EFFECTS OF CONSTANT TEMPERATURE, RELATIVE HUMIDITY, AND SIMULATED RAINFALL ON DEVELOPMENT AND SURVIVAL OF THE SPRUCE SPIDER MITE (OLIGONYCHUS UNUNGUIS)

1983 ◽  
Vol 115 (1) ◽  
pp. 93-105 ◽  
Author(s):  
John V. Boyne ◽  
Fred P. Hain
Keyword(s):  
Relative Humidity ◽  
Intrinsic Rate ◽  
Developmental Time ◽  
Reproductive Rate ◽  
Natural Increase ◽  
Simulated Rainfall ◽  
Net Reproductive Rate ◽  
Fraser Fir ◽  
Oligonychus Ununguis ◽  
Rate Of Increase

AbstractExperiments were conducted on Fraser fir, Abies fraseri (Pursh) Poir, seedlings or cut terminals. Results indicate that Oligonychus ununguis (Jacobi) responds most favorably to temperatures approximating 26 °C and to relative humidity levels approaching 50 to 60%. Developmental time, time to 50% mortality, net reproductive rate, mean generation time, intrinsic rate of natural increase, finite rate of increase, and days for populations to double were computed for each temperature and relative humidity regime. Simulated rainfall severely limits population density on Fraser fir seedlings.

scholarly journals A life table analysis to evaluate biological control of banks grass mite using the predatory mite, Galendromus flumenis (Acari: Phytoseiidae)

2017 ◽  
Vol 22 (1) ◽  
pp. 7 ◽  
Author(s):  
Fatemeh Ganjisaffar ◽  
Thomas M. Perring
Keyword(s):  
Biological Control ◽  
Growth Parameters ◽  
Intrinsic Rate ◽  
Developmental Time ◽  
Predatory Mite ◽  
Reproductive Rate ◽  
Intrinsic Rate Of Increase ◽  
Net Reproductive Rate ◽  
Rate Of Increase ◽  
Banks Grass Mite

The predatory mite, Galendromus flumenis (Chant) (Acari: Phytoseiidae), has shown promising traits for biological control of Banks grass mite, the major pest of date palms in California. In the present study, reproduction and population growth parameters of G. flumenis on Banks grass mite eggs were studied at 34ºC, 50±10% RH and a photoperiod of 16: 8 (L: D) hours. 100 percent of eggs hatched and 63.5 percent of the emerged larvae survived to adulthood. The total immature developmental time was 5.7 and 5.5 days for females and males, respectively. The sex ratio of G. flumenis was 0.70 (females/ females+ males). Mated females laid on average 1.6 eggs per day and 19.9 eggs during their mean ovipositional period of 12.5 days. The net reproductive rate (R0) was 11.5 females/ female/ generation, the intrinsic rate of increase (rm) was 0.200 females/ female/ day, the finite rate of increase (λ) was 1.222 population multiplication/ day, the mean generation time (T) was 12.2 days, and the doubling time (DT) was 3.5 days. The lower rm value of G. flumenis than that of its prey (0.24–0.48) explains why Banks grass mite escapes control by G. flumenis in field. These results suggest that augmentative release of this predator would offset the lower rm of the predator, thereby contributing to the control of Banks grass mite. Combined with the benefit of early releases determined in companion studies, future field studies with G. flumenis are being planned.

scholarly journals Resistance and tolerance of ten carrot cultivars to the hawthorn-carrot aphid, Dysaphis crataegi Kalt., in Poland

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0247978
Author(s):  
Maria Pobożniak ◽  
Małgorzata Gaborska ◽  
Tomasz Wójtowicz
Keyword(s):  
Intrinsic Rate ◽  
Reproductive Rate ◽  
Natural Increase ◽  
Reproductive Period ◽  
Field Resistance ◽  
Intrinsic Rate Of Increase ◽  
Demographic Parameters ◽  
Reproduction Rate ◽  
Net Reproductive Rate ◽  
Rate Of Increase

Damage caused to cultivated carrots by the hawthorn-carrot aphid, Dysaphis crataegi Kalt. (Hemiptera: Aphididae) is one of the factors limiting carrot production in Poland. Planting resistant and tolerant cultivars could reduce yield losses due to the damage caused by this pest. This study was conducted to evaluate the resistance and/or tolerance of 10 carrot genotypes to hawthorn-carrot aphid. Their field resistance was determined under field conditions based on five indicators, namely, mean number of alates (migrants) per plant and mean percentage of plants colonized by them, mean seasonal number of aphids per plant, mean number of aphids per plant and mean percentage of infested plants at peak abundance. Antibiosis experiments were conducted under laboratory conditions and pre-reproductive, reproductive time, fertility, and demographic parameters, represented by the net reproduction rate (Ro), intrinsic rate of increase (rm) and mean generation time (T), were calculated. Five cultivars, Afro F1, Nipomo F1, Samba F1, White Satin F1, and Yellowstone showed field resistance. Antibiosis experiments revealed significant differences among the carrot cultivars in the length of the reproductive period, female fecundity in the time equal to the pre-reproduction time, and total progeny of hawthorn-carrot aphid. The intrinsic rate of natural increase (rm) for apterous aphids varied significantly, ranging between 0.181 (Nipomo F1) and 0.343 females/female/day (White Satin F1). Additionally, the estimated net reproductive rate (R0) was the lowest on Nipomo F1, and this genotype was determined to be resistant. Our results suggest that a very high density of trichomes on the leaf petioles (71.94 trichomes/cm2) could adversely affect the feeding, bionomy, and demographic parameters of hawthorn-carrot aphid on the cultivar Nipomo F1. In addition, Napa F1 and Kongo F1 demonstrated high tolerance. Considering all the results collectively, four genotypes, Afro F1, Kongo F1, Napa F1 and Nipomo F1, were relatively resistant/tolerant to the hawthorn-carrot aphid.

Productivity of Neoseiulus bicaudus (Acari: Phytoseiidae) Reared on Natural Prey, Alternative Prey, and Artificial Diet

2019 ◽  
Author(s):  
Jie Su ◽  
Fang Dong ◽  
Si-min Liu ◽  
Yan-hui Lu ◽  
Jian-ping Zhang
Keyword(s):  
Artificial Diet ◽  
Biological Control Agent ◽  
Intrinsic Rate ◽  
Developmental Time ◽  
Reproductive Rate ◽  
Intrinsic Rate Of Increase ◽  
Alternative Prey ◽  
Net Reproductive Rate ◽  
Natural Prey ◽  
Rate Of Increase

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.

scholarly journals Interaction Between Bt-Transgenic Cotton and the Whitefly’s Parasitoid, Encarsia Formosa (Hymenoptera: Aphelinidae)

2014 ◽  
Vol 54 (3) ◽  
pp. 272-278 ◽  
Author(s):  
Solmaz Azimi ◽  
Shima Rahmani ◽  
Masoud Tohidfar ◽  
Ahmad Ashouri ◽  
Alireza Bandani ◽  
...  
Keyword(s):  
Intrinsic Rate ◽  
Developmental Time ◽  
Reproductive Rate ◽  
Intrinsic Rate Of Increase ◽  
Bt Cotton ◽  
Encarsia Formosa ◽  
Net Reproductive Rate ◽  
Preoviposition Period ◽  
Rate Of Increase ◽  
The Mean

Abstract Transgenic Bt cotton developed against lepidopteran pests may not be compatible with parasitoid of secondary pests such as Bemisia tabaci which attack many plants such as cotton. In this study, the effects of Bt cotton on the demographic parameters of Encarsia formosa, parasitoid of B. tabaci were assessed. The data were analysed using the age specific, two-sex life table parameters. The results indicated that pre-adult developmental time, the total preoviposition period (TPOP) and the adult preoviposition period (APOP) in the Bt cotton were significantly longer than in the non-Bt cotton. Also, fecundity and body size in both lines were significantly different. The fecundity was 23.64±0.73 and 43.75±0.89 eggs/females in the Bt and non-Bt cotton, respectively. All the population parameters were affected by the Bt cotton. The intrinsic rate of increase (r) was 0.15 day-1 in the non-Bt cotton but it was 0.10 day-1 in the Bt cotton. The finite rate of increase (λ) was 1.11 day-1 in the non-Bt cotton whilst it was 1.08 in the Bt cotton. The net reproductive rate (R0) in the non-Bt cotton was 36.75 but in the Bt cotton these parameters showed 19.62 offspring/individual. Also, the mean generation time (T ) in the non-Bt and Bt cotton was 22.69 and 27.79 days, respectively. The results illustrated, that although transgenic crops are effective tools for management of the target pests, they can adversely affect, either directly or indirectly, the natural enemies dependent on these plants.

Bioecology of the tea thrips, Scirtothrips bispinosus Bagnall (Thysanoptera: Thripidae) infesting tea in south India

ENTOMON ◽  
2019 ◽  
Vol 44 (3) ◽  
pp. 161-172
Author(s):  
P. Mahendran ◽  
B. Radhakrishnan
Keyword(s):  
Relative Humidity ◽  
South India ◽  
Negative Relationship ◽  
Reproductive Rate ◽  
Natural Increase ◽  
Seasonal Abundance ◽  
Maximum Temperature ◽  
Developmental Duration ◽  
Net Reproductive Rate ◽  
Rate Of Increase

Investigations were carried out on the life history and seasonal abundance of the thrips, Scirtothrips bispinosus infesting tea at Coonoor, The Nilgiris, Tamilnadu. The total developmental duration of females from egg to adult stage was 18.15±0.23, 12.55±0.15 and 10.30±0.23 days at 20, 25 and 30oC respectively. The net reproductive rate (Ro), mean generation time (Tc), intrinsic rate of natural increase (rm), finite rate of increase (ë) and weekly multiplication (Wm) rates were high at 25oC followed by 30oC and 20oC. Multiple regression analysis revealed that population density of S. bispinosus showed a negative relationship with rainfall (-0.266), maximum temperature (-38.839) and maximum relative humidity (-3.356) and positive relationship with minimum temperature (63.205), minimum relative humidity (1.686) and sunshine period (2.887). Incidence of thrips was high in the fields recovering from pruning followed by second, third and fourth year in a pruning cycle. The number of thrips per shoot was significantly higher on the plucking table when compared to the shoots present below the plucking table and side branches. In the tea plantations of South India, four species of predatory mites (Amblyseius cucumeris, A. fallacies, A. degenerans and Balaustium sp.), two species of predatory thrips (Franklinothrips vespiformis and Leptothrips mali), an anthocorid predator (Orius sp.) and one parasitoid (Trichogramma sp.) were found feeding and parasitizing on tea thrips, S. bispinosus.

scholarly journals Life History Evaluation of Ooencyrtus lucidus, a Newly Described Egg Parasitoid of Bagrada hilaris

Insects ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 292
Author(s):  
Fatemeh Ganjisaffar ◽  
Thomas M. Perring
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Intrinsic Rate ◽  
Developmental Time ◽  
Egg Parasitoid ◽  
Reproductive Rate ◽  
Intrinsic Rate Of Increase ◽  
Net Reproductive Rate ◽  
Rate Of Increase ◽  
Significant Difference

Ooencyrtus lucidus Triapitsyn & Ganjisaffar (Hymenoptera: Encyrtidae) was recently recovered from fresh sentinel eggs of Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae) in California. In the present study, life history traits of O. lucidus were studied at 26 ± 0 . 5 ∘ C, 40 ± 10 % RH, and a photoperiod of 14 L: 10 D hours. Results showed that 95.2% of the parasitized eggs yielded successful emergence of adults. The total immature developmental time was 14.27 and 13.95 days for females and males, respectively. The sex ratio of O. lucidus was 0.5 (females/offspring). Mated females laid on average 6.0 eggs per day and 222.7 eggs during their mean ovipositional period of 37.3 days. There was no significant difference in reproduction parameters between mated and non-mated females. The net reproductive rate ( R 0 ) was 103.8 females/female/generation, the intrinsic rate of increase ( r m ) was 0.171 females/female/day, the finite rate of increase ( λ ) was 1.187 population multiplication/day, the mean generation time (T) was 27.1 days, and the doubling time (DT) was 4.0 days. The highest longevity was observed in mated and non-mated females fed with honey, and they lived for 70.8 and 70.1 days, respectively. Providing females with host eggs in addition to honey, reduced their longevity by 24% in mated and 28% in non-mated individuals. Non-mated females and males deprived of honey only lived for 3.5 and 2.5 days after emergence, respectively. Our results indicate that O. lucidus has sufficient life history traits to make it a promising egg parasitoid for the biological control of B. hilaris.

scholarly journals LIFE AND FERTILITY TABLES OF Pineus boerneri ANNAND (HEMIPTERA: ADELGIDAE) ON Pinus spp. (PINACEAE)

FLORESTA ◽  
2016 ◽  
Vol 46 (2) ◽  
pp. 251
Author(s):  
Josiane Teresinha Cardoso ◽  
Sonia Maria Noemberg Lazzari
Keyword(s):  
Intrinsic Rate ◽  
Pinus Elliottii ◽  
Reproductive Rate ◽  
Natural Increase ◽  
Reproductive Capacity ◽  
Nymphal Stage ◽  
Net Reproductive Rate ◽  
Rate Of Increase ◽  
Significant Difference ◽  
Pinus Spp

Biological parameters of Pineus boerneri were evaluated in laboratory using seedlings of Pinus taeda and Pinus elliottii. The nymphs were observed along their development. The total life cycle was not significantly different on P. taeda and P. elliottii, being, respectively, 69 and 65 days. The same trend was observed for mean fecundity, being about 40 eggs/female on P. taeda and 53 on P. elliottii. However, when daily mean fecundity was considered, the difference was significant, being 1.3 eggs/female/day on P. taeda and 1.8 on P. elliottii. The nymphal mortality was greater on P. taeda (50%) than on P. elliottii (28%). These results reflected on life expectancy which was higher on P. elliottii for the nymphal stage, but for the adult stage there was no significant difference between both host plants. The intrinsic rate of natural increase and the finite rate of increase were similar, indicating that P. boerneri shows the same reproductive capacity on both hosts, despite the net reproductive rate being much greater on P. elliottii (23.8 eggs/female) than on P. taeda (15.4). The highest nymphal survival and reproductive rates on P. elliottii indicate that this host plant is more suitable for the development of P. boerneri.

scholarly journals Fertility Life Tables of Plastanoxus westwoodi (Kieffer) (Hymenoptera: Bethylidae) on Cryptolestes pusillus (Schon.) (Coleoptera: Cucujidae)

1970 ◽  
Vol 16 ◽  
pp. 25-28
Author(s):  
MM Rahman ◽  
W Islam ◽  
KN Ahmed
Keyword(s):  
Life Table ◽  
Adult Emergence ◽  
Intrinsic Rate ◽  
Reproductive Rate ◽  
Natural Increase ◽  
Life Tables ◽  
Net Reproductive Rate ◽  
Rate Of Increase ◽  
Host Instar ◽  
Cryptolestes Pusillus

Plastanoxus westwoodi is an efficient ectoparasitoid of larvae and pupae of the red flat grain beetle Cryptolestes pusillus. Fertility life tables and effects of host instar on life table parameters of P. westwoodi on C. pusillus were studied in the laboratory. Generally adult females lived for 13-16 days. Oviposition commenced on the 1st day of adult emergence and continued till death or 1-2 days before the death of a parasitoid. The intrinsic rate of natural increase (rm) was found to be 0.2291 per female per day. The net reproductive rate (R0) was 64.07; the innate capacity for increase (rc) was 0.2096. The finite rate of increase (λ) was calculated as 1.4735 per female per day, while corrected generation time (T) was computed as 18.16 days. Key words: Plastanoxus westwoodi, Cryptolestes pusillus, Oviposition, Life table, Biological control   DOI:10.3329/jbs.v16i0.3737    J. bio-sci. 16: 25-28, 2008   

scholarly journals Influence of temperature on the development, reproduction and longevity of Ceratothripoides claratris (Thysanoptera: Thripidae) on tomatoes

2004 ◽  
Vol 94 (4) ◽  
pp. 377-384 ◽  
Author(s):  
W.T.S.D. Premachandra ◽  
C. Borgemeister ◽  
A. Chabi-Olaye ◽  
H.-M. Poehling
Keyword(s):  
Adult Development ◽  
Intrinsic Rate ◽  
Reproductive Rate ◽  
Natural Increase ◽  
Net Reproductive Rate ◽  
Influence Of Temperature ◽  
Tropical Asia ◽  
Rate Of Increase ◽  
Total Fecundity ◽  
Influence Of Temperature On

AbstractCeratothripoides claratris (Shumsher) is a serious pest attacking tomatoes in Thailand. Temperature-dependent development of C. claratris was studied at seven constant temperatures, i.e. 22, 25, 27, 30, 34, 35 and 40°C. Pre-adult survivorship was greatest (95%) at 25 and 30°C and shortest at 22°C. Egg-to-adult time decreased within the range of 20 to 30°C and at 34°C it started to increase. The lower thermal threshold for egg-to-adult development was estimated at 16 and 18°C by linear regression and the modified Logan model, respectively. The optimum temperature for egg-to-adult development was estimated at 32–33°C by the modified Logan model. The influence of temperature on reproduction and longevity of C. claratris was determined at 25, 30 and 35 and 40°C. Both inseminated and virgin females failed to reproduce at 40°C. Virgin females produced only male offspring, confirming arrhenotoky. The sex ratio of the offspring of fertilized females was strongly female-biased, except at 25°C. Mean total fecundity per female and mean daily total fecundity per female were highest for both virgin and inseminated females at 30°C. Female longevity was longest at 25°C and shortest at 40°C. Male longevity was longest at 30°C and shortest at 40°C. The net reproductive rate (R0) and intrinsic rate of natural increase (rm) was greatest at 30°C while, mean generation time (G) and the doubling time (t) were highest at 25°C. The finite rate of increase (λ) was fairly constant (1.1–1.5 days) over the three temperatures tested. The pest potential of C. claratris for tropical Asia is discussed.

Effects of photoperiod on development and demographic parameters of the predatory thrips Scolothrips longicornis fed on Tetranychus urticae

2020 ◽  
Vol 110 (5) ◽  
pp. 620-629
Author(s):  
Hajar Pakyari ◽  
Mark R. McNeill
Keyword(s):  
Tetranychus Urticae ◽  
Intrinsic Rate ◽  
Reproductive Rate ◽  
Natural Increase ◽  
Net Reproductive Rate ◽  
Control Programs ◽  
Rate Of Increase ◽  
Significant Difference ◽  
Scolothrips Longicornis ◽  
Almost All

AbstractThe effect of five photoperiods (0:24, 6:18; 12:12, 18:6, and 24:0 light:dark (L:D)) on the development, reproduction, and survival of the predatory thrips Scolothrips longicornis Priesner fed on the two-spotted spider mite, Tetranychus urticae Koch, was tested under laboratory conditions at 60% RH and 25°C. Development time of almost all immature stages in S. longicornis was the shortest under long day lengths (18:6 and 24:0 L:D). The adult duration of both sexes decreased with increasing light length from 6 to 24 h. The longevity of male and female decreased with increasing light length. Under a 12:12 L:D photoperiod, S. longicornis females had the longest oviposition period and longevity, highest net reproductive rate (R0 = 15.37), intrinsic rate of natural increase (r = 0.141), and finite rate of increase (λ = 1.151). Life table parameters showed a significant difference with various photoperiods. The consequences of the present research demonstrated that a 12:12 L:D photoperiod is the most favorable for the reproduction and development of S. longicornis fed on T. urticae, and that for mas rearing for augmentative biological control programs, would be the ideal photoperiod to maximize production.

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