THE INFLUENCES OF AGE OF FEMALE TETRANYCHUS KANZAWAI ON SEX RATIO AND LIFE CYCLE OF ITS PROGENY

Author(s):  
Chaining Thomas Shih
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.


2021 ◽  
Vol 13 (10) ◽  
pp. 96
Author(s):  
Eduardo Carvalho Faca ◽  
Fabrício Fagundes Pereira ◽  
Winnie Cezario Fernandes ◽  
Ivana Fernandes da Silva ◽  
Valmir Antônio Costa ◽  
...  

The study of the interaction between parasitoid and host, especially the age of these organisms, is an important step towards the implementation of biological control programs. Therefore, we investigated the performance of Ooencyrtus submetallicus (Hymenoptera: Encyrtidae) and Trissolcus sp. aff. urichi (Hymenoptera: Scelionidae) parasitizing eggs of Nezara viridula (Hemiptera: Pentatomidae), considering different ages of the parasitoids and the host. We performed four laboratory bioassays: two using females of O. submetallicus and Trissolcus sp. aff. urichi at 24, 48, 72, 96, 120, or 144 hours of age exposed to parasitism in N. viridula eggs (24 h) and two trials with N. viridula eggs at 24, 48, 72, 96, 120, or 144 hours exposed to the parasitism of O. submetallicus and Trissolcus sp. aff. urichi (24 h). We evaluated the percentage of parasitism and emergence, life cycle length, progeny, sex ratio, and the longevity of the parasitoids. The parasitism of O. submetallicus in N. viridula eggs was influenced by the age of the parasitoid, 120 hours being the minimum to obtain better parasitism. From this age on, there is interference in the longevity of the progeny. Trisolcus sp. aff. urichi, at all ages, parasitized N. viridula eggs relatively well, but with almost no emergence of the parasitized eggs. Females of O. submetallicus parasitized and developed in eggs of N. viridula of all ages. Females of Trissolcus sp. aff. urichi parasitized their host, but there was barely any emergence. These pieces of information regarding the breeding methodology contribute to the implementation of new protocols for the multiplication of these parasitoids in the laboratory, and later, their release in the field.


2019 ◽  
Vol 10 (3) ◽  
pp. 346-352
Author(s):  
Alexandre Martins Dos Santos ◽  
José Eudes De Morais Oliveira ◽  
Andréa Nunes Moreira de Carvalho ◽  
Martin Duarte De Oliveira ◽  
Carla Patrícia Oliveira de Assis ◽  
...  

Diadiplosis multifila was recently discovered feeding on Planococcus citri eggs in vineyards in the semi-arid northeast region of Brazil. The objective of the present paper was to study the biology of D. multifila in P. citri under constant temperatures of 22, 25, 28, and 31 °C. We evaluated its embryonic stage, egg viability, development period, survival of larva and pupa, longevity, average number of eggs, and sex ratio. D. multifila completed its life cycle in all temperatures except for 31 °C. The length of the embryonic period ranged from 4 to 7 days. The larval stage was longer at a temperature of 22 °C (8.6 days) and shorter at 28 °C (6.4). The pupal stage exhibited durations of 12.9, 10.4, and 8.2 days for temperatures of 22, 25, and 28 °C, respectively. The average viability in the larval stage was 97% and 83% in the pupal stage. The total life cycle took 16.7 (28 °C), 20 (25 °C), and 27 (22 °C) days to complete. The adults lived for approximately 2 days and the females produced on average 34, 25, and 19 eggs at temperatures of 22, 25, and 28 °C, respectively. The sex ratio varied from 0.46 to 0.54.


2020 ◽  
Vol 17 (2) ◽  
pp. 104
Author(s):  
Dosma Ulina Simbolon ◽  
Maryani Cyccu Tobing ◽  
Darma Bakti

<p><em>Stenocranus pacificus </em>Kirkaldy (Hemiptera: Delphacidae) is destructive pest on corn plants in South Lampung and it has been reported to cause corn damages in North Sumatra. The  objective of this research was to study some aspects biology of <em>S. pacificus</em> on corn plants in screenhouse. The research was conducted by observing the biology of <em>S. pacificus</em> that was reared on corn plants in screenhouse.<em> </em>The results showed that life cycle of <em>S. pacificus </em>was 38–47 (41,60 ± 3,19) days: egg was 9–11 (10,20 ± 0,79) days, the first instar nymph was 3–4 (3,70 ± 0,48) days, the second instar nymph was 3–4 (3,90 ± 0,32) days, the third instar nymph was 3–4 (3,70 ± 0,48) days, the fourth instar nymph was 3–4 (3,80 ± 0,42) days, and the fifth instar nymph was 3–4 (3,60 ± 0,52) days. Age of female was 13–17 (15,30 ± 1,34) days. It was longer than age of male which was 8–12 (10,10 ± 1,20) days. Female could produce 181–214 (197,60 ± 11,64) eggs during its life. The sex ratio was 1:1,98.</p>


2003 ◽  
Vol 37 (6) ◽  
pp. 722-728 ◽  
Author(s):  
Valeria Alejandra Labud ◽  
Liliana Graciela Semenas ◽  
Francisca Laos

OBJECTIVE: Odorous compounds produced at the biosolids composting plant in Bariloche (NW Patagonia) attract a variety of insects, mainly belonging to the order Diptera. In order to characterize these flies, collected specimens were taxonomically identified, their community characteristics were described and their sanitary and synanthropic importance and autochthonous or introduced character were determined. METHODS: Sampling was performed from October 1999 until March 2000. Adults were collected using an entomological net, and larvae and puparia were obtained from the composting material and incubated to obtain adults. Richness, abundance and sex ratio were calculated. RESULTS: A total of 9 taxa of Diptera were identified: Sarconesia chlorogaster, Phaenicia sericata, Calliphora vicina, Cochliomya macellaria, Ophyra sp, Muscina stabulans, Musca domestica, Sarcophaga sp and Fannia sp. Specimens of Anthomyiidae, Acaliptratae and one larva of Eristalis tenax were also found. Ophyra sp. was the most abundant taxa. All the captured Diptera belonged to introduced taxa. Most of them are considered to be eusynanthropic and/or hemisynanthropic and have sanitary importance as they may cause myiasis and pseudomyiasis. The high number of females registered and the finding of immature stages indicated that flies can develop their complete life cycle on biosolid composting windrows. CONCLUSIONS: The characterization of flies obtained in this study may be useful for defining locations of urban or semi-urban composting facilities. It also highlights the importance of sanitary precautions at such plants.


2004 ◽  
Vol 94 (6) ◽  
pp. 569-575 ◽  
Author(s):  
M.A.H. Smith ◽  
I.L. Wise ◽  
R.J. Lamb

AbstractSex ratios of populations of the wheat midge Sitodiplosis mosellana Géhin, developing on wheat Triticum aestivum L., were determined at reproduction, adult emergence, and dispersal. The patterns of sex ratio through the life cycle of S. mosellana result from: (i) a genetic mechanism that causes all or nearly all of the progeny of individual females to be a single sex, with an overall sex ratio that is slightly biased at 54–57% females; (ii) a differential mortality during diapause that increases the sex ratio to 60–65% females; (iii) mating which occurs near the emergence site followed by female dispersal which causes the post-dispersal sex ratio to rise to nearly 100% females; and (iv) oviposition which spreads eggs among different plants and assures that the next generation has a local sex ratio close to the population average. These changes in sex ratio through the life cycle have implications for using crop resistance or pheromones to manage S. mosellana, because mating takes place quickly near emergence sites, and because mated females but not males disperse from emergence sites to oviposition sites. Crop refuges used to protect resistance genes against the evolution of virulence by S. mosellana must be interspersed to prevent assortative mating that would occur in separate blocks of resistant and susceptible plants. Monitoring or mating disruption using a pheromone would be ineffective when wheat is grown in rotation with a non-host crop.


1978 ◽  
Vol 26 (4) ◽  
pp. 653 ◽  
Author(s):  
HG Cogger

A field study of the reproductive and fat cycles of the small agamid lizard Amphibolurus fordi was undertaken in two areas of mallee in central western New South Wales. The development of the gonads, including the histology of the testicular cycle, is described, together with correlated changes in the size of the inguinal fat bodies. The males emerge from winter torpor some 4-5 weeks before the females. The sex ratio approximates unity throughout the life cycle. Mating occurs from October to December; up to three clutches each of two or three eggs are laid in a season. The eggs hatch in 7-9 weeks after laying. The construction of the nesting chamber by the female is described. Apart from behaviour specifically geared to thermoregulation, two other behavioural types have been identified: male-female interactions involving only sexually mature individuals during the reproductive period, and non-sex-specific patterns which occur in both immature and mature individuals of either sex. Males are not territorial.


Sign in / Sign up

Export Citation Format

Share Document