Research regarding the epidemic evolution of Cercospora leaf spot (Cercospora beticola sacc.) under Ezăreni farm conditions

Cercospora leaf spot caused by Cercospora beticola Sacc.is the most destructive disease of sugar beet. Disease varies from year to year, depending on weather conditions, at economic losses is contributing the cultivated cultivar, the moment of infection, effectiveness of control disease, harvesting age also the presence of abiotic stress factors or other diseases. Analysis of this pathogen attack depending on climatic conditions and in terms of no- treatments is concluded with useful results regarding forecasting and warning of treatments against this pathogen in order to obtain high and stable sugar beet crops. This experience was conducted for two years, at the experimental field from Ezareni Farm. Observations focused on the timing of the onset and epidemic evolution occurring Cercospora beticola Sacc. fungus, under natural conditions of infection also on the knowledge of the behavior of the five sugar beet cultivars (Brasov, Barsa, Libero, Merak and Victor) to the attack of the pathogen, depending on climatic conditions. Analyzing the evolution of Cercospora beticola Sacc attack., under the studied cultivars was observed that they showed different levels of resistance to fungus attack. Also in this paper presents results regarding the roots production of studied cultivars. The analyze of the sugar beet root production and their average production reveals an differential behavior of the studied cultivars, due to the climatic conditions that were favored the attack Cercospora beticola Sacc

Epidemic evolution of Cercosppora leaf spot (Cercospora beticola Sacc.) under Ezăreni farm conditions

This study presents the evolution of Leaf spot caused by Cercospora beticola on sugar beet plants (Beta vulgaris L.) cultivated on Ezareni Farm conditions from U.S.A.M.V. ”Ion Ionescu de la Brad”, Iasi. Infections caused by this pathogen occurs each year with a different intensity mainly dependent on climatic conditions, at this losses are contributing: the variety cultivated, the moment of infection, harvesting age, also presence of abiotic stress factors or other diseases. The study of this pathogen was due to the fact that, the differences between cultures treated properly and those inadequately (by reducing the number of treatments, optimal timing of intervention failure, wrong application of plant protection products etc.). This differences are often 10-15% higher compared with estimated production and for untreated cultures reach values of 30-35% [Cioni, F., Maines, G., 2010]. The experience were conducted during 2009, at the experimental field from Ezăreni Farm. The biological material for study consisted in five sugar beet varieties and hybrids and the settlement of cultivar were based on block method, in three repetitions. Studied varieties showed different levels of resistance to the fungus Cercospora beticola Sacc attack. Observations and determinations consisted in a frequent register of the pathogen Cercospora beticola Sacc. on sugar beet leaves, aiming the frequency (F%), intensity (I%) and degree of attack (GA%). As criteria for assessing this pathogen attack level was used a scale with six classes of intensity attack, corresponding to intervals of intensity attack percentage (Rafaila, C., 1980)

Detection of grapevine fan-leaf virus in some grapevine varieties using ELISA test

Grapevine fanleaf virus (GFLV) is responsible for fanleaf degeneration, which is one of the most severe virus diseases of grapevines worldwide. GFLV causes substantial crop losses, reduces fruit quality and shortens the longevity of grapevines in the vineyard. GFLV is transmitted specifically from grapevine to grapevine by the ectoparasitic nematode Xiphinema index, and belongs to the genus Nepovirus in the family Comoviridae. ELISA (with DAS-, TAS- and DASbiotin variants) is the most used method both for diagnosis and studies regarding the sampling strategy for different viruses (detection of the most reliable source of antigen and period of the year in which the analyze is performed). A survey was made to evaluate the sanitary status of grapevine in the ampelographic collection of USAMV Iasi, with regard to occurence of economically important viruses. Propagation material of 36 grapevine varieties was tested for presence of Grapevine fan-leaf virus. In the first test, from 14 varieties of grapevine analized, 8 were found to be infected with GFLV. The second test was performed on 22 vines varieties, 7 showed extinction values that exceed the blank value

Diversity of microbial communities in the phyllosphere of ornamental plants

Researches were carried out on three species of ornamental plants, Chrysanthemum indicum L. (commonly known as Indian chrysanthemum), Alstroemeria aurantiaca L. (commonly known as Peruvian lily or lily of the Incas) and Pelargonium peltatum L. (common names include ivy-leaf geranium or cascading geranium) cultivated in the greenhouse and also, on the experimental fields of USAMV Iasi. Anatomical and physiological characters of leaf surface and their physic-chemical environments substantially influence the density and diversity of phyllosphereinhabiting microorganisms, which may include natural antagonists of important pathogens. The main objectives of this investigation were to study the phyllosphere microbial diversity from both environment (inside and outside) and to quantify the phyllosphere (i.e. leaf surface) microbial population from the ornamental plants. Also, fungal genera were identified for a better understanding of the influence of UV radiation, fluctuating temperature, nutrient resources and relative humidity on fungal diversity from both, inside and outside cultivated species

Occurance of airborne fungal spores with potential allergogen effect in urban and rural educational institutions from Iaşi county, Romania

Air contamination by airborne fungal spores in five educational institutions placed in urban and rural locations of Iasi county, Romania was investigated in 2014 over a period of 3 months (April-June) using the Petri plate gravitational settling (passive) method. Petri plates contained nutrient media (PDA) in three different compositions (classic, with rose-bengal and with streptomycin) were exposed to room air for a 15-min period face upwards to collect particles settling by gravity. The location differed in habitat characteristics, such as urbanisation level, vegetation and microclimate and these characteristics could affect spore occurrence in indoor air. The identification of the fungi was made according to their microscopic properties and through references. The fungal genera most commonly isolated in all five locations were Penicillium, Cladosporium and Aspergillus (40.5, 26.3 and 23.5% of the total, respectively). Our results showed that fungal spores density in the educational institutions air was within the sanitary level accepted for public buildings, with exception of one classroom from the rural area (Mogoşeşti-Siret), which has potential to develop adverse health effects to the occupants (1196 UFC/m3 air)

The occurrence of microscopic fungi in air samples from different educational institutions from Iaşi, Romania

Contamination of the air by fungi in three educational institutions placed in different location of Iasi City, Romania was investigated in 2013 over a period of 3 months (April-June) using the Petri plate gravitational settling (passive) method. Petri plates contained nutrient media (PDA) in three different compositions (classic, with rose-bengal and with streptomycin) were exposed to room air for a 15-min period face upwards to collect particles settling by gravity. The identification of the fungi was made according to their microscopic properties and through references. The moulds most commonly isolated in all three locations were Penicillium spp, Aspergillus spp and Alternaria spp (58.7, 17.6 and 10.4% of the total, respectively). Our results showed that fungal spores density in the educational institutions air was within the sanitary level accepted for public buildings, with exception of one laboratory for students, which has potential to develop adverse health effects to the occupants

Saprophytic and parasitic fungi on ornamental plants from Moldova area (Romania)

This study presents a mycology note that reflects further research for several years of teaching staff of the Faculty of Agriculture, University of Agricultural Sciences and Veterinary Medicine "Ion Ionescu de la Brad" University conducted on ornamental plants in parks and gardens. Research conducted on ornamental plants led to a ten fungal reports, two of them are new for the country, one fungus is new for Moldova microflora, four are new cited like hosts in Romania, one fungus is cited on a new hosts in Moldova and two are very rare citated in Moldova

The influence of PDA, CMA, TA and V8 culture media on the development of Phytophthora infestans de bary. and Phytophthora parasitica dast.

The aim of the study was to learn the influence of culture media on two species of Phytophthora. The development and colony appearance was observed for ten days and the number of spores for ten weeks. In order to achieve this experiment two species of the genus Phytophthora were used Phytophthora infestans de Bary and Phytophthora parasitica Dast. and four culture media PDA, CMA, V8 and TA. In determining the number of spores, 63.63 cm2 of mycelium were collected from the surface of the culture medium and mixed with 250 ml of sterile water. The containers with sterile water and Phytophthora parasitica Dast. and Phytophthora infestans de Bary., were placed in a refrigerator at a temperature of 7° C, to make sure that zoospores are released. The number of spores per milliliter was determined for each of the fungi using the hemocytometer. The highest values were recorded on the dishes with PDA medium, where after calculating the average of nine dishes the colony registered a rate of growth of approximately 1.47 cm. According to these observations we can conclude that the PDA is the most favorable for the development of the Phytophthora infestans de Bary colony. The highest values of the Phytophthora parasitica Dast colony diameter were observed in the plates with V8, where more than half of the plates have reached the edge of the analyzed Petri plates, thus an average diameter of 8.4 cm was registered in the last day of observation. On the TA plates there was also a high growth rate, the diameter of the colony reaching an average value of 5.5 cm at the end of the 10th day of observation. The PDA provided a slower growth rate of the colony diameter, at the end of the observations the colony only measured 3.94 cm, while CMA media composition has provided conditions for development of the average diameter of only 1.67 cm

Research regarding the pathogen agent Dothistroma septosporum (Dorog.) M. Morelet on Pinus cembra L.

The asexual form of the fungus Mycosphaerella attacks most species of pine trees and produces major damage in the woody nursery. This pathogen has had only seven years after the first infection in Tanzania to reach nurseries in central or eastern Africa. Global losses resulting from epidemics in the world were major. There were losses of 67% to Pinus radiata trees 7-8 years of age in California, total losses of P. ponderosa trees in most eastern states of the United States of America and 40% loss of trees P. flexilis in Montana (Taylor, Schwandt, 1998). Within this paper observations were performed in the laboratory and in the field, determinations were made based on symptoms and morphological characteristics of the fungus. To achieve these observations and measurements samples were taken every ten days for three months from The Botanical Garden of Iaşi, from the species Pinus nigra and Pinus cembra damaged by Dothistroma septosporum

Influence of aquasorb and different soil tillage systems on soil microorganisms in fields cultivated with maize

Aquasorb, a hydrophilic polymer (a salt copolymer polyacrylamide), works in absorption-release water cycles and has the property to increase the water holding capacity of soils for several years. The trial was conducted with maize (Zea mays L.) grown on a 2-3% slope field from the Ezăreni Farm, which belongs to USAMV Iaşi, studying the effects of polymer quantity ha-1 , polymer administration moment and soil tillage systems on soil population. The objectives of this research were to isolate and quantify the existing microbial population in soil (Gram positive bacteria, Gram negative bacteria, micromycetes) establishing their participation ratio, the main fungus genres which activate in soil and their activity level for each variant. The results illustrate the influence of Aquasorb and soil tillage systems on the dinamic of microorganisms population, on the relationship between the main groups (bacteria and fungi), and on the micromycetes spectrum determined in each variant of our experimen