Densidade de fêmeas de Palmistichus elaeisis Delvare & LaSalle, 1993 (Hymenoptera: Eulophidae) para sua reprodução em pupas de Anticarsia gemmatalis Hübner, 1818 (Lepidoptera: Noctuidae)

Abstract

A densidade de parasitoides por hospedeiro influencia nas suas principais características biológicas. Assim, o objetivo desse trabalho foi avaliar o desenvolvimento do parasitoide Palmistichus elaeisis Delvare & LaSalle, 1993 (Hymenoptera: Eulophidae) em pupas de Anticarsia gemmatalis Hübner, 1818 (Lepidoptera: Noctuidae) expostas nas densidades de 1:1, 2:1, 4:1, 6:1, 8:1, 10:1 ou 12:1 parasitoides/hospedeiro, respectivamente. Os parasitoides permaneceram em contato com as pupas por 24 horas em tubos de vidro (14,0 x 2,2 cm), acondicionadas em câmara climatizada a 25 ± 1º C, 70 ± 10% de UR e fotofase de 14 horas. Observou-se 54,54 e 90,90% de pupas parasitadas nas densidades de 1:1 e 2:1, respectivamente, e 100,00% nas demais densidades com melhor índice de emergência (72,72%) na densidade 6:1. A duração do ciclo de vida (ovo-adulto) decresceu com o aumento da densidade de fêmeas e variou de 20 a 22 dias. A progênie variou de 16 a 225 descendentes por pupa, com melhor resultado na densidade 8:1. A razão sexual do parasitoide variou de 0,95 ± 0,00 a 0,97 ± 0,01, sem diferença significativa e o comprimento do corpo de fêmeas e de machos variou de 1,95 ± 0,02 a 2,22 ± 0,03 mm e de 1,49 ± 0,02 a 1,87 ± 0,01 mm, respectivamente. Seis a oito fêmeas de P. elaeisis por pupa de A. gemmatalis proporcionam maior emergência e progênie do parasitoide, viabilizando sua criação massal.

Do parasitoid density and host age affect the parasitism of Palmistichus elaeisis (Hymenoptera: Eulophidae)?

“…The development duration of P. elaeisis with different parasitoid densities and host age of S. frugiperda from 21.63 ± 1.07 to 24.75 ± 0.02 days was similar to that observed in A. gemmatalis pupae exposed to different densities of parasitoids, with 20 to 22 days (PASTORI et al, 2012).…”

“…The similarity in tibia length at different densities of parasitoids and host ages is probably due to the similar competition of the larvae by nutrients and absence of superparasitism in this host. In the reared of natural enemies, it is expected to obtain individuals with greater body size, because they have positive correlation with quality indicators such as longevity, copula preference, fecundity, reproductive longevity, progeny emergence and sex ratio, which may indicate parasitoid efficiency (PASTORI et al, 2012).…”

Reproduction of Trichospilus diatraeae (Hymenoptera: Eulophidae) with Different Densities and Parasitism Periods in Anticarsia gemmatalis (Lepidoptera: Noctuidae) Pupae

“…Increasing the density of Melittobia digitata Dahms, 1984 (Hymenoptera: Eulophidae) by pupa of Neobellieria bullata (Parker, 1916) (Diptera: Sarcophagidae) reduced parasitoid development time (SILVA-TORRES & MATTHEWS 2003). The duration of the life-cycle of Palmistichus elaeisis Delvare & LaSalle, 1993 (Hymenoptera: Eulophidae) decreased with increasing density of females by pupae of A. gemmatalis (PASTORI et al 2012b). In Tetrastichus howardi (Olliff, 1893) (Hymenoptera: Eulophidae), variation of the density of females per pupae of D. saccharalis did not influence the duration of the cycle (days) of the parasitoid (COSTA et al 2014b).…”

Side-effects of pesticides on the generalist endoparasitoid Palmistichus elaeisis (Hymenoptera: Eulophidae)

“…Caterpillars of the pest were obtained from the Laboratory of Biological Control of Insects (LCBI-BIOAGRO) at the Universidade Federal de Viçosa (UFV), where this insect is reared on an artificial diet 48 , with 125 g bean, 62.4 g beer yeast, 100 g wheat germ, 100 g soy protein, 50 g casein, 35 g agar, 5 g nipagin, 6 g ascorbic acid, 3 g sorbic acid, 6 mL formol at 40% in water, and 10 mL vitaminic solution. Second instar caterpillars were reared in 500 mL plastic containers, receiving soybean leaves ad libitum (3–5 times) or an artificial diet according to the treatments until pupae stage.…”

“…The tubes were closed with a cotton plug. Anticarsia gemmatalis pupae with 48–72 h-old were exposed to P. elaeisis females for 24 h at a density of 6:1 females:pupae 48 , in the same rearing conditions as for A. gemmatalis . These new offspring were used in the experiments.…”