Comparative studies on populations ofPauesia juniperorum(Hymenoptera: Braconidae), a biological control agent forCinara cupressivora(Hemiptera: Aphididae)

2005 ◽  
Vol 95 (6) ◽  
pp. 597-603 ◽  
Author(s):  
M.T.K. Kairo ◽  
S.T. Murphy

AbstractPauesia juniperorum(Starý), a solitary endoparasitoid which attacks severalCinaraspp. in the subgenusCupressobium, was introduced into Africa for the control of the cypress aphidCinara cupressivoraWatson & Voegtlin (previously identified asCinara cupressi(Buckton)) and is now established. Data on its biology including a comparison of populations from different hosts and geographical locations are presented. From the UK this consisted of populations reared fromCinara cupressivora, Cinara fresaiBlanchard andCinara juniperiDe Geer, and from France,Cinara?fresai. Between different populations, the duration of development varied within a narrow range (15.5–18.1 days) at 22°C. Data on duration of development over a range of temperatures (15–26°C) for two populations, from the UK and France ranged between 14.0–31.4 days for males and 14.7–32.8 days for females. The threshold temperature for development was 6.2°C and 4.1°C for the populations from the UK and France, respectively. The mean egg load for different populations ranged between 46.4 and 78.5 eggs. The host species had a significant effect on egg load which was directly related to size of the respective host aphids. The lowest egg load was recorded on specimens reared fromC. cupressivorawhich was the smallest aphid. The population from the UK had a higher intrinsic rate of increase (0.232) than the one from France (0.207).

2021 ◽  
Vol 26 (2) ◽  
pp. 496-508
Author(s):  
Firdevs Ersin ◽  
Ferit Turanli ◽  
Ibrahim Cakmak

Typhlodromus recki (Acari: Phytoseiidae) was collected from aubergines, pepper, black nightshade and jimsonweed plants infested with spider mites from a pesticide-free vegetable garden in Denizli, Turkey. The biology and life table parameters for T. recki feeding on Tetranychus urticae (Acari: Tetranychidae) at different temperatures (15, 20, 25, 30 and 35 °C) were determined. The results showed that total preadult periods of T. recki at 15, 20, 25, 30 and 35 °C were 19.6±0.51, 9.4±0.16, 7.6±0.14, 5.7±0.14 and 4.5±0.08 days, respectively. The longest oviposition period was 23.5 days at 20 °C. Total fecundity of T. recki significantly differed between the constant temperatures and the highest was observed at 20 °C (28.6 eggs/female) and 25°C (23.5 eggs/female). Although females survived for 26 days at 35 °C, only four females laid eggs for 1 day. Thus, 35 °C is not suitable for the reproduction of T. recki. Total longevity of female was the longest at 15°C (59.5 days) and 20 °C (51.3 days) whereas male total longevity was the longest at 15°C (53.2 days). The intrinsic rate of increase (r) and finite rate of increase (λ) were numerically the highest at 30 °C (0.17 and 1.18 d-1), but there was no statistical difference observed between 25 and 30 °C for both r and λ values. The net productive rate was significantly highest at 20, 25 and 30 °C. The longest mean generation time occurred at 15 °C (42.6 days) and the shortest was at 35 °C (8.0 days). After some field trials, Typhlodromus recki could potentially be considered in the biological control agent of T. urticae.


Insects ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 475
Author(s):  
Sheng Yin Wang ◽  
Bo Li Wang ◽  
Gai Lan Yan ◽  
Yan Hong Liu ◽  
Da Yu Zhang ◽  
...  

Aphelinus asychis, a polyphagous parasitoid, has been widely used as an efficient biological control agent against the aphid Myzus persicae. Aiming to evaluate the influence of temperature on the biological characteristics and control potential of A. asychis for M. persicae, we compared the life table parameters and control potential of A. asychis, which included the developmental time, longevity, fecundity, intrinsic rate of increase (r), and finite killing rate (θ). The results showed that increasing the temperature significantly decreased the developmental time and longevity of A. asychis. The r at 24 (0.2360 d−1) and 28 °C (0.2441 d−1) were significantly greater than those at 20 (0.1848 d−1) and 32 °C (0.1676 d−1). The θ at 24 (0.4495), 28 (0.5414), and 32 °C (0.4312) were also significantly greater than that at 20 °C (0.3140). The relationship between population fitness (r and θ) and temperature followed a unary quadratic function (R2 > 0.95). The temperatures for the expected maximum intrinsic rate of increase (rmax) and the maximum finite killing rate (θmax) were 25.7 and 27.4 °C, respectively. In conclusion, A. asychis could develop and produce progenies within the temperature range of 20–32 °C, and its control efficiency for M. persicae at 24, 28, and 32 °C was greater than that at 20 °C. The most suitable temperature range for controlling M. persicae with A. asychis in the field might be between 25.7 and 27.4 °C.


Author(s):  
Yingchao Ji ◽  
Guohua Li ◽  
Chenggang Zhou ◽  
Shuyan Yin

Abstract Temperature is one of the main factors affecting insect growth, development and reproduction. The effects of temperatures (10, 15, 20, 25 and 30°C) on the development and reproduction of Cinara cedri Mimeur (Hemiptera: Aphidoidea: Lachnidae) fed on Cedrus deodara (Roxb.) G. Don were evaluated in this study. With the increase of temperature from 10 to 30°C, the development duration at different development stages gradually shortened. There was a significant positive correlation between the developmental rates and temperature, following a quadratic regression model. The lower developmental threshold temperature (C) and effective accumulated temperatures (K) for completing a generation were 4.13°C and 263.4 degree-days, respectively. The highest fecundity was observed at 20°C with 25.74 first-instar nymphs/female. Both the highest intrinsic rate of increase (r, 0.11 ± 0.03) and net reproduction rate (R0, 19.06 ± 2.05) were observed at 20°C, whereas the lowest values of r (0.05 ± 0.01) at 10°C and R0 (5.78 ± 0.88) at 30°C were observed. The results suggest that temperature significantly affects the biology of C. cedri and the optimal temperature for its development is 20°C.


Author(s):  
Jie Su ◽  
Fang Dong ◽  
Si-min Liu ◽  
Yan-hui Lu ◽  
Jian-ping Zhang

Abstract The predatory mite, Neoseiulus bicaudus (Wainstein), is a potential biological control agent against spider mites and thrips. The objective of this experiment was to compare the effects of three diets on the life table of N. bicaudus. The three diets were 1) Tetranychus turkestani (Ugarov & Nikolskii) (Acari: Tetranychidae), the natural prey of N. bicaudus; 2) Tyrophagus putrescentiae (Schrank) (Acari: Acaridae), an alternative prey; and 3) artificial diet primarily consisting of decapsulated shrimp cysts, egg yolk, and honey. The computer simulation was used to project the population growth of N. bicaudus fed on different diets. The preadult developmental time (3.83 d) of N. bicaudus was shortest, and the intrinsic rate of increase (r = 0.2782 d−1) and the net reproductive rate (R0 = 18.98 offspring) were highest when reared on the alternative prey Ty. putrescentiae. The total development time (7.37 d) was longest, and the population parameters were the lowest (r = −0.0081 d−1, R0 = 0.85 offspring) when N. bicaudus was reared on artificial diet. The population projection showed that the population of N. bicaudus reared on Ty. putrescentiae could increase fast. Our results showed that the Ty. putrescentiae was the most suitable prey for mass rearing of N. bicaudus. The artificial diet could not support the N. bicaudus population and needs to be improved.


Insects ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 482
Author(s):  
Modesto del Pino ◽  
Juan Ramón Gallego ◽  
Estrella Hernández Suárez ◽  
Tomás Cabello

Trichogramma achaeae Nagaraja and Nagarkatti (Hymenoptera: Trichogrammatidae) is currently used as biological control agent for several lepidopteran pests. Knowledge of thermal requirements is essential to optimize its rearing procedures and inundative releases. The biological characteristics and two-sex life table parameters of T. achaeae were determined at five constant temperatures (15, 20, 25, 30, and 35 °C) using Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs. T. achaeae was able to develop and survive from 15 °C to 30 °C, but not at 35 °C. Temperature significantly affected the preadult development time and adult longevity, decreasing when temperature increased from 15 °C to 30 °C. Temperature significantly altered the sex ratio, being female biased between 15 °C and 25 °C. Age-stage, two-sex life table analysis indicated that net reproductive rate (R0) was highest at 20 °C. Both the intrinsic rate of increase (r) and finite rate of increase (λ) increased with increasing temperature, while the mean generation time (T) decreased significantly. In addition, functional response of T. achaeae was studied, being significantly affected by temperature and host egg density, displaying a Holling type-I at 15 °C and a Holling type-II at 25 °C. The relevance of these results is discussed for the use of T. achaeae as biological control agent.


2019 ◽  
Vol 112 (5) ◽  
pp. 2103-2108
Author(s):  
Dinarte Gonçalves ◽  
da Uemerson Silva Cunha ◽  
Priscila de Andrade Rode ◽  
Maicon Toldi ◽  
Noeli Juarez Ferla

Abstract Schizotetranychus oryzae Rossi de Simons attains pest level in rice crops. This study aimed to evaluate the biological features of Neoseiulus californicus (McGregor) feeding on S. oryzae on leaves of flooded rice. We also evaluated N. californicus behavior in response to S. oryzae and conspecific cues. Thirty-two eggs were individually placed in arenas on rice leaves and fed on S. oryzae for the biological test. Three cultivars were used to test the behavior of N. californicus in response to S. oryzae and conspecific cues. The intrinsic rate of increase (rm) of the predator feeding on S. oryzae was 0.21 female/female/day. Schizotetranychus oryzae was considered a suitable prey for N. californicus under laboratory conditions. The results obtained in behavioral tests showed that N. californicus preferred laying eggs on leaves uninfested by S. oryzae and it did not show oviposition preference in arenas with conspecific predator cues. This predator was found in all rice cultivation areas in the state of Rio Grande do Sul, Brazil. Neoseiulus californicus proved to be a control agent for S. oryzae.


1996 ◽  
Vol 86 (1) ◽  
pp. 67-72 ◽  
Author(s):  
Parviz Shishehbor ◽  
Paddy A. Brennan

AbstractSelected life history characteristics of Encarsia formosa Gahan parasitizing the castor whitefly, Trialeurodes ricini (Misra) were studied at three constant temperatures (20, 25 and 30°C). Egg-to-adult developmental time decreased from 32 days at 20°C to 13 days at 30°C. An average of 241 day-degrees was required to complete development above the lower threshold temperature (12°C). Juvenile mortality was 34, 40 and 47% at 20, 25 and 30°C, respectively. Mean longevity of E. formosa ranged from 7.7 days at 20°C, to 2.6 days at 30°C. Mean total fecundity ranged from 18 to 36 eggs/female. Intrinsic rate of increase (rm) increased with temperature from 0.065/day at 20°C to 0.169/day at 30°C. Generation times decreased from 37 to 14.5 days with increasing temperature.


1981 ◽  
Vol 113 (1) ◽  
pp. 65-71 ◽  
Author(s):  
H. J. Herbert

AbstractDevelopment of the European red mite, Panonychus ulmi (Koch), in Nova Scotia was studied at three constant temperatures to construct a life table and establish the intrinsic rate of development. The threshold temperature for development was 10.6°C. The duration from the beginning of the egg stage to adult for females was 31.2, 20.5, and 14.0 days and for males 21.9, 19.6, and 12.8 days at 15°, 18°, and 21°C, respectively. The duration in degree-days above 10.6°C for females was 137.3, 151.7, and 145.2 and for males 128.0, 144.9, and 133.1 at the same three temperatures. The duration of the preoviposition period decreased, duration of the oviposition period remained constant, and the number of eggs laid increased with temperature. Life tables were constructed at 15°, 18°, and 21°C; the intrinsic rates of increase were 0.56,.092, and.134; net reproduction rates 10.06, 13.50, and 17.37; and mean generation times were 41.4, 28.3, and 21.3 days, respectively.


Author(s):  
Luis Carlos Ramos Aguila ◽  
Mubasher Hussain ◽  
Wei Huang ◽  
Lijin Lei ◽  
Bamisope Steve Bamisile ◽  
...  

Abstract Tamarixia radiata Waterson (Hymenoptera: Eulophidea) is the principal natural enemy used for the control of the major citrus pest Diaphorina citri Kuwayama (Hemiptera: Liviidae). In this study, we collected the life-history data of T. radiata at four different temperatures (20, 27.5, 30, and 35°C) and analyzed them by using the age-stage, two-sex life table. The longest preadult developmental time (16.53 d) was observed at 20°C, whereas the shortest one was 7.29 d at 35°C. The preadult development rate was well-fitted to a linear equation. The lower threshold temperature (T0) was 7.85°C and the thermal summation (K) was 193.36 degree-day. The highest fecundity (F) was 322.7 eggs per female was at 27.5°C, whereas the lowest one was 10.8 eggs per female at 35°C. The net reproductive rate (R0) were 70.97, 169.42, 55.70, and 3.25 offspring at 20, 27.5, 30, and 35°C, respectively; the intrinsic rate of increase (r) were 0.1401, 0.3167, 0.3517, and 0.1143 d−1, respectively. The highest values of fecundity, net reproductive rate, intrinsic rate of increase, and finite rate of increase were observed at 27.5°C. The relationships among F, R0, Nf, and N in all treatments were consistent with R0=F×(Nf/N). The age of peak reproductive value was close to the total preoviposition period in all treatments. Population projections based on the age–stage, two-sex life table showed the dynamics of stage structure and its variability. Faster population growth was observed at 27.5 and 30°C.


Sign in / Sign up

Export Citation Format

Share Document