infected or uninfected males, and to a statistically equivalent leve ...
... In southern Japan, sweet potato weevils Euscepes postfasciatus (Fairmaire) are being eradicated using the sterile insect technique because of their damaging effects on sweet potato crops. However, the effect of irradiation on the dispersal and survival of this species needs to be evaluated. We observed the dispersal of normal and irradiated weevils for 21 days after their release in a sweet potato ...
... The relationship between sperm production, insemination rate, and sperm transfer were studied in the sweet potato weevil, Cylas formicarius. Older adult males retained more sperm in the testes-seminal vesicle complex (TSC) and thus more was ejaculated into females at first mating. Number of matings per day for males was relatively constant across different ages, and frequent mating resulted in a r ...
... Sweetpotato has been the subject of little research worldwide compared with other major crop staples, and this is especially so for less developed countries where sweetpotato is critical for food security. This review synthesises information on plant protection issues that affect smallholder sweetpotato farmers in less developed countries to identify major issues and suggest research priorities. T ...
... The sweet potato weevil (SPW), Cylas formicarius, is a serious pest of sweet potato in Australia and Papua New Guinea. Ten strains of Metarhizium sp. isolated from Australian soil samples were evaluated for their growth characteristics and screened for virulence to adult SPW under laboratory conditions. All isolates except QD62 (48.6%) had moderate to high germination (66–97%), and all took 2 to 4 ...
... Sweet potato weevil (Cylas formicarius) is the most serious pest of sweet potato (Ipomoea batatas), not only in the Virgin Islands but also throughout the Caribbean. It causes damage in the field to leaves, stems and tuberous roots. Our objective was to evaluate harvest date and weevil damage in 18 sweet potato cultivars. Twelve sweet potato cultivars were from in vitro virus-free material and six ...
... The life stages of Cylas formicarius in sweet potato tubers were assessed during first and second generations. In first generation, the highest egg period was recorded in Co-3 (White) (5.50 days). The lowest larval period was recorded in Kanjangad (24.16 days) while highest pupal period was recorded in Kanaka (Red) (7.56 days) and the total life cycle period in days was highest in Co-3 (White) (42 ...
... Assessment of the impact of transgenic crops on non-target organisms (NTO) is a prerequisite to their release into the target environment for commercial use. Transgenic sweetpotato varieties expressing Cry proteins (Bt sweetpotato) are under development to provide effective protection against sweetpotato weevils (Coleoptera) which cause severe economic losses in sub-Saharan Africa. Like any other ...
Curculionidae; Cylas formicarius elegantulus; bacteria; biotechnology; entomopathogenic fungi; financial economics; food crops; genomics; integrated pest management; intercropping; mechanism of action; pesticides; pests; plantations; sex pheromones; subtropics; sweet potatoes
Abstract:
... Sweet potato is an important food crop that is grown widely in tropical and subtropical regions. Sweet potato weevil is the most disastrous pest affecting sweet potato plantations, causing millions of dollars losses annually. An effective integrated pest management (IPM) method will help to prevent economic losses, and it is crucial to understand the factors that contribute to weevil infestation a ...
Curculionidae; Cylas formicarius elegantulus; animals; beneficial organisms; biological control agents; females; foraging; male sterility; males; mass rearing; mating behavior; mating competitiveness; pests; spermatozoa; sterile insect technique; summer; tropics; Japan
Abstract:
... Selection for genetic adaptation might occur whenever an animal colony is maintained in the laboratory. The laboratory adaptation of behavior such as foraging, dispersal ability, and mating competitiveness often causes difficulties in the maintenance of biological control agents and other beneficial organisms used in procedures such as the sterile insect technique (SIT). Sweet potato weevil, Cylas ...
Curculionidae; Cylas formicarius elegantulus; flight; mass rearing; sex pheromones; sterile insect technique
Abstract:
... For ensuring the effectiveness of sterile insect technique (SIT) programmes, maintaining the reproductive competitiveness and dispersal ability of mass‐reared sterile males is essential. Inadvertent selection is an important genetic process that frequently occurs during mass rearing to produce sterile males. We investigated the effect of mass‐rearing conditions on the responsiveness to sex pheromo ...
... The sweetpotato weevil Cylas formicarius (F.) (Coleoptera: Brentidae) is one of the most serious insects causing damage to sweetpotatoes in the world. Small populations of these insects can cause severe damage to tubers of the crop. Without proper and effective control, weevil populations are likely to cause a huge or complete loss of sweetpotato production in sweetpotato growing areas. Consequent ...
... Entomopathogenic nematodes (EPN) are well-known as biological control agents and are found to have associated bacteria which can produce a wide range of bioactive secondary metabolites. We report herewith isolation of six proline containing cyclic dipeptides cyclo(D-Pro-L-Leu), cyclo(L-Pro-L-Met), cyclo(D-Pro-L-Phe), cyclo(L-Pro-L-Phe), cyclo(L-Pro-L-Tyr) and cyclo(L-Pro-D-Tyr) from ethyl acetate ...
... The sweetpotato weevil, Cylas formicarius (F.) (Coleoptera: Brentidae), is one of the most important pests of sweet potatoes in the world. With free trade between the United States and the U.S.-controlled Mariana Islands, C. formicarius has spread along with this commodity. Because of the cryptic nature of the larvae and nocturnal activity of the adults, and the cancellation of long-residual pesti ...
... The preferences of the West Indian sweet potato weevil, Euscepes postfasciatus (Fairmaire), to tubers of sweet potato, Ipomoea batatas (L.), for food and for oviposition were evaluated, and correlated to sweet potato's resistance to immatures. Adults (parent) were released in a plastic box containing tubers of sweet potato cultivars and maintained for 5 d, after which the adults on each tuber were ...
Cylas formicarius elegantulus; canopy; chemical control; color; larvae; natural enemies; pests; quarantine; red light; sex pheromones; sweet potatoes; trapping; traps; tubers; vines
Abstract:
... The sweetpotato weevil, Cylas formicarius (Fabricius) (Coleoptera: Brentidae), is the most serious pest of sweetpotato around the world, damaging sweetpotatoes in the field and in storage, as well as being a quarantine pest. Because the larval period is spent within vines or tubers, and the adults are nocturnal, chemical control frequently is not effective. In addition, there are few natural enemi ...
... Fifty-nine sweetpotato cultivars, including 16 heirlooms, 11 near-heirlooms (developed in the 1960s and 1970s), 19 cultivars from the 1980s, and 13 modern varieties (since 1990), were evaluated for resistance to soil insects in field experiments during 2010–2011 at the U.S. Department of Agriculture-Agriculture Research Service, U.S. Vegetable Laboratory (USDA-ARS, USVL), Charleston, SC. These exp ...
... Host-plant resistance could be a useful tool for managing the weevils Cylas puncticollis and C. brunneus, which are major insect pests of sweetpotato in Africa. There is currently little information on existing resistance mechanisms against Cylas spp. in African cultivars, except where lower levels of weevil damage were attributed to escape due to deep rooting and reduced soil cracking, limiting t ...
... African sweetpotato weevils (SPW), Cylas puncticollis and C. brunneus, pose a major threat to sweetpotato, which plays a vital role in food security and income generation for both the urban and rural poor in Sub-Saharan Africa (SSA). SPW can limit sweetpotato production causing total crop loss. Control methods such as integrated pest management and breeding have not succeeded satisfactorily in cur ...
... When there is an inbreeding depression, mating with a kin individual is generally considered maladaptive behaviour. However, in some conditions, the inclusive fitness benefits from inbreeding may outweigh the costs of inbreeding depression, and thus, inbreeding tolerance is often adaptive. Inbreeding depression and the effect of relatedness on mating behaviour in the West Indian sweet potato weevi ...
... Inadvertent selection is an important genetic process that frequently occurs during laboratory culture. The mass-reared strain of the sweet potato weevil Cylas formicarius exhibits stronger inbreeding depression than the wild strain does. When inbreeding depression occurs in a population, mating with a close relative is often considered maladaptive; however, in some contexts, the inclusive fitness ...
... The sterile insect technique (SIT) is widely used for suppressing or eradicating target pest insect populations. In the eradication programs using the SIT, a large number of sterile insects are marked and released in the field. In Japan, Cylas formicarius (F.) group (Coleoptera: Brentidae) weevils are marked with a fluorescent powder dye to monitor the progress of such programs. However, this moni ...
Cylas formicarius elegantulus; adsorption; males; mass rearing; mating behavior; sex pheromones; sterile insect technique
Abstract:
... In sterile insect technique (SIT) programs, the released sterile males are important for their effectiveness. The use of sex pheromones to collect males is economical; however, pre-exposure to sex pheromones may affect male mating behavior, and would thus reduce the effectiveness of the SIT programs. Males exposed to sex pheromone may become attractive to other males due to pheromone adsorption on ...
... The sterile insect technique (SIT), based on the principles of population and behavioral ecology, is widely used to suppress or eradicate target pest insect populations. The effectiveness of SIT depends on the ability of released sterile males to mate with and inseminate wild females; however, the use of gamma radiation to induce sterility negatively affects both somatic cells as well as reproduct ...
... A survey to document indigenous knowledge associated with sweetpotato production was conducted in Chitipa, Karonga and Mzimba in the North and Mulanje, Phalombe, Chikhwawa and Nsanje Districts of Malawi in 2003. The study aimed to better understand the knowledge associated with farmers’ varieties for potential use in the development of improved and acceptable varieties. In total, 268 varieties wer ...
... Because life-history theory predicts that risky behaviours such as mating should increase as life expectancy decreases, predatory avoidance is expected to decrease with age. However, this prediction has not been examined. In the present study, the effect of age on death-feigning behaviour, a form of predatory avoidance behaviour in the sweetpotato weevil Cylas formicarius (Summers) (Coleoptera: Br ...
... Persistent mating attempts by males (sexual harassment) are frequently observed among animals. For females, resisting persistent males can be costly because vigorous resistance increases both energy expenditure and the possibility of injury. Although one tactic for coping with male harassment is to cease resistance and mate with the persistent partner, the females of several species are able to pr ...
... The sterile insect technique (SIT) is widely used to suppress or eradicate target pest insect populations. Although the effectiveness of SIT depends on the ability of released sterile males to mate with and inseminate wild females, the use of gamma radiation to induce sterility negatively impacts reproductive cells as well as somatic cells. Consequently, sterilization by irradiation drastically di ...
... Inadvertent selection is an important genetic process that frequently occurs during laboratory culture and maintenance of biological control agents and other beneficial organisms used in procedures such as the sterile insect technique (SIT). We investigated effects of mass rearing and inbreeding depression on life history traits (number of progeny emerging from host plants, body weight, developmen ...
... The sterile insect technique (SIT) is widely used for suppressing or eradicating target pest insect populations. The effectiveness of SIT depends on the ability of released sterile males to mate with and inseminate wild females. Irradiation is the effective manner to sterilize mass-reared insects. The negative impacts of this procedure are not limited to damage on reproductive cells. Gamma-radiati ...
... The virulence of eight isolates of Metarhizium anisopliae and four isolates of Beauveria bassiana (Ascomycota: Hypocreales) to adult Cylas puncticollis (Coleoptera: Curculionidae) was tested in the laboratory. Insects were sprayed with a standard concentration of 1.0 x 10⁷ conidia mL⁻¹ using Burgerjon's spray tower. All the isolates tested were pathogenic to C. puncticollis. Mortality varied betwe ...
Monte Carlo method; simulation models; Cylas formicarius elegantulus; sweet potatoes; food transport; introduced species; imports; Ipomoea batatas; quantitative risk assessment; risk reduction; probabilistic models; Southeastern United States
Abstract:
... We assessed the risk associated with introduction of sweet potato weevil, Cylas formicarius elegantulus (Summers) (Coleoptera: Brentidae), from infested areas to noninfested areas via shipment of sweet potato, Ipomoea batatas (L.), roots within the southern United States. Our study quantifies the effectiveness of risk mitigation procedures of sweet potatoes before shipment in relation to introduct ...
... A new species of braconid, Bracon yasudai Maeto et Uesato sp. nov., is described here from the south-west islands of Japan. It is a solitary idiobiont ectoparasitoid of the larvae of the West Indian sweetpotato weevil, Euscepes postfasciatus (Curculionidae), and the sweetpotato weevil, Cylas formicarius (Brentidae), both feeding on Ipomoea batatas (L.) (Convolvulaceae). The percentage parasitism o ...
... We used the mark-and-recapture method in the field to test the effect of gamma radiation on the dispersal ability of the male sweetpotato weevil, Cylas formicarius elegantulus (Summers) (Coleoptera: Brentidae), a serious sweetpotato pest in Japan. To evaluate the dispersal ability of male sweetpotato weevil, we released 27,218 males (13,302 males irradiated with a dose of 200 Gy and 13,916 nonirra ...
Cylas formicarius elegantulus; sex pheromones; chemical composition; synthesis; antennae; sensilla; electrophysiology; electroantennography; stereoisomers; olfactometry; mating behavior; pheromone traps; Cuba
Abstract:
... The sex pheromone of feral sweet potato weevils Cylas formicarius elegantulus from Cuba was found, via solid-phase microextraction analysis, to be identical to (Z)-3-dodecenyl (E)-2-butenoate, a previously reported compound. Females emitted 20 pg pheromone d-1. In scanning electron microscopy studies carried out on the male antenna, we identified several types of sensilla: sensilla trichoidea of t ...
Hyptis; chemical composition; sesquiterpenoids; insect pests; Cylas formicarius elegantulus; oviposition; Rhipicephalus microplus; insecticidal properties; essential oils; insect growth regulators; acaricidal properties; mass spectrometry; gas chromatography; insect reproduction; shoots
Abstract:
... The chemical composition of the essential oil obtained by hydrodistillation from the aerial parts of Hyptis verticillata Jacq. was elucidated by a combination of GC and GC-MS analyses. The oil was dominated by the sesquiterpenoids cadina-4,10(15)-dien-3-one (15.1%) (1) and aromadendr-1(10)-en-9-one (squamulosone) (30.7%) (2). The oil exhibited chemosterilant activities against the cattle tick, Boo ...
acetates; Cylas formicarius elegantulus; sweet potatoes; sex pheromones; urban areas; tubers; integrated pest management; rural areas; health foods; kairomones; sales; starch; food quality; pickles; wholesale marketing; research programs; Fusarium oxysporum; pests; Rhizopus oryzae; periderm; markets; Curculionidae; farmers; syrups; soft drinks; germplasm conservation; India
Abstract:
... Sweetpotato is grown in India in 0.11 million hectares, with an annual production of 1.0 million tons and productivity of 8.8 t ha-1. The major constraints in the production and processing front for sweet potato in India are inconsistency in tuberization, seasonal instability in yield and lack of (i) weevil-resistant sweet potato varieties, (ii) adequate technological innovations on stable marketa ...
Curculionidae; Cylas formicarius elegantulus; alternative hosts; biological control; breeding; chemical control; chemical ecology; cultivars; cultural control; larvae; monitoring; mulching; pests; sanitation; sex pheromones; sweet potatoes
Abstract:
... The sweetpotato weevil (Cylas formicarius) is the major pest of sweetpotato worldwide. Yield losses of up to 80% can occur. A range of control strategies are available. Cultural control methods, including sanitation, mulching and the destruction of alternative hosts, are widely practised. However, chemical control is constrained by the internal feeding of the larvae, while biological control strat ...
Cylas formicarius elegantulus; Ipomoea batatas; pest resistance; nitrogen fertilizers; leaves; nitrogen content; feeding behavior; oviposition; mortality; roots; periderm; glycosides; caffeic acid; genotype; application rate; chemical constituents of plants; Louisiana
Abstract:
... The effects of nitrogen fertilizer on sweet potato, Ipomoea batatas (L.) Poir., resistance to the sweetpotato weevil, Cylas formicarius elegantulus (Summers), was studied. Adult weevil feeding and oviposition preference, larval survival, and pupal weight were used as measures of sweet potato resistance. Sweet potato resin glycosides and caffeic acid concentrations in the periderm tissue of storage ...
... An ionizing irradiation quarantine treatment of 165 Gy was approved by the California Department of Agriculture against sweetpotato weevil, Cylas formicarius elegantulus (Summers), infesting sweetpotatoes from Florida. The first commercial shipment was made in May, 2000. At >or= 400 Gy, 'Picadito' white-fleshed sweetpotatoes sometimes showed noticeable discoloration of cooked flesh. Therefore, the ...
... The biology of two African sweetpotato weevil species, Cylas puncticollis and C. brunneus (Fabricius) (Coleoptera: Apionidae), was studied in laboratory experiments carried out at 27 ± 1°C, 45 ± 5% RH, and a 12 h photophase. Cylas puncticollis females lived longer than C. brunneus (141 ± 10 and 92±12 days respectively), developed faster (egg to adult 20–28 days, and 32–41 days respectively) and ha ...
... Dispersal distance of the male sweetpotato weevil, Cylas formicarius elegantulus (Summers), was estimated in the field. Two experiments were conducted. In experiment 1, release and capture were replicated 3 times from September to October in the same locality consisting mainly of sweet potato fields. Approximately 8,000 marked males were released and approximately 30% of released males were captur ...
... An alternative synthesis of (Z)-3-dodecen-l-yl (E)-2-butenoate without use of carcinogenic ethylene oxide and HMPA is described. By coupling of the tetrahydropyranyl (THP) ether of 3-butyn-1-ol with 1-bromooctane with sodamide in liquid ammonia, 12-(2-tetrahydropyranyloxy)-9-dodecyne was obtained; subsequent hydrolysis and semihydrogenation afforded (Z)-3-dodecen-1-ol. The alcohol was then reacted ...
Ipomoea batatas; tubers; extraction; chemical composition; Cylas formicarius elegantulus; triterpene acids; oviposition attractants; chemical constituents of plants
Abstract:
... A methylene chloride extract from the surface of sweet potato storage roots (cultivar Centennial) was fractionated on silicic acid and eluted with hexane, 1:3 methylene chloride-hexane, and 1:1 methylene chloride-hexane. The 1:3 methylene chloride-hexane fraction yielded compound I: > 96% purity, the most dominant compound present; mp 238-239.5 degrees C; IR, 1730, 1250 cm-1. The mass spectrum of ...
... The entomopathogenic nematodes Heterorhabditisbacteriophora Poinar (=H. heliothidis Khan, Brooks, & Hirschmann) (HP88 strain) andSteinernema (=Neoaplectana) carpocapsae Weiser (All and G-13 strains) were evaluated asbiological control agents of the sweetpotato weevil, Cylas formicarius elegantulus (Summers). InPetri dish bioassays, all three strains were pathogenic to larvae and pupae of C. f.eleg ...
... Sampling programs for the sweet potato weevil, Cylas formicarius elegantulus (Summers), were developed for 0.2-ha and 0.4-ha plots of sweetpotato (Ipomoea batatas (L.) Lam.). Taylor's power law was fit to data on spatialdispersion of sweetpotato weevil, and results were used to develop relationships between numbers ofsample units and levels of precision for selected mean densities per plant. Resul ...
Cylas formicarius elegantulus; sex pheromones; insect control; mark-recapture studies
Abstract:
... Studies were conducted to determine the effects of sex pheromone dosage and lure age on movement of male sweetpotato weevils (SPW), Cylas formicarius elegantulus (Summers), using mark-release-recapture techniques. SPW trap counts from various downwind distances were compared for dosages ranging from 0.01 to 10.0 lag and lure ages ranging from fresh (O days old) to 64 days old. The percentages of m ...
... An improved laboratory bioassay was used to characterize an oviposition stimulant from the surface of sweet potato Ipomoea batatas (L.) Lam. storage roots for the sweetpotato weevil, Cylas formicarius elegantulus (Summers). Filter paper discs impregnated with a methylene chloride surface extract of sweet potato storage roots induced significantly (p < 0.05) higher oviposition on root cores than th ...
... A bioassay was developed to quantify the feeding of adult sweet potato weevils, Cylas formicarius elegantulus (Summers) (Coleoptera; Curculionidae) on the foliage of four cultivars (Centennial, Jewel, Resisto and Regal) of sweet potato (Ipomoea batatas (L.) Lam.) (Convolvulaceae). Weevils fed along the leaf veins, preferring the lower to the upper leaf surface. Males and females had similar levels ...
... Cores from sweet potato (Ipomoea batatas L.) storage roots, with either the outer periderm or inner core exposed, were presented to female sweet potato weevils, Cylas formicarius elegantulus (Summers) (Coleoptera: Curculionidae) in cage preference tests. Tests with weevils of different ages showed that feeding was constant 21 to 76 days after emergence, while oviposition showed a slight peak betwe ...
... Endoproteinase activity was confined to luminal fluid from anterior and posterior ventricular regions of midguts of larvae of the sweetpotato weevil, Cylas formicarius elegantulus (Summers). Aminopeptidase was found in luminal fluid (18%) but was primarily associated with insoluble fractions from cells of the posterior ventriculus (82%). Depending on substrate, carboxypeptidase activity was about ...