ASSESSMENT OF TOBACCO LOSSES CAUSED BY THE DARK-SIDED CUTWORM, EUXOA MESSORIA (LEPIDOPTERA: NOCTUIDAE), DELHI, ONTARIO

1971 ◽  
Vol 103 (4) ◽  
pp. 534-541 ◽  
Author(s):  
H. H. Cheng
Keyword(s):  
Population Density ◽  
Tobacco Plant ◽  
New Method ◽  
Crop Losses ◽  
Euxoa Messoria ◽  
Average Current ◽  
Lepidoptera Noctuidae

AbstractIntensive studies on the damage and losses of flue-cured tobacco caused by the dark-sided cutworm, Euxoa messoria (Harris), were carried out in the field at Delhi, Ont., during 1967 and 1968. A new method for estimating the accurate tobacco crop losses is illustrated. Assessment of damage of the tobacco plant and the population density in relation to the yield are described. The yield was significantly related, negatively, to the dark-sided cutworm density, and was reduced in the cutworm-damaged blocks in comparison with the yield in the undamaged check blocks. Assessment of average losses caused by the species was 17% of marketable tobacco, which, based on the average current prices, would amount to 200 dollars per acre or approximately 25 million dollars over the country as a whole every year.

CUTWORMS (LEPIDOPTERA: NOCTUIDAE) OF TOBACCO IN NOVA SCOTIA: II. FALL RYE AND WINTER FALLOW EFFECTS ON A FIELD POPULATION

1974 ◽  
Vol 106 (1) ◽  
pp. 73-77
Author(s):  
H. B. Specht
Keyword(s):  
Nova Scotia ◽  
Winter Rye ◽  
Tobacco Plants ◽  
Peridroma Saucia ◽  
Cultural Methods ◽  
Variegated Cutworm ◽  
Euxoa Messoria ◽  
Field Plots ◽  
Lepidoptera Noctuidae ◽  
Winter Fallow

AbstractTwice as many larvae of the dark-sided cutworm, Euxoa messoria Harr., were found in rye fall-seeded tobacco field plots than in winter-fallowed tobacco field plots. There were corresponding differences in numbers of injured tobacco plants. Cutworm aggregations were more prominent in the winter rye than in the winter fallowed area of the tobacco field with low populations of dark-sided cutworms.Larvae of the variegated cutworm, Peridroma saucia Hbn., appeared 2 to 4 weeks later than dark-sided cutworm larvae and winter cultural methods had little effect on their numbers.

scholarly journals Larval densities of the protected Striped lychnis moth Shargacucullia lychnis (Lepidoptera: Noctuidae) in Buckinghamshire

2021 ◽  
Author(s):  
Juliano Morimoto ◽  
Lucy Kerr
Keyword(s):  
Natural History ◽  
Population Density ◽  
Developmental Stages ◽  
Larval Density ◽  
Natural Populations ◽  
Adaptive Responses ◽  
Larval Population ◽  
History Information ◽  
The Uk ◽  
Lepidoptera Noctuidae

Natural history information is essential for ecologically-relevant inferences about (adaptive) responses in organismal biology. Yet, natural history data can be difficult to obtain, particularly for the developmental stages of holometabolous insects. This gap can compromise our ability to design controlled experiments that provide useful understanding of insect responses to changing environments and precludes our ability to understand how natural populations may respond to unpredictable climatic changes in their natural environment. In this study, we collated data from previous reports from the Butterfly Conservation Upper Thames Branch on the larval population density of Shargacucullia lychnis (Lepidoptera: Noctuidae) in Buckinghamshire. In the UK, S. lychnis is a protected species, for which natural history information can be invaluable for its effective conservation. We report here that the natural range of larval densities observed for S. lychnis across locations and years is 0.001 to 6.417 larvae per spike. More importantly, S. lychnis larval density has overall declined from 1996 to 2020, which could support previous reports of a contraction in population range for this species. Overall, this study provides invaluable information about larval population density for an important protected Lepidopteran species of the UK.

OVIPOSITION AND LONGEVITY OF THE DARK-SIDED CUTWORM, EUXOA MESSORIA (LEPIDOPTERA: NOCTUIDAE), IN THE LABORATORY

1972 ◽  
Vol 104 (6) ◽  
pp. 919-925 ◽  
Author(s):  
H. H. Cheng
Keyword(s):  
Oviposition Period ◽  
Male And Female ◽  
Significant Difference ◽  
Euxoa Messoria ◽  
The Mean ◽  
Honey Solution ◽  
Lepidoptera Noctuidae ◽  
Adult Food

AbstractIn the laboratory, the mean number of eggs laid per female of the dark-sided cutworm, Euxoa messoria (Harris), fed on honey solution was 1303.8; when given water alone 261.3; and 86.4 when held without food or water. Adult food significantly increased the longevity and oviposition period and reduced the pre-oviposition period. There was no significant difference between the weight of male and female pupae. The weight of the female pupae was significantly correlated with: the oviposition period; the number of eggs laid; the longevity, except moths fed on honey solution; but not the pre-oviposition period, regardless of food taken as adults. Females fed on honey solution mated successfully, 30% of them more than once. When given water or nothing the number of mated females was reduced. Dissections showed that adult food accelerated the development of eggs and increased the fecundity potential.

INSECT PARASITES OF THE DARKSIDED CUTWORM, EUXOA MESSORIA (LEPIDOPTERA: NOCTUIDAE), IN ONTARIO

1977 ◽  
Vol 109 (1) ◽  
pp. 137-142 ◽  
Author(s):  
H. H. Cheng
Keyword(s):  
Internal Parasites ◽  
Host Parasite Relationship ◽  
Parasite Relationship ◽  
Euxoa Messoria ◽  
Host Parasite ◽  
Lepidoptera Noctuidae ◽  
Insect Parasites

AbstractIn the study of insect parasites of the darksided cutworm, Euxoa messoria (Harris), fourth- to seventh-instar larvae were collected from a field at Delhi, Ont., and reared in the laboratory. A total of 701 insect parasites including six species of Hymenoptera and four of Diptera, were reared from the 3970 darksided cutworm larvae collected in 1973 and 1974.Thirteen species of insect parasites of E. messoria are listed. Ten of these species were reared in the present study from E. messoria in Ontario and all of them are primary and internal parasites. Of the 10, only two have previously been reported as parasites of E. messoria. Host–parasite relationship and the degree of parasitism are given for the 10 species reared in Ontario.

scholarly journals A vidék és a vidéki térségek meghatározásának európai vonatkozásai

2011 ◽  
Vol 6 (1-2) ◽  
pp. 105-112
Author(s):  
Krisztián Kis
Keyword(s):  
Land Use ◽  
Population Density ◽  
European Commission ◽  
Rural Areas ◽  
Relevant Information ◽  
New Method ◽  
Economic Indicators ◽  
Urban And Rural Areas

The paper reviews the European attempts to designate rural areas, major institutional definitions and the existing practice. The presented rural designations are mostly recommendations, serving statistical purposes, but in neither case constitute as designation for development. Designations for this purpose are under national competence, during which the characteristics of settlement structures, population density, land use and certain socio-economic indicators are taken into account. Whatever approach we take in designating rural areas or defining rural, we need to have relevant information capturing characteristics of rural areas, as well as such geographic units which help to perform rural designation. To this end the European Commission recently introduced a new method, which allows designating urban and rural areas more precisely.

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