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Introduction. The asian psyllid (Diaphorina citri Kuwayama) is the main vector of the bacterium Candidatus Liberibacter asiaticus that causes Huanglongbing (HLB) disease in citrus in Panama. Objective. To determine the geographic distribution and host plants of the asian psyllid within the citrus growing areas in Panama. Materials and methods. The study was carried out from June to October 2021 through systematic sampling within 46 localities associated with commercial citrus and home gardens in seven provinces of Panama. In each plant, two new shoots of 10 cm long were bagged with a magic-seal plastic bag to capture the specimens and introduce them into 2 mm plastic vials with 95 % alcohol for later identification. The study variable included the count of the total number of specimens, and the data was analyzed as a percentage. Results. Of the total of 73 collected samples, the presence of the Asian psyllid was confirmed in 21.92 % (16 samples). Its presence was positive in the provinces of Chiriquí, Coclé, Herrera, Panama, and West Panama, at altitudes of 17 to 1080 m.a.s.l. There was no presence of the psyllid in the provinces of Los Santos and Veraguas. Of the 16 samples that were positive, 50 % belonged to the myrtle plant, followed by orange (18.75 %), and creole lemon (12.50 %). Conclusion. The distribution of the asian psyllid vector of HLB in commercial citrus and home gardens in the main citrus growing areas in Panama was presented at different heights above sea level, mainly associated with the presence of the host plants such as myrtle, orange, and creole lemon. Introducción. El psílido asiático (Diaphorina citri Kuwayama) es el principal vector de la bacteria Candidatus Liberibacter asiaticus que causa la enfermedad de Huanglongbing (HLB) en los cítricos en Panamá. Objetivo. Determinar la distribución geográfica y las plantas hospederas del psílido asiático dentro de las zonas citrícolas de Panamá. Materiales y métodos. El estudio se desarrolló de junio a octubre de 2021, a través de un muestreo sistemático dentro de 46 localidades asociadas a cítricos comerciales y huertos familiares en siete provincias de Panamá. En cada planta se procedió a embolsar con una bolsa plástica de cierre mágico dos brotes nuevos de ≈10 cm de largo para capturar los especímenes e introducirlos dentro de viales plásticos de 2 mm con alcohol al 95 % para su posterior identificación. La variable de estudio incluyó el conteo del número total de especímenes y los datos fueron analizados de manera porcentual. Resultados. Del total de 73 muestras colectadas, la presencia del psílido asiático se confirmó en un 21,92 % (dieciséis muestras), resultó positiva su presencia en las provincias de Chiriquí, Coclé, Herrera, Panamá y Panamá Oeste, en alturas desde los 17 hasta 1080 m s. n. m. No hubo presencia del psílido en las provincias de Los Santos y Veraguas. De las dieciséis muestras que resultaron positivas, el 50 % pertenecieron a la planta de mirto, seguida por la naranja (18,75 %) y el limón criollo (12,50 %). Conclusiones. La distribución del psílido asiático vector del HLB en parcelas de cítricos comerciales y de huertos familiares en las principales zonas citrícolas en Panamá, se presentó diferentes alturas sobre el nivel del mar, asociado a la presencia de plantas hospederas como mirto, naranja y limón criollo.

Introduction. Insects are associated with human communities, with positive and negative impacts within each society. This aspect is the basis of the study of insects as a science called entomology, which involves the development of various branches. Due to the social and economic importance of this science in various areas of Panamanian society, a significant development has been achieved during the last forty years. Objective. To determine the branches of entomology applied in Panama during the last four decades. Development. The development of entomology in Panama focused on promoting general, agricultural, veterinary, medical, and forensic entomology through the development of research, teaching, and the establishment of the necessary foundations to promote science. Conclusions. Five branches, including general, agricultural, veterinary, medical, and forensic entomology, constituted the cornerstone and the impetus for the development of entomology as a science for forty years at the service of Panamanian society, justified by social needs related to health, food, and the economic aspects. In recent years topics such as the environment, climate change, and sustainability have also been included. Introducción. Los insectos están asociados a las comunidades humanas con impactos positivos y negativos dentro de cada sociedad. Este aspecto fundamenta el estudio de los insectos como una ciencia llamada entomología, que conlleva el desarrollo de diversas ramas. Debido a la importancia social y económica de esta ciencia en diversos ámbitos de la sociedad panameña, se logró un significativo desarrollo durante los últimos cuarenta años. Objetivo. Determinar las ramas de la entomología aplicadas en Panamá durante las últimas cuatro décadas. Desarrollo. El desarrollo de la entomología en Panamá se enfocó en impulsar la entomología general, agrícola, veterinaria, médica y forense, a través del desarrollo de investigaciones, la enseñanza y el establecimiento de las bases necesarias para impulsar la ciencia. Conclusiones. Cinco ramas que incluyen la entomología general, agrícola, veterinaria, médica y forense constituyeron la piedra angular y el impulso del desarrollo de la entomología como ciencia durante cuarenta años al servicio de la sociedad panameña, justificados en necesidades sociales relacionadas a aspectos de la salud, alimentación y economía. Durante los últimos años también se han incluido temáticas como el medio ambiente, el cambio climático y la sostenibilidad.

Within the genus Diatraea, studies of alternate host plants were mainly conducted on Diatraea saccharalis (Fab.). Such information doesn't exist for Diatraea tabernella Dyar. Therefore, the objective of this study was to determine the alternative host plants of D. tabernella in sugarcane plantations in Panama. From January 2016 to February 2017, a general inventory of alternate host plants was conducted in the sugarcane field and then plants were sampled among the most frequent 9 species found (Poaceae (8) and Cyperaceae (1)) in four areas the sugarcane field (near water source (Z1), within field (Z2), near mangrove (Z3) and field edge (Z4)). The species with the highest % borer infestation during the sugarcane growth period were Sorghum halepense (L.) Pers. (7.2%), Echinochloa colonum (L.) Link (6.4%) and Eleusine indica (L.) Gaertn. (5.8%). During the sugarcane harvest the species with the highest percentage of infested stems were Eleusine indica (L.) Gaertn. (21.6%), Dactyloctenium aegyptium (L.) Beauv. (17.1%) and Cenchrus echinatus (L.) (9.2%). On these host plants, species control measures may be applied to reduce stemborer populations.

Diatraea tabernella Dyar is a key pest of sugarcane in Panama and causes significant crop losses. The objective of this study was to conduct a literature review of the Diatraea genus in Panama, focused mainly on D. tabernella, complemented with the identification of the most important morphological characteristics to determine the species D. tabernella. Reference data were collected from literature about Diatraea genus focused mainly in Panama. Adults, larvae and pupae were collected, preserved and later identified in the laboratory. Of the 41 species of the genus Diatraea reported in the most recent literature, seven are present in Panama, including D. tabernella. The most important morphological characteristics in D. tabernella were the presence of lateral lobes of the tegumen in male genitalia (adult), thoracic dorsal mesothelium (larva) and cephalic horns (pupa). The combination of these characteristics allows the identification of the species.

Sugarcane (Saccharum officinarum) is grown in more than 100 countries worldwide with a total production averaging 170 million tons of sugar that has a profound economic impact on social and governmental issues. In terms of biological constraints there is a complex of diseases and pests that significantly reduce the productivity of sugarcane including stemborers. In Panama, the most important pests that cause losses in sugarcane are lepidopteran stemborers. The aim of this thesis was to study the bioecology of these major pests in Panama and to study different agricultural practices that influence stemborer infestations. To carry out this aim, our thesis has been divided into six overall objectives which constitute 8 different chapters. After presenting the general context (chapter 1), the first objective was to review the results obtained on integrated pest management strategies against the sugarcane borers Diatraea spp. (Lepidoptera: Crambidae), Elasmopalpus lignosellus (Zeller) (Lepidoptera: Pyralidae) and Telchinlicus (Drury) (Lepidoptera: Castniidae) in America that compiles 221 references from 1933 to 2017 (ch apter 2). The second objective was to identify the main sugarcane pest species of Diatraea spp. (Lepidoptera: Crambidae). This research used external morphology and genitalia by comparison with the well know species D. saccharalis and allowed to confirm Diatraea tabernella Dyar as the main stemborer species in Panama (chapter 3). The third objective was to determine the entomofauna associated with stemborers using different trapping systems. A cohort of arthropods was identified as pest species, predators and parasitoids (chapter 4). The fourth objective was to evaluate the use of sentinel prey of Galleria mellonella L. as a trapping technique to identify the key natural enemies that are able to regulate borer population (chapter 5). The experiment was carried out using G. mellonella eggs, larvae and pupae and the results showed that ants (Formicidae) were the most important and effective predators. The fifth objective was to determine the flora associated with stemborers (Weeds present in and around sugarcane fields) (chapter 6). The survey consisted of sampling weeds in four conditions observed in the plantation (Close source of water, within the plantation, between the field and mangrove and at field edges). Six weed species (Poaceae) were identified as host plants of D. tabernella. The sixth objective was to investigate the effect of different agricultural practices on reducing stemborer infestations. As a first step, damage levels and economic impact of stemborer were assessed through a field experiment to determine the effect of different sugarcane varieties on stemborer damage level, the production of sugar components and the impact on sugarcane yield (chapter 7). Our results showed that D. tabernella was able to reduce the quantity and quality of sugar and biomass depending on the type of variety. Second, the effect of silicon and nitrogen doses applied in the field on stemborers infestation were investigated (chapter 8). To carry out this objective we conducted two experiments using an experimental design with 4 replicates. The results showed that the application of high nitrogen levels increased stemborer infestation. The use of silicon significantly reduced infestation. The outcomes of this thesis were the identification of the main species of stemborers, their natural enemies and associated flora, the quantification of their impact on sugarcane and the importance agricultural practices in managing these pests in Panama. The overall results can be used to propose new or refining components to better control stemborers in Panama in a more environnementally friendly way.

The moth borer Diatraea tabernella Dyar (Lepidoptera: Crambidae) feeds on sugarcane causing holes and tunnels in the stalks resulting in yield losses. Damage facilitates the entry of red rot (Colletotrichum falcatum) causing inversion of sucrose in the sugarcane juice. Two types of damage that can be related to sugar loss were assessed and analysed: the percentage of internodes bored in the stalk and the internal damage (= length of borer tunnels). After a preliminary assessment on borer damage in 2012, a new study was conducted in 2016 to thoroughly investigate the impact of D. tabernella not only on cane and sugar yield, but also on stalk parameters (length, diameter, stalk mass, etc). This assessment was conducted on eight varieties and was carried out on three samples (replicates) of five stalks per variety grouped in five damage levels (0, 1, 2,3 and 4 internodes bored). The results indicated that stalk mass, fiber and sugar yield were significantly affected by the stalk borer. Sugar yield decreased up to 2.56 t of sugar per hectare, with damage level 3 similar to the yield with no damage (level 0). Internodes of cultivars E0709, Na56-42, SP01-2050 and SP81-3250 were less damaged at the two-internode category and had lower sugar losses. There was a positive correlation between internodes bored and loss of sugar per hectare (y = 0.5789x + 0.3504, R2 = 0.9046) with a range from 12.9% with damage level 1 to 26.47% loss with damage level 4.

In Panama, lepidopteran stem borers Diatraea saccharalis (Fabricius) (Crambidae), Telchin licus (Durry) (Castniidae) and Elasmopalpus lignosellus (Zeller) (Pyralidae) are the most important pests for the sugarcane industry. The objective of this preliminary study was to start an inventory and assessment of the fauna (invertebrates and vertebrates) and flora associated with the sugarcane agrosystem and to investigate the damage and impact of stemborers. In addition, we also conduct preliminary tests with the synthetic pheromones of D. saccharalis and E. lignosellus, the main species.. The observations were conducted in 2015 during 4 months, from january to april in CALESA Sugar Company, Panama. Borer damage was assessed on a total of 2100 stalks taken from one single field. On average, infestation level was 23.5% of stalk damaged with 1.4% of internodes bored The larval parasitism rate on D. saccharalis was 23.53%, comprising &RWHVLD ÀDYLSHV (5.88%), Lixophaga diatraeae (5.88%) and Billaea claripalpis (11.76%). The majority of the holes and tunnels from this borer species were located between internodes 13 and 20 in the middle section of the stalk. Nine species of vertebrates (birds, bats, lizards mainly) and 16 orders, 57 families and 66 species of arthropods were recorded. A list of pests and predators such as spiders, ants and other groups are being identified or confirmed. D. saccharalis pheromones did not attract this species in trapping experiments, despite the use of different trap designs whereas as Elasmopalpus synthetic pheromone attracted adults. Further tests will be conducted on a longer period. (Texte integral)