ORTHOSIA HIBISCI GUENÉE (LEPIDOPTERA: NOCTUIDAE): INDIGENOUS PARASITOIDS AND THE IMPACT OF EARINUS LIMITARUS (SAY) (HYMENOPTERA: ICHNEUMONIDAE) ON ITS HOST FEEDING ACTIVITY

1995 ◽  
Vol 127 (4) ◽  
pp. 473-477 ◽  
Author(s):  
J.E. Cossentine ◽  
L.B. Jensen
Keyword(s):  
British Columbia ◽  
Feeding Activity ◽  
Host Feeding ◽  
Feeding Damage ◽  
The South ◽  
Minor Significance ◽  
Compsilura Concinnata ◽  
The Impact ◽  
Lepidoptera Noctuidae ◽  
Indigenous Parasitoids

AbstractA 3-year survey of apple and cherry orchards in the interior of British Columbia revealed that speckled green fruitworm, Orthosia hibisci, is the dominant fruitworm species in the south of the Okanagan Valley. Larvae of speckled green fruitworm collected from orchards that used no or minimal insecticides experienced 22.5–29.0% parasitism in 1988–1990. Earinus limitarus was responsible for 98.9% of the parasitism in the 3 years. Parasitoids of minor significance included a Meteorus sp. (Hymenoptera: Braconidae) and Compsilura concinnata (Mg.) (Diptera: Tachinidae). Data from laboratory trials indicated that feeding by O. hibisci in the fifth and sixth instars was significantly (P < 0.05) reduced when larvae were parasitized by E. limitarus. Orthosia hibisci in the second through sixth instars in sleeve cages damaged developing apples in the field. Earinus limitarus appears able to reduce O. hibisci numbers for the following year as well as immediate host feeding damage in at least the last two instars.

scholarly journals Insect herbivory facilitates the establishment of an invasive plant pathogen

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Martin M. Gossner ◽  
Ludwig Beenken ◽  
Kirstin Arend ◽  
Dominik Begerow ◽  
Derek Peršoh
Keyword(s):  
Invasive Plant ◽  
Pathogenic Fungus ◽  
Feeding Activity ◽  
Insect Herbivory ◽  
Forest Health ◽  
Mechanical Damage ◽  
Pathogenic Fungi ◽  
Fungal Colonization ◽  
Feeding Damage ◽  
The Impact

AbstractPlants can be severely affected by insect herbivores and phytopathogenic fungi, but interactions between these plant antagonists are poorly understood. We analysed the impact of feeding damage by the abundant herbivore Orchestes fagi on infection rates of beech (Fagus sylvatica) leaves with Petrakia liobae, an invasive plant pathogenic fungus. The fungus was not detected in hibernating beetles, indicating that O. fagi does not serve as vector for P. liobae, at least not between growing seasons. Abundance of the fungus in beech leaves increased with feeding damage of the beetle and this relationship was stronger for sun-exposed than for shaded leaves. A laboratory experiment revealed sun-exposed leaves to have thicker cell walls and to be more resistant to pathogen infection than shaded leaves. Mechanical damage significantly increased frequency and size of necroses in the sun, but not in shade leaves. Our findings indicate that feeding damage of adult beetles provides entry ports for fungal colonization by removal of physical barriers and thus promotes infection success by pathogenic fungi. Feeding activity by larvae probably provides additional nutrient sources or eases access to substrates for the necrotrophic fungus. Our study exemplifies that invasive pathogens may benefit from herbivore activity, which may challenge forest health in light of climate change.

Impact of red squirrel feeding damage on spaced stands of lodgepole pine in the Cariboo Region of British Columbia

1987 ◽  
Vol 17 (7) ◽  
pp. 666-674 ◽  
Author(s):  
Thomas P. Sullivan ◽  
Alan Vyse
Keyword(s):  
British Columbia ◽  
Lodgepole Pine ◽  
Small Diameter ◽  
Red Squirrel ◽  
Feeding Damage ◽  
Animal Damage ◽  
General Decline ◽  
Before And After ◽  
Number Of Stems ◽  
The Impact

This study measured the impact of red squirrel (Tamiasciurushudsonicus Erxleben) feeding damage on spaced stands of lodgepole pine (Pinuscontorta Dougl. var. latifolia Engelm.) in the Cariboo Forest Region of British Columbia. A limited regional assessment of animal damage in spaced stands indicated that squirrels were the most important small mammal damage agents and that lodgepole pine was the only tree species susceptible to squirrel feeding (bark and vascular tissues) injuries. Intensive assessment of damage in two stands showed that squirrel attack was significantly greater among large- (>60 mm dbh) than small-diameter stems. Significantly more spaced than control (unspaced) crop trees were attacked. There was a general decline in the proportion of trees wounded from 1980 to 1985. Some damaged trees grew faster in diameter than undamaged trees of the same size. However, at one study area, damaged trees showed faster radial growth than undamaged trees before and after squirrel attack. Squirrels appear to prefer feeding on vigorous stems and the lost growth of these trees may be substantial. Height growth of damaged trees was significantly reduced in one stand in the years following squirrel damage. Some limit to a tree's capacity to sustain damage, beyond which mortality is inevitable, seems likely. Impact of damage to spaced stands may be minimized by delaying spacing in susceptible areas or by increasing the prescribed number of stems remaining after spacing to compensate for expected mortality and severe damage.

Tourism Development in the South Pacific: The Cases of Nauru and Tuvalu

2019 ◽  
Vol 39 (1) ◽  
Author(s):  
Nick Towner ◽  
Semisi Taumoepeau
Keyword(s):  
Swot Analysis ◽  
Tourism Development ◽  
Geographic Location ◽  
South Pacific ◽  
The South ◽  
South Pacific Ocean ◽  
Economic Survival ◽  
Processing Centre ◽  
Remote Island ◽  
The Impact

Abstract Tuvalu and Nauru are isolated developing island nations located in the South Pacific Ocean. In contrast to the established larger Pacific destinations such as Fiji and Tahiti, the tourism industries on both Tuvalu and Nauru are in their infancy. Tourism development in these remote island nations faces a myriad of challenges which include a lack of infrastructure, environmental susceptibility, economic vulnerability, difficulties with access and considerable distances from major tourist markets. This paper reviews tourism on Tuvalu and Nauru and evaluates their current situation regarding potential tourism development through workshops with relevant stakeholders, surveys and subsequent SWOT analysis. The results of the paper outlined a large number of challenges faced by Tuvalu and Nauru due to their geographic location but also highlighted that both Islands possess fascinating and unique features that have the potential to attract niche tourism markets. A key finding of this paper is that the tourism stimulus or potential attraction can also be the chief threat to the islands’ economic survival hence the two edges of the sword. Further research is required to assess the effect of the withdrawal of the Refugee Processing Centre on Nauru’s economy and to evaluate the impact of climate change on Tuvalu’s society and potential adaption strategies.

Productivity of corn hybrids of different fao groups depending on microfertilizers and growth stimulants under irrigation in the south of Ukraine

2016 ◽  
Vol 3 (1) ◽  
pp. 55-60
Author(s):  
Yu. Lavrynenko ◽  
R. Vozhegova ◽  
O. Hozh
Keyword(s):  
Grain Quality ◽  
Laboratory Method ◽  
The South ◽  
Corn Hybrids ◽  
Early Maturity ◽  
Effi Ciency ◽  
Grain Moisture ◽  
Grain Productivity ◽  
The Impact

The purpose of the research is to identify effi cient microfertilizers and growth stimulants considering biologi- cal features of new corn hybrids of different FAO groups under irrigation conditions in the South of Ukraine and trace their impact on grain productivity of the plants. The methods of the research are the fi eld method – to study the interaction of the research object with experimental factors of the natural environment, to register the yield and evaluate the biometrical indices; the laboratory method – to measure soil moisture, grain moisture content and grain quality indices; the statistical method – to evaluate the reliability of the obtained results; the calculation methods – for economic and energetic assessment of the growing techniques used. The results of the research. The paper defi nes the impact of microfertilizers and growth stimulants on the yield and grain quality of the corn hybrids of different maturity groups and on the economic effi ciency of growing them. The conclusions of the research. Under irrigation conditions of the Southern Steppe of Ukraine it is recommended that the following hybrids should be grown in dark-chestnut soils: early maturity DN Pyvykha, medium-early Skadovskyi, medium maturity Kakhovskyi and medium-late Arabat, using the growth stimulants – treating the seeds with Sezam-Nano and fertilizing with Grainactive at the stage of 7–8 leaves.

Nachhaltigkeit im Wald – vor und hinter der Welle der Globalisierung | Sustainable Forest Management – In Front and Behind the Wave of Globalization

2000 ◽  
Vol 151 (12) ◽  
pp. 502-507
Author(s):  
Christian Küchli
Keyword(s):  
Forest Management ◽  
Cultural Landscape ◽  
Sustainable Forest Management ◽  
Essential Element ◽  
Specific Situation ◽  
The South ◽  
The North ◽  
Time Space ◽  
Starting Point ◽  
The Impact

Are there any common patterns in the transition processes from traditional and more or less sustainable forest management to exploitative use, which can regularly be observed both in central Europe and in the countries of the South (e.g. India or Indonesia)? Attempts were made with a time-space-model to typify those force fields, in which traditional sustainable forest management is undermined and is then transformed into a modern type of sustainable forest management. Although it is unlikely that the history of the North will become the future of the South, the glimpse into the northern past offers a useful starting point for the understanding of the current situation in the South, which in turn could stimulate the debate on development. For instance, the patterns which stand behind the conflicts on forest use in the Himalayas are very similar to the conflicts in the Alps. In the same way, the impact of socio-economic changes on the environment – key word ‹globalisation› – is often much the same. To recognize comparable patterns can be very valuable because it can act as a stimulant for the search of political, legal and technical solutions adapted to a specific situation. For the global community the realization of the way political-economic alliances work at the head of the ‹globalisationwave›can only signify to carry on trying to find a common language and understanding at the negotiation tables. On the lee side of the destructive breaker it is necessary to conserve and care for what survived. As it was the case in Switzerland these forest islands could once become the germination points for the genesis of a cultural landscape, where close-to-nature managed forests will constitute an essential element.

The Impact of Plant Protection Systems on the Productivity of Soybean Varieties under Irrigated Conditions

2019 ◽  
pp. 109-117
Keyword(s):  
Plant Protection ◽  
Crop Protection ◽  
Production Costs ◽  
Protection System ◽  
Average Weight ◽  
The South ◽  
Biological Origin ◽  
Chemical Protection ◽  
Protection Systems ◽  
The Impact

The application of preparations of biological origin in the protection system of soybean grown under conditions of intensive irrigated crop rotations conforms to the modern tendencies of science and production development. The use of them contributes to solving ecological, production and social-economic problems. The study presents the three-year research on the efficiency of systems protecting soybean from pests and diseases based on biological and chemical preparations. The research was conducted in typical soil and climate conditions of the South of Ukraine. Zonal agricultural methods and generally accepted research methodology were used. The purpose of the research was to create a soybean protection system based on preparations of biological origin, ensuring high productivity of high-quality products reducing a negative impact of the crop production on the environment. The study emphasizes that, under irrigated conditions of the South of Ukraine, the application of biological preparations has a positive impact on the indexes of growth, development and formation of the elements of soybean yield structure. There was an increase in the crop biological weight by 13.8 % and 22.1 % and the number of seeds per plant rose by 11.6 and 14.6 % as a consequence of eliminating harmful organisms with the plant protection systems. The larger ground mass was formed by medium-ripe varieties Danai and Svyatogor, on which the increase from protection measures was higher. Weight 1000 pcs. the seeds did not undergo significant changes. It is established that the larger seeds were formed by Danaya and Svyatogor varieties, in which the average weight is 1000 pcs. seeds were 142 and 136 g, respectively, while in the variety Diona this figure was 133 g. There was an increase in the height of the lowest pod when the total plant height rose. For medium-ripe varieties was characterized by a higher attachment of beans, where the highest values of this indicator acquired in the variety Svyatogor. The medium maturing soybean variety Danaia formed the maximum yield of 3.23 and 3.35 t/ha respectively, when biological and chemical protection systems were applied. The research establishes that the application of the bio-fungicide Psevdobakterin 2 (2.0 l/ha) in the crop protection system at the beginning of soybean flowering and the bio-fungicide Baktofit (2.5 l/ha) with the bio-insecticide Lepidotsid-BTU (10.0 l/ha) at the beginning of pod formation does not reduce the productivity of the soybean varieties under study considerably, when compared to the application of chemical preparations. The research determines that the soybean protection system under study ensures a decrease in the coefficient of soybean water uptake by 7.2-13.0 %, increasing the total water intake to an inconsiderable degree. Biologization of the soybean crop protection system leads to a reduction in production costs compared to the chemical protection system. Taking into account the needs for the collection of additional products, costs increase by an average of 1 thousand UAH/ha, while for chemical protection systems by 1.8 thousand UAH/ha. At the same time, the cost is reduced by 220-360 UAH/t and the profitability of growing crops is increased by 3.8-7.8 %. There has been a reduction in the burden of pesticides on the environment and the production of cleaner products. This indicates the prospect of using the biofungicides Pseudobacterin 2 and Bactophyte and the bioinsecticide Lepidocid-BTU on soybeans to protect plants from pests.

The impact of climate temperature on counts, recovery, and death rates due to SARS-CoV-2 in South Africa. (Preprint)

2020 ◽  
Author(s):  
Neven Chetty ◽  
Bamise Adeleye ◽  
Abiola Olawale Ilori
Keyword(s):  
South Africa ◽  
South African ◽  
Death Rate ◽  
Western Cape ◽  
Warm Climate ◽  
The South ◽  
Recovery Rates ◽  
Death Rates ◽  
Online Resource ◽  
The Impact

BACKGROUND The impact of climate temperature on the counts (number of positive COVID-19 cases reported), recovery, and death rates of COVID-19 cases in South Africa's nine provinces was investigated. The data for confirmed cases of COVID-19 were collected for March 25 and June 30, 2020 (14 weeks) from South Africa's Government COVID-19 online resource, while the daily provincial climate temperatures were collected from the website of the South African Weather Service. Our result indicates that a higher or lower climate temperature does not prevent or delay the spread and death rates but shows significant positive impacts on the recovery rates of COVID-19 patients. Thus, it indicates that the climate temperature is unlikely to impose a strict limit on the spread of COVID-19. There is no correlation between the cases and death rates, an indicator that no particular temperature range is closely associated with a faster or slower death rate of COVID-19 patients. As evidence from our study, a warm climate temperature can only increase the recovery rate of COVID-19 patients, ultimately impacting the death and active case rates and freeing up resources quicker to enable health facilities to deal with those patients' climbing rates who need treatment. OBJECTIVE This study aims to investigate the impact of climate temperature variation on the counts, recovery, and death rates of COVID-19 cases in all South Africa's provinces. The findings were compared with those of countries with comparable climate temperature values. METHODS The data for confirmed cases of COVID-19 were collected for March 25 and June 30 (14 weeks) for South African provinces, including daily counts, death, and recovery rates. The dates were grouped into two, wherein weeks 1-5 represent the periods of total lockdown to contain the spread of COVID-19 in South Africa. Weeks 6-14 are periods where the lockdown was eased to various levels 4 and 3. The daily information of COVID-19 count, death, and recovery was obtained from South Africa's Government COVID-19 online resource (https://sacoronavirus.co.za). Daily provincial climate temperatures were collected from the website of the South African Weather Service (https://www.weathersa.co.za). The provinces of South Africa are Eastern Cape, Western Cape, Northern Cape, Limpopo, Northwest, Mpumalanga, Free State, KwaZulu-Natal, Western Cape, and Gauteng. Weekly consideration was given to the daily climate temperature (average minimum and maximum). The recorded values were considered, respectively, to be in the ratio of death-to-count (D/C) and recovery-to-count (R/C). Descriptive statistics were performed for all the data collected for this study. The analyses were performed using the Person’s bivariate correlation to analyze the association between climate temperature, death-to-count, and recovery-to-count ratios of COVID-19. RESULTS The results showed that higher climate temperatures aren't essential to avoid the COVID-19 from being spread. The present results conform to the reports that suggested that COVID-19 is unlike the seasonal flu, which does dissipate as the climate temperature rises [17]. Accordingly, the ratio of counts and death-to-count cannot be concluded to be influenced by variations in the climate temperatures within the study areas. CONCLUSIONS The study investigates the impact of climate temperature on the counts, recovery, and death rates of COVID-19 cases in all South Africa's provinces. The findings were compared with those of countries with comparable climate temperatures as South Africa. Our result indicates that a higher or lower climate temperature does not prevent or delay the spread and death rates but shows significant positive impacts on the recovery rates of COVID-19 patients. Warm climate temperatures seem not to restrict the spread of the COVID-19 as the count rate was substantial at every climate temperatures. Thus, it indicates that the climate temperature is unlikely to impose a strict limit on the spread of COVID-19. There is no correlation between the cases and death rates, an indicator that there is no particular temperature range of the climatic conditions closely associated with a faster or slower death rate of COVID-19 patients. However, other shortcomings in this study's process should not be ignored. Some other factors may have contributed to recovery rates, such as the South African government's timely intervention to announce a national lockout at the early stage of the outbreak, the availability of intensive medical care, and social distancing effects. Nevertheless, this study shows that a warm climate temperature can only help COVID-19 patients recover more quickly, thereby having huge impacts on the death and active case rates.

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