scholarly journals Densidade de fêmeas de Trichospilus diatraeae (Hymenoptera: Eulophidae) por pupa de Diatraea saccharalis (Lepidoptera: Crambidae)

2013 ◽  
Vol 13 ◽  
Author(s):  
Elizangela Leite Vargas ◽  
Fabricio Fagundes Pereira ◽  
Vanessa Rodrigues Ferreira Calado ◽  
Daniele Fabiana Glaeser ◽  
Bruna Aparecida Cáceres Rodrigues ◽  
...  

Density of parasitoid females affects their capacity to develop within the host. The number of Trichospilus diatraeae (Hymenoptera: Eulophidae) females per pupa of Diatraea saccharalis (Lepidoptera: Crambidae) was adjusted to study the effect of parasitoid production in the laboratory. Host pupae were parasitised by females of T. diatraeae at densities of 1:1, 7:1, 14:1, 21:1, 28:1 and 35:1 (parasitoid:host). The females of the parasitoid remained in contact with pupae for 24 h in glass tubes (8.5 × 2.5 cm), packed in a climatic chamber regulated at 25 ± 2ºC, 70 ± 10% relative humidity and light regime of 14 h. The percentage of parasitism and emergence of T. diatraeae on pupae of D. saccharalis was 100% in all parasitoid densities. The length of thr cycle (egg-adult) of Trichospilus diatraeae was 19.25 ± 0.22 days at a density of 1:1 and 17.00 ± 0.00 days at 35:1. The offspring number of T. diatraeae was 106.00 ± 12.38 and 514.67 ± 54.55 individuals per pupa at densities of 1:1 and 35:1, respectively. The sex ratio decreased with increasing density, ranging between 0.97 ± 0.01 and 0.89 ± 0.01 at densities of 1:1 and 35:1, respectively. The percentages of parasitism and emergence of T. diatraeae on pupae of D. saccharalis were not affected by the densities of female parasitoids. The densities of 14 to 21 females of T. diatraeae per pupa of D. saccharalis are suitable for rearing this parasitoid under laboratory conditions.

2010 ◽  
Vol 82 (2) ◽  
pp. 323-331 ◽  
Author(s):  
Fabricio F. Pereira ◽  
José C. Zanuncio ◽  
José E. Serrão ◽  
Teresinha V. Zanuncio ◽  
Dirceu Pratissoli ◽  
...  

Palmistichus elaeisis Delvare and LaSalle (Hymenoptera: Eulophidae) is a gregarious and polyphagous parasitoid mainly of Lepidoptera pupae. The objective of this paper as to study the developent of parasitoid on Bombyx mori L. (Lepidoptera: Bombycidae) pupae exposed to one, nine, 18, 27, 36, 45 or 54 female P. elaeisis, respectively. The females of the parasitoid remained in contact with pupae for 24 hours in glass tubes (14.0 x 2.2 cm), packed in a climatic chamber regulated at 25 ± 2°C, 70 ± 10% relative humidity and photo phase of 12 hours. With the exception of density 1:1 (72.72%), in other densities parasitism was 100%. Adults of P. elaeisis did not emerge from pupae at densities of 1:1 and 9:1, but 100.0% of parasitoid emergence was observed at the density of 45:1 and 54.54% at 54:1. The duration of the life cycle of this parasitoid ranged from 20 to 28 days. P. elaeisis produced 49 to 589 descendants per pupa of B. mori. The sex ratio of P. elaeisis ranged from 0.93 ± 0.01 to 0.97 ± 0.01 without differences with 18, 27, 36, 45 and 54 females/host. This parasitoid should be reared with the density of 45 females per pupa of B. mori.


1954 ◽  
Vol 45 (4) ◽  
pp. 647-659 ◽  
Author(s):  
E. S. Narayanan ◽  
R. P. Chaudhuri

Experiments were conducted to investigate oviposition and host selection by Stenobracon deesae (Cam.), a Braconid parasite of certain Lepidoperous borers of sugar-cane, maize and sorghum in India. The fecundity and sex-ratio of this parasite and the duration of its life-cycle were also studied.Chilo zonellus (Swinh.) and Corcyra cephalonica (Staint.) were used as hosts. The former is one of the principal hosts in the field, but the latter is not normally a host of this parasite.The femal Stenobracon normally avoids laying eggs on hosts that are already parasitised by its own kind when unparasitised hosts are available; but in the absence of healthy hosts or when these are too crowded, parasitised hosts are attacked by it.At a temperature of 26°C. and relative humidity of 75 per cent., the life-cycle of the parasite was completed, on an average, in 23·3 days, but under laboratory conditions at Delhi it took 14·1 days in June-July and 43·7 days in November-December. The average duration of adult life of females in June-February, mainly in ordinary laboratory conditions, was 35·7 days, and single females lived as long as 122 and 128 days. The adult male lived for 42·7 days on the average.In the laboratory, the female lays about 24 eggs on an average, but only about one-third of them yield adults.Males predominate. The sex-ratio appears to vary according to the host; among adults reared on Chilo larvae, 28·8 per cent. were females, but among others reared on Corcyra larvae, only 6·2 per cent. were females.The phenomena of discrimination between parasitised and unparasitised hosts and of the change of sex-ratio with change of host are discussed. It is suggested that the ovipositor enables the parasite to recognise the host and that the stimuli received by the ovipositor from the host influence the functioning of the spermatheca which in turn controls fertilisation and finally the sex of the progeny.


1997 ◽  
Vol 26 (1) ◽  
pp. 87-91 ◽  
Author(s):  
Meire N. Yamauchi ◽  
Nivar Gobbi ◽  
José Chaud-Netto ◽  
Ana E. Campos-Farinha

Females of Cotesia flavipes (Cam.) were individually introduced into Petri dishes containing one larva of its host Diatraea saccharalis (Fabr.). Each C. flavipes female was allowed to oviposit once or twice in the same larva. Time of emergence of larvae and adults, sex-ratio, number of non-viable larvae and pupae, and longevity of adults of C. flavipes were recorded. Data revealed that two successive ovipositions in the host did not affect sex-ratio, but increased number of parasitoids and number of non-viable larvae and pupae.


2001 ◽  
Vol 61 (4) ◽  
pp. 661-666 ◽  
Author(s):  
J. A. TESTON ◽  
A. SPECHT ◽  
E. CORSEUIL

Larvae of Anicla infecta (Ochsenheimer, 1816) (Noctuidae) feed upon many grasses and may be harmful to cereals and fodder of economic importance. This study was developed aiming to contribute to knowledge of the biology of this species. The rearing was done in an environmental chamber with the following settings: temperature of 25 ± 1ºC; relative humidity of 70% <FONT FACE=Symbol>±</FONT> 10%, and photoperiod of L14: D10. The larvae fed on ryegrass, Lolium multiflorum Lam. The results express the mean and standard error for the length of every stage in days. For each stage we observed the following time of development: egg 3.2 <FONT FACE=Symbol>±</FONT> 0.09; larvae 18.7 <FONT FACE=Symbol>±</FONT> 0.07; pre-pupae 3.3 <FONT FACE=Symbol>±</FONT> 0.04; pupae 12.6 <FONT FACE=Symbol>±</FONT> 0.14; and adult longevity was 12.1 <FONT FACE=Symbol>±</FONT> 1.03. Also the pre-egg-laying period was 4.4 <FONT FACE=Symbol>±</FONT> 0.59; the egg-laying period was 8.1 <FONT FACE=Symbol>±</FONT> 0.84; and the post-egg-laying period was 0.3 <FONT FACE=Symbol>±</FONT> 0.14. The mean number of egg-laying cycles per female was 6.7 <FONT FACE=Symbol>±</FONT> 0.73; that of eggs per cycle was 77.5 <FONT FACE=Symbol>±</FONT> 4.37; and total eggs per female was 521.4 <FONT FACE=Symbol>±</FONT> 47.36.


2009 ◽  
Vol 78 (5) ◽  
pp. 1007-1014 ◽  
Author(s):  
Esa Koskela ◽  
Tapio Mappes ◽  
Tuuli Niskanen ◽  
Joanna Rutkowska

1960 ◽  
Vol 11 (4) ◽  
pp. 664 ◽  
Author(s):  
MW McDonald

Fertile White Leghorn eggs were stored for periods ranging from 24 hr to 7 days in environments controlled at 40, 60, or 80°F and 70 per cent. relative humidity. The eggs were then incubated, and observations on numbers of incubator clears and dead embryos at 10 days and again at 17 days, numbers of chickens hatched, weight at hatching, sex ratio, weight of pullets at 14 days of age, and mortalities were recorded. Eggs stored at 40 and 60°F showed no effect of age of egg on number of clears, dead embryos, or number of chickens hatched. Eggs stored at 80°F showed a rapid fall in number of chickens hatched with age of egg before incubation, this effect being produced by increases in number of clears and dead embryos. Storage at 40°F produced a lower number of chickens hatched than at 60°F, owing to a higher number of incubator clears. There was no difference in sex ratio between chickens hatched from eggs stored at 60 and 80°F, neither departing significantly from 50 per cent. pullets. However, storage at 40°F produced significantly more pullets than cockerels, 54.6 per cent. of the chickens being pullets. Storage temperature and age of egg did not affect the hatching weight of the chickens, but when 14 days old, pullets from the eggs stored at 80°F were significantly heavier than pullets from the other groups.


2015 ◽  
Vol 24 (3) ◽  
pp. 357-360 ◽  
Author(s):  
Michele da Costa Pinheiro ◽  
Elizabete Captivo Lourenço ◽  
Iwine Joyce Barbosa de Sá-Hungaro ◽  
Kátia Maria Famadas

The natural hosts of Amblyomma nodosum in the immature stages are a variety of birds and the anteater in the adult stage. However, so far no data have been published about this tick’s life cycle. To fill this gap, a record was made of its development under laboratory conditions. All the procedures were controlled in a BOD chamber set at 27±1 °C and 80±10% relative humidity and scotophase. The parasitic stages were raised on rabbits (Oryctolagus cuniculus Linnaeus, 1758), from which more than 50% of larvae and nymphs were recovered, although only a small portion performed ecdysis. The adults did not fixed on the rabbits, which suggests that the experimental conditions were unsuitable for the requirements of this species. The data obtained here indicate that A. nodosum is highly dependent on its host and environment whereas under laboratory conditions and host chosen for the study was not obtained satisfactory results and new studies with different hosts and new environmental conditions should be elaborated.


2016 ◽  
Vol 50 (1-2) ◽  
pp. 13-23 ◽  
Author(s):  
Sylvia Bassey Umoetok Akpassam ◽  
Beatrice Ngozi Iloba ◽  
Idorenyin Asukwo Udo

1991 ◽  
Vol 123 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Martha J. Farkas ◽  
Gordon A. Surgeoner

AbstractIxodes cookei Packard required ca. 14 weeks to complete development under laboratory conditions, using groundhogs [Marmota monax (L.)] as the blood meal source and off-host conditions of 25–29°C and 93–100% relative humidity. All three post-embryonic instars engorged in ca. 6–8 days. Larvae and nymphs maintained at 25°C moulted to the next instar ca. 18–20 days after detachment. Moult occurred under conditions of either a 0L:24D or a 16L:8D photoperiod. Adult females increased in weight ca. 49-fold from the unfed to the engorged state, attaining a weight of 194.1 ± 15.0 (mean ± SE) mg and producing 1281.5 ± 139.1 (mean ± SE) eggs at 29°C. The pre-ovipositional and ovipositional periods were 4.7 ± 0.3 and 20.2 ± 1.7(mean ± SE) days, respectively, at 29°C. Fifty percent of eggs were deposited within the 1st week of the ovipositional period at 29°C. First egg hatch at 29°C occurred ca. 31 days after oviposition was started. Eggs maintained at 10°C did not hatch, and the thermal threshold for egg development was calculated to be 11.2°C.


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