Ecología de la polilla del repollo, Plutella xylostella (L.) (Lepidoptera: Plutellidae). II. Ciclo de Vida.
Abstract
El ciclo de vida de la polilla del repollo, Plutella
xylostella (L.) (Lepidoptera: Plutellidae), se estudió
bajo temperatura constante (20 +- 1º C) y con 16 ho-
ras de luz (08.00 a 2400) por día proveniente de seis
tubos fluorescentes de 125 vatios, de 2.40 m de longi-
tud. La humedad relativa no fue controlada, pero
permaneció entre 44 y 55% durante el día y hasta
14% más alto durante la nocha. A manera de compa-
ración se hizo observaciones en el laboratorio bajo
t5emperatura variable de la calefacción central domés-
tica (18 a 22º C, promedio 20ºC) y luz natural varia-
ble a través de ventanas de vidrio. Para reducir el efec-
to de luz lateral, las jaulas fueron rotadas 90º cada
día y la posición con respecto a la ventana se cambió.
No se controlo la humedad relativa. Se usó jaulas
plásticas circulares transparentes (aproximadamente
10 cm de diámetro y 4.5 cm de alto); las jaulas tenían
dentro una capa de cinco milímetros de arena hume-
decida. Se sacó discos de 2.5 cm de diámetro de hojas
tiernas de plantas jóvenes de repollo. Se permitió a
adultos de pLutella que ovipusieran por períodos de
.seis horas y los huevos recién puestos fueron coloca-
dos en los discos de hojas.
Información Adicional
| Correo Electrónico | psalinas@ula.ve |
| Descripción | Turrialba: Vol.36, Nº 1, Trimestre Enero-Marzo 1986 |
| Resumen en otro Idioma | The life history of the diamondback moth, plutella xylostella (L.) (Lepidóptera:plutellidae), was studied under constant temperature (20+- 1º C) and with 16 hours light (08.00 to 2400) per day from six 125-watts fluorescent tubes 2.40 m long. Relative humidity was not controlled but remained between 44-52% during the day and up to 14% higher at night. As a means of comparison, observations were made in the laboratory under variable temperature from domestic-type central heating (average 20º C) and variable daylight coming through a glass window; to reduce the side- light effect, the cages were rotated 90º everyday, and posi- tion with respect to the window was changed. Relative humidity was not controlled. Circular transparent plastic cages (aprox. 10cm diamater, and 4.5 cm height) were used; inside the cages was a five mm layer of moistured sand. One inch diameter leaf discs were taken from tender leaves of young cabbage plants. The discs were placed in the same position as they were in the leaf. Adult Plutella were allowed to oviposit for short periods of about six hours. Recently laid eggs were placed in the leaf disch. Observations were made regularly. more than once in a day. At 20º C constant temperature the total life duration was 41.3 days. First to fourth instar: 12.7 days. pre-pupa: 1.3 days. Pupa: 712 days. Mean development times were longer at constant temperature except in fourth instar and pupa. |
| Colación | 130-134 |
| País | Venezuela |