The effect of Bombylius pulchellus (Diptera; Bombyliidae) and other mortality factors upon the biology of Halictus ligatus (Hymenoptera; Halictidae) in southern Ontario

1988 ◽  
Vol 66 (3) ◽  
pp. 611-616 ◽  
Author(s):  
Laurence Packer
Keyword(s):  
Survival Rate ◽  
Fungal Infection ◽  
Brood Cell ◽  
Immature Stages ◽  
Microbial Infection ◽  
Mortality Factors ◽  
Southern Ontario ◽  
Two Factors ◽  
Halictus Ligatus ◽  
Reproductive Brood

Two factors were important in causing brood mortality in a southern Ontario population of Halictus ligatus: parasitism by larvae of the bombyliid Bombylius pulchellus and various forms of microbial infection of bee immatures or their pollen ball food. Bombyliid larvae consumed host prepupae or, less commonly, young pupae, restricted their attack mostly to the reproductive brood, and were contagiously distributed within the nest population. All immature stages were susceptible to fungal infection or disease but such pathogens did not seem to spread among cells within nests, indicating that bees may be able to prevent the spread of disease from one brood cell to another. Filling affected cells with earth may accomplish this brood hygiene. The survival rate of worker and reproductive brood immatures approximated 90%. Reproductive brood mortality affected females more than males. Reproductive brood mortality was probably underestimated: filled-in cells that may represent brood mortality were not included in these estimates.

Major Factors in Survival of the Immature Stages of Pieris rapae (L.)

1966 ◽  
Vol 98 (6) ◽  
pp. 653-662 ◽  
Author(s):  
D. G. Harcourt
Keyword(s):  
Population Dynamics ◽  
Survival Rate ◽  
Pieris Rapae ◽  
Pupal Stage ◽  
Population Data ◽  
Life Tables ◽  
Immature Stages ◽  
Mortality Factors ◽  
Key Factor ◽  
Major Factors

AbstractDetailed studies on the population dynamics of the imported cabbageworm, Pieris rapae (L.), have been carried out at Merivale, Ontario, since 1959. A method for preparing life tables is described and a mean life table is presented for 18 generations of the species on cabbage. Population data for the preadult period show that there are three age intervals during which extensive mortality may occur: (1) between hatching and the second moult, (2) instars three to five, and (3) during the pupal stage. The analysis of successive age-interval survivals in relation to generation survival showed that the latter is largely determined by the survival rate for (2). Examination of the life tables revealed that a granulosis of the larvae caused by a capsule virus is the key factor in generation survival. Major mortality factors include rainfall and parasites.

The social organisation of Halictus ligatus (Hymenoptera; Halictidae) in southern Ontario

1986 ◽  
Vol 64 (10) ◽  
pp. 2317-2324 ◽  
Author(s):  
Laurence Packer
Keyword(s):  
Ovarian Development ◽  
Social Organisation ◽  
Southern Ontario ◽  
Activity Phase ◽  
The Social ◽  
Halictus Ligatus ◽  
Small Colony ◽  
Worker Brood ◽  
The One ◽  
Reproductive Brood

The social organisation of Halictus ligatus was studied at Victoria, southern Ontario. At this locality, the one worker brood has a protracted period of emergence; this results in small colony populations throughout the summer activity phase. Workers average 12.7% smaller than their queens, 60% of them have some ovarian development, and 42% of them mate. More males are produced towards the very end of the first brood than earlier in the spring provisioning phase. These late first brood males probably survive to mate with reproductive brood females. In orphaned nests, one worker dominates the others to become a replacement queen. Most replacement queens are mated and orphaned colonies produce reproductives of both sexes. Data from this population are compared with those of other studies of this, and other, halictine species.

Multiple-foundress associations in a temperate population of Halictus ligatus (Hymenoptera; Halictidae)

1986 ◽  
Vol 64 (10) ◽  
pp. 2325-2332 ◽  
Author(s):  
Laurence Packer
Keyword(s):  
Reproductive Potential ◽  
Sweat Bee ◽  
Reproductive Competition ◽  
Southern Ontario ◽  
Parental Manipulation ◽  
Single Foundress ◽  
Halictus Ligatus ◽  
Reproductive Brood ◽  
Polistine Wasps ◽  
Previous Summer

Thirteen pleometrotic (multiple-foundress) nests of the primitively social sweat bee Halictus ligatus were excavated in the summer of 1984 at Victoria, near Toronto, southern Ontario. Subordinate foundresses were significantly smaller than both dominant females in pleometrotic nests and females that nested solitarily. Most subordinates were smaller than the workers that they helped to raise. These small females could have been surviving workers from the previous summer or the offspring of workers. It seems unlikely that they were malnourished reproductive brood individuals produced as a result of parental manipulation. In successful nests, the number of workers produced was positively correlated with the number of founding females such that productivity per foundress remained fairly constant. Pleometrotic nests also produced more reproductives than haplometrotic (single-foundress) ones. Subordinates may occasionally lay reproductive brood eggs. The increased productivity of multiple-foundress nests was not quite sufficient, by itself, to select for subordinate behaviour. The small subordinates had lower potential productivities in comparison to the larger females. This decreased reproductive potential, when combined with the increased productivity of pleometrotic nests, was sufficient to make subordinate behaviour selectively advantageous. When both factors are taken together, subordinate behaviour is selected for as long as the coefficient of relatedness between dominant and subordinate individuals is greater than 1/4. This indicates that high coefficients of relatedness are not necessary for pleometrosis to be selectively advantageous under the conditions found in this study. Dominant females may suffer increased reproductive competition from their numerous workers. This, plus the difficulty of ensuring association with siblings in spring, may be the reason why multiple-foundress associations were uncommon at this locality. The data presented here are compared with those from other studies of this species. The factors promoting pleometrosis in halictines are compared with those that result in multiple-foundress associations in temperate polistine wasps.

INFLUENCE OF TEMPERATURE AND HUMIDITY ON MORTALITY AND RATE OF DEVELOPMENT OF IMMATURE STAGES OF THE MITE TYROPHAGUS PUTRESCENTIAE (SCHRANK) (ACARINA: ACARIDAE) REARED ON MOLD CULTURES

1961 ◽  
Vol 39 (4) ◽  
pp. 419-426 ◽  
Author(s):  
I. Rivard
Keyword(s):  
Sex Ratio ◽  
Indirect Effect ◽  
Food Products ◽  
Immature Stages ◽  
Direct Influence ◽  
Tyrophagus Putrescentiae ◽  
Rate Of Development ◽  
Influence Of Temperature ◽  
Temperature And Humidity ◽  
Two Factors

Tyrophagus putrescentiae (Schrank), a mite that infests stored food products, was reared individually on mold cultures at all combinations of five temperatures and four humidities. Mortality during immature stages was lowest at 72.5° F and 80% to 90% R.H. Development was usually accelerated by an increase in either of these two factors. Temperature and humidity had a direct influence on mortality and rate of development, but humidity also had an indirect effect by affecting the mold on which the mite feeds. Adults obtained at 70% R.H. were usually relatively small in size. Sex ratio of the adults was approximately one to one; the males developed faster than the females.

scholarly journals The Used of Natural Anesthetic Materials Nutmeg Seed Oil in the Transportation of Sumatran Fish Fingerlings (Puntius tetrazona)

2021 ◽  
pp. 1-10
Author(s):  
Walim Lili ◽  
Muhamad Fikri Wahyudin ◽  
Asep Agus Handaka Suryana ◽  
Kiki Haetami
Keyword(s):  
Survival Rate ◽  
Induction Time ◽  
Recovery Time ◽  
Seed Oil ◽  
Fish Mortality ◽  
Metabolic Disturbances ◽  
Two Factors ◽  
Test Fish ◽  
Four Levels ◽  
And Control

The low survival rate in Sumatran fish fingerlings transportation is a problem related to metabolic disturbances that cause death. The addition of nutmeg seed oil in the transportation medium is expected to reduce the rate of respiration and metabolism, so that fish mortality can be minimized. The purpose of this study was to determine the effective concentration of nutmeg seed oil to maintain the highest survival rate of Sumatran fish fry transported during treatment and to analyze its effect on induction time and recovery time. This research was carried out from January to March 2021 in the Ciparanje wet laboratory, Faculty of Fisheries and Marine Sciences, Padjadjaran University. This research was conducted experimentally using a factorial randomized group design (FRGD) consisting of two factors, namely the concentration of four levels (0.03, 0.06, 0.09 ml/L and control) and duration of three levels (3, 5, and 7 hours) which was repeated three times. This research uses a closed transportation system. Parameters observed were induction time and conscious recovery time of test fish, post-transportation and post-maintenance survival for 7 days and water quality consisting of temperature, DO, pH, and ammonia. The results showed that the effective nutmeg seed oil for the anesthesia of Sumatran fish fry transported was 0.03 ml/L with a transportation duration of 3 hours because it had an induction time of 08:07, recovery time of 02:41 and postoperative survival rate. transportation by 98.33% and post-maintenance for 7 days by 91.49%. Temperature parameters are 22.7oC, DO is ±10.3 mg/L, pH is ± 6.83 and ammonia is ±0.0010 mg/L.

Ozone as a Potential Fumigant Alternative for the Management of Sitophilus oryzae (Coleoptera: Curculionidae) in Wheat

2019 ◽  
Vol 112 (4) ◽  
pp. 1953-1963 ◽  
Author(s):  
Barbara A Amoah ◽  
Rizana M Mahroof
Keyword(s):  
Survival Rate ◽  
Exposure Time ◽  
Insect Pest ◽  
Sitophilus Oryzae ◽  
Adult Emergence ◽  
Rice Weevil ◽  
Ozone Exposure ◽  
Immature Stages ◽  
Gas Loss ◽  
Wheat Kernels

Abstract Gaseous ozone, an oxidizing agent used as a disinfectant in food processing and preservation, has potential for the control of stored product insects. In this study, we investigated ozone for the management of the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), a serious stored product insect pest. We exposed eggs, immature stages within wheat kernels, and adults of the rice weevil to 200-ppm ozone for 12, 24, 36, 48, and 60 h. Insects were placed at 5, 15, or 25 cm depth within a wheat mass in PVC pipes (10 cm in diameter, 30 cm in height) and exposed to ozone. Egg eclosion was recorded 10 d after treatment (DAT), and immature stages were observed for adult emergence 28 DAT. Adults were observed for survival immediately after ozone exposure and again at 1 and 2 DAT. Egg eclosion was significantly lower at 5 cm compared with 25 cm at all exposure times, but not the 12-h exposure time. For each exposure time tested, significantly lesser adults developed from kernels and none of the adults survived at the 5 cm depth compared with the 15 and 25 cm depths. Survival rate of adults was significantly higher at 25 cm depth than at 15 cm depth at the 24–60 h. The deeper the insect in the grain mass, the higher the survival rate. The work reported suggests that ozone is effective in killing all life stages of S. oryzae; however, the efficacy of the gas is dependent on the concentration, exposure time, depth, and gas loss.

The Biology and Behaviour of the European Pine Shoot Moth Rhyacionia buoliana (Schiff.), in Southern Ontario II. Egg, Larva, and Pupa

1963 ◽  
Vol 95 (8) ◽  
pp. 844-863 ◽  
Author(s):  
P. J. Pointing
Keyword(s):  
Small Groups ◽  
Ground Surface ◽  
Late Summer ◽  
Feeding Period ◽  
Tree Crown ◽  
Mortality Factors ◽  
Short Supply ◽  
Southern Ontario ◽  
Web Construction ◽  
Third Instar Larvae

AbstractThis is the second of two papers on this subject. The eggs of R. buoliana are usually found singly or in small groups on the hark or needle sheaths of new shoots, except under conditions of severe infestation where new foliage is in short supply. The first two instars feed on needles from within webs. Third-instar larvae mine one or more buds and cease feeding in late summer before the advent of unfavourable temperatures. Low temperature, lethal to overwintering third-instar larvae, is one of the most important and readily measured mortality factors, Larvae spin webs and moult before they resume feeding in April or May. Migration, usually upward in the tree crown, and web construction continue throughout the spring feeding period. Larvae within two feet of the ground surface on trees less than eight feet tall complete their development earlier than larvae at higher levels. Parasitism, based on previous extensive surveys, has very likely been underestimated.

scholarly journals [NO TITLE AVAILABLE]

1998 ◽  
Vol 40 (3) ◽  
pp. 173-176 ◽  
Author(s):  
Noraida ZERPA ◽  
Jorge MORENO ◽  
Julio GONZALEZ R. ◽  
Oscar NOYA
Keyword(s):  
Growth Rate ◽  
Survival Rate ◽  
Central America ◽  
Generation Time ◽  
Immature Stages ◽  
Intrinsic Growth Rate ◽  
Anopheles Albimanus ◽  
The Caribbean ◽  
Latin America Countries ◽  
Successful Colonization

Anopheles albimanus is one of the main vectors of malaria in Central America and the Caribbean, based on its importance, there are previous reports of the successful colonization of this species in Latin America countries. Mosquitoes were collected in the Aragua State of Venezuela colonized in the laboratory, using a simple and efficient maintenance method. Based on life table calculations under well established laboratory conditions, the Survival Rate Probability was constant and always close to 1 in immature stages, the Reproductive Net Rate (Ro) was 3.83, the generation time (Tc) was 24.5 days and the Intrinsic Growth Rate (rm) was 0.0558. This is the first report of the colonization of A. albimanus in Venezuela.

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