General entomology

STREBLOTE PANDA HUBNER [1820] (LEPIDOPTERA, LASIOCAMPIDAE) IMPACT ON ORNAMENTALS

Author: CALVO HERNÁNDEZ DAVID.
Year: 2003.
University: SEVILLA [www.us.es].
Place of defense: FACULTAD DE BIOLOGÍA.
Place of preparation: FACULTAD DE BIOLOGÍA.

Summary: It monitors in the field on different host plants for caterpillars. Temporarily, the tracks were found along the entire year. Their presence central decreased during the summer. It has been found that the species spends the winter, at least in some of its host plants as active larva, feeding during sunny days. We discuss and analyze some of the major factors that can change and influence on the growth and development of the stadiums preimaginales of the species, such as regime average temperatures, caterpillars age, sex, uncle and nutritional composition of the food supplied. To that end, it evaluates the influence of different nutritional plants under controlled conditions using laboratory tests with and without food selection. Among the most significant results produced are the lack of food preferences indicted, and differences in mortality rates, speed of development, and the parameters of use of this feed calculated. The development of the species seems conditioned by the need to maintain a size pupal more or less constant, which ensures an adult reproductively competent and, well, there have been few differences in the size pupal. In response to variations pilot employed different responses were observed offset the adaptive nature. The most frequent have been the changes in the length of the stadium, the number of larval age and adjustment of the rates of consumption. The average temperature regime development significantly affect the duration of aloe preimaginales stadiums, but the number of dummy was virtually unchanged. The total development shorter occurred in 28Â ° C. The pupae and adults from reaching weights somewhat larger with increasing temperature. It develops and presents a model of development based on the accumulation of degree days and an estimate of the cardinal minimum temperatures for each stage of development preimaginal, and the full development. According to these estimates, the development of the egg would be prevented or slowed by temperatures below 8Â ° C, and the caterpillar and pupa around the 12.5Â ° C. The isotherm of 10Â ° C could be taken as indicative limit latitudinal distribution of the species partially explaining their geographical distribution and local levels. As for the ceiling, temperatures above 31Â ° C led to a turnaround in development times, which were extended, so deduciremos that the maximum temperature should be forthcoming this cardinal average. Increasing 3Â ° C in average temperatures regime breeding reduced on average by 25% the length of 5Â fifth stage and increased by 19% weight gain of caterpillars, with the consequence of higher weights initial stage, and rates consumption also higher. The increase in length of the larval stage was, in most cases, a decrease in growth rates. It analyzes the relationship between certain components and characteristics of the plants used nutritional food and behavior of the insect through its effects and impact on various parameters of growth and digestive efficiencies calculated by following standard procedures gravimetric own studies nutritional ecology. The mean values obtained ranged widely between different plants used as food for caterpillars. The growth of gross efficiency (ECI) is between 3.9 and 10.6%: 7.3 and 26.4 for the net efficiency of growth (ECD), and 33.1 and 62.2% for the efficiency of digestion (AD). The relative growth rate (RGR) was between 0.05 and 0.11 mg ps / mg.ps day -1, and the consumption rate (RCR) between 0.85 and 1.98 mg.ps / mg ps día-1. Compared with the bibliographic records found, rates and efficiencies of using food caterpillars are within the range varies 8-for 13d0 pio species of insects that feed on woody plants (trees and shrubs), in some cases with somewhat lower values, or close to the lower limit of the range of variation, which together are due to the long period of development of the caterpillars. Although the plants used as food for caterpillars varied in terms of proportion and quantity of characters and components analyzed, none of the plant parameters analyzed separately, with the exception of nitrogen, had ocntribución essential to the development of S.panda. The increase in the average content of leaf nitrogen decreased consumption rates daily and helped to reduce the length of the stadium. By contrast, the increase in hardness of the leaves promoted moves and the length of the stadium, diminishing the value of the digestive efficiencies. Both larval survival and speed of development varied in different plants tested, it was observed an overall increase in mortality associated with the age of caterpillars, and a long development, which reached up to 207 days, probably influenced by his conduct cryptic determined by a process of habituation to the food and related to adaptation to changes in quality. The increase in age of caterpillars led to a decline in the efficiency of digestion was associated with increased efficiency net growth. All of the food utilization rates tend to diminish in successive silent. Both males and females increased their efficiency net growth (ECD) is slightly higher in females with respect to male; along with a slight increase in the number of days that the females spent in each stadium and the presence of a usual move more, explain the final weight of the adult females, which doubles the male. We have studied the relationship between body size and fertility in female S.panda using paired and female virgins. All studied reproductive traits characteristic of the group are considered "capital breeders," dependent species for reproduction of resources accumulated during the larval stage. There was a strong relationship between the size adult indicators, such as the length of previous wing or body weight females with the pupal weight. Fertility is significantly affected by the pupal weight, as well as estimates of body size. The larger females proved more fruitful than small. The number of eggs found in virgin females and paired was similar, suggesting that females with the fuel load full of eggs: the average burden of eggs found in abdómenes of females was 278.4 + - 8.7 (SE), like the other. Lasiocampidae of similar size and weight. The females are aparearon and ovopositaron mostly the day after its revival, not observed any period prepuesta, and relationships with the female body size or age of the female. The size of the male did not affect either the size or the egg hatch rates. The results suggest that some of the determinants of larval development such as temperature and plant nutritional may influence fertility of the species, and therefore their population dynamics, through effects on weight pupal and adult body size, and especially causing asincronias in the life cycle. As input for the development of integrated management plans will provide some data on the complex parasite associated with S.panda, and a study of the biological effects of azadiractina on their tracks. To highlight the event, for the first time in the Iberian Peninsula, Drino maroccana Mesnil, 1951 (Diptera, Tachinidae); parasitoid species-specific. We checked the biological effect of a commercial formulation of azadiractina, a renowned actor biocide on the tracks S.panda through screening tests with and without food. The product tested, unlike recorded for other species of Lepidoptera, and groups of insects, and in line with the preference tests performed with different nutritional plants, showed no effect repellent or antialimentario clear, but there larval mortality dose . All treatments resulted in a significant reduction of growth, presumably through effects endocrine regulators. At higher doses used the product causes toxic effects, although few S.panda effects post-ingestión growth regulators appear to be the most important.

GENERAL ENTOMOLOGY