Revista Colombiana de Entomología

Genetic variation of Bactericera cockerelli Šulc. (Hemiptera: Triozidae) suggests new haplotype in México

2022-04-07T22:53:57-05:00

A new genetic variation and potential new haplotype of Bactericera cockerelli was identified based on the analysis of the mitochondrial region Cytochrome Oxidase subunit I of two populations from greenhouses in Villa Unión, Durango and Saltillo, Coahuila, Mexico. A variation was found in the base 247 of a 500 bp amplified of the mtCOI gene, this change implies the substitution of an adenine (A) to a Guanine (G), this mutation was detected in the insects collect from greenhouses and in their progeny obtained under laboratory conditions. This genetic variant has a great potential to be a new haplotype of B. cockerelli, therefore, it was designated Mexico Haplotype 1 (MXH1) with GenBank accession number KX130767. A total of ten insects from the original collection and then from laboratory cages were evaluated for Lso infection and all tested negative.

Review on the coffee berry borer, Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae), with emphasis on resistance by antibiosis and antixenosis

2022-02-17T16:36:13-05:00

Genetic control as a control method that can be combined with other methods, has been little studied as an economically viable and easy-to-adopt alternative in the case of the coffee berry borer, Hypothenemus hampei (Ferrari), the pest that causes the greatest economic losses to coffee crop in Colombia. Efforts to reduce these economic losses have been mainly focused on the integrated pest management of the pest through cultural, chemical, and biological practices, which have managed to maintain its infestation below 5%, which represents around 7% of coffee production costs. Genetic control can be successfully combined with the other control methods currently being used. The use of resistant varieties increases the efficiency of integrated pest management because it reduces the number of individuals per generation and prolongs their development period. This reduces population growth and keeps insects below economic injury levels. This review presents information on the origin of the coffee berry borer, its dispersal, biology and life cycle, and the economic losses caused by this pest. Emphasis was placed on studies of coffee plant resistance to CBB through antibiosis and antixenosis. In the case of antibiosis, the identification of sources of resistance in the genus Coffea is compiled, as well as the use of Ethiopian introductions of Coffea arabica and accessions of C. liberica from the Colombian Coffee Collection (CCC) as male progenitors for the development of a coffee variety with antibiosis effect against the CBB. In the case of antixenosis, the relevant studies carried out on coffee species and varieties with respect to H. hampei are compiled.

Predatory capacity of the ants Solenopsis picea and Crematogaster crinosa on the coffee berry borer Hypothenemus hampei in the field with an attractant solution

2022-01-30T12:06:55-05:00

The ants present in coffee plantations could be exerting a natural control of the Coffee Berry Borer (CBB), Hypothenemus hampei by preying on the populations of this pest, in fruits abandoned at the end of each harvest. The objective of this research was to evaluate the predatory capacity of two species of ants (Solenopis picea and Crematogaster crinosa) on the CBB with an attractant in field experiments. For each species, ten Experimental Units (EU) containing ten coffee beans infested with CBB were established. The infested grains were placed inside a plastic mesh and hung in trees with that had an ant nest. To attract the ants to the coffee berries, the berries were sprayed with an attractant solution. The same treatments were used with exclusion of ants as absolute control and infested berries without attractant as relative control. The predation rate of S. picea after 24 h was 78.3%, followed by C. crinosa with 34.3%. The attractant bait increased an average of 22% the attraction of ants and predation of biological stages of CBB in each EU, compared to the non-sprayed treatment. The results show that the evaluated ant species reduced the residual populations of H. hampei; S. picea more than C. crinosa.

More than sperm and egg: male, female and environmental factors that influence reproduction of Aedes and Anopheles mosquitoes

2022-03-17T14:03:58-05:00

Reproduction is more than the union of the sperm and the egg, as the successful generation of progeny requires a series of interactions (behavioral, physical, and molecular) between males and females to ensure that a spermatozoon will ultimately fertilize an egg. Thus, reproduction is a complex process in which species- and sex-specific behavioral cues are required for the localization, recognition, and attraction of a sexual partner, and post-insemination interactions between male and female molecules mediate physiological and behavioral changes in females necessary for optimal reproductive output. In this review, we focus on the behavioral and physiological processes required for reproduction in Aedes and Anopheles vector mosquitoes. We highlight recent work that has elucidated the pre-mating behaviors of males and females that lead to a successful copulation, describe the post-mating behavioral and physiological changes observed in females, which primarily serve to facilitate the production of progeny, and discuss the role of sex-specific molecules in mediating the post-mating changes observed in mated Aedes and Anopheles females. Finally, we give an overview of how environmental factors (e.g., larval nutrition or the composition of the microbiome) can influence adult fertility.

Growth and fecundity of Spodoptera frugiperda on native Zea mays and the teosinte Z. luxurians, from Oaxaca, Mexico

2022-02-16T12:30:25-05:00

Resistance to Spodoptera frugiperda (Lepidoptera: Noctuidae) damage has been documented in some Mexican maize races and teosintes. There are approximately 31 races of native maize and three races of teosinte in Oaxaca state, but little is known about their resistance to insect damage. This study compared the development and fecundity of S. frugiperda fed on native maize and the teosinte Zea luxurians, from Oaxaca, Mexico. No significant differences were determined in the development parameters of males and females according to the host plant types, except the pupal weight of males, which was higher on teosinte (0.189 g) than on native maize (0.174 g). Duration from hatching to adult emergence was 28.96 to 30.17 d on native maize and 28.51 to 30.34 d on teosinte. Females emerged before males in both host plant types. The sex ratio was approximately 0.5 for both sexes. Larval weight was higher on teosinte (0.451 to 0.459 g) than on native maize (0.442 to 0.454 g). According to the fecundity parameters, no significant differences in the duration of oviposition, the number of eggs per egg mass, eggs per female, and eggs per host plant types were determined. Fitness Index was positively correlated with the pupal weight of both sexes and the fecundity parameters of S. frugiperda females. Our results demonstrated that larval feeding on native maize and teosinte did not affect the development parameters and fecundity of S. frugiperda. Constitutive defenses in native maize leaves were similar to those of teosinte.

Phytophagous insects associated with avocado orchards (Persea americana Mill.) in the Colombian Caribbean

2022-01-29T18:35:40-05:00

Field studies were carried out in the three main productive nuclei: Montes de María (MM), Sierra Nevada de Santa Marta (SNSM) and Serranía del Perijá (SP), in order to determine the richness and composition of phytophagous insects associated with avocado plantations for the Colombian Caribbean region. The field studies were carried out in 78 farms, covering 26 sampling municipalities. For the capture of phytophagous insects, the manual capture method was used at the plant level, and white light traps and Ecoiapar-type attractive traps were installed at the plot level. With the data obtained, species accumulation curves, Multi Response Permutation Procedure analysis MRPP to determine differences in species composition and analysis of indicator species by productive nucleus were constructed. 42 species of phytophagous insects were identified, grouped in seven orders and 12 families. The most frequent taxonomic groups were termites (Blattodea: Isoptera), scale insects (Hemiptera: Coccomorpha), and branch borers (Coleoptera: Curculionidae). Between 63.4 % and 84.2 % of the expected species richness per productive nucleus was recorded according to the Chao-2 and Jacknife-1 estimators. The highest species richness was obtained in SP (30 species), followed by MM (26 species) and SNSM (16 species). The MRPP analysis detected significant differences in the composition of species between productive nuclei (p ≤ 0.05). The species Nasutitermes sp. for MM, Xylosandrus morigerus for SNSM and Atta sp. for SP they obtained indicator values that differed from those expected at random.

Ideal period for mating females of the predator Podisus fuscescens (Dallas, 1851) (Hemiptera: Pentatomidae)

2022-04-07T23:28:46-05:00

The improvement of techniques for the mass rearing of predators in the laboratory, including the age of mating is important to obtain the largest number of individuals for biological control programs. The purpose of this study was to evaluate the females’ fecundity of the predator Podisus fuscescens (Dallas, 1851) (Hemiptera: Pentatomidae) with different pre-mating periods. The females of this predator were mated immediately after emergence (T1) or with one (T2), two (T3), three (T4), four (T5) or five (T6) days after emergence. The females mated immediately and one day after the emergency (T1 and T2) had fewer egg clusters than those mated after five days (T6). The number of nymphs per female was lower for those mated immediately after the emergence (T1) and with one (T2) or two days (T3). The total number of eggs was lower in females mated one day after emergence (T2) than for those mated after five days (T6). The proportion of hatched eggs was lower in the treatments T1 and T2 than in the T6. The oviposition and longevity of P. fuscescens females were similar between treatments; however, the pre-oviposition period longer in the T1 than T5 and T6. The pos-oviposition period was longer in the T1. Podisus fuscescens females require five days after emergence to mature their reproductive system, which improves their fitness and avoids unnecessary mating.