Lasioderma serricorne is known to be pest of tobacco, besides of attacking other products in storage. Anisopteromalus calandrae is an ectoparasitoid of coleopteran larvae also parasitizing the tobacco beetle. This stu...Lasioderma serricorne is known to be pest of tobacco, besides of attacking other products in storage. Anisopteromalus calandrae is an ectoparasitoid of coleopteran larvae also parasitizing the tobacco beetle. This study was aimed to evaluate the parasitism of A. calandrae on different densities of L. serricorne larvae grown in different diets and photoperiods, and to record the longevity and reproductive potential of A. calandrae. Individuals of L. serricorne were raised in three diets: wheat flour (F);wheat flour and brewer’s yeast (FY) and wheat flour and dried tobacco (FT). Different amounts of host larvae (10, 20, 50 and 100) for each diet were exposed to a couple of parasitoids. The same larval densities from diet F were exposed for 24 h to a couple of adult parasitoids maintained in three photoperiods (0:24, 12:12 and 24:0 - scotophase: photophase). The highest values of apparent parasitism were in the density of 50 larvae in the FY diet (96.34%) and 100 F (92.91%). There was no significant difference in the parameters in each photoperiod in all larval densities. However, the treatment in which hosts and parasitoids always remained in scotophase, was the one that had a significantly higher sex ratio. Females had longer longevity than males surviving for up to 25 days. On the fourth day of larvae exposure occurred, the maximum number of offspring generated. It is inferred that A. calandrae has potential to be used as a control agent for coleopterans that attack stored products.展开更多
Among the chrysomelids, some species are considered agricultural pests, such as some representatives of Epitrix spp. Popularly known as tobacco flea, these beetles cause damage to tobacco (Nicotiana tabacum L.) by fee...Among the chrysomelids, some species are considered agricultural pests, such as some representatives of Epitrix spp. Popularly known as tobacco flea, these beetles cause damage to tobacco (Nicotiana tabacum L.) by feeding on the leaf surface, causing injuries, reducing productivity and the final quality of the product to be marketed. However, studies of the biology and interactions of these individuals with the environment become essential in order to develop effective and sustainable control measures. The objective of this study was to analyze the distribution and population fluctuation of Epitrix spp., as well as to evaluate the possible influence of temperature, rainfall and adjacent vegetation on the population dynamics of this beetle in organic tobacco growing in the municipality of Santa Cruz of the South, RS. The collections were carried out weekly during the 2011/2012 harvest, using Malaise and Pit-fall traps, distributed in four points along three lines. A total of 1584 individuals belonging to the genus Epitrix were collected, and their greatest abundance was observed in late January and early February 2012 due to climatic factors, such as rainfall and temperature, favorable to the development of specimens and the tobacco leaf harvesting reduced the availability of food and conditioned a greater movement of these individuals in the crop. The results presented here are of great importance for deciding the best methodology for controlling the smoke flea, as well as knowing the influence of abiotic factors on the behavior of these organisms in the field.展开更多
基金the Conselho Nacional de Pesquisa—CNPq for financial support in DTI-C scholarships and masters scholarship
文摘Lasioderma serricorne is known to be pest of tobacco, besides of attacking other products in storage. Anisopteromalus calandrae is an ectoparasitoid of coleopteran larvae also parasitizing the tobacco beetle. This study was aimed to evaluate the parasitism of A. calandrae on different densities of L. serricorne larvae grown in different diets and photoperiods, and to record the longevity and reproductive potential of A. calandrae. Individuals of L. serricorne were raised in three diets: wheat flour (F);wheat flour and brewer’s yeast (FY) and wheat flour and dried tobacco (FT). Different amounts of host larvae (10, 20, 50 and 100) for each diet were exposed to a couple of parasitoids. The same larval densities from diet F were exposed for 24 h to a couple of adult parasitoids maintained in three photoperiods (0:24, 12:12 and 24:0 - scotophase: photophase). The highest values of apparent parasitism were in the density of 50 larvae in the FY diet (96.34%) and 100 F (92.91%). There was no significant difference in the parameters in each photoperiod in all larval densities. However, the treatment in which hosts and parasitoids always remained in scotophase, was the one that had a significantly higher sex ratio. Females had longer longevity than males surviving for up to 25 days. On the fourth day of larvae exposure occurred, the maximum number of offspring generated. It is inferred that A. calandrae has potential to be used as a control agent for coleopterans that attack stored products.
文摘Among the chrysomelids, some species are considered agricultural pests, such as some representatives of Epitrix spp. Popularly known as tobacco flea, these beetles cause damage to tobacco (Nicotiana tabacum L.) by feeding on the leaf surface, causing injuries, reducing productivity and the final quality of the product to be marketed. However, studies of the biology and interactions of these individuals with the environment become essential in order to develop effective and sustainable control measures. The objective of this study was to analyze the distribution and population fluctuation of Epitrix spp., as well as to evaluate the possible influence of temperature, rainfall and adjacent vegetation on the population dynamics of this beetle in organic tobacco growing in the municipality of Santa Cruz of the South, RS. The collections were carried out weekly during the 2011/2012 harvest, using Malaise and Pit-fall traps, distributed in four points along three lines. A total of 1584 individuals belonging to the genus Epitrix were collected, and their greatest abundance was observed in late January and early February 2012 due to climatic factors, such as rainfall and temperature, favorable to the development of specimens and the tobacco leaf harvesting reduced the availability of food and conditioned a greater movement of these individuals in the crop. The results presented here are of great importance for deciding the best methodology for controlling the smoke flea, as well as knowing the influence of abiotic factors on the behavior of these organisms in the field.
