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Hemipteran insect species are increasingly present in areas occupied by plants either productive (agricultural or horticultural) or from natural ecosystems, feeding intensely on their sap. They have a high degree of adaptability, usually migrating from warmer areas to temperate areas, so in recent years there have been more and more host plants, in as diverse areas and growing populations. Through this paper we intend to make an assessment of hemipteran species from 3 spaces with diversified mixed plants (agro-horticultural) in Arad and Timiş County to see the population level, the preference of the host plant and also the natural enemies present identified as potential pest control agents. The results obtained showed the presence of the following categories of hemipteran: aphids, cicadas, stinky bugs and lace bugs. Their population level varied depending on the area analyzed and the range of host plants also differed depending on the species. The most numerous were the aphids, related to the analyzed surface, of course due to their small size, followed by lace bugs (all active in the colonies) and then bedbugs (which are solitary) and cicadas. As for the identified natural enemies, they belonged to the following categories: predatory spiders, ladybugs and parasitic wasps. The level of interaction of spiders and ladybugs was analyzed in the light of a small-scale laboratory study and that of parasitic wasps by the presence of mummies (parasitic aphids) and it was found that all identified categories can fulfill the role of control agent, within varying limits the predominance of pests in an analyzed space. [ABSTRACT FROM AUTHOR]

Small cereals such us wheat, barley, oat, and other grasses are very much influenced when talking about crop production and various pathogens which can infect them during growth stages. Among these pathogens like downy mildew, tan spot, Septoria disease and other fungi also the viruses contribute to the yield decreasing and loses. Barley Yellows Dwarf Virus is well known as a pathogen strong related to its carrier (vector) being distributed and transmitted by a whole range of aphid species. The aim of this paper is to compare the relationship between aphids and the pathosystem BYDV- barley under certain treatments with different active ingredients used to control the virus vector. To achieve that we assessed the symptoms like leaf discoloration (lose of green colour) turning in bright yellow and trough influence on tillering, linked to the treatments applied and dosage used. The trial setup consists in 7 treatment including untreated laid in four replicates using randomised blocks. Three assessments were performed, to establish the aphid population, followed by assessment of leaves presenting symptoms of viral infection. We observe that, in the variants where a high density of Rhopalosiphum padi was present, the symptom like yellowing was better exerted compared to the plots where other aphid species were observed and build the aphid population. [ABSTRACT FROM AUTHOR]

In the last two years, in the peri-urban and urban areas of the city of Timisoara (Romania) numerous small insects have been observed. These have been identified as species of the Tingidae family, the order Hemiptera, more specifically species of Corythucha ciliata (sycamore lace bugs). In the western part of the country, the species has had a less evolution and without entering the attention, until 2017. In the last two years it gradually experienced an increasing evolution, so that in summer and autumn of 2019, the population level of they became so great that they changed their behaviour. Known as a pest of the plane tree (Platanus sp.), it has developed adaptive abilities to other species and is often observed on birch trees (Betula sp.). During the month of August when the temperature was high the insect became aggressive, so that in the 2 locations where the observations were made (private gardens with houses) behavioural deviations were recorded. In detail, individuals had a chaotic flight and an attraction to human skin (people in the locations under observation were stung manifesting mild allergy symptoms). Also frequent in September and October (during the prewintering period) they were observed on other plants (conifers) in association with the predatory spiders, caught in their canvas. The cause of their presence on conifers is not known, but most likely they have withdrawn to house buildings and in plants with foliage more often in search of heat, in order to wintering. Some of them were seen on terraces and houses. It is obvious that with the changes in temperature in recent years produced changes in the biology and behaviour of this species. As such, it is important to constantly monitor insect populations and to find solutions for their management, especially invasive ones, as well as the target species of this work. [ABSTRACT FROM AUTHOR]

One of the most recently reported arthropod species in Europe is the oak lace bug, Corythucha arcuata (Insect Class: Order Hemiptera: Tingidae Family). Through this paper we aimed to highlight the adaptation of the insect on new plant species and the implications it has on it. Our study focused on a species very present in the decorative arrangements of gardens and green spaces, namely the Japanese quince (Chaenomeles spp.). The observations were made between April and October during 2020, in three green spaces and two private gardens in the peripheral areas of Timisoara or in the surrounding localities. Accidentally, the insect was reported on this plant, the previous observations being focused primarily on the species mentioned in the literature, in generally on Quercus sp. That is why we turned our attention to Japanese quince and watched the evolution of populations and damage to these plant species. From the observations of bushes from each space analysed, we found that the species is present in all these, in various population levels. Out of a total of 3230 individuals, most specimens found were adult forms associated with eggs, but also immature forms (larvae and nymphs) were found on plants. The first specimens were reported at the end of May, the maximums were recorded at the beginning of June and the last specimens were found at middle of October. Among the areas under study, shrubs in private gardens were by far the most attacked because the population level was also high. And the distance from the Green Forest, due to the presence of oak (which are favourite plants) was taken into account and, as a conclusion, we can say that in the spaces located less than 1 km from it the number of specimens was higher and farther (over 3 km) the fewer specimens. [ABSTRACT FROM AUTHOR]

The species Halyomorpha halys is an arthropod insect (Arthropoda: Insect: Hemiptera: Pentatomidae) that has recently appeared in various places, disrupting both good plant growth but also human comfort and habitat. Although in Romania it was reported 4-5 years ago, and in the western part (Banat) 2-3 years ago, no obvious damages or invasions in the human habitat were recorded. And this is explainable, because at the beginning of the installation in a new area the population level of sting bugs is low. Through the present work we intend to bring to attention the pre-wintering behavior of this species. The period in which the observations were made included 2 months (September and October) of the current year (2019). The place of these observations was conducted in a private mixed garden in Timis county that includes many species of vegetables, fruit trees, ornamental plants, lawn grass, terrace and house. It is interesting the behavior that these stink bugs have during the autumn period, specifically before hibernation. Analyzing their activity at different times of the day I found that they behave differently, being in a continuous movement. At lower temperatures of the day (below 18-20°C) they were removed to sheltered places (terraces, objects present on terraces, warehouses, under layers of leaves, among stones, etc.). At higher temperatures (over 20°C) during the day, the adult forms migrated to the still green plants and continued to feed. There is a dynamic of their flight during this period expressed by chaotic movements from shady to bright places (where the sun is present) and vice versa when the temperatures and intensity become unbearable for them. Being large insects, they can be easily observed in preferred places. Usually they are extremely active and mobile at temperatures between 20-28°C, when the flight was more intense. The aggression of the attack on the plants differs depending on the presence and variety of the preferred plants and the maintenance of the organs of the plant in a green state. In conclusion, this insect has become in the last year (2019) a big problem both for the plants of culture (agricultural, horticultural), for the ornamental ones but especially for the houses of the people. [ABSTRACT FROM AUTHOR]

Maize has been and continues to occupy a major place, being one of the most cultivated plants in Europe. Romania and, in particular, the western part of the country provides a great deal of corn production. As such, special care should be taken to protect these plants against harmful organisms and especially insects. There are currently some species that affect corn crops, and these include Diabrotica virgifera virgifera Le Conte (western corn rootworm), Ostrinia nubilalis (European corn borer) and Helicoverpa armigera (corn earworm). All three species have one particularity. So, Diabrotica is an invasive species that has a great ability to move and few natural enemies. Ostrinia is hard to fight, and there is no clear strategy at the moment. Helicoverpa is known to be highly resistant to insecticides, as well as the previous species. Taking into account all this, in the present paper we have proposed to evaluate the current state of population density of the above-mentioned insects from 10 different maize hybrids. The corn hybrids tested were selected according to the maturity group and their availability on the market. These were included in different maturity groups, such as semi-early, early and semi-early. The FAO classification included groups 300 and 400. The test site was Nerau in Timis County (western Romania) and the period covered 2 years, 2015 and 2016, respectively. Assessment of the population level of each species has been done specifically, depending on the size of the insect and the possibility of better catching them. Thus, colorful panel traps for the species Coleoptera and box-type traps for butterfly species were used. Traps were placed 3 in each batch following the manufacturer's instructions. In all the experimental lots the three harmful species were present in great dimension but the population level did not differ much from hybrid to hybrid. [ABSTRACT FROM AUTHOR]

Aphids are considered to be the most common and most harmful species of insect attacking the rose. The western area of Romania is favorable for the development of a large number to the generations, regardless of the species of aphids. Reducing the population level of aphids by ladybugs (an inexpensive and environmentally friendly biological method is, in fact, the main objective of this paper). In recent years, the ladybugs populations have increased considerably in the natural environment, which has implicitly led to the reduction of the aphid populations present on the plants. It is known that the main food of the ladybugs is aphids, so the interaction between them has been and remains a permanent subject of research in the field of classical biological combat. Three biotic factors have been implicated in this paper: aphids, ladybugs, and rose. The place of observation was identified in the western area of country (Arad County, Santana village). The observations were made during the years 2016 and 2017 and materialized in weekly readings. The rose varieties studied were Rosa Blue Monday, Queen Elizabeth and Rosa Aida. Rose varieties were selected on the basis of frequency in the area and trade availability. Five plants of each variety were monitored and analyzed. The results showed that on all rose varieties there were both aphids and ladybugs. Aphids were represented by the species Macrosiphum rosae (rose aphid), Myzaphys rosarum (pink aphid of the rose) and the predators (ladybugs) of the invasive species Harmonia axyridis (Asian ladybugs). The Rosa Aida variety was highlighted by a total of 130.75 aphids consumed by predators. Average results were obtained on the Queen Elizabeth variety (21.7 aphid consumed). Low efficiency was recorded in the Rosa Blue Monday variety, where only 8.71 aphids were consumed. The explanation would be that where the aphid's population is large and the population of the predators grows. As a recommendation, exploitation of ladybugs present in crops is encouraged. By naturally controlling biological exploitation of the ladybugs it reduces number of chemical treatments. [ABSTRACT FROM AUTHOR]

In recent years, in the parks and gardens of urban and rural areas in Romania, the harmful species Coreus marginatus (Linnaeus, 1758) has been often observed. After analyzing the information set, we found that there is little information at the national and even international level about the phytophagous character and its host plants. Until recently, the species was not a problem. That's why we proposed that through the present work, we would see the causes that led to the increase in its population. Through our 2-year study, 2021-2022 in 4 places in western Romania, we noticed that the insect is present especially in areas with various plant species in warm springs and summers. From the findings, it is obvious that the species is frequent in great color variability, at a high and very high level/the analyzed plant (n=3; n=6) in the 2 urban localities compared to the rural localities, where it was present at a low and absent level (n= 1.0; n=0.0). The ornamental plants with host potential were identified as follows: Chaenomeles japonica, Rosa l., Lavandula sp., Magnolia liliiflora, Convallaria majalis but also spontaneous plants such as Cirsium arvense. Most specimens were found on Chaenomeles and Rosa, where both adults and nymphs were observed feeding on sap from leaves, stems, inflorescences or seeds from inflorescences. The warm sunny periods of the day are favorable for its activity. We can conclude that the species has harmful potential due to the population growth or widening of the range of host plants, but we suspect that it is also due to the high temperatures in the summer and the places protected from the wind in autumn. [ABSTRACT FROM AUTHOR]

Ladybugs are increasingly present lately in agricultural crops, horticulture, gardens and parks, both in individual and mixed culture systems. The connection between them and plants is less supported because they are present where phytophagous aphids are also present. The role of ladybugs is beneficial, as they are known to reduce the populations of aphids that feed on plants. Bearing these things in mind, we proposed that through the present paper we will see what is the share of native and harlequin (Asian) species, the latter being invasive. It is also important to see what the ratio is between ladybugs and the aphid populations present. The study was carried out for 2 years (2021-2022) in a mixed space that combines various ornamental plants, corn, vegetables and fruit trees, dispersed over 1000 m2, located near the houses. From the ones analyzed, we found that the harlequin ladybugs had a higher percentage than the local ones (ie, 68% compared to 42%). Regarding their association with aphid populations, we found that the predator-phytophagous ratio was 1 ladybug to 20 aphids. This highlights that the populations of aphids in a mixed space that offers the possibility of shelter over the winter and implicitly large populations of ladybugs in the following year, can be managed only by ladybugs, no other control solutions are necessary. [ABSTRACT FROM AUTHOR]

Studies covered the topic of this paper continue work started in 2008 in western part of Romania, actually refers to comparative studies between different localities. This approach is original and is the subject of research project. During 2010, as well as during previous year, the monitoring of Diabrotica virgifera virgifera (WCR) was done continuing the implementation of a usual protocol. For establish of adults number were used Hungarian pheromone traps (Csalomon ® Diabrotica v.v. pane type /2pieces). The traps were installed from June to September, in three repetitions (Trap1, Trap2, Trap3/place). The frequency of Diabrotica virgifera virgifera Le Conte adults was based on readings directly in fields, in 19 localities from 8 counties (Timis, Arad, Hunedoara, Bihor, Cluj, Satu Mare, Salaj, Caras Severin, Alba, Mures) situated in western part of Romania. For installing of traps we used the common methods and for finding the location the GPS was used. The researches were made in conventionally maize, untreated against target pest. The movement to experimental fields was made used the car from Entomology and Zoology Agricultural of BUASVMT. The air temperature, soil temperature, relative humidity and moisture constituted ecological factors from basis of correlations between adults' number and climatic conditions from different altitudes. The data were taken from Weather Stations associated each county studied. From analyzing the data obtained (averages of adults captures) in accordance with climatic factors apparent significance differences. After analyzing correlations with climatic factors reveals positive correlations compared with air temperature (r=0,324, r=0,005) soil temperature (r=0,373, p=0,015) and negative correlations compared with humidity (r=0,279, p=0,015). In conclusion, registered values of adults captured increase when humidity is low and high temperature or decrease if the humidity increases and temperature decreases. We acknowledge the Ministery Education financed this work within the framework of PN-II-ID-PCE-2007-1/RO project and Weather Stations from each county taken in study. [ABSTRACT FROM AUTHOR]

Accidentally, in the last year (2010), during monitoring activities by reading of traps installed in maize fields, on other plants than maize were observed numerous individuals adults of Diabrotica virgifera v. Le Conte in a process of intense feeding on leaves and flowers. The researches carried out in western part of Romania, in a small plot of maize grown (in stage silk appeared) in combination with beans and pumpkin (this kind of plots are common). Special attention was drawn to the fact that although there is pheromone traps on maize plant the adult preferred beans leaves and flowers. The studies about the preferences of adult Diabrotica virgifera virgifera Le Conte on different type of host plants was observed in field condition, in cages of isolation. Following the results of these primary data we mention that is important to emphasize attractiveness of Diabrotica virgiferea virgifera Le Conte adults for other plants than maize plants. Is clearly evident the preference of adults for pumpkin (mean of 38.5 individuals/RI, RII, RIII, RIV), followed by maize (32.0 individuals/ RI, RII, RIII, RIV) and beans (29.5 individuals/ RI, RII, RIII, RIV). The number of adults feeding on the flowers, pollen or silk in isolation cage was assigned higher (54 adults/maize, 48 adults/pumpkin and 46 adults/bean) than number of adults feeding on the leaves (14 adults/beans, 12 adults/pumpkin and 6 adults/maize). Taking into consideration the sex ratio, the number of males and females varied from host plant to host plant. After our observations and information from literature regarding other species of genus Diabrotica, we conclude that adults of Diabrotica virgifera virgifera Le Conte could turn to other crops than corn for feeding but also for egg laying. If is happened in natural conditions of beans crop or other potentially host plant then we have to take protection measures by introduction of appropriate crop rotation. Activities were carried out under financially support of the PN-II-ID-PCE- 2007-1/RO project. [ABSTRACT FROM AUTHOR]

The pathogen Coccomyces hiemalis Higg. causes big losses in nursery gardens, generating massive defoliations. The fungus causing this disease produces infections in the spring, during flowering and during petal falling, by generating a mycelium that has several infection cycles in the vegetation stage, with 7-9-day incubation period, if the mean temperature is 17.6- 21.8deg;C. The leaves attacked fade under conditions of premature defoliation and shoots and twigs die down, at the beginning of autumn. To determine the attack caused by Coccomyces hiemalis Higg. that produces cherry tree anthracnose, the main disease affecting this tree species, we carried out observations on a number of 8 cherry tree varieties and determined attack's risk degree, frequency and intensity during the maximal attack period. We have done research on the influence of varieties, shapes and distance crown planting trees on the main diseases and pests attack. The fungus forms completed in the conditions of the area, with a high degree of sporulare being pretentious to temperature (biological threshold 10°C)and humidity. Terms of disease evolution were fired since April when he made ascosporilor design. Varieties' resistance was determined according to the results obtained; then we determined the warning and the application of phyto-sanitary treatments. From the viewpoint of the attack caused by Coccomyces hiemalis Higg., in the South-West of the country, we grouped the cherry tree varieties as follows: slightly attacked (SA: Seneca, Cerna, Ulster); medium attacked (MA: Timpurii de Mai, Rosii de Bistrita); strongly attacked (PA: Van, Bing, Germesdorf). To reduce the environmental pollution occurred during the chemical control of this disease, we recommend the introduction of slightly- and medium- attacked varieties in cherry tree orchards. Compared with the number of 8 phyto-sanitary treatments warned, we applied only 4 treatments, in the slightly attacked varieties: Seneca, Cerna, Ulster; this represents a 50% reduction of treatments and environmental pollution. [ABSTRACT FROM AUTHOR]