scholarly journals The influence of the fasting period on the number of nymphal instars and on the sex ratio of Argas (Persicargas) miniatus (Acari: Argasidae)

2010 ◽  
Vol 19 (3) ◽  
pp. 164-168 ◽  
Author(s):  
Huarrisson Azevedo Santos ◽  
Isabele da Costa Angelo ◽  
Marcos Pinheiro Franque ◽  
Usha Vashist ◽  
Aline Falqueto Duarte ◽  
...  
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Sex Ratio ◽  
Gallus Gallus ◽  
Fourth Instar ◽  
Starvation Period ◽  
Experimental Conditions ◽  
Fasting Period ◽  
The Third ◽  
First Instar

The current study investigated the biology of nymphs of the first and second instars of Argas (Persicargas) miniatus. Nymphs were deprived of food for 15, 30 or 60 days and held at 27 ± 1 ºC and 80 ± 10% relative humidity (controlled conditions) or at room conditions of temperature and relative humidity. Nymphs of first instar deprived of food for 15 or 30 days molted to second and third instars in both controlled and room conditions. Nymphs of the first instar deprived of food for 60 days had 28 and 37% mortality in controlled and room conditions, respectively; and survivors did not attach to the host. Nymphs of the second instar, deprived of food for 60 days, molted either to the third instar or to males after feeding on Gallus gallus, and the nymphs of the third instar developed to adults (42.42% males and 36.36% females when nymphs were held in controlled temperature and humidity conditions, and 40.54% males and 48.65% females when nymphs were held in room conditions). The remainder of the nymphs molted to the fourth instar and then molted to females. In conclusion, the nymphal starvation period of 60 days determined the number of nymph instars in the life cycle of A. miniatus under the experimental conditions studied.

scholarly journals Biologi Stenocranus pacificus Kirkaldy (Hemiptera: Delphacidae) pada tanaman jagung (Zea mays L.) di rumah kasa

2020 ◽  
Vol 17 (2) ◽  
pp. 104
Author(s):  
Dosma Ulina Simbolon ◽  
Maryani Cyccu Tobing ◽  
Darma Bakti
Keyword(s):  
Zea Mays ◽  
Life Cycle ◽  
Sex Ratio ◽  
Zea Mays L ◽  
Instar Nymph ◽  
Fourth Instar ◽  
The Third ◽  
First Instar ◽  
Corn Plants ◽  
North Sumatra

<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>

Observations on Rate of Growth, Coloration, and the abnormal Six-instar Life-cycle in Locusta migratoria migratorioides, R. &. F.

1936 ◽  
Vol 27 (1) ◽  
pp. 77-85 ◽  
Author(s):  
K. H. L. Key
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Light Intensity ◽  
Locusta Migratoria ◽  
Fourth Instar ◽  
The Other ◽  
Locusta Migratoria Migratorioides ◽  
The Third ◽  
Rate Of Growth ◽  
Progression Factor

1. All material was reared under constant conditions of temperature, light intensity and relative humidity. Two relative humidities were used—very wet and very dry. In some cases various coloured backgrounds were used. All material was solitaria, and was kept isolated.2. Average weights were calculated from weighings made at all periods within the stadia, and thus represent the weights at the mid-points of the stadia.3. The figures could not be fitted to the theory of a progression factor of 2.4. Females are on the average 50 per cent, heavier than males even in the third instar; the sexes can probably be distinguished in this way much earlier.5. The first three stadia are of about the same length; the fourth is longer, the fifth much longer.6. The percentage rate of growth between the mid-points of successive stadia is of the same order for all pairs, though somewhat lower for the first and last pairs.7. Hoppers kept in a very dry atmosphere are much lighter than those kept wet —proportionally more so in the later than in the earlier instars; on the other hand each stadium is lengthened—proportionally more so in the earlier than in the later stadia; the percentage rate of growth is just half that of hoppers kept wet.8. The findings of Faure in regard to the causes of differences in coloration were fully confirmed.9. The occurrence of a sixth instar in the females is due to an inherited factor.10. This “ extra ” instar may represent an extra morphological third instar or an extra morphological fourth instar.

scholarly journals Life cycle, morphometrics and damage assessment of the Khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae) on stored groundnut

2009 ◽  
Vol 54 (2) ◽  
pp. 135-142
Author(s):  
A.K. Musa ◽  
M.C. Dike
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Damage Assessment ◽  
Development Time ◽  
Fourth Instar ◽  
Adult Longevity ◽  
Trogoderma Granarium ◽  
First Instar ◽  
Khapra Beetle ◽  
Average Fecundity

The life cycle of the Khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae) on stored groundnut was studied under fluctuating laboratory conditions of 25?5?C and 70?5% relative humidity. There were five larval instars and the total development time from egg to adult ranged from 37 to 40 days with an average of 37.95 days. The duration of each developmental stage was egg: 6.05 days; first instar: 3.8 days; second instar: 4.7 days; third instar: 5.6 days; fourth instar: 6.2 days; fifth instar: 6.8 days and pupa: 4.8 days. Females had an average fecundity of 80.2 eggs. Mean adult longevity was 12.4 days. .

THE IMMATURE STAGES OF PTYCHOPTERA LENIS LENIS (DIPTERA: PTYCHOPTERIDAE) WITH NOTES ON THEIR BIOLOGY

1973 ◽  
Vol 105 (8) ◽  
pp. 1091-1099 ◽  
Author(s):  
I. D. Hodkinson
Keyword(s):  
Life Cycle ◽  
Water Depth ◽  
Adult Stage ◽  
Atmospheric Oxygen ◽  
Adult Emergence ◽  
Fourth Instar ◽  
Immature Stages ◽  
Experimental Conditions ◽  
Marginal Areas ◽  
Pharate Adult

AbstractThe four larval instars and the pupa of Ptychoptera lenis lenis Osten Sacken are described. Instars 2 to 4 are very similar morphologically but instar 1 is markedly different. Both a pharate pupal and a pharate adult stage were observed. Larvae are found in stagnant marginal areas of ponds where water depth does not exceed 4 cm and where benthic deposits of plant detritus exceed 8 cm. Fourth instar larvae, under experimental conditions, survived up to 45 days without contact with atmospheric oxygen but development was arrested. P. lenis has a 1 year life cycle with an extended adult emergence season from late May to the end of July.

scholarly journals The density of females of Palmistichus elaeisis Delvare and LaSalle (Hymenoptera: Eulophidae) affects their reproductive performance on pupae of Bombyx mori L. (Lepidoptera: Bombycidae)

2010 ◽  
Vol 82 (2) ◽  
pp. 323-331 ◽  
Author(s):  
Fabricio F. Pereira ◽  
José C. Zanuncio ◽  
José E. Serrão ◽  
Teresinha V. Zanuncio ◽  
Dirceu Pratissoli ◽  
...  
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Sex Ratio ◽  
Bombyx Mori ◽  
Reproductive Performance ◽  
Climatic Chamber ◽  
Glass Tubes ◽  
Bombyx Mori L

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.

The Bionomics of an African Megarhinus (Dipt., Culicidae) and its possible use in Biological Control

1951 ◽  
Vol 42 (2) ◽  
pp. 355-370 ◽  
Author(s):  
J. Muspratt
Keyword(s):  
Biological Control ◽  
Life Cycle ◽  
Aedes Aegypti ◽  
Pacific Islands ◽  
Natural Habitat ◽  
Fourth Instar ◽  
Medium Size ◽  
Sugar Solution ◽  
First Instar ◽  
Annual Range

Living specimens of Megarhinus brevipalpis were transported from southern Natal to Johannesburg to establish an insectary-bred colony. The natural habitat of these predatory mosquitos consisted of small isolated patches of sub-tropical forest, in which the rainfall is 40–50 ins. (102–127 cm.) with a mean winter temperature of 64°F. (17·7°C.) and an annual range of 27°–33°F. (15°–18°C). The breeding places were leaf axils of Strelitzia nicolai (a plant resembling a wild banana), small rot holes in trees and larger ones in Strelitzia stumps. The larvae were collected from leaf axils with an apparatus consisting of a rubber bulb to which were attached lengths of glass and rubber tubing.The insectary was a room 9 ft.×8 ft. 6 ins. and 9 ft. high which was kept at tropical heat and humidity. Mating of the adults was observed, copulation being effected while at rest or in flight. Oviposition was usually accomplished in flight but also while at rest on the surface of the water. In the summer time two females, which were tested, laid about 85 eggs each during the month following emergence from the pupa, six or seven days elapsing after emergence before the first oviposition. In the middle of the winter, oviposition (with later generations) became very irregular in spite of the temperature and humidity remaining constant. The adults, which were comparable to those of the natural habitat, were fed on sugar solution, honey and fruit juice. One bred out as a gynandromorph.When given an abundant supply of larvae of laboratory bred Aëdes aegypti, the life-cycle of M. brevipalpis was normally : egg (incubation), less than two days ; larva, 11–20 days (average 14·5 days) ; pupa, five days. This does not include a small number of exceptional cases in which the life as a fully grown larva was abnormally prolonged (in one case nearly four months) for reasons which are not absolutely clear. The larvae killed from 100 to 200 or more Aëdes larvae during the normal larval life, but many of these were not eaten when the brevipalpis were in the late fourth instar. By a special technique they were also induced to eat dead tissues including minced pork brawn, minced maggots and minced flies. Except for the latter these were not satisfactory foods although there was slow development.Fourth-instar larvae were kept out of water for three to four weeks (without food), in a damp atmosphere, and afterwards when fed most of them developed normally, but pupation was sometimes suspended for a considerable time. They have been sent by post (out of water) in tubes with damp cotton wool and filter paper.The egg differed from that of other Megarhinus species in having a crown of projections at one end with a cup-like structure in the centre. The exochorion had roughly hexagonal cells but without numerous tubercles as in other species.First-instar larvae remained in the egg-shell after hatching when the eggs-were out of water but on a damp surface and in a saturated atmosphere. They survived like this for up to six days or about the same time as the larvae survived in tap water if there was no food. When liberated in water the head of the first-instar larva was comparatively small with the mouth parts folded in. Within two hours of liberation in water the head enlarged considerably and the mouth parts came into position ; the larva was then ready to catch its Culicine prey. When in water containing dead leaves, these larvae survived from a few days to over four weeks and some grew to the third instar without any Culicine food.Cannibalism was investigated. Fourth-instar larvae did not attack each other readily ; they devoured smaller larvae of their own species and small to medium size larvae resorted to cannibalism, particularly in the absence of Culicine prey. There was evidence that fourth-instar Aëdes aegypti occasionally ate first-instar Megarhinus.The discussion traces attempts which have been made in certain Pacific islands, notably Hawaii and Fiji, to use Megarhines for biological control of disease-carrying mosquitos. M. brevipalpis has a shorter life-cycle than the species introduced into these islands and the conclusion reached is that laboratory breeding, to enable large numbers to be released in certain areas, would be a suitable adjunct to a programme of general control, in this part of the world. Airmail consignments of larvae are being sent to Hawaii with the object of starting a laboratory colony there.

Studies on the biology of the palm aphid, Cerataphis variabilis (Homoptera: Pemphigidae), on Raphia hookeri–1: Developmental period of the immatures, fecundity and longevity of the apterous adults

1985 ◽  
Vol 6 (2) ◽  
pp. 177-181 ◽  
Author(s):  
D. A. Enobakhare
Keyword(s):  
Relative Humidity ◽  
Developmental Period ◽  
Fourth Instar ◽  
First Instar ◽  
Raphia Hookeri

AbstractThe biology of the aphid, Cerataphis variabilis H.R.L., on Raphia hookeri Mann & Wendl., was studied in the laboratory and the field using a ‘clip-on’ cage and a sleeve cage. The first instar lasted 5.1 days. The second and third instars each lasted 2.45 days, while the fourth instar lasted 2.4 days. The total developmental period of the nymphs was 11.3 days at 26.4 ± 1.43°C and r.h. 83 ± 1.46%; 11.6 days at 26.4 ± 1.63°C and r.h. 85 ± 1.19%; 12.9 days at 27.9 ± 1.04°C and r.h. 75.5 ± 1.64%; 12.95 days at 27.8 ± 0.33°C and r.h. 69 ± 1.23%; 15 days at 21.4 ± 0.58°C and r.h. 45 ± 1.77%. These periods were significantly different at 5% level (LSD = 0.59 days). The higher the temperature and relative humidity the shorter the developmental period (with temperature: r = −0.69, 20.8–28.9°C; r.h.: r = −0.97, 43.2–86.2%). The number of progeny per adult ranged from 54 to 60 in a period of 28–31 days. The longevity ranged from 31 to 34 days.

scholarly journals Amblyomma nodosum (Neumann, 1899): observations on life cycle under laboratory conditions

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
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Environmental Conditions ◽  
Oryctolagus Cuniculus ◽  
Adult Stage ◽  
Immature Stages ◽  
Experimental Conditions ◽  
Laboratory Conditions ◽  
Natural Hosts

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.

Growth and development of larvae and adults of Tipula sacra Alexander (Insecta: Diptera) in a series of abandoned beaver ponds

1976 ◽  
Vol 54 (2) ◽  
pp. 266-284 ◽  
Author(s):  
G. Pritchard
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Growth And Development ◽  
Adult Emergence ◽  
Head Capsule ◽  
Fourth Instar ◽  
Beaver Ponds ◽  
The Third ◽  
First Instar ◽  
Two Peaks

Collections of all stages of the crane fly, Tipula sacra have been made over a period of years from a series of abandoned beaver ponds in the Kananaskis Valley, Alberta. The growth of larvae was followed by head-capsule measurements and weights. Eggs hatch within a month; first-instar larvae grow rapidly and enter the second instar after a few weeks. The second instar may last for 3 months and the third instar usually lasts for 6 months, including the first winter. Most larvae spend almost a full year in the fourth instar and overwinter for a second time. However, there was much variation in growth rate within the population. Adult emergence curves were consistent in form in 4 years. Each spanned a period of just over 2 months, although individual adults lived for only a few days. These curves snowed two peaks, the second of which contained 15–20% of the year's emergents. These two groups may represent different cohorts that have grown at different rates, suggesting that the life history may be semivoltine or univoltine. The sex ratio changes from about 1:1 in the third instar to 2:1 in favor of males in the late fourth instar, pupa, and adult.

Observations on the biology of Lycts Brunneus (Steph.)

1953 ◽  
Vol 1 (1) ◽  
pp. 102 ◽  
Author(s):  
FJ Gay
Keyword(s):  
Heat Treatment ◽  
Life Cycle ◽  
Relative Humidity ◽  
Sex Ratio ◽  
Moisture Content ◽  
Incubation Period ◽  
Developmental Period ◽  
Wood Moisture Content ◽  
Optimal Conditions ◽  
Wood Moisture

An account is given of certain aspects of the biology of Lyctus brunneus (Steph.). Female beetles are able to oviposit within 24 hr. after emerging from infested timber and deposit an average of more than 70 eggs per female over a period of 1-2 weeks. Eggs are deposited at depths of 1.0-6.5 mm. in the wood vessels, preferentially from a transverse surface, but also through radial and tangential faces. The incubation period of the eggs ranges from about 1 week at 26�C, to 3 weeks at 15�C. The egg-adult developmental period ranges from 4 months at 26�C. to 16 months or more at 15�C. Under optimal conditions of temperature, relative humidity (and hence wood moisture content), and nutrition, the life cycle may be as short as 2 months. The sex ratio of L. brunneus is 1 : 1 and the adult beetles live from 2.5 to 7 weeks, depending upon the temperature, females being somewhat longer-lived than males. The larvae of L. brunneus are somewhat more resistant to heat treatment than are the eggs, but one 1/2hr. exposure to 50�C. is completely lethal to both stages.

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