scholarly journals Reproductive parameters and longevity of Gryon gallardoi (Brethes) (Hymenoptera: Scelionidae) parasitizing Spartocera dentiventris (Berg) (Hemiptera: Coreidae) eggs

2006 ◽  
Vol 66 (1a) ◽  
pp. 19-24 ◽  
Author(s):  
C. R. Canto-Silva ◽  
H. P. Romanowski ◽  
L. R. Redaelli
Keyword(s):  
Sex Ratio ◽  
Oviposition Period ◽  
Reproductive Parameters ◽  
Laboratory Conditions ◽  
Good Potential ◽  
Reproductive Capability ◽  
Honey Solution

The fecundity, daily progeny and longevity of Gryon gallardoi (Brethes) (Hym.; Scelionidae) were determined under laboratory conditions, using Spartocera dentiventris (Berg) (Hem.; Coreidae) eggs as host. Nineteen G. gallardoi females and 34 males were reared at 25 ± 1 °C, with a 12 h photophase, fed on a 10% aqueous honey solution and provided with 25-30 S. dentiventris eggs daily. The average pre-oviposition period was 1.3 ± 0.35 days, although some females began laying from the day of emergence. On average, oviposition lasted for 10.1 ± 1.74 days, reaching a peak on the second day, with 67.5 ± 11.29 eggs laid. The post-oviposition period was short (2.4 ± 0.48 days). G. gallardoi females lived significantly longer than males: 13.7 ± 1.94 and 10.6 ± 1.78 days, respectively. The overall sex ratio was 0.79. The results reported here on the reproductive capability of the species suggest it may have a good potential as an agent for the control of S. dentiventris.

scholarly journals Prey quantity affects development, survival and reproductive attributes of Coccinella transversalis Fabricius, 1781 under laboratory conditions

2020 ◽  
Vol 4 (1) ◽  
pp. 8-15
Author(s):  
Mahadev Bista
Keyword(s):  
Mass Culture ◽  
Growth Index ◽  
Adult Emergence ◽  
Developmental Rate ◽  
Reproductive Rate ◽  
Oviposition Period ◽  
Reproductive Parameters ◽  
Laboratory Conditions ◽  
Aphid Prey ◽  
Coccinella Transversalis

This study assessed development, survival and reproductive parameters of a ladybird beetle, Coccinella transversalis Fabricius, 1781 on different quantities (viz. scarce, optimum and abundant) of the bean aphid prey, Aphis craccivora under laboratory conditions (27 ±1°C; 65 ±5% relative humidity and 14 light: 10 dark hours photoperiod). The pre-oviposition period was the shortest (6.40 ±0.40 days) on abundant prey and longest (9.20±0.49 days) on scarce prey. The oviposition period significantly increased with increasing prey quantity, being longest (55.10 ±1.75 days) on abundant prey and shortest (38.50 ±2.14 days) on scarce prey. Lifetime fecundity and egg viability were recorded the highest (1604.10 ±45.61 eggs and 90.82 ±0.80%, respectively) on abundant diet and lowest (794.60 ±30.84 eggs and 82.72 ±0.67%, respectively) on scarce diet. Reproductive rate, reproductive time ratio, longevity of male and female were all highest, i.e. 29.20 ±0.61 egg/day, 3.70 ±0.26, 65.80 ±1days and 70.30 ±1.30 days, respectively on abundant diet. These parameters were lowest, i.e. 20.90 ±0.83 eggs/day, 1.95 ±0.16, 58.80 ±1.60 days and 56.20 ±1.75 respectively on scarce diet. Development was fastest on abundant prey followed by optimum and slowest on scarce prey. Percentage pupation, percent adult emergence, developmental rate, growth index and generation survival were all highest, i.e. 84.00 ±3.68%, 79.00 ±4.09%, 0.077 ±0.00 day-1, 3.50 ±0.19 day-1, 0.54 ±0.05, respectively when larvae were reared on abundant prey. The same parameters were lowest, i.e. 65.00 ±04.79%, 57.00 ±4.99%, 0.062 ±0.001 day-1, 10.46 ±0.11 day-1, 0.25 ±0.0, respectively on scarce prey. It may therefore be concluded that the availability of abundant prey enhances developmental and reproductive parameters of C. transversalis, and abundant diet of aphid prey may be used for better mass culture of ladybird beetles in laboratories for augmentative biological control of aphids.

Effect of Constant and Fluctuating Temperature on the Development, Reproduction, Survival, and Sex Ratio of Phenacoccus solenopsis (Hemiptera: Pseudococcidae)

2020 ◽  
Vol 49 (3) ◽  
pp. 553-560
Author(s):  
Muhammad Saad Waqas ◽  
Lulu Lin ◽  
Ali Ahmed Zaky Shoaib ◽  
Xinlai Cheng ◽  
Qianqian Zhang ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Constant Temperature ◽  
Oviposition Period ◽  
Adult Longevity ◽  
Developmental Duration ◽  
Phenacoccus Solenopsis ◽  
Fluctuating Temperature ◽  
Laboratory Conditions ◽  
Preoviposition Period ◽  
Fluctuating Temperatures

Abstract Effects of temperature on the development, survival, reproduction, longevity and sex ratio of the cotton mealybug, Phenacoccus solenopsis Tinsley, was assessed at five constant temperatures ranging from 20 to 35°C and five fluctuating temperatures ranging from 15 to 40°C under laboratory conditions. Results showed that nymphal development duration, preoviposition period, oviposition period, fecundity, and adult longevity were reduced significantly with increasing temperature until 30°C, but developmental duration of third female nymphal instar and female adult longevity was longer at 35°C than 30°C, and no males could emerge from pupae at the constant temperature 35°C. Fluctuating temperature, in general, significantly accelerated the nymphal developmental duration, prolonged preoviposition period, shortened oviposition period, reduced fecundity, lowered the survival rate of nymphs, and decreased adult longevity of males and females compared to their mean corresponding constant temperature. Overall, it is suggested that one should be prudent when applying the obtained results under constant and fluctuating temperatures under laboratory conditions.

scholarly journals Reproductive Biology of Round Sardinella (Sardinella Aurita) (Valenciennes, 1847) in Senegalese Coastal Waters

2018 ◽  
Vol 9 (1) ◽  
pp. 31
Author(s):  
Ismaïla NDIAYE ◽  
Alassane SARR ◽  
Alioune FAYE ◽  
Modou THIAW ◽  
Malick DIOUF ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Reproductive Biology ◽  
Coastal Waters ◽  
Sexual Maturity ◽  
Reproductive Parameters ◽  
Monthly Variation ◽  
Relative Fecundity ◽  
The Mean ◽  
Sardinella Aurita ◽  
Somatic Index

In this study, a total of 1068 specimens Sardinella aurita of which 553 females and 515 males were examined. The objectif of this study was to determine the reproductive parameters of Sardinella aurita. The sex ratio was significantly in favor of females (55%). The size at first sexual maturity was estimated at 18.9 cm for females and 18.0 cm for males. The monthly variation of sexual maturity stages and gonado-somatic index (GSI) allowed to locate the reproduction periods from February to June and from September to December. The mean absolute fecundity was estimated at 110.794 ± 7582 oocytes whereas relative fecundity was about 422 ± 26 oocytes per gram of female.

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 ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Sex Ratio ◽  
Light Regime ◽  
Climatic Chamber ◽  
Offspring Number ◽  
Diatraea Saccharalis ◽  
Laboratory Conditions ◽  
Glass Tubes

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.

scholarly journals Reproductive biology and embryonic development of Centroscymnus coelolepis in Portuguese mainland waters

2003 ◽  
Vol 60 (6) ◽  
pp. 1335-1341 ◽  
Author(s):  
Ana Veríssimo ◽  
Leonel Gordo ◽  
Ivone Figueiredo
Keyword(s):  
Sex Ratio ◽  
Embryonic Development ◽  
Reproductive Biology ◽  
Sexual Maturity ◽  
Sampling Period ◽  
Yolk Sac ◽  
Pregnant Female ◽  
Reproductive Parameters ◽  
Reproductive Characteristics ◽  
Total Length

Abstract A total of 871 females (76–122 cm) and 86 males (68–100 cm) of Centroscymnus coelolepis caught in Portuguese mainland waters were examined for reproductive characteristics. One hermaphroditic individual of 95 cm was found. Males were few in numbers and dominated by immature specimens. Female length at first sexual maturity was 98.5 cm. Mean ovarian and uterine fecundity were 13.2 oocytes per female and 9.9 embryos per pregnant female, respectively. Total length of embryos with completely absorbed external yolk sacs ranged between 233 and 300 mm. Sex ratio (F/M) of embryos with completely absorbed external yolk sac was 0.9. All stages of reproduction were found during the 12-month sampling period. Results were compared with those from other regions. A hypothesis is formulated on the existence of several regional populations based on morphometric and reproductive parameters observed in different areas.

Laboratory studies on the life-history of Valanga nigricornis nigricornis (Burm.) (Orth., Acrididae)

1971 ◽  
Vol 60 (3) ◽  
pp. 439-446 ◽  
Author(s):  
M. L. Kok
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Life Cycle ◽  
External Genitalia ◽  
Oviposition Period ◽  
Growth Stages ◽  
Laboratory Studies ◽  
Laboratory Conditions ◽  
History Of

Descriptions are given of all growth stages of Valanga nigricornis nigricornis (Burm.). The hopper instars (normally six in the male and seven in the female) could be distinguished by the development of the external genitalia. Under laboratory conditions (mean 27–9°C and 80% r.h.), the life-cycle was completed in 6½–8½ months, and the females had a mean fecundity of 158. Crowding slowed the growth rate of the adults, extended the pre-oviposition period from 60 to 65 days at 30–9°C and reduced fecundity. It is concluded that the low fecundity and slow life-cycle preclude the possibility of the species becoming a widespread pest.

DEVELOPMENT OF TIPHODYTES GERRIPHAGUS (HYMENOPTERA: SCELIONIDAE) IN LIMNOPORUS DISSORTIS EGGS (HEMIPTERA: GERRIDAE)

1999 ◽  
Vol 131 (2) ◽  
pp. 219-228 ◽  
Author(s):  
João M. Sousa
Keyword(s):  
Sex Ratio ◽  
Larval Stage ◽  
Host Feeding ◽  
Larval Instars ◽  
Pupal Period ◽  
Laboratory Conditions ◽  
Total Length ◽  
Preimaginal Development ◽  
First Instar ◽  
Mandible Length

AbstractInvestigations of preimaginal development in Tiphodytes gerriphagus Marchal reveal two larval instars, based on counting exuviae and comparing mandible length during development within Limnoporus dissortis Drake & Harris eggs. Tiphodytes gerriphagus eggs are stalked, as is typical of scelionids, and are 282.6 ± 3.48 μm (mean ± SE) long. The chorion ruptures at 8–9 h postoviposition and releases a nonfeeding embryo into the host. Feeding begins at 18–20 h postoviposition, after the embryonic cuticle is shed and a fully differentiated and active larva is released. The first larval stage is teleaform and lasted up to 5 days postoviposition, and its total length increased from 183.6 ± 3.35 to 517.0 ± 14.67 μm. The second larval stage is hymenopteriform and lasted from 5 to 13 days postoviposition, and grew from 920.2 ± 24.65 to 1352.4 ± 11.89 μm total length before pupating. The pupal period lasted about 11 days, with male pupae being shorter and thinner than female pupae. These findings differ from previous descriptions of T. gerriphagus, and it is suspected that the first instar was mistakenly divided into two stadia. The sex ratio under laboratory conditions was female biased (22% males), and males were smaller but did not emerge significantly earlier than females.

scholarly journals Caractérisation de la reproduction des cobayes locaux (Cavia porcellus L.) élevés à Kipushi et Lubumbashi (RDC)

2020 ◽  
Vol 43.2 ◽  
pp. 7415-7427
Author(s):  
Kampemba M F ◽  
Bilolwa B P ◽  
Ntemunyi N C ◽  
Mwangomb K D
Keyword(s):  
Sex Ratio ◽  
Guinea Pigs ◽  
Growth Characteristics ◽  
Great Variability ◽  
Average Weight ◽  
Cavia Porcellus ◽  
Reproductive Parameters ◽  
Individual Weight ◽  
Average Individual

L’objectif de ce travail était d’étudier les caractéristiques de reproduction et de croissance des cobayes locaux. Soixante- six (66) cobayes ont été répartis en 2 lots (Lubumbashi et Kipushi) de 30 femelles subdivisées par lot de dix(10) élevés dans une cage de 1 m2 et 6 mâles avec un sex-ratio de 1 mâle contre 10 femelles et les saillies naturelles. Les résultats obtenus ont montré que le taux fertilité était élevé pour les femelles de Kipushi (86,67%) par rapport à celui enregistré à Lubumbashi (80,00%). Et le poids des femelles à la mise-bas et au sevrage n’était pas influencé par leur origine. Au niveau de la portée à la naissance ; Lubumbashi a présenté un nombre élevé (58%) que Kipushi (53%) pour des nés vivant. Par conséquent, le poids moyen individuel à la naissance (70,4g) le poids moyen individuel au sevrage (167,4g) le poids moyen par portée à la naissance 71,3g et au sevrage 168,03g étaient supérieures pour les animaux de Kipushi (p˂0,05). Alors que la portée au sevrage, le nombre de petits par sevrage était semblable entre sites (P˃ 0,05). En plus, la productivité numérique et pondérale était élevée pour les femelles de Kipushi (1,57) et faible pour celles de Lubumbashi (1,17). L’évolution du poids des cobayes variaient en fonction du site. Ces résultats sur les paramètres de reproduction dévoilent l’existence d’une grande variabilité entre ces deux populations locales, ce qui crée une occasion pour l’amélioration génétique des cobayes locaux. Characterization of the reproduction of local guinea pigs (Cavia porcellus L.) raised in Kipushi and Lubumbashi (DRC) ABSTRACT The objective of this work was to study the reproductive and growth characteristics of local guinea pigs. Sixty-six (66) guinea pigs were divided into 2 lots (Lubumbashi and Kipushi) of 30 females subdivided by lot of ten (10) reared in a 1 m2 cage and 6 males with a sex ratio of 1 male versus 10 females and natural projections. The results obtained showed that the fertility rate was high for Kipushi females (86.67%) compared to that recorded in Lubumbashi (80.00%). Moreover, the weight of the females at birth and at weaning was not influenced by their origin. At the level of the litter at birth, Lubumbashi presented a higher number (58%) than Kipushi (53%) for born babies. Therefore, the average individual weight at birth (70.4g) the average individual weight at weaning (167.4g) the average weight per litter at birth 71.3g and at weaning 168.03g were higher for the Kipushi animals (p˂0,05). While the litter at weaning, the number of pups per weaning was similar between sites (P˃ 0.05). In addition, numerical and weight productivity was high for Kipushi females (1.57) and low for Lubumbashi females (1.17). The evolution of the weight of the guinea pigs varied according to the site. These results on reproductive parameters reveal the existence of great variability between these two local populations, which creates an opportunity for the genetic improvement of local guinea pigs.

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