Biological aspects and life table of Uroleucon ambrosiae (Thomas, 1878) as a function of temperature

Abstract

The aphid Uroleucon ambrosiae (Thomas) is considered a pest of hidroponically-grown lettuce, but basic and applied information on its control are scarce in Brazil. The aim of this study was to determine the effect of different temperatures on biological aspects and life history of U. ambrosiae (Thomas) developing on hydroponic lettuce (Lactuca sativa L.) crop. Newly emerged nymphs were placed on 4-cm discs of hydroponic lettuce, var. Verônica, which were maintained on 5-cm Petri dishes, at temperatures of 15, 20 and 25ºC and 14 h photophase, and inside a greenhouse, within micro-cages at room temperature. The duration of development in all nymphal stages varied inversely to temperature. Nymphs maintained at 20ºC and 25ºC, had similar development period. However, at fluctuating greenhouse temperatures (daily mean = 21ºC), different results were obtained, which was also true for the pre-reproductive, reproductive and post-reproductive periods. Daily and total fertilities at 20ºC were better in comparison to the other treatments. The highest mortality rate of aphids occurred under greenhouse conditions. The production of 1.28 nymphs per female per day, the time needed for the population to double in size (TD=2.77days), and the intrinsic rate of population increase (r m=0.25), were similar for in insects maintained at 20 and 25ºC. On the other hand, time interval between generations (T) and the net reproductive rate (Ro) were higher at 20ºC. In the greenhouse, even though T was similar to laboratory conditions at 20 and 25ºC, the R0, r m and l parameters were lower and TD was higher. Based on biological aspects, fertility and life expectancy tables, constant temperature of 20ºC is the most suitable for U. ambrosiae.

Functional response of Chrysoperla nipponensis and C. carnea (Neuroptera: Chrysopidae) to the cotton aphid Aphis gossypii Glover (Homoptera: Aphididae) under laboratory conditions

“…In this study, C. nipponensis and C. carnea presented a Type II functional response (Holling, 1959), similar to several reports on the functional response in C. carnea, C. rufilabris, C. externa, and C. congrua (Stark and Whitford, 1987;Nordlund and Morrison, 1990;Kabissa et al, 1996;Fonseca et al, 2000;Stewart et al, 2002;Auad and Moraes, 2003). Although the functional response-204…”

Doğa koşullarında Solanum nigrum üzerinde üretilen Bemisia tabaci’nin gelişmesi ve canlılık oranı

“…The developmental time of total preadult of the whitefly declines with increasing temperature. This inverse relationship between development time and temperature has been also observed in other insect species (Uygun & Atlihan, 2000;Auad & Moraes, 2003;Emana, 2007;Atlihan & Chi, 2008;Musana et al, 2013). On the other hand, this study was carried out in two different seasons, and seasonal changes may affect the nutritive composition of plants, including secondary plant metabolites which might affect developmental times and mortality rate.…”

“…Temperature is an important factor for development and population growth of all insects (Bale et al, 2002;Auad & Moraes, 2003;Musana et al, 2013). Knowledge of how temperature influences the development and mortality of an insect species is important for understanding its potential population growth and geographical distribution.…”

Reproduction and fertility life table of three aphid species (Macrosiphini) at different temperatures

“…At temperatures between 16 and 19ºC, the estimated duration of the period decreased from 19.9 to 11.2 days, respectively, but then remained relatively stable until 25ºC (estimated length 8.7 days), and finally decreased to 3.0 days at 28ºC. Auad & Moraes (2003) reported that the reproductive period of U. ambrosiae lasted 15.57 days at 15ºC, 12.23 days at 20ºC and 8.47 days at 25ºC, values that were similar to those reported here.…”