ABUNDANCE, WINTER SURVIVAL, AND SPRING EMERGENCE OF FLEA BEETLES (COLEOPTERA: CHRYSOMELIDAE) IN A MANITOBA GROVE

1987 ◽  
Vol 119 (5) ◽  
pp. 419-426 ◽  
Author(s):  
W.J. Turnock ◽  
R.J. Lamb ◽  
R.J. Bilodeau
Keyword(s):  
Random Distribution ◽  
Late Summer ◽  
Abundant Species ◽  
Cold Weather ◽  
Phyllotreta Cruciferae ◽  
The North ◽  
Flea Beetles ◽  
North Side ◽  
Spring Emergence ◽  
Adult Flea

AbstractAdult flea beetles, Phyllotreta cruciferae (Goeze), P. striolata (F.), and Psylliodes punctulata Melsh., overwintering in the litter of a riverbank forest at Winnipeg, Manitoba, varied in density from about 1.4 million to 2.5 million beetles per hectare from 1979 to 1983. Phyllotreta cruciferae was the most abundant species (78–92%) and P. striolata next (6–22%) in litter samples collected in the late autumn, just before the ground froze. The distribution of beetles was highly aggregated (variance/mean ratio > 1.0) for P. cruciferae and P. striolata in years of high density but this ratio was 1.0 (random distribution) when densities were below 1.0 per square metre. Density was positively related to the amount of litter and increased from the edge to the center on the south side of the grove. On the north side, densities were highest at the edge of the grove. Survival in the litter during the autumn was generally lower and more variable than during the winter or spring periods. Survival in the litter during the 4 years ranged from 0.22 to 0.46 for P. cruciferae and from 0.31 to 0.83 for P. striolata. Temperature, through its effect on the time of emergence of adults in late summer and autumn, may affect their ability to survive the onset of cold weather.

FLEA BEETLES (COLEOPTERA: CHRYSOMELIDAE) ATTACKING RAPE CROPS IN THE CANADIAN PRAIRIE PROVINCES

1977 ◽  
Vol 109 (1) ◽  
pp. 21-32 ◽  
Author(s):  
L. Burgess
Keyword(s):  
Flea Beetle ◽  
Late Summer ◽  
Egg Laying ◽  
Canadian Prairie ◽  
Phyllotreta Cruciferae ◽  
Phyllotreta Striolata ◽  
Flea Beetles ◽  
New Generation ◽  
Adult Flea ◽  
Prairie Provinces

AbstractAdults of five species of flea beetles were found attacking rape crops (Brassica napusL. andBrassica campestrisL.) in the Canadian prairie provinces from 1971 to 1974.Phyllotreta cruciferae(Goeze) was the most abundant and serious pest, followed in order byPsylliodes punctulataMelsh. andPhyllotreta striolata(F.) (=vittata(F.)), whilePhyllotreta albionica(Lec.) andPhyllotreta robustaLec. were present only occasionally. The fourPhyllotretaspecies confined their feeding largely to cruciferous plants, butPsyl.punctulatahad a broader host range. All of the five species overwintered as adults, usually in leaf litter or turf beneath hedges, poplar groves, or fencerows, or sometimes in the soil in fields, and all became active with the arrival of warm sunny weather in the spring, withPsyl.punctulatausually being the first to appear. All appeared to have but one generation per year, with mating and egg laying occurring in the spring, the larvae inhabiting the soil and feeding on host-plant roots, and the new generation of adults emerging from pupae in the soil in late July and in August. The overwintered adults usually died in late June or early July, so there was a period in July when adult flea beetles were scarce. The most serious damage to rape crops by flea beetles was caused by overwintered adults attacking seedling crops in the spring; movement of these beetles into crops took the form of a creeping infestation moving from plant to plant into the field from nearby volunteer rape of cruciferous weed feeding grounds, or a more rapid and even infestation of a whole field with flight probably being the major method of movement. Flea beetles fed most actively when the weather was sunny, warm, and dry; cool damp weather reduced the intensity of attack and aided plant growth. Shade, such as exists in a healthy stand of rape beyond the pre-bloom stage, also inhibited attack. Occasionally, late-maturing rape crops were damaged in late summer by new generation adult flea beetles, particularlyP.cruciferae, feeding on the green epidermis of the stems, leaves, and pods.A field key for separating the five flea beetle species attacking rape crops in the Canadian prairie provinces is given.

Abundance, growth and first-winter survival of young bass in nurseries of south-west England

2002 ◽  
Vol 82 (2) ◽  
pp. 307-319 ◽  
Author(s):  
Donovan Kelley
Keyword(s):  
Stomach Contents ◽  
Late Summer ◽  
Winter Survival ◽  
Cold Spell ◽  
The South ◽  
South Side ◽  
The North ◽  
North Side ◽  
South West ◽  
South West England

0-group bass were sampled from the shallow creeks of the Tamar and Camel estuaries at regular intervals from May to September in 1981 to 2000 to measure relative year-class abundance. From 1989 onwards classes were generally strong, especially those of 1989, 1992 (Tamar only), 1995 and 1998. Sampling at age-4, before departure from the nursery at the onset of adolescent movements, gave broadly similar relativities. Numbers were greater, and growth faster, in the Tamar than in the smaller and cooler Camel. Temperature was an important factor in both abundance and growth. Occasional major differences in abundance between the two estuaries were reported. Factors which might bias the age-4 result are considered. Other estuaries on the south side of the south-west peninsula, sampled less frequently, reflected Tamar abundances; others on the north side reflected Camel abundances. Limited analysis of stomach contents of older juvenile bass often present in the same habitats revealed no evidence of cannibalism on 0-groups. The shallow creeks of the Tamar and Camel were deserted in winter but a deeper creek on the Taw, frequented throughout winter, was sampled monthly in the 1982–1996 winters to measure losses, if any, in cold periods. In the mainly mild winters, losses were infrequent and small except in the five-week cold spell of early 1986, when the 1985 class suffered an estimated 58% loss in the Taw and possible total loss in the Camel and the Tamar. Sudden heavy flooding of the estuaries caused no apparent losses when they occurred in late summer and autumn but might be damaging if they occur soon after post-larvae arrive.

EFFECT OF POST-TREATMENT TEMPERATURE ON THE CONTACT TOXICITY OF CYPERMETHRIN SPRAY TO ADULTS OF THE FLEA BEETLE, PHYLLOTRETA CRUCIFERAE (GOEZE)

1986 ◽  
Vol 118 (1) ◽  
pp. 79-80
Author(s):  
L. Burgess ◽  
C.F. Hinks
Keyword(s):  
Flea Beetle ◽  
Treatment Temperature ◽  
Synthetic Pyrethroid ◽  
Post Treatment ◽  
Contact Toxicity ◽  
Pest Species ◽  
Phyllotreta Cruciferae ◽  
Flea Beetles ◽  
Major Pest ◽  
Adult Flea

In 1982, the synthetic pyrethroid, cypermethrin, was among the insecticides recommended as a spray for control of adult flea beetles attacking canola crops in Saskatchewan (Saskatchewan Agriculture 1982). Growers reported some problems with its effectiveness at the recommended rates of 14–20 g AI/ha, however, and the recommendation for its use against flea beetles was subsequently discontinued. Laboratory spray trials were begun in 1982 to determine if post-treatment temperature affected the contact toxicity of cypermethrin to adults of the major pest species, Phyllotreta cruciferae (Goeze), and if the dosage that had been recommended was adequate as a contact spray.

PREDATION ON ADULTS OF THE FLEA BEETLE PHYLLOTRETA CRUCIFERAE BY LACEWING LARVAE (NEUROPTERA: CHRYSOPIDAE)

1980 ◽  
Vol 112 (7) ◽  
pp. 745-746 ◽  
Author(s):  
L. Burgess
Keyword(s):  
Plutella Xylostella ◽  
Diamondback Moth ◽  
Flea Beetle ◽  
Canadian Prairie ◽  
Phyllotreta Cruciferae ◽  
Flea Beetles ◽  
Insect Predators ◽  
Sweep Net ◽  
Adult Flea ◽  
Prairie Provinces

Several instances of predation by lacewing larvae on adults of the flea beetle Phyllotreta cruciferae (Goeze) have been observed in Saskatchewan. Other reported insect predators of rapeseed-crop-infesting flea beetles in the Canadian prairie provinces are the beetle Collops vittatus Say (Gerber and Osgood 1975), and one of the big-eyed bugs, Geocoris bullatus (Say) (Burgess 1977).The first observation of an attack on an adult flea beetle by a lacewing larva was in August 1972, when some lacewing larvae, adult flea beetles, diamondback moth larvae (Plutella xylostella (L.)) and unidentified aphids and midges were swept from maturing rapeseed near Aberdeen, Saskatchewan. One of these lacewing larvae attacked an adult of P. cruczferae in a glass collecting-vial and carried the flea beetle around in its jaws. Other lacewing larvae attacked aphids, midges, and diamondback moth larvae. Further evidence for lacewing larvae feeding on adult flea beetles was obtained in August 1979, when a sizeable population of lacewing larvae in a rapeseed crop was encountered near St. Gregor, Saskatchewan. One of the larvae swept from this crop had an adult of P. cruciferae in its jaws when it was first seen in the sweep net. Later the same day, another lacewing larva, swept from a nearby rapeseed field, attacked an adult of P. cruciferae in a collecting vial. In the laboratory both lacewing larvae, still carrying their prey, were quick-frozen, preserved in 70% ethanol and later photographed.

PREDATION ON ADULT PHYLLOTRETA FLEA BEETLES BY PODISUS MACULIVENTRIS (HEMIPTERA: PENTATOMIDAE) AND NABICULA AMERICOLIMBATA (HEMIPTERA: NABIDAE)

1986 ◽  
Vol 118 (7) ◽  
pp. 731-732 ◽  
Author(s):  
Thomas W. Culliney
Keyword(s):  
New York ◽  
New York State ◽  
First Record ◽  
Arthropod Community ◽  
Podisus Maculiventris ◽  
Phyllotreta Cruciferae ◽  
Flea Beetles ◽  
Central New York ◽  
Insect Predators ◽  
Adult Flea

On three occasions in late August 1985, during the course of a study of the arthropod community associated with collards (Brassica oleracea var. acephala) (Cruciferae) in central New York State, two species of predaceous Heteroptera, the spined soldier bug, Podisus maculiventris (Say), and Nabicula americolimbata (Carayon), were observed feeding on adult flea beetles of the genus Phyllotreta. Evidence for predation on adult flea beetles is rare. Tahvanainen and Root (1972) and Kareiva (1985) reported practically no predation on adult Phyllotreta cruciferae (Goeze) in central New York, but scattered observations in Canada have documented occasional attacks on adult crucifer-infesting flea beetles by various insect predators (Gerber and Osgood 1975; Burgess 1977, 1980, 1982). This is the first record of predation on adult flea beetles by P. muculiventris and N. americolimbata. Burgess (1982) noted predation on adult P. cruciferae by another nabid, Nabis alternatus Parshley.

ANTIBIOSIS OF PREFERRED AND NON-PREFERRED HOST-PLANTS FOR THE FLEA BEETLE, PHYLLOTRETA CRUCIFERAE (GOEZE) (COLEOPTERA: CHRYSOMELIDAE)

1997 ◽  
Vol 129 (1) ◽  
pp. 43-49 ◽  
Author(s):  
P. Palaniswamy ◽  
R.J. Lamb ◽  
R.P. Bodnaryk
Keyword(s):  
Host Plants ◽  
Flea Beetle ◽  
Dry Weight ◽  
Sinapis Alba ◽  
Early Spring ◽  
Phyllotreta Cruciferae ◽  
Thlaspi Arvense ◽  
Flea Beetles ◽  
Adult Flea ◽  
Promising Type

AbstractThe antibiosis of crucifers to flea beetles, Phyllotreta cruciferae (Goeze), was compared for Brassica juncea L., B. napus L., and B. rapa L. with low antixenosis, B. carinata L. and Sinapis alba L. with moderate antixenosis, and Thlaspi arvense L. with high antixenosis. Adult flea beetles collected from the field in early spring fed actively on intact or excised leaves of all plants except T. arvense. The beetles survived, and gained weight and fat on the Brassica species and S. alba, but not on intact foliage of T. arvense. No antibiosis was detected in any of the Brassica species or in S. alba. Intact foliage of T. arvense was so antixenotic that beetles probably starved rather than suffered from antibiosis. A low level of antibiosis was detected in excised foliage of T. arvense where the antixenosis was lost. These experiments show that estimates of beetle survival, dry weight, and fat content can be used in the laboratory to test small numbers of candidate plants for antibiosis. However, the level of antibiosis appears to vary less among Brassica species and related plants than does the level of antixenosis, and so the latter is a more promising type of resistance for use against flea beetles in canola.

Feeding and predation impact of chaetognaths in the north Aegean Sea (Strymonikos and Ierissos Gulfs)

2005 ◽  
Vol 85 (6) ◽  
pp. 1525-1532 ◽  
Author(s):  
George Kehayias ◽  
Evangelia Michaloudi ◽  
Emmanuil Koutrakis
Keyword(s):  
Standing Stock ◽  
Late Summer ◽  
Aegean Sea ◽  
Abundant Species ◽  
Immature Stage ◽  
Stage I ◽  
Breeding Period ◽  
The North ◽  
North Aegean ◽  
North Aegean Sea

The feeding of the most important chaetognath species (Sagitta enflata, Sagitta minima, Sagitta setosa and Sagitta serratodentata) found in a grid of 35 stations in the north Aegean Sea (Strymonikos and Ierissos Gulfs) was investigated through gut content analysis during five sampling periods from June 1997 to May 1998. Sagitta enflata and S. minima were the most abundant species in summer–autumn 1997 and in spring 1998, respectively. Copepods were the main food for all chaetognath species in spring 1998, while cladocerans in summer–autumn 1997 dominated the diet, especially of S. enflata. In September 1997, the juvenile specimens of cladocerans were the most important prey of the immature Stage I specimens of S. enflata, which resulted from the major breeding period in late summer. The estimated impact of chaetognath predation on the copepod and cladoceran communities ranged between 0.02–2.76% and 0.01–1.29% of the copepod and cladoceran standing stock, respectively. Stage I specimens of S. enflata accounted for nearly 90% of the total copepod and cladoceran standing stock consumed per day by the total population of this species in September 1997.

A Radiocarbon-dated Collared Urn from Oban

2001 ◽  
Vol 23 (2) ◽  
pp. 105-118
Author(s):  
CHRISTOPHER LOWE ◽  
ANN MacSWEEN ◽  
KATHLEEN McSWEENEY
Keyword(s):  
The North ◽  
North Side ◽  
Funerary Ritual

A collared urn was found during the course of a watching-brief on the raised beach on the north side of Oban bay. Post-excavation analysis has succeeded in throwing some further light on the chronology of this type of urn and possibly on some elements of the funerary ritual associated with its burial. The same watching-brief also revealed the site of a truncated pit of medieval date, filled with fire-cracked stones.

Sign in / Sign up

Export Citation Format

Share Document