Estimating Trends of Population Decline in Long-Lived Marine Species in the Mediterranean Sea Based on Fishers' Perceptions

We conducted interviews of a representative sample of 106 retired fishers in Italy, Spain and Greece, asking specific questions about the trends they perceived in dolphin and shark abundances between 1940 and 1999 (in three 20 year periods) compared to the present abundance. The large marine fauna studied were not target species of the commercial fleet segment interviewed (trawl fishery). The fishers were asked to rank the perceived abundance in each period into qualitative ordinal classes based on two indicators: frequency of sightings and frequency of catches (incidental or intentional) of each taxonomic group. The statistical analysis of the survey results showed that both incidental catches and the sighting frequency of dolphins have decreased significantly over the 60+ years of the study period (except for in Greece due to the recent population increase). This shows that fishers' perceptions are in agreement with the declining population trends detected by scientists. Shark catches were also perceived to have diminished since the early 1940s for all species. Other long-lived Mediterranean marine fauna (monk seals, whales) were at very low levels in the second half of the 20th century and no quantitative data could be obtained. Our study supports the results obtained in the Mediterranean and other seas that show the rapid disappearance (over a few decades) of marine fauna. We show that appropriately designed questionnaires help provide a picture of animal abundance in the past through the valuable perceptions of fishers. This information can be used to complement scientific sources or in some cases be taken as the only information source for establishing population trends in the abundance of sensitive species

Managing Herbicide Resistance: The Role of Extension

The rapid evolution of herbicide resistance poses a significant threat for conventional agricultural practices. In practice, herbicide resistance seems to be a very complicated problem to deal with. Extension can play a significant role in managing herbicide resistance educating farmers on the main advantages and disadvantages of the available methods aiming to control and minimize herbicide resistance. This could be achieved by redirecting the educational efforts more towards the principles of weed biology and integrated weed management, teaching farmers how to learn, paying attention to the basic prerequisites for the new control methods and providing precise information about the economic usefulness of each proposed method

Current Status and Recent Developments in Biopesticide Use

Biopesticides have attracted attention in pest management in recent decades, and have long been promoted as prospective alternatives to synthetic pesticides. Biopesticides have also attracted great interest in the international research community, with a significant increase in the number of publications devoted to the subject. Recently, new substances, like strains of the fungus Talaromyces flavus SAY-Y-94-01, extracts of the plant Clitoria ternatea (butterfly pea), products of the fungus Trichoderma harzianum, products of the bacterium Bacillus thuringiensis var. tenebrionis strain Xd3 (Btt-Xd3), the alkaloid compound oxymatrine, fermentation products of the bacterium Lactobacillus casei strain LPT-111, stilbenes accumulated in grape canes, and olive mill wastes, have been reported in the literature as promising compounds for use as biopesticides, but more field research is required to assess the effects on specific pest problems under diverse cropping systems. Nevertheless, biopesticides have not yet reached the desired level of use, whereby they could displace the dominance of chemical pesticides, given that the commercialization of new products in the market is lagging behind. Currently, biopesticides comprise a small share of the total crop protection market globally, with a value of about $3 billion worldwide, accounting for just 5% of the total crop protection market. Fewer biopesticide-active substances are registered in the European Union (EU) than in the United States, India, Brazil, or China, due to long and complex registration processes in the EU, which follow the model for the registration of conventional pesticides. Nanoformulations and microencapsulation technologies can improve the stability and residual action of biopesticide products, and this could increase their field use. Regulations that promote registration of low-risk compounds with the provision of incentives could also facilitate commercialization and availability of biopesticides in the market

Pesticide Exposure, Safety Issues, and Risk Assessment Indicators

Pesticides are widely used in agricultural production to prevent or control pests, diseases, weeds, and other plant pathogens in an effort to reduce or eliminate yield losses and maintain high product quality. Although pesticides are developed through very strict regulation processes to function with reasonable certainty and minimal impact on human health and the environment, serious concerns have been raised about health risks resulting from occupational exposure and from residues in food and drinking water. Occupational exposure to pesticides often occurs in the case of agricultural workers in open fields and greenhouses, workers in the pesticide industry, and exterminators of house pests. Exposure of the general population to pesticides occurs primarily through eating food and drinking water contaminated with pesticide residues, whereas substantial exposure can also occur in or around the home. Regarding the adverse effects on the environment (water, soil and air contamination from leaching, runoff, and spray drift, as well as the detrimental effects on wildlife, fish, plants, and other non-target organisms), many of these effects depend on the toxicity of the pesticide, the measures taken during its application, the dosage applied, the adsorption on soil colloids, the weather conditions prevailing after application, and how long the pesticide persists in the environment. Therefore, the risk assessment of the impact of pesticides either on human health or on the environment is not an easy and particularly accurate process because of differences in the periods and levels of exposure, the types of pesticides used (regarding toxicity and persistence), and the environmental characteristics of the areas where pesticides are usually applied. Also, the number of the criteria used and the method of their implementation to assess the adverse effects of pesticides on human health could affect risk assessment and would possibly affect the characterization of the already approved pesticides and the approval of the new compounds in the near future. Thus, new tools or techniques with greater reliability than those already existing are needed to predict the potential hazards of pesticides and thus contribute to reduction of the adverse effects on human health and the environment. On the other hand, the implementation of alternative cropping systems that are less dependent on pesticides, the development of new pesticides with novel modes of action and improved safety profiles, and the improvement of the already used pesticide formulations towards safer formulations (e.g., microcapsule suspensions) could reduce the adverse effects of farming and particularly the toxic effects of pesticides. In addition, the use of appropriate and well-maintained spraying equipment along with taking all precautions that are required in all stages of pesticide handling could minimize human exposure to pesticides and their potential adverse effects on the environment

Environmental Impact of Peanut (Arachis hypogaea L.) Production under Different Levels of Nitrogen Fertilization

A field experiment was conducted in Astaneh-ye Ashrafieh of Guilan Province in northern Iran to evaluate the environmental impact of peanut (Arachis hypogaea L.) production under three levels of nitrogen (N) use (0, 30, and 60 kg ha−1) applied in the form of urea fertilizer. Six categories of environmental impact (i.e., global warming potential, acidification potential, terrestrial eutrophication potential, depletion of fossil resources, potassium resources, and phosphate resources) were determined. The functional unit was assumed the production of one ton of peanut pod yield. Peanut pod yield increased by 48.8% with N rate 30 kg ha−1 and by 108.6% with N rate 60 kg ha−1, compared with control (without N fertilization). The environmental index (EcoX) values with regard to global warming, acidification, and terrestrial eutrophication potential were 0.18, 0.52, and 0.66 for N rates of 0, 30, and 60 kg ha−1, respectively. Increase in N rate aggravated the emission of NH3 and N2O, resulting in more harmful effect of peanut growth on the environment at higher N rates than control (without N fertilization). The resources depletion index (RDI) values with regard to depletion of fossil resources, potassium resources, and phosphate resources were 0.80, 0.53, and 0.30 for N rates of 0, 30, and 60 kg ha−1, respectively. Increase in N rate and the resultant higher peanut yield mitigated the environmental effects of fertilization mainly by reducing the depletion of phosphate resources. Proper N input is a major consideration for mitigating environmental impacts of N fertilization in crop production and producers should be informed to use the least rate that will give them an economic optimum return over the long run

Farmers’ Training on Pesticide Use Is Associated with Elevated Safety Behavior

Occupational exposure to pesticides in agricultural applications may cause acute and long-term health effects to farmers, and thus research on factors that reduce exposure is useful. However, studies on the relevance and effectiveness of training are limited. The association of previous training in the form of intensive seminars relating to pesticide use (e.g., use of spraying equipment, application parameters, use of personal protective equipment, risks to human health and the environment) with farmers’ knowledge and behavior in pesticide use was studied via the self-reporting method in a purposive sample of 82 trained and non-trained farmers. Most trained farmers showed higher levels of knowledge of pesticide use, higher levels of beliefs in pesticide hazard control, and higher levels of safety behavior than non-trained farmers. Knowledge of pesticide use and beliefs regarding pesticide hazard control were significantly correlated with safety behavior in both groups of farmers. Concerning farmers’ beliefs regarding pesticide hazard control, trained farmers were more likely to think that safety precautions work very well and less likely to feel they had little control over avoiding pesticide hazards. Overall, previous training was associated with increased levels of farmers’ knowledge of pesticides and beliefs about pesticide hazard control, was accompanied by elevated safety behavior in farmers, and thus was connected with lower occupational exposure to pesticides. Interventions that facilitate knowledge and compliance with safety behaviors should become a priority for decreasing exposure to pesticides among farmers

Weed Competition Effects on Growth and Yield of Spring-Sown White Lupine

White lupine (Lupinus albus L.) is an annual legume that is grown for both seeds and green biomass, but several agronomic aspects of this crop, including response to weed competition, have not been studied extensively. Field experiments over two growing seasons (2012 and 2016) were carried out in Orestiada, Greece, to study the growth and development of spring-sown white lupine under season-long weed competition from natural weed flora compared with its growth without weed competition. Treatments were arranged in a randomized complete block design with four replications and included (i) a non-treated (weedy) control, where weeds (Chenopodium album and Sorghum halepense) remained in the plots throughout the experiments and (ii) a weed-free control, where weeds were removed upon crop emergence and the plots were kept free of weeds throughout the experiments by hand removal. The presence of Chenopodium album and Sorghum halepense reduced the aboveground dry matter accumulation of white lupine ‘Multitalia’ at 7 weeks after crop emergence by 18.0% in the first growing season and 29.5% in the second growing season, while the corresponding decrease in the aboveground dry matter accumulation at 9 weeks after crop emergence was 25.3 and 33.4%. However, the reduction in dry matter accumulation was limited to lower levels after flowering (9.9% in the first and 12.8% in the second growing season). In both growing seasons, values of the ability to withstand competition (AWC) index were lower at 7 and 9 weeks from crop emergence than at maturity. Seed yields were 1.58 Mg per ha under weedy conditions and 2.20 Mg per ha under weed free conditions in the first growing season, and 1.59 and 2.32 Mg per ha, respectively, in the second growing season. The values of the relative yield loss (RYL) index for seed yield were 28.2% in the first growing season and 31.5% in the second growing season. Overall, white lupine growth and seed yield was significantly affected by the occurrence of weeds mostly at the early vegetative stages, resulting in the potential yield not being achieved due to weed competition. Future research on weed competition across several sites and years would be useful to define more clearly the critical period of weed control in white lupine

Farmers’ Technical Knowledge about Integrated Pest Management (IPM) in Olive Production

While Integrated Pest Management (IPM) is a sustainable approach of pest control, contributing to reduced use of pesticides and risks on human health and the environment, farmers have shown limited interest in practicing this method. The present study explored the levels of technical knowledge about integrated management of the olive fly (Bactrocera oleae) among olive growers in Roudbar County of Iran and factors underpinning olive farmers’ technical knowledge of integrated management. Data were collected in a survey of olive farmers, on the basis of a structured questionnaire. Almost half of the farmers (48.4%) had good to excellent levels of technical knowledge of integrated management, while almost a third of the farmers (35.4%) had a moderate knowledge level. However, a noticeable portion of the farmers (15.9%) had poor knowledge of integrated management. Moreover, most farmers showed average knowledge of the adverse effects of pesticides on human health. While most farmers showed good levels of social participation, cooperation with institutes, and participation in extension activities, they showed low levels of community involvement (involvement in a group of people that have and share common interests with each other). Olive imports and the lack of a common action for olive fly control were perceived as the main barriers of IPM adoption among most farmers. Regression analysis revealed that increased community involvement, large area under olive farming, participation in education activities, and high farming experience promoted farmers’ technical knowledge of integrated olive fly control. Strengthening growers’ technical knowledge of IPM through community involvement and extension services among inexperienced small-scale olive farmers is recommended for reducing possible unnecessary insecticide sprays in olive production