Determination of thermal constant and development threshold of Bihar hairy caterpillar, Spilarctia obliqua Walker

Effect of six constant temperatures viz., 18±1, 21±1, 24±1, 27±1, 30±1 and 33±10C was studied on the egg hatchability, larval pupal development and adult survival of Spilarctia obliqua. Development rate of egg, larva and pupa gradually increased with increase in temperature, while total developmental period decreased. Mean developmental period of the pest decreased from 93.73 days at 18±10C to 31.20 at 33±10C. The lowest and the highest temperatures at which no development took place were found to be 12±10C and 39±10C, respectively. Regression equations between development rate and temperature were found to be Y= 0.0189 X -0.1998 (R2=0.88) for egg, Y=0.00122 X -0.0248 (R2=0.84) for small larva (1-3rd instar), Y=0.0058 X -0.0675 (R2=0.76) for large larva (4-6th instar), Y=0.0074 X-0.1075 (R2=0.94) for pupa and Y=0.0142 X-0.4363 (R2=0.79) for adults. Developmental threshold were determined to be 10.57, 11.27, 11.55, 15.28 and 10.92oC for egg, small larva, large larva, pupa, and adult respectively with corresponding thermal constant being 52.91, 344.82, 243.90, 142.85 and 70.42 degree days (DD). Thermal constant to complete a generation was found to be 854.90 DD. This was the first studies on this aspects, these estimated thermal thresholds and degree days could be used to predict the S. obliqua activity in the field for their effective management through pest forecasting.

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Thermal requirements and estimated number of generations of Neopamera bilobata (Say) in strawberry-producing regions of Brazil

Ciência Rural ◽

10.1590/0103-8478cr20170212 ◽

2017 ◽

Vol 48 (1) ◽

Author(s):

Taciana Melissa de Azevedo Kuhn ◽

Alci Enimar Loeck ◽

Marcos Botton

Keyword(s):

Adult Stage ◽

Thermal Constant ◽

Rio Grande Do Sul ◽

Degree Days ◽

Climate Chamber ◽

Thermal Threshold ◽

Developmental Threshold ◽

Thermal Requirements ◽

Developmental Thresholds ◽

The Mean

ABSTRACT: The thermal threshold and thermal requirements of Neopamera bilobata were determined, and the number of generations that this species may produce in the main strawberry-producing regions of Brazil was estimated. In a climate chamber (70±10% RH and 12h photophase) at 16, 19, 22, 25, 28, or 30±1°C, the development of 120 eggs was monitored until the adult stage, at each temperature. Nymphs were maintained in individual cages and fed on strawberry fruits of the cultivar Aromas. The mean duration and viability of the egg and nymph stages were calculated by estimating the lower and upper developmental thresholds and the thermal constant, and this information was used to estimate the number of generations per year in different strawberry-producing regions of Brazil. The egg-to-adult duration decreased as temperatures increased, up to 28°C (93.4, 83.2, 43.9, and 31.4 days at 19, 22, 25, and 28°C, respectively). Viability of nymphs was highest between 22 and 28°C. At 30°C, the egg-to-adult duration increased (36 days), while the viability decreased (11.11%). The lower egg-to-adult developmental threshold was 15.2°C and the thermal constant was 418.4 degree-days. Calculating the number of generations indicated that the largest number (5.1 generations yr-1) was obtained for the municipality of Jaboti, Paraná, and the smallest for Caxias do Sul, Rio Grande do Sul (1.9 generations yr-1). Our findings demonstrated that important strawberry-producing regions in Brazil are suitable for the development of N. bilobata.

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THE INFLUENCE OF CONSTANT TEMPERATURES ON THE NON-DIAPAUSE DEVELOPMENT OF HYSSOPUS THYMUS (HYMENOPTERA: EULOPHIDAE)

The Canadian Entomologist ◽

10.4039/ent104113-1 ◽

1972 ◽

Vol 104 (1) ◽

pp. 113-120 ◽

Cited By ~ 1

Author(s):

Paul D. Syme

Keyword(s):

Developmental Stages ◽

Climatic Conditions ◽

Thermal Constant ◽

Regression Equations ◽

Degree Days ◽

Different Temperatures ◽

Potential Impact ◽

Diapause Development ◽

The Relationship ◽

Fluctuating Temperatures

AbstractThe influence of constant temperatures on the non-diapause development of Hyssopus thymus was studied and the results of these studies are presented. A lower threshold for development of less than 12 °C and an upper threshold of about 32 °C were determined. Mean times for and rates of development at different temperatures are presented for all developmental stages. The egg is the stage most sensitive to temperature change. Regression equations describing the relationship between the rate of development and temperature for these stages are given and a thermal constant (K) of about 190 degree-days is calculated for total development. This constant is not applicable to naturally fluctuating temperatures. The results of these studies are discussed in relation to the potential impact of H. thymus on European pine shoot moth dynamics under different climatic conditions. It is concluded that H. thymus should be more effective in warmer seasons and at lower latitudes.

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Temperaturedependent development of parasitoids on two species of armoured scale insects

New Zealand Plant Protection ◽

10.30843/nzpp.2002.55.3933 ◽

2002 ◽

Vol 55 ◽

pp. 361-367 ◽

Cited By ~ 4

Author(s):

D.P. Logan ◽

C. Thomson

Keyword(s):

Linear Regression ◽

Cumulative Distribution ◽

Scale Insects ◽

Thermal Constant ◽

Regression Equations ◽

Developmental Threshold ◽

Development Rates ◽

Aspidiotus Nerii ◽

Armoured Scale Insects ◽

Duration Of Development

The duration of development of the parasitoid Encarsia citrina (Craw) (Hymenoptera Aphelinidae) on its hosts greedy scale Hemiberlesia rapax (Comstock) and oleander scale Aspidiotus nerii Bouché (Hemiptera Diaspididae) and of Signiphora merceti (Malenotti) (Hymenoptera Signiphoridae) on greedy scale was determined at five constant temperatures Weibull functions were fitted to the cumulative distribution of parasitoid emergence times and development rates for 5 50 and 95 emergence were calculated Development rates for each parasitoidscale combination were described by the same linear regression equations for 50 emergence and for 95 emergence Developmental threshold and thermal constant for 50 and 95 emergence of parasitoids was 103C and 3638 D and 103C and 4412 D The threshold and thermal constant for 5 emergence varied from 93C to 123C and 2254 D to 3282 D Duration of development in the field was simulated using 13 months of hourly temperatures recorded at Te Puke

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Reciprocal crosses between two populations ofTrissolcus vassilievi(Mayr) (Hymenoptera: Scelionidae) reveal maternal effects on thermal phenotypes

Bulletin of Entomological Research ◽

10.1017/s0007485315000164 ◽

2015 ◽

Vol 105 (3) ◽

pp. 355-363

Author(s):

S. Iranipour ◽

P. BenaMolaei ◽

S. Asgari ◽

J.P. Michaud

Keyword(s):

Maternal Effect ◽

Developmental Time ◽

Adult Survival ◽

Thermal Constant ◽

Temperature Threshold ◽

Degree Days ◽

Sunn Pest ◽

Female Progeny ◽

Reciprocal Crosses ◽

Two Populations

AbstractThe egg parasitoidTrissolcus vassilievi(Mayr) (Hymenoptera: Scelionidae) is a significant natural enemy of the sunn pest,Eurygaster integricepsPuton (Hemiptera: Scutelleridae), the most important pest of wheat in Iran. This study examined the developmental time and egg-to-adult survival of two geographically separate populations ofT. vassilievion two corresponding host populations at five constant temperatures ranging from 15.0 to 35.0±1°C. No wasps of either population emerged at 15.0°C and the temperature threshold for development was similar between populations, ranging from 13.1±0.3 to 13.8±0.4°C for males and 12.2±0.1 to 12.6±0.1°C for females, but the thermal constant varied with gender and parasitoid population. Development of wasps from the colder Tabriz location was slower, with thermal constants for males and females of 172.6±3.1 and 204.1±1.2 degree-days, respectively, compared to Varamin wasps with 164.7±3.0 and 195.6±1.3 degree-days, respectively. Based on genetic inheritance patterns, reciprocal crosses between the two populations were expected to result in females with thermal phenotypes intermediate to their parental populations, and males that resembled their mothers. However, female progeny of crosses more closely resembled their maternal population, indicating a maternal effect on thermal phenotype. Furthermore, the magnitude of the maternal effect on the thermal constant was asymmetric and was more strongly expressed by Varmin than Tabriz females. These results suggest the possibility of using selective crosses between wasp populations, in combination with artificial selection in the laboratory, to tune the thermal phenotype of parasitoids to specific regions prior to augmentative releases.

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GROWTH THRESHOLD AND DEGREE DAYS REQUIREMENT FOR DEVELOPMENT AND GROWTH OF CITRUS MEALYBUG Planococcus citri (Risso), HEMIPTERA : PSEUDOCOCCIDAE

IRAQI JOURNAL OF AGRICULTURAL SCIENCES ◽

10.36103/ijas.v48i2.417 ◽

2017 ◽

Vol 48 (2) ◽

Author(s):

Al-Shammari & Al-Zubaidy

Keyword(s):

Growth Rate ◽

Growth And Development ◽

Developmental Time ◽

Thermal Constant ◽

Planococcus Citri ◽

Degree Days ◽

Developmental Threshold ◽

Citrus Mealybug ◽

Mealy Bug ◽

The Impact

Laboratory studies was conducted in Biocontrol unit- Faculty of Agriculture- University of Baghdad in order to determine the impact of different temperatures 15, 20, 25, 30 and 35 ±2 C° on the development and growth rate of different stages of mealy bug P.citri. The results showed that the total developmental time from (egg - adult)of the mealy bug were 24.0, 28.08, 39.67 and 73.31 days respectively. With significant rearing differences on temperatures 15, 20, 25 and 30 ±2 C° respectively, while no development and growth rate on temperature 35±C°. the developmental threshold for the mealy bug stages eggs, crawlers, 2nd and 3rd nymphal instars as well as the duration of the egg to adult were different, being 7.1, 7.26, 7.08, 7.12 and 7.15C° respectively, while 116.27, 136.98 and 172.4 thermal units for degree days required for growth and development while the thermal constant for the period from egg to adult was 526.31. Optimum temperature was 27.85C ͦ while Upper threshold was 33.64 C° for P.citri Which refers to the lack of suitable high temperature for growth and development .

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GROWTH THRESHOLD AND DEGREE DAYS REQUIREMENT FOR DEVELOPMENT AND GROWTH OF CITRUS MEALYBUG Planococcus citri (Risso), HEMIPTERA : PSEUDOCOCCIDAE

IRAQI JOURNAL OF AGRICULTURAL SCIENCES ◽

10.36103/ijas.v48i2.415 ◽

2017 ◽

Vol 48 (2) ◽

Author(s):

Al-Shammari & Al-Zubaidy

Keyword(s):

Growth Rate ◽

Growth And Development ◽

Developmental Time ◽

Thermal Constant ◽

Planococcus Citri ◽

Degree Days ◽

Developmental Threshold ◽

Citrus Mealybug ◽

Mealy Bug ◽

The Impact

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Effect of Temperature on the Development and Survival of Feltiella Acarisuga (Vallot) (Diptera: Cecidomyiidae) Preying on Tetranychus Urticae (Koch) (Acari: Tetranychidae)

Insects ◽

10.3390/insects12060508 ◽

2021 ◽

Vol 12 (6) ◽

pp. 508

Author(s):

Yong-Seok Choi ◽

Sung-Hoon Baek ◽

Min-Jung Kim

Keyword(s):

Developmental Stages ◽

Gall Midge ◽

Mass Rearing ◽

Immature Stage ◽

Development Rate ◽

Effect Of Temperature ◽

Thermal Constant ◽

Fundamental Information ◽

Threshold Temperatures ◽

Response To Temperature

The predatory gall midge, Feltiella acarisuga (Vallot) (Diptera: Cecidomyiidae), is an acarivorous species that mainly feeds on spider mites (Acarina: Tetranychidae). Because of its cosmopolitan distribution and predation efficacy, it is considered an important natural enemy available as a biological agent for augmentative biocontrol. However, despite its practical use, the thermal development and survival response to temperature have not yet been fully studied. In this study, we investigated the stage-specific development and survival of F. acarisuga at seven temperatures (11.5, 15.7, 19.8, 23.4, 27.7, 31.9, and 35.4 °C) to examine the effect of temperature on its lifecycle. All developmental stages could develop at 11.5–31.9 °C, but the performance was different according to the temperature. From the linear development rate models, the lower development threshold and thermal constant of the total immature stage were estimated at 8.2 °C and 200 DD, respectively. The potential optimal and upper threshold temperatures for the total immature stage were estimated as 29.3 and 35.1 °C using a non-linear development model. The operative thermal ranges for development and survival at 80% of the maximum rate were 24.5–32.3 and 14.7–28.7 °C, respectively. Thus, it was suggested that 24.5–28.7 °C was suitable for the total immature stage. In contrast, conditions around 8 °C and 35 °C should be avoided due to the lower development rate and high mortality. Our findings provide fundamental information for an effective mass-rearing and releasing program of F. acarisuga in an augmentative biocontrol program and help to predict phenology.

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INFLUENCE OF PHOTOPERIOD AND WATER STRESS ON GROWTH, YIELD AND DEVELOPMENT RATE OF BARLEY MEASURED IN HEAT UNITS

Canadian Journal of Plant Science ◽

10.4141/cjps87-003 ◽

1987 ◽

Vol 67 (1) ◽

pp. 21-34 ◽

Cited By ~ 11

Author(s):

L. M. DWYER ◽

D. W. STEWART

Keyword(s):

Water Stress ◽

Leaf Area ◽

Dry Matter ◽

Growth Yield ◽

Development Rate ◽

Degree Days ◽

Heat Units ◽

Matter Production ◽

Stress Maximum ◽

Significant Yield

Barley (Hordeum vulgare ’Bruce’) was grown in a greenhouse under three photoperiods (8, 12 and 16 h) and nine watering treatments, resulting in different timing, duration and intensity of water stress. Phenological development, according to the Feekes scale, was monitored three times a week and leaf area was measured weekly from tillering to ripening. Final aboveground and root dry matter production and grain yield were obtained at harvest. Phenological observations were fit to a nonlinear photothermal model that expressed phenological development as a function of heat units modified by photoperiod. In the absence of water stress, maximum leaf area was directly proportional to photoperiod and the time of maximum leaf area was delayed at longer photoperiods. Water stress hastened leaf area senescence and, in general, the more severe the stress, the greater the reduction in leaf area. Most stress treatments also resulted in lower shoot/root ratios than found in well-watered controls, as well as significant yield reductions. Reduction in biomass and yield components appeared independent of photoperiod. In contrast, not only was phenological development rate proportional to photoperiod, but the effect of water stress on development rate was modified by photoperiod. Development was significantly delayed by several water stress treatments; no treatment significantly hastened development. A stress period from tillering to the beginning of stem extension caused the largest, and most consistent, delay and the duration of the delay was inversely proportional to the photoperiod.Key words: Barley, degree days, phenology, leaf area, biomass

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Survival and development of different life stages of three Ceratitis spp. (Diptera: Tephritidae) reared at five constant temperatures

Bulletin of Entomological Research ◽

10.1079/ber2002188 ◽

2002 ◽

Vol 92 (6) ◽

pp. 461-469 ◽

Cited By ~ 88

Author(s):

P.F. Duyck ◽

S. Quilici

Keyword(s):

Simulation Models ◽

Fruit Fly ◽

Thermal Constant ◽

Immature Stages ◽

Developmental Threshold ◽

Laboratory Rearing ◽

Larval Stages ◽

Survival And Development ◽

Lower Developmental Threshold ◽

Computer Simulation Models

AbstractFruit flies (Diptera: Tephritidae) are the most damaging pests on fruit crops on Réunion Island, near Madagascar. Survival and development of the Mediterranean fruit fly, Ceratitiscapitata (Wiedemann), the Natal fruit fly, C. rosa Karsch and the Mascarenes fruit fly, C. catoirii Guérin-Mèneville were compared at five constant temperatures spanning 15 to 35°C. Durations of the immature stages of C. capitata, C. rosa and C catoirii ranged from 14.5–63.8, 18.8–65.7 and 16.8–65.8 days, respectively, at 30–15°C. The lower developmental threshold and thermal constant were calculated using the temperature summation model. The thermal constant for total development of the immature stages of C. capitata, C. rosa and C. catoirii were 260, 405 and 356 DD, respectively. Species differed mainly during the larval stages and ovarian maturation period, with smaller differences in the egg stage. Ceratitis rosa appeared to be better adapted to low temperatures than the two other species as it showed a lower larval developmental threshold of 3.1°C compared to 10.2°C for C. capitata and 8.9°C for C. catoirii. Overall, C. catoirii had a low survival rate within the range of temperatures studied. The different responses of the three Ceratitis species to various temperatures explain to some extent their distribution on the island. The results obtained will be used for optimizing laboratory rearing procedures and for constructing computer simulation models to predict fruit fly population dynamics.

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A TEMPERATURE-DEPENDENT MODEL OF EGG DEVELOPMENT OF THE WESTERN CORN ROOTWORM, DIABROTICA VIRGIFERA VIRGIFERA LECONTE (COLEOPTERA: CHRYSOMELIDAE)

The Canadian Entomologist ◽

10.4039/ent1231183-6 ◽

1991 ◽

Vol 123 (6) ◽

pp. 1183-1197 ◽

Cited By ~ 16

Author(s):

A.W. Schaafsma ◽

G.H. Whitfield ◽

C.R. Ellis

Keyword(s):

Simulation Model ◽

Diabrotica Virgifera Virgifera ◽

Base Temperature ◽

Diabrotica Virgifera ◽

Degree Days ◽

Egg Development ◽

Egg Hatch ◽

Developmental Threshold ◽

Soil Temperatures ◽

Developmental Rates

AbstractDevelopmental rates of post-diapause eggs of Diabrotica virgifera virgifera LeConte were compared in the laboratory at six constant temperatures, 12, 16, 20, 24, 28, and 32°C. Linear and nonlinear models were fitted to temperature versus developmental data and were used to predict egg hatch in the field. A four-parameter model fitted to median developmental rates (r2 = 0.99) indicated that development was linear between 16 and 28°C, optimal at 28°C, and decreased at 32°C. The lower development threshold (± SE) (10.5 ± 0.1°C) was determined by linear regression and the x-intercept method. Completion of post-diapause egg development required 258 ± 3 degree-days (± SE) above the base temperature. This compared well with the mean degree-days accumulated to 50% hatch (± SE) of 265 ± 24 which we observed in the field at several locations over 3 years using a degree-day model incorporating an 11°C developmental threshold and soil temperatures at 5- and 10-cm depths. A stochastic simulation model, incorporating a nonlinear developmental function dependant on soil temperatures taken every 2 h also predicted 50% hatch within 2 days. This model was validated in the field with 19 independent records of soil temperatures for several locations at two depths in the soil over 3 years. The simulation model accurately predicted time of 5 and 95% hatch, which indicates that this model has broad application in predicting the pattern of egg hatch for pest management.

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