scholarly journals Developing apple leafcurling midge rearing techniques

2018 ◽  
Vol 71 ◽  
pp. 353
Author(s):  
Amanda J. Hawthorne ◽  
Dominic E. Hartnett
Keyword(s):  
Mass Rearing ◽  
Day Length ◽  
Controlled Environment ◽  
Ambient Conditions ◽  
Export Markets ◽  
Long Day ◽  
Large Numbers ◽  
Oviposition Substrate ◽  
Rearing Techniques ◽  
Dasineura Mali

Apple leafcurling midge (Dasineura mali; ALCM) is considered a quarantine pest in some of New Zealand’s valuable export markets. Research into alternatives to methyl bromide as a fumigant requires a mass rearing programme to provide large numbers of all life stages. Our aim was to focus on developing an understanding of the environmental conditions that break ALCM diapause and facilitate ALCM oviposition. A trial was conducted comparing ALCM oviposition rates on apple seedlings in a controlled temperature room versus a shade house in ambient conditions over the summer months. Additionally, long day length and high humidity conditions were tested to break the diapause of ALCM cocooning larvae. Oviposition rates on young apple seedlings were similar in the controlled environment room and the shade house; however, apple seedlings grew better in the shade house due to lower incidence of powdery mildew. Adults emerged from ALCM cocoons that had been in diapause for five months and then held at 20.9°C for seven days. Conditions to break ALCM diapause have been determined. Seedlings at the six- to eight-leaf stage have the potential to provide an oviposition substrate. Further investigations are required into artificial oviposition substrates and the development of a larval diet to mass rear ALCM larvae.

scholarly journals Cold storage and gamma irradiation of Sitotroga cerealella Olivier eggs (Lepidoptera: Gelechiidae) in relation to the success of parasitism by Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae)

2019 ◽  
Vol 29 (1) ◽  
Author(s):  
Naglaa F. Abdel-Hameid ◽  
I. R. M. Elzoghby ◽  
A. L. Mehany ◽  
W. A. A. Sayed
Keyword(s):  
Gamma Irradiation ◽  
Cold Storage ◽  
Mass Rearing ◽  
Egg Parasitoid ◽  
Sitotroga Cerealella ◽  
Trichogramma Evanescens ◽  
Control Programs ◽  
Angoumois Grain Moth ◽  
Rearing Techniques ◽  
The Times

AbstractThe performance of parasitism by the egg parasitoid, Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae) on eggs of Angoumois grain moth, Sitotroga cerealella Olivier (Lepidoptera: Gelechiidae) was investigated under cold storage and gamma irradiation treatments of the host eggs. Cold storage treatment could improve the parasitoid mass rearing techniques and reduced the costs of biological control programs, while gamma irradiation might be used as a supplementary support at the times of high demand. The suitability of the S. cerealella eggs, stored at – 20 °C for 0.5, 1, or 2 h. as a host for T. evanescens was evaluated. The sensitivity of S. cerealella eggs to gamma irradiation treatments and the acceptability of irradiated eggs for parasitism by T. evanescens females for the parental P and F1 generations were examined. The results revealed that parasitism was drastically reduced more than adult’s emergence and sex-ratio (% of females) after cold storage periods of S. cerealella eggs. Moreover, the parasitism percentages were relatively reduced to (97.1, 96.1, 93.03, and 92.7 %) after irradiating the S. cerealella eggs at 40, 60, 80, and 100 Gy, respectively than the control (97.3% emergence). The percentages of emergence and females’ percent were slightly decreased by gamma irradiation doses, while, equal preferred by the F1 generation of parasitoid that produced from irradiated S. cerealella eggs.

scholarly journals Day Length and Weather Effects on Children’s Physical Activity and Participation in Play, Sports, and Active Travel

2012 ◽  
Vol 9 (8) ◽  
pp. 1105-1116 ◽  
Author(s):  
Anna Goodman ◽  
James Paskins ◽  
Roger Mackett
Keyword(s):  
Physical Activity ◽  
Cloud Cover ◽  
Objective Measure ◽  
Active Travel ◽  
Day Length ◽  
Physically Active ◽  
The Public ◽  
Daylight Saving ◽  
Long Day ◽  
Children’S Physical Activity

Background:Children in primary school are more physically active in the spring/summer. Little is known about the relative contributions of day length and weather, however, or about the underlying behavioral mediators.Methods:325 British children aged 8 to 11 wore accelerometers as an objective measure of physical activity, measured in terms of mean activity counts. Children simultaneously completed diaries in which we identified episodes of out-of-home play, structured sports, and active travel. Our main exposure measures were day length, temperature, rainfall, cloud cover, and wind speed.Results:Overall physical activity was higher on long days (≥ 14 hours daylight), but there was no difference between short (< 9.5 hours) and medium days (10.2–12.6 hours). The effect of long day length was largest between 5 PM and 8 PM, and persisted after adjusting for rainfall, cloud cover, and wind. Up to half this effect was explained by a greater duration and intensity of out-of-home play on long days; structured sports and active travel were less affected by day length.Conclusions:At least above a certain threshold, longer afternoon/evening daylight may have a causal role in increasing child physical activity. This strengthens the public health arguments for daylight saving measures such as those recently under consideration in Britain.

scholarly journals Prior exposure to long-day photoperiods alters immune responses and increases susceptibility to parasitic infection in stickleback

2020 ◽  
Vol 287 (1930) ◽  
pp. 20201017
Author(s):  
James R. Whiting ◽  
Muayad A. Mahmud ◽  
Janette E. Bradley ◽  
Andrew D. C. MacColl
Keyword(s):  
Immune Responses ◽  
Parasitic Infection ◽  
Population Variation ◽  
Host Susceptibility ◽  
Day Length ◽  
Previous Exposure ◽  
Parasite Abundance ◽  
Susceptibility To Infection ◽  
Long Day ◽  
Host Parasite

Seasonal disease and parasitic infection are common across organisms, including humans, and there is increasing evidence for intrinsic seasonal variation in immune systems. Changes are orchestrated through organisms' physiological clocks using cues such as day length. Ample research in diverse taxa has demonstrated multiple immune responses are modulated by photoperiod, but to date, there have been few experimental demonstrations that photoperiod cues alter susceptibility to infection. We investigated the interactions among photoperiod history, immunity and susceptibility in laboratory-bred three-spined stickleback (a long-day breeding fish) and its external, directly reproducing monogenean parasite Gyrodactylus gasterostei . We demonstrate that previous exposure to long-day photoperiods (PLD) increases susceptibility to infection relative to previous exposure to short days (PSD), and modifies the response to infection for the mucin gene muc2 and Treg cytokine foxp3a in skin tissues in an intermediate 12 L : 12 D photoperiod experimental trial. Expression of skin muc2 is reduced in PLD fish, and negatively associated with parasite abundance. We also observe inflammatory gene expression variation associated with natural inter-population variation in resistance, but find that photoperiod modulation of susceptibility is consistent across host populations. Thus, photoperiod modulation of the response to infection is important for host susceptibility, highlighting new mechanisms affecting seasonality of host–parasite interactions.

Environmental influences on light and dark CO2 fixation by Kalanchoe daigremontiana

1975 ◽  
Vol 53 (11) ◽  
pp. 1132-1138 ◽  
Author(s):  
E. Nalborczyk ◽  
L. J. Lacroix ◽  
R. D. Hill
Keyword(s):  
Co2 Fixation ◽  
Red Light ◽  
Day Length ◽  
Low Oxygen ◽  
Long Day ◽  
C Value ◽  
Warm Night ◽  
Dark Co2 Fixation ◽  
Kalanchoë Daigremontiana ◽  
Kalanchoe Daigremontiana

The influence of day length, light quality, temperature, drought, and oxygen concentration on gas exchange of Kalanchoe daigremontiana was investigated. The ratio of photosynthesis to dark CO2 fixation with plants under a long-day and short-warm-night regime was 2.0 and under a short-day and long-cool-night regime, 0.2. With drought conditions this value may be less than 0.02. Under low oxygen concentrations high photosynthetic rates of about 20 mg CO2 dm−2 h−1 were observed with a compensation point of about 20 ppm. Restricting CO2 supply to dark periods produced plants with a δ13C value of −10.6‰. Restricting CO2 supply to light periods gave a δ13C value of −25.9‰, whereas no control of CO2 gave δ13C values of −15‰. The data obtained suggest that variations in δ13C values in Kalanchoe result from changes in the proportion of light and dark CO2 fixation.Far-red light and oxygen promoted the release of CO2 from Kalanchoe after the plants had undergone a period of dark CO2 fixation. Maximum release occurred within about 1 h. The effect could be reversed by removal of either far-red light or oxygen. Decreases in the acidity of the plants accompanied CO2 release, which indicated that decarboxylation of a C4 acid was the source of the CO2.

Effects of photoperiod and temperature on flowering of twelve Stylosanthes species

1977 ◽  
Vol 17 (86) ◽  
pp. 417 ◽  
Author(s):  
DF Cameron ◽  
L't Mannetje ◽  
Mannetje L 't
Keyword(s):  
High Temperatures ◽  
Reproductive Strategies ◽  
Photoperiod Response ◽  
Controlled Environment ◽  
Climatic Adaptation ◽  
Short Day ◽  
Long Day ◽  
Controlled Environments ◽  
Delayed Flowering ◽  
Strong Control

The flowering of accessions from 12 Stylosanthes species was studied in two controlled environment experiments and a glasshouse experiment. In controlled environments photoperiod exerted a strong control over flowering with short day, day neutral and long day responses being recognized. High temperatures generally delayed flowering, increased the node of first flower and reduced the number of inflorescences, but acted as a modifier only of the basic control exerted by photoperiod. With natural photoperiods in the glasshouse, flowering responses were generally consistent with the photoperiod responses observed in controlled environments. The climatic adaptation of Stylosanthes species is discussed in relation to the alternative reproductive strategies of the photoperiod response types.

Hypoglycemia and torpor in Siberian hamsters

1999 ◽  
Vol 276 (3) ◽  
pp. R776-R781 ◽  
Author(s):  
John Dark ◽  
Daniel A. Lewis ◽  
Irving Zucker
Keyword(s):  
Blood Glucose ◽  
Body Temperature ◽  
Body Mass ◽  
Air Temperature ◽  
Day Length ◽  
Siberian Hamsters ◽  
Long Day ◽  
Necessary And Sufficient ◽  
Blood Glucose Concentrations ◽  
Torpor Bouts

We tested whether reduced blood glucose concentrations are necessary and sufficient for initiation of torpor in Siberian hamsters. During spontaneous torpor bouts, body temperature (Tb) decreases from the euthermic value of 37 to <31°C. Among hamsters that displayed torpor during maintenance in a short-day length (10 h light/day) at an air temperature of 15°C, blood glucose concentrations decreased significantly by 28% as Tb fell from 37 to <31°C and increased during rewarming so that by the time Tb first was >36°C, glucose concentrations had returned to the value preceding torpor. Hamsters did not display torpor when maintained in a long-day length (16 h light/day) and injected with a range of insulin doses (1–50 U/kg body mass), some of which resulted in sustained, pronounced hypoglycemia. We conclude that changes in blood glucose concentrations may be a consequence rather than a cause of the torpid state and question whether induction of torpor by 2-deoxy-d-glucose is due to its general glucoprivic actions.

Variability in photoperiod and the inhibition of flowering in a high latitude population of Saxifraga rivularis

1981 ◽  
Vol 59 (3) ◽  
pp. 388-391 ◽  
Author(s):  
J. A. Teeri ◽  
S. J. Tonsor
Keyword(s):  
High Latitude ◽  
High Intensity ◽  
Dark Period ◽  
Controlled Environment ◽  
Photoperiodic Control ◽  
Incandescent Light ◽  
Devon Island ◽  
Low Intensity ◽  
Long Day ◽  
Long Day Plants

A population of Saxifraga rivularis L. collected at Truelove Lowland, Devon Island, N.W.T., Canada (75°41′ N) exhibits a photoperiodic control of flowering in controlled environment chambers. The plants respond in a manner typical of long-day plants with flowering inhibited by either a 6-h daily dark period, or by a 6-h daily low intensity irradiance regime of incandescent light. The inhibition of flowering by 6 h day−1 of incandescent light does not occur if the incandescent light is given in twelve 0.5-h doses, each followed by 1 h of red-rich high intensity irradiance.

Field trials of Trichomalopsis sarcophagae (Hymenoptera: Pteromalidae) in cattle feedlots: a potential biocontrol agent of filth flies (Diptera: Muscidae)

2003 ◽  
Vol 135 (4) ◽  
pp. 599-608 ◽  
Author(s):  
K.D. Floate
Keyword(s):  
Biocontrol Agent ◽  
Natural Populations ◽  
Fold Increase ◽  
Mass Rearing ◽  
Field Trials ◽  
House Fly ◽  
Stable Fly ◽  
Large Numbers ◽  
Potential Biocontrol Agent ◽  
Paired Control

AbstractA field study was performed in southern Alberta, Canada, to assess the native wasp, Trichomalopsis sarcophagae (Gahan), as a potential biocontrol agent for house fly, Musca domestica L., and stable fly, Stomoxys calcitrans (L.). The wasp was readily reared in large numbers, which allowed for the cumulative release of an estimated 4.63 million wasps into three commercial feedlots during the 2-year study. Each of several releases predictably and repeatedly enhanced parasitism of sentinel house fly pupae, whereas parasitism remained low in three paired control feedlots where wasps were not released. Releases every 2nd week had a disproportionately greater effect than releases every 2nd month. In 1998, 1.2 million wasps were released into treatment feedlots resulting in the recovery of 3 952 T. sarcophagae from 31 500 sentinel pupae (0.13 wasps/pupa). In 1999, 3.43 million wasps were released into treatment feedlots, with the recovery of 37 763 wasps from 47 720 sentinel pupae (0.79 wasps/pupa). Hence, a 2.8-fold increase in the number of wasps released in 1999 resulted in a 6.1-fold increase in the recovery of wasps. This result supports industry recommendations of regular, repeated releases of wasps every 2nd or 4th week versus one or infrequent releases throughout the summer. There was no evidence that releases augmented overwintering populations of the wasp in subsequent years. These results provide proof-of-concept for the mass-rearing and release of T. sarcophagae as an inundative biocontrol agent for the control of pest flies in cattle confinements. Further studies will be required to assess the effect of T. sarcophagae releases on natural populations of pest flies.

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