RESUMO
The fall armyworm (FAW) Spodoptera frugiperda (J. E. Smith) has become a global devastating pest because of its broad dispersal capacity and the high crop damages. At present, research on FAW infestations of crops in the DR Congo remains undocumented. Here, FAW infestations in two agro-ecological zones (Kabare and Ruzizi Plain) were compared in South-Kivu Province. Surveys were carried out during the early 2018 and late 2019 crop seasons to assess the impact of FAW on maize crops. In each agro-ecological zone, 50 fields were selected for investigation. A total of hundred (100) fields were assessed in the 2018 crop season. During the 2019 crop season, the same fields were investigated. The two zones had very different bioclimatic characteristics. FAW attacks were more pronounced under conditions of relatively high temperatures with high evapotranspiration, which occurred in the Ruzizi Plain and late 2019 season. In comparison, Kabare territory and the early 2018 season were characterized by heavy rainfall. The incidence, level of leaf damage, and density of FAW larvae varied significantly with season and agro-ecological zone. The Ruzizi Plain had the highest incidence (60 ± 30%), level of leaf damage and larval density (28.5 ± 19.3). The late 2019 season had the highest incidence (70 ± 20%) as well as the larval density (27.8 ± 19.2). Total annual number of FAW generations was 5.64 and 3.36 in the Ruzizi Plain and Kabare territory, respectively. In conclusion, FAW infestation represents a major problem for agricultural production due to the climatic conditions in the study region.
Assuntos
Herbivoria , Estações do Ano , Spodoptera , Zea mays , Animais , Produtos Agrícolas , República Democrática do Congo , Larva , Densidade DemográficaRESUMO
In this century, climate change is one of the major problems affecting livestock productivity. This study aimed at evaluating the effect of body coat color pattern and sex on heat regulation and heat stress tolerance in indigenous goat breeds exposed to solar radiation. In the experiment, 4 bucks and 4 does (8 to 9 months age) with black, white, grey and browncoat color were selected and exposed to solar radiation during 12 days during the summer period. Water and feed were served add libitum. The consumption were measured daily at 17:00 for each animal. Rectal temperature (RT) and rate pulse (PR) were measured three-time (7:00, 12:00, and 17:00) every day on each animal during the experimental period. At the end of the experiment, blood samples were collected from the jugular vein and immediately delivered to the lab to determinebiochemical (serum protein: albumin and globulin), and hematological parameters. Exposing goats to temperature variation affected the physiological, hematological as well as biochemical parameters in all subjects. The female with a black body coat color was mostly affected. The heat stress induced an increase of RT and PR, an increase in waterconsumption while depression in food intake was observed. Blood platelets, hematocrits, red cell distribution, white blood cell and albumin were damaged in goats with black coat color compared to goats with white coat color. These variations in physiological, hematological and biochemical parameters in female black goat could affect its productive and reproductive performances in high-temperature environments.
Assuntos
Masculino , Feminino , Animais , Aquecimento Global , Cabras/fisiologia , Comportamento Sexual Animal/efeitos da radiação , Mudança Climática/economiaRESUMO
In this century, climate change is one of the major problems affecting livestock productivity. This study aimed at evaluating the effect of body coat color pattern and sex on heat regulation and heat stress tolerance in indigenous goat breeds exposed to solar radiation. In the experiment, 4 bucks and 4 does (8 to 9 months age) with black, white, grey and browncoat color were selected and exposed to solar radiation during 12 days during the summer period. Water and feed were served add libitum. The consumption were measured daily at 17:00 for each animal. Rectal temperature (RT) and rate pulse (PR) were measured three-time (7:00, 12:00, and 17:00) every day on each animal during the experimental period. At the end of the experiment, blood samples were collected from the jugular vein and immediately delivered to the lab to determinebiochemical (serum protein: albumin and globulin), and hematological parameters. Exposing goats to temperature variation affected the physiological, hematological as well as biochemical parameters in all subjects. The female with a black body coat color was mostly affected. The heat stress induced an increase of RT and PR, an increase in waterconsumption while depression in food intake was observed. Blood platelets, hematocrits, red cell distribution, white blood cell and albumin were damaged in goats with black coat color compared to goats with white coat color. These variations in physiological, hematological and biochemical parameters in female black goat could affect its productive and reproductive performances in high-temperature environments.(AU)