Investigations on the Cotton Bollworm, Heliothis armigera, Hübn. (obsoleta, Fabr.)

1939 ◽  
Vol 30 (3) ◽  
pp. 321-338 ◽  
Author(s):  
F. S. Parsons
Keyword(s):  
Heliothis Armigera ◽  
Climatic Conditions ◽  
Continuous Operation ◽  
Food Plant ◽  
Cotton Bollworm ◽  
Natural Food ◽  
Food Crops ◽  
Quantitative Survey ◽  
Cotton Pest

Methods for the quantitative survey of the incidence of Heliothis armigera have been in continuous operation in the Barberton area of the Eastern Transvaal from 1929 to the present; since 1933 the Survey was operated similarly in Swaziland and Northern Natal.It was accepted early that the bollworm situation in cotton, which primarily it was desired to ameliorate, depends largely upon the influences exerted by other food-crops of the insect grown prior to and in association with cotton, and the investigations were instituted with a view to acquiring the fullest information on the incidence, habits and reactions of H. armigera with respect to the chain of cultivated and natural food-plant situations existing under differing climatic conditions in the course of the year.The present paper is the first of a series communicating the results of investigations which proceed in various directions from information supplied by the Cotton Pest Survey centred upon Barberton. The paper deals with the annual course of bollworm incidence as indicated, in the first instance, by egg counts taken twice-weekly, year by year, in examples of all food-plant situations according to methods of sampling and calculation devised here.

Investigations on the Cotton Bollworm, Heliothis armigera, Hübn

1940 ◽  
Vol 31 (2) ◽  
pp. 147-177 ◽  
Author(s):  
F. S. Parsons
Keyword(s):  
Heliothis Armigera ◽  
Egg Laying ◽  
Food Plant ◽  
Cotton Bollworm ◽  
Flowering Period ◽  
Flower Production ◽  
Plant Associations ◽  
The Given

Studies of the food-plant associations of Heliothis armigera have elicited the information that, for all practical purposes, egg-laying may be considered as confined to the period of florescence. Evidence of coincidence of the oviposition and flowering curves is submitted for 21 species of short-flowering crops and 8 species of long-flowering crops. All told, records taken in nearly 1,000 crops have been consulted for the conclusions drawn.As regards short-flowering species, the peaks, as well as the confines, of the oviposition and flowering curves are related closely. But oviposition on long-flowering species may decline while flowering is still in progress, or two or more waves of oviposition may be evident according to the number of moth flights spanned by the flowering period. The courses of oviposition on long-flowering species of crop in the given instances are interpreted through knowledge of the train of moth flights: although egg-laying in quantity occurs within the flowering period, peak layings frequently are not aligned with maximum flower production because the calendar times of moth flights are displaced in relation thereto.

Identification of the sex pheromone of the cotton bollworm,Heliothis armigera, in Israel

1980 ◽  
Vol 8 (3) ◽  
pp. 209-211 ◽  
Author(s):  
E. Dunkelblum ◽  
S. Gothilf ◽  
M. Kehat
Keyword(s):  
Sex Pheromone ◽  
Heliothis Armigera ◽  
Cotton Bollworm

The Feasibility of Producing Green Energy Crops on Pb-Contaminated Soil

2013 ◽  
Vol 739 ◽  
pp. 332-335
Author(s):  
Shu Fen Cheng ◽  
Chin Yuan Huang ◽  
Yao Ting Tu ◽  
Sheng Jie Lin ◽  
Guo Lin Chen ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Contaminated Soil ◽  
Agricultural Land ◽  
Absorption Capacity ◽  
Climatic Conditions ◽  
Green Energy ◽  
Energy Crops ◽  
Biomass Energy ◽  
Food Crops ◽  
Green Remediation

For the agricultural land contaminated by heavy metal and thus not suitable for growing food crops, combining green crops with phytoremediation technology can provide more green energy crops and implement the soil remediation through a more economic green remediation method. This study selected three crops, which are rich in biomass energy and are suitable to grow in the climatic conditions of Taiwan, namely corn, soybean and peanut, for Pb-contaminated soil situ vegetation planting tests. The results show that the production of biomass by corn was the highest and each plant could produce 1248 g on average, followed by peanut with the average 470.2 g, soybean only 17.6 g. Regarding Pb absorption capacity, each corn could absorb 87.1 mg; peanut 125.3 mg; and soybean only 5.9 mg. Soybean is not feasible because the low biomass production and the total Pb absorption are far lower than those of corn and peanut.

Investigations on Heliothis armigera (HB.) in Uganda

1959 ◽  
Vol 50 (3) ◽  
pp. 487-506 ◽  
Author(s):  
T. H. Coaker
Keyword(s):  
Virus Disease ◽  
Heliothis Armigera ◽  
Climatic Conditions ◽  
Food Plants ◽  
Research Station ◽  
Larval Feeding ◽  
Trap Crops ◽  
Preoviposition Period ◽  
Wild Host ◽  
The Mean

A survey of the populations of eggs and larvae of Heliothis armigera (Hb.) was made on the Cotton Research Station, Namulonge, in Buganda Province, Uganda, over the four-year period, 1954–57 inclusive, on cotton, maize, groundnuts, beans and, in one year, sunflower. The populations encountered were low in comparison with some other cotton areas in Africa. The oviposition rate on each crop closely followed the flowering cycle, and there was no indication of the population from one crop influencing that on a subsequent crop, even when their flowering cycles overlapped. Under the normal crop sequence there is a sufficient gap between the attractive phases of successive crops to cause dispersal, possibly to wild host-plants, of the moths emerging from pupae bred in the preceding crop.The variation in population from year to year on a given crop was no greater than that between different localities in any one season. Maize and sunflower did not prove successful when tested as trap crops grown adjacent to cotton.Earias spp. and Argyroploce leucotreta Meyr. were less abundant than Heliothis and together constituted only 27 per cent, of the total population of Lepidopterous larvae on cotton.A method is described for breeding H. armigera, in the laboratory, in which the mean duration of the various stages was: egg, 4 days; larva, 24·8 days; pupa, 22·9 days; preoviposition period, 3·1 days; and oviposition period, 10·4 days. The mean number of eggs laid per female was 751·6, of which 71·4 per cent, hatched. Larval diets consisting of differing species and parts of food-plants caused significant differences in larval and pupal periods, the former being least (21·8 days) on maize silks and greatest (33·6 days) on sunflower corolla and receptacle, and the latter least (19·7 days) after larval feeding on three-week-old maize cobs and greatest (26 days) after seven-week-old cotton bolls. Pupae developing from larvae collected from the field did not exhibit any diapause or resting stage.Two egg parasites and 15 larval parasites (three of which were probably secondary) were bred from material of H. armigera collected in the field, but the degree of parasitism remained low throughout the year. A nuclear polyhedral virus disease of the larvae was also recorded.It is concluded that under the climatic conditions encountered, H. armigera is active throughout the year because wild or cultivated food-plants are always available and no resting stage of the insect is induced; this continuous activity is accompanied by biologically controlling factors that maintain populations stable at a relatively low level.

Panorama of the Strategy for Managing the Risk Created by the Weather-Related and Outside Force Threat in VIT-Ecopetrol

2015 ◽  
Author(s):  
Jaime Hernán Aristizábal Ceballos ◽  
Julián Fernando Chaves Agudelo
Keyword(s):  
Management Strategy ◽  
Vice President ◽  
Climatic Conditions ◽  
Continuous Operation ◽  
Operating Efficiency ◽  
Transmission Systems ◽  
Anthropic Impact ◽  
Risk Levels ◽  
Comprehensive Management ◽  
Social Environmental

The realization of the weather-related and outside force threat has historically caused losses of containment with their subsequent social, environmental, economic and image consequences for Ecopetrol. The zones in which these phenomena occur are characterized by the interaction of transmission systems with an environment that is complex in its topographical, geological-geomorphological and climatic conditions, and because of the anthropic impact of changes in land use. In Ecopetrol’s office of the Vice-president for Transportation Logistics (VIT-Ecopetrol), a threat management strategy has been proposed that seeks to minimize the vulnerability of the pipelines to processes that can impact on operating efficiency or that, because of their degree of complexity, require comprehensive management in order to guarantee operation at tolerable levels of risk. This article presents a panorama of the work performed with regard to the validation of the threat and risk levels of the assets, the internal analyses performed by geotechnical professionals for formulating the plans for the management of assets and the accompaniment of such in order to achieve the continuous operation of the transmission systems.

scholarly journals Inventory of the Different Methods of Natural Conservation of Food Crops Used in the Markets of Daloa (Ivory Coast)

2021 ◽  
Vol 10 (10) ◽  
pp. 1-10
Author(s):  
DEFFAN Zranseu Ange Bénédicte MASSE Diomandé ◽  
YAPI Jocelyn Constant BEUGRE Grah Avit Maxwell
Keyword(s):  
Ivory Coast ◽  
Natural Food ◽  
Cash Income ◽  
Food Crops ◽  
Food Crop ◽  
Chemical Parameters ◽  
Food Sector ◽  
Preservation Method ◽  
Rural And Urban ◽  
Physico Chemical

Food in West Africa is one of the main sources of cash income. It plays an important role in feeding populations (rural and urban). These vegetables are very perishable foods, and generally seasonal, causing several post-harvest losses. Lack of knowledge of the natural techniques used by our peasants to conserve their various crops hampers their application, as well as their popularization. It is with this in mind that this study was initiated. It is based first of all on a survey carried out on large markets and supermarkets in the commune of Daloa (Ivory Coast), with a view to identifying the most widely used natural food conservation methods. It appears from these surveys that the open air preservation method was the most common at 80%. This method is widely used on eggplants (42.29%), tomatoes (33.66%) and okra (24.05%) in the markets. This method could favor certain physico-chemical parameters of the food crop to the detriment of others. The results of surveys carried out in the field have made it possible to show the need to popularize the food sector by training our various producers and sellers in order to know the basic basics of conservation.

scholarly journals Climate and topographic controls on simulated pasture production in a semiarid Mediterranean watershed with scattered tree cover

2014 ◽  
Vol 18 (4) ◽  
pp. 1439-1456 ◽  
Author(s):  
J. Lozano-Parra ◽  
M. P. Maneta ◽  
S. Schnabel
Keyword(s):  
Critical Role ◽  
Climatic Conditions ◽  
Tree Canopy ◽  
Tree Cover ◽  
Natural Food ◽  
Climate Data ◽  
Data Set ◽  
Stochastic Weather Generator ◽  
Pasture Production ◽  
Tree Canopy Cover

Abstract. Natural grasses in semiarid rangelands constitute an effective protection against soil erosion and degradation, are a source of natural food for livestock and play a critical role in the hydrologic cycle by contributing to the uptake and transpiration of water. However, natural pastures are threatened by land abandonment and the consequent encroachment of shrubs and trees as well as by changing climatic conditions. In spite of their ecological and economic importance, the spatiotemporal variations of pasture production at the decadal–century scales over whole watersheds are poorly known. We used a physically based, spatially distributed ecohydrologic model applied to a 99.5 ha semiarid watershed in western Spain to investigate the sensitivity of pasture production to climate variability. The ecohydrologic model was run using a 300-year-long synthetic daily climate data set generated using a stochastic weather generator. The data set reproduced the range of climatic variations observed under the current climate. Results indicated that variation of pasture production largely depended on factors that also determined the availability of soil moisture such as the temporal distribution of precipitation, topography, and tree canopy cover. The latter is negatively related with production, reflecting the importance of rainfall and light interception, as well as water consumption by trees. Valley bottoms and flat areas in the lower parts of the catchment are characterized by higher pasture production but more interannual variability. A quantitative assessment of the quality of the simulations showed that ecohydrologic models are a valuable tool to investigate long-term (century scale) water and energy fluxes, as well as vegetation dynamics, in semiarid rangelands.

Sign in / Sign up

Export Citation Format

Share Document