SAMPLING LEAVES TO ESTIMATE THE DENSITY OF BROWN MITE, BRYOBIA RUBRIOCULUS (ACARINA: TETRANYCHIDAE), ON APPLES

1983 ◽  
Vol 115 (9) ◽  
pp. 1229-1231 ◽  
Author(s):  
H. J. Herbert ◽  
D. Hamilton ◽  
G. Gabor
Keyword(s):  
First Generation ◽  
Total Population ◽  
Immature Stages

AbstractIn the first generation brown mite, Bryobia rubrioculus (Scheuten), on apple inhabits the wood as well as the leaves. To eliminate sampling the wood, which is very tedious and time consuming, equations were developed to describe the total population of immature stages and adults from observations of the number of mites on the leaves alone.

scholarly journals A solitary mud-daubing wasp, Brachymenes dyscherus (Hymenoptera: Vespidae) fron Brazil with evidence of a life-cyde polyphenism

2015 ◽  
pp. 949-958
Author(s):  
Evandro Camillo
Keyword(s):  
Life Cycle ◽  
Sex Ratio ◽  
Life Table ◽  
Total Population ◽  
Total Duration ◽  
Sao Paulo ◽  
Developmental Period ◽  
Immature Stages ◽  
São Paulo ◽  
Interior Walls

Nests ( n=60 ) of a solitary mud-daubing wasp, Brachymenes dyscherus were conected at Fazenda Santa Carlota, Cajuru, Sao Paulo, Brazil ín 1995 and 1996 . The multi-celled mud nests were constructed on the interior walls of abandoned houses in dry and shaded places. Nests were composed of 1 to 4 layers with cens constructed in two paralle! series. The number of cens per nest ranged from 3 to 62. Cells containing prey (larvae of Lepidoptera) numbered fram 4 to 29. B. dyscherus is a uniyoltíne species. Adults emerge from September to December, and nesting talces place at the beginning of the following year; however, the developmental period for some immatures with proloFlged diapause l3.Sted up to 596 days. The total duration of immature stages n nests collected in 1996 was less for males than for females. The sex ratio for the total populatíon was 1 . 5 males: 1 female with males emerging earher than females. A life table was constructed, and details of lhe life cycle of the wasps and parasitoids are presented. The mos! common mOl1ality factors were either endogenous or due 10 Melittobia sp. (Eulophidae) .

scholarly journals Phenology of Population of Immature Stages of Pear Psylla, Cαcopsyllα pyri, in the Region of Magnesia (Greece)

2017 ◽  
Vol 10 ◽  
pp. 11 ◽  
Author(s):  
E. T. Stratopoulou ◽  
E.T. Capatos
Keyword(s):  
Population Density ◽  
Overlapping Generations ◽  
First Generation ◽  
Immature Stages ◽  
Basic Pattern ◽  
Environmental Pressure ◽  
Cacopsylla Pyri ◽  
Pear Psylla ◽  
Low Levels

The phenology of the population of immature stages of pear psylla, Cacopsylla pyri (L.), was studied in Greece (region of Magnesia), during the period 1988-1991 and it was found to follow a basic pattern. Pear psylla produces 5-6 gencrations per year. The first generation develops during the period February-middle April and it is quite discrets. Three overlapping generations are developed during the period front middle April until middle August but the amount of overlapping varies front year to year. Front middle August until the end of the season pear psylla produces 1-2 generations, i.e. only a part of the firth generation complotes the sixth one. Population density is generally low during the first generation but during May-June reaches verty high levels. During sommer, strong environmental pressure, supresses the population of pear psylla to low levels but it recovers again during September-October.

Mortality of the European Red Mite (Acarina: Tetranychidae) from Secretion of Peach Leaf Nectaries

1958 ◽  
Vol 90 (12) ◽  
pp. 720-721 ◽  
Author(s):  
Wm. L. Putman
Keyword(s):  
First Generation ◽  
Immature Stages ◽  
Similar Extent ◽  
European Red Mite

Every spring since it was first noticed in 1947, the first-generation immature stages of the European red mite, Metatetranychus ulmi (Koch), has suffered some mortality in peach orchards of the Niagara Peninsula of Ontario. Sometimes this mortality was negligible but in the cold, wet spring of 1949 it reached 80 per cent in some orchards. Mortality of similar extent has not been noticed on other hosts of the mite at this season; counts of a thousand or more living and dead mites on young shoots of each host at Vineland Station on May 16, 1957, showed apparent mortalities of 53 per cent on Elberta peach, 7 per cent on Italian prune, and 8 per cent on Melba apple. The mortality on peach leaves is difficult to determine, for if the mites are examined too early, many of those killed in the quiescent, premoulting condition cannot be distinguished from living ones, and if they are examined too late, the survivors may have suffered mortality from other causes.

Description of immature stages and redescription of adults of Ixodes luciae Sénevet (Acari: Ixodidae)

Zootaxa ◽  
2010 ◽  
Vol 2495 (1) ◽  
pp. 53 ◽  
Author(s):  
VALERIA C. ONOFRIO ◽  
MARCELO B. LABRUNA ◽  
JOÃO LUIZ H. FACCINI ◽  
DARCI M. BARROS-BATTESTI
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
First Generation ◽  
Neotropical Region ◽  
The Other ◽  
Immature Stages ◽  
Haller's Organ ◽  
Northern Brazil ◽  
Males And Females ◽  
Scanning Electron

The tick Ixodes luciae occurs in many countries within the Neotropical region but only adult ticks have been morphologically described. Larvae and nymphs parasitize marsupials and rodents while adults are common on marsupials. A colony of I. luciae was obtained from females collected on marsupials from the State of Rondônia, Northern Brazil. After being fed on rabbits, the specimens were maintained under controlled conditions of temperature and humidity. Unfed larvae, nymphs, males and females of the first generation were cleaned and prepared for both optical and scanning electron microscopy. Ixodes luciae is closely related to Ixodes loricatus, Ixodes schulzei, and Ixodes amarali, although each species has its own array of distinctive characters. The larva of I. luciae differs from those of both I. schulzei and I. amarali in the length of the capitulum and from I. schulzei in the number of posthalleral setae in the Haller’s organ. Nymphs differ from I. amarali, I. loricatus and I. schulzei by the length of the external spur on coxae I, and from I. schulzei and I. amarali in having slender and shorter capitulum and hypostome. Males and females of I. luciae differ from the other three species by the length of the external spur on coxae I and by the scutal punctations, which are much longer and larger, respectively, in I. luciae. However, except for a few features, the chaetotaxy is the same for larvae of the four species, not only on the idiosoma (e.g. scutum with four pairs of setae), palpi and tarsus I, but also the number of porose setae within the capsule of Haller’s organ and the prehalleral setae.

scholarly journals Morphology of the immature stages of Panorpa qinlingensis (Mecoptera: Panorpidae) with notes on its biology

2019 ◽  
Vol 20 (3) ◽  
pp. 215-224 ◽  
Author(s):  
Li-jun Cai ◽  
Bao-zhen Hua
Keyword(s):  
First Generation ◽  
Instar Larva ◽  
Central China ◽  
Compound Eyes ◽  
Immature Stages ◽  
Prepupal Stage ◽  
First Instar

The scorpionfly Panorpa qinlingensis Chou & Ran is described and illustrated in detail for its immature stages, including egg, larva, and pupa. The egg is oval with chorion decorated with irregular polygonal network. The larva is eruciform and peripneustic, bearing eight pairs of abdominal prolegs. A pair of prominent compound eyes are present on head. The first instar larva differs from later instars in possessing a prominent egg burster on frons and with clavate setae. The pupa is exarate and decticous, taking the shape of the adults. The scorpionfly is bivoltine, overwintering as prepupal stage in the soil. The durations of the egg, larval, and pupal stages are 5–9 d, 19–27 d, and 8–18 d respectively for the first generation. Adults emerge from mid May to early June and from late July to mid August in the Micang Mountain, central China.

The biology of Anopheles claviger (Mg.) (Dipt., Culicidae) in southern England

1973 ◽  
Vol 63 (2) ◽  
pp. 347-359 ◽  
Author(s):  
M. W. Service
Keyword(s):  
Larval Development ◽  
Age Structure ◽  
First Generation ◽  
Natural Populations ◽  
Blood Feeding ◽  
Physiological Age ◽  
Immature Stages ◽  
Blood Digestion ◽  
Southern England ◽  
Suction Traps

AbstractThe biology of Anopheles claviger (Mg.) was studied for a varying number of years in three localities in southern England. The fluctuations in the proportions of the larval instars and pupae were studied by weekly sampling throughout the year. The population overwintered from October to April as pre-adults, and in mid-winter larval development was arrested, but was resumed in March. The construction of a simple life-table showed the existence of a large mortality of immature stages during the overwintering period. Females were sampled at two localities by human bait catches, and at one also by insect suction traps. There was an interval of 1–2 weeks between adult emergences in April and blood-feeding, during which time females apparently fed on sugar solutions. Maximum biting densities of nullipars in May and September showed that A. claviger was bivoltine. The physiological age structure of the population showed that most parous adults at bait had oviposited only once or twice, but a few females had laid four batches. Live Hygrobatid-type mites proved reliable in indicating nulliparity. Mature larvae developed in the eggs 5–7 days after oviposition and while most eggs hatched within the next three days, a few remained unhatched until the 30th day. Females of the second generation (September) laid fewer eggs than those of the first generation (May). About six days were required for blood digestion, and females supplied with sugar were able to live 46 days. The marked delays between successive gonotrophic cycles in natural populations would make parous rates unreliable for the estimation of daily mortalities.

The sheep headfly, Hydrotaea irritans (Fallén) (Diptera: Muscidae): biology of immature stages in the soil

1979 ◽  
Vol 69 (4) ◽  
pp. 589-598 ◽  
Author(s):  
J. Robinson
Keyword(s):  
Open Field ◽  
Total Population ◽  
Larval Habitat ◽  
Immature Stages ◽  
Pasture Soil ◽  
Males And Females ◽  
Single Field

AbstractSampling in Northumberland, England, and southern Scotland of pasture soils, the major larval habitat of Hydrotaea irritans (Fall.), showed larvel densities of between 0 and 30/m2; 15 different sites were examined, and all produced larvae. Larvae were found from September until June, larvael development continuing in the soil for about eight months. A study of the distribution within a single field that larvae were not confined to the wooded margins but occurred in significant numbers throughout the field. Higher numbers of larvae were present in the soil beneath cow pats than in the open field, but the proportion relative to the total population is small. Larvae prey was predominantly dipterous and coleopterous larvae. Pupation took place in the top 5 cm of pasture soil during May and lasted until late June. Emergence of adults took place from June until late July; males and females emerged over the same period

scholarly journals Aestivation in apple leafcurling midge (Diptera Cecidomyiidae) parasitoid Platygaster demades Walker (Hymenoptera Platygastridae)

2007 ◽  
Vol 60 ◽  
pp. 21-25 ◽  
Author(s):  
X.Z. He ◽  
Q. Wang
Keyword(s):  
First Generation ◽  
Second Generation ◽  
Egg Parasitoid ◽  
Fourth Generation ◽  
Third Generation ◽  
Immature Stages ◽  
Natural Conditions ◽  
The Third ◽  
Emergence Patterns ◽  
Dasineura Mali

This study reports an investigation on the aestivation and overwintering strategies of Platygaster demades an egg parasitoid of apple leafcurling midge (ALCM) Dasineura mali under natural conditions during 2005 2006 The first three generations of ALCM developed into adults during the springautumn of 2005/2006 and the fourth generation overwintered as larvae All first generation P demades emerged in the spring of 2005 About 64 of live individuals of P demades in the second generation and 38 in the third generation entered aestivation as eggs which hatched in mid March and early May 2006 respectively Parasitoid eggs of the fourth generation started to hatch four weeks after the parasitised ALCM larvae entered the soil The aestivated and fourth generation parasitoids overwintered as immature stages and started emerging in late September 2006 The emergence patterns of overwintered parasitoids and ALCM were highly synchronized in the following season

From the Oort cloud to Halley-type comets

1999 ◽  
Vol 173 ◽  
pp. 327-338 ◽  
Author(s):  
J.A. Fernández ◽  
T. Gallardo
Keyword(s):  
Total Population ◽  
Complex Function ◽  
Dynamical Evolution ◽  
Oort Cloud ◽  
Capture Process ◽  
Influx Rate ◽  
Short Period ◽  
Dynamical Properties ◽  
Orbital Periods ◽  
Probability Of Capture

AbstractThe Oort cloud probably is the source of Halley-type (HT) comets and perhaps of some Jupiter-family (JF) comets. The process of capture of Oort cloud comets into HT comets by planetary perturbations and its efficiency are very important problems in comet ary dynamics. A small fraction of comets coming from the Oort cloud − of about 10−2− are found to become HT comets (orbital periods < 200 yr). The steady-state population of HT comets is a complex function of the influx rate of new comets, the probability of capture and their physical lifetimes. From the discovery rate of active HT comets, their total population can be estimated to be of a few hundreds for perihelion distancesq <2 AU. Randomly-oriented LP comets captured into short-period orbits (orbital periods < 20 yr) show dynamical properties that do not match the observed properties of JF comets, in particular the distribution of their orbital inclinations, so Oort cloud comets can be ruled out as a suitable source for most JF comets. The scope of this presentation is to review the capture process of new comets into HT and short-period orbits, including the possibility that some of them may become sungrazers during their dynamical evolution.

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