George Vlontzos

Using a Lethality Index to Assess Susceptibility of Tribolium confusum and Oryzaephilus surinamensis to Insecticides

We evaluated knockdown caused by four insecticides: alpha-cypermethrin, chlorfenapyr, pirimiphos-methyl and fipronil against adults of Tribolium confusum Jacquelin Duval, the confused flour beetle and Oryzaephilus surinamensis (L.), the sawtoothed grain beetle. Bioassays were conducted on concrete and metal surfaces. Adults of the tested species were exposed on both surfaces treated with the above insecticides at two doses (low and high). Knockdown assessment was done after 15, 30 and 60 min of adult exposure in the treated surfaces. Also, after 1, 3, 5, 7 and 14 d of exposure, a lethality index was calculated with an equation resulting to values from 0 to 100, where 100 indicated complete mortality and 0 complete survival. We also developed a lethality index by ranking each adult on each surface from 0 to 4, 0: adults moved normally, 1: adults were knocked down, but were able to walk for short intervals, 2: adults were knocked down and unable to walk, but with visible movement of antennae etc., 3: adults were knocked down, with very minimal movement of the tarsi and the antennae and 4: adults were dead (no movement). Knockdown of adults immediately after exposure (15–60 min) was higher for pirimiphos-methyl followed by alpha-cypermethrin, for both dose rates tested and species, but only on the metal surface. The lethality index was nearly 100 for all insecticides after 5d of exposure for O. surinamensis, while for T. confusum the adult lethality index was considerably lower for alpha-cypermethrin, suggesting that that recovery from knockdown occurred. Chlorfenapyr was the only insecticide that was more effective on concrete than on metal, while the reverse was noted for the other three insecticides. These results show that knockdown has different levels, which can be used as indicators of insect mortality or recovery.

The impact of the Greek crisis on the consumers’ behaviour: some initial evidences?

Purpose – The purpose of this paper is to examine the changes on food consumption patterns of households, due to the ongoing economic crisis in Greece. Design/methodology/approach – A sample survey among a random sample of 932 households living in the region of Thessaly, central Greece, was carried out, with the consuming behaviour to be focused on 20 basic food products. An exploratory factor analysis, followed by a hierarchical classification of the households, was implemented. Findings – Six patterns of food consumptions behaviour have been detected, revealing that most of the households have modified their eating habits, by reducing the quantities consumed and/or looking for less expensive brands. Only 15 per cent of the households do not seem to be affected by the crisis and the austerity policy. The spatial dimension of the research signify that low-income households in urban areas, where the majority of the population lives, are deeply affected by the crisis, with these percentages to be even high...

Investigation of the relative efficiency of LEADER+ in rural areas of Northern Greece

The aim of this paper is to investigate and measure the relative efficiency of LEADER+ action plans of seven rural areas in Northern Greece. To this end, a Data Envelopment Analysis (DEA) model is used, which is based on data from LEADER+ provided by the Ministry of Agriculture. In particular, the DEA method is used for measuring the relative efficiency of local actions and for the investigation of the inputs and outputs and to show how the maximisation of their relative efficiencies could be achieved through its use. The specific DEA model has the required characteristics for the empirical application of the input-oriented DEA method. The model shows that some Decision-Making Units could maximise their relative efficiency by proceeding to internal adjustments of the inputs being used, and it is these internal adjustments which are being taken into consideration for this paper.

Measuring efficiency of the Greek flourmill firms using data envelopment analysis

The objective of this paper is to measure the efficiency of Greek flourmills firms, using the DEA methodology. The CRS and the VRS technical efficiency is measured as well as a return to scale estimation, the context dependent DEA is calculated and finally, the evolution of the Malmquist productivity index, the efficiency change and the frontier shift was computed for a five-year period. This implementation provided helpful information regarding the efficiency ranking of the firms operating in it. Proofs that inefficient firms are over-invested and over-exposed to high risk operation practices provide suggestions for future reparative actions in order for efficiency to be improved. This goal does not require radical effort from firms to achieve intermediate targets. Finally, stagnated mean efficiency change does not denote stagnated efficiency change for individual firms, but it is the outcome of a large variance of efficiency change scores being achieved by flour mills firms from period to period. This is the first attempt to assess the level of competitiveness and benchmark the firms operating in the Greek flourmill industry.

The Greek olive oil market and the factors affecting it

The objective of the research was to highlight the role that socio-economic and spatial attributes of consumers – households exert on their choices regarding not only the supply modes but also the price they are willing to pay for different categories of olive oil, especially the packaged one. Three aspects are successively examined as regards alternative characteristics of olive oil that are proposed: (a) the label, (b) the quality certification protocol and finally (c) the respect of environmental criteria in the production process. It verifies that significant market shares belong to informal networks, which are analyzed to self-consumption, and purchase from either relatives or friends who produce it. The most influential factors purchasing olive oil, amongst others being examined, are the age, the educational level, and the placement of residents in olive oil producing zones. Regarding the wtp for different olive oil labels, consumers are willing to pay premiums only for olive oils being processed by either private companies or cooperatives, with the latter to gain 34% of them in the case they would decide to change the olive oil they usually purchase. The most important consumer profiles are that young educated consumers turn to buy olive oil from sm, do not want to pay less for sm own label olive oil, and they perceive olive oil being packaged by cooperatives as a distinct product they want to use, and pay a premium for it. On the contrary, elderly people are willing to pay less for own label olive oil.

What Are the Main Drivers of Young Consumers Purchasing Traditional Food Products? European Field Research

In this research, the attitude of European young adults (age 18 to 30 years) regarding their consumption of local and traditional products was examined. The survey was conducted on a sample of 836 consumers from seven European countries (Greece, Bulgaria, Romania, Slovenia, Croatia, Denmark and France). Data collection was made by distributing a developed questionnaire through social media and university mail services. Principal Component Analysis (PCA) was used to identify consumer perception comparing the overall sample with two subsets (consumers from Eastern and Western European countries). Six major factors were revealed: consumer behavior, uncertainty about health issues, cost, influence of media and friends and availability in store. Young adults had a positive attitude to local and traditional food products, but they expressed insecurity about health issues. Cost factor had less of an influence on interviewees from Eastern European countries than those from the overall sample (3rd and 5th factor accordingly). Influence of close environment was a different factor in Eastern countries compared to Western ones, for which it was common to see an influence from media. Females and older people (25–30 years old) have fewer doubts about Traditional Food Products, while media have a high influence on consumers’ decisions. The aim of this survey was to identify the consumer profiles of young adults and create different promotion strategies of local and traditional products among the two groups of countries.

Data mining and optimisation issues in the food industry

Data mining applications in the food industry has until now expressed in many ways, on both technical and economic terms. The most important methodologies being used are clustering, classification, feature selection and outlier detection. The techniques commonly used in data mining are artificial neural networks, decision trees, k-means type algorithms, genetic algorithms, nearest neighbour method, and rule induction. Successful case studies of the implementation of these methodologies are fruit and vegetable classification, with special focus on apples, citrus, strawberries, table olives, onions etc. the same rationale is being followed for the evaluation of processed foodstuff. Efficient solutions have been provided for wine classification, based on organoleptic characteristics, fish and meat classification, as well as robotic harvesting. Finally, applications on supply chain management and e-commerce have provided significant solutions on issues of monitoring and evaluation of dynamically changing datasets.

Evaluating consumer beliefs for traditional and localised foodstuff under economic stress

The aim of this paper is to examine the changes on food consumption patterns of households, following an economic crisis and recession. This paper identifies objective and subjective factors influencing consumers to purchase, or not, traditional and localised food. Furthermore, an impact assessment based on environmental and social criteria for food selection, like locality of production and healthy nutrition habits is conducted. Quite enlightening is the research on the spatial basis. The results of this approach signify the different consumption trends dominating the urban, semi-urban, and rural areas. There are also some implications for marketing and public policy makers to further strengthen consumption of traditional and locally produced foodstuffs, such as promotion of their nutritional characteristics, support of local economies, encouragement for adoption of healthy eating by children, as well as enjoyment of cooking.