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Papers by Petruta Mihaela Matei

Lucrări Ştiinţifice - Universitatea de Ştiinţe Agronomice şi Medicină Veterinară Bucureşti. Seria B, Horticultură, 2009

Scientific Papers - Series B, Horticulture, 2018

Progress of Cryogenics and Isotopes Separation, 2017

European Journal of Plant Pathology, 2016

The upsurge in fungal diseases that cause grapevine wood rot in young and adult plants remains a ... more The upsurge in fungal diseases that cause grapevine wood rot in young and adult plants remains a major concern for the wine sector. Since pruned vine shoots act as a reservoir of these fungi, there is a need for sanitization methods that can prevent their spread, avoiding plant reinfection. In this work, the effectiveness of dry heat treatments for the disinfection of pruning waste has been investigated. The thermal death of two inocula of Diplodia seriata fungus, associated to black dead arm disease, was studied in vitro at four different temperatures (40, 50, 60 and 65 °C) for different time periods (20, 40, 60, 90, 120 and 150 min) in a dry air incubator. Obtained data confirmed that inhibition increased as a function of temperature and exposure time. First-order and Weibull models were compared to describe D. seriata fungus survival curve kinetics, with high R2 values (0.923 and 0.930, respectively) and high significances (p < 0.001). Both models predict that the time required to reach 99 % mortality at 65 °C would be 143 min, slightly higher than the experimentally determined minimum time of 120 min. The thermal death kinetics data reported herein has direct applications in process design and validation studies of other grapevine-pruning-waste sanitization methodologies.

Handbook of Composites from Renewable Materials

During the last years there have been recorded very hot periods during the summer, deficits of pr... more During the last years there have been recorded very hot periods during the summer, deficits of precipitations, a more reduced growth of the berries, an acceleration of the phenological stages, the harvesting of the grapes being proceeded with up to two weeks. Also, there have been recorded increased accumulations of sugars in the grapes outrunning with 30 g/l the values obtained during normal years. The year 2007, the hottest in the last decade, with a pronounced deficit of precipitations from the interval May-August determined a predominance of a productive activity and high content of sugar (224.1 g/l in Guyot on demi-high trunk, 216.2 g/l in Cazenave cordon and 202.7 g/l in spur-pruned cordon). Pursuant to these changes there have also been recorded differentiated distributions of the dry matter between the various organs of the vines. The climate warming accentuated in the last years has influences positively the quality of grapes allowing the acquirement of high quality wines.

Agronomy

Fusarium culmorum is a soil-borne fungus able to cause Fusarium head blight, one of the most impo... more Fusarium culmorum is a soil-borne fungus able to cause Fusarium head blight, one of the most important cereal diseases worldwide, which can result in significant yield losses of up to 50% and which jeopardizes food and feed safety due to the mycotoxins produced. In the study presented herein, the enhancement of the antifungal activity against this pathogen, resulting from the addition of silver nanoparticles (AgNPs) to different polyphenol-stevioside inclusion compounds, dispersed either in a chitosan oligomers hydroalcoholic solution or in a choline chloride:urea:glycerol deep eutectic solvent, was investigated in vitro. The polyphenols assayed were curcumin, ferulic acid, gallic acid and silymarin. Four composite concentrations (62.5, 125, 250 and 500 µg·mL−1), with and without AgNPs, were assessed, finding noticeable differences in mycelial growth inhibition, with EC50 and EC90 values ranging from 118 to 579 µg·mL−1 and from 333 to 2604 µg·mL−1, respectively. The obtained results...

AgriEngineering

Phytophthora cinnamomi is responsible for radical rot in a wide range of hosts, resulting in larg... more Phytophthora cinnamomi is responsible for radical rot in a wide range of hosts, resulting in large economic and ecological losses worldwide. In Spain, it is responsible for diseases such as the oak decline or the chestnut blight. In this study, different polyphenol-stevioside inclusion compounds dispersed in a hydroalcoholic solution of chitosan oligomers have been investigated, with a view to their application as natural bioactive complexes to replace conventional systemic fungicides against this fungus. The polyphenols tested in vitro were curcumin, ferulic acid, gallic acid and silymarin. Three concentrations (125, 250 and 500 µg·mL−1) were assayed, with and without silver nanoparticles (AgNPs), and notable differences were found in the inhibition of mycelium growth, with EC50 and EC90 values ranging from 171 to 373.6 µg·mL−1, and from 446.2 to 963.7 µg·mL−1, respectively. The results obtained showed that the addition of AgNPs, despite their antimicrobial activity, did not always...

Congreso Ibérico de Agroingeniería

Congreso Ibérico de Agroingeniería

The upsurge in fungal diseases that cause grapevine wood rot in young and adult plants remains a ... more The upsurge in fungal diseases that cause grapevine wood rot in young and adult plants remains a major concern for the wine sector. So as to study the effectiveness of heat treatments for the sanitization of pruning waste, the thermal death of two inocula of Diplodia seriata fungus-associated to black dead arm disease-was studied in vitro at different temperatures in a dry air incubator, confirming that inhibition increased as a function of temperature and exposure time. First-order and Weibull models were compared to describe D. seriata fungus survival curve kinetics, with high R 2 values (0.923 and 0.930, respectively) and high significances (p<0.001) for both models. According to the first-order model, the time required to reach 100% mortality at 65 °C was 120 min (or 93 min to 95%), whereas for the Weibull model a 90% reduction was attained after 73 min.

Antibiotics (Basel, Switzerland), Jan 16, 2018

“Agriculture for Life, Life for Agriculture” Conference Proceedings

Broad scale use of chemical pesticides is known to have produced broad scale environmental impact... more Broad scale use of chemical pesticides is known to have produced broad scale environmental impact worldwide and, at the same time, discovery and registration of new molecules to be used as insecticides, herbicides and fungicides have slowed significantly along the last decades, reducing the number of options for pest control by the farmers. Searches for novel environmentally friendly products are a recognized priority. In this work, aqueous solutions of chitosan oligomers (COs) and propolis (P), individually or as binary mixtures, were tested against Hemileia vastatrix, the fungus which causes coffee leaf rust, the worst disease of coffee. Germination of H. vastatrix was inhibited up toll 99 % by COs, followed by the mixture of COs-P and P individually (germination inhibition of 96 % and 54 % respectively). Testing those products on detached coffee leaf discs also produced promising results when COs were applied before H. vastatrix inoculation. These results may lead to the discover...

Waste management (New York, N.Y.), Jan 10, 2016

After the ban on sodium arsenite, waste management alternatives to the prevalent burning method, ... more After the ban on sodium arsenite, waste management alternatives to the prevalent burning method, such as the hygienization and biodegradation in solid phase by composting, are required for the pruned material from grapevines affected by various fungi. In this work the dynamics of a fungus associated with vine decay (Diplodia seriata) during the composting process of a mixture of laying hen manure and vine pruning waste (2:1w/w) have been investigated in an open pile and a discontinuous closed biodigester. Through the optimization of the various physical-chemical parameters, hygienization of the infected waste materials was attained, yielding class-A organo-mineral fertilizers. Nevertheless, important differences in the efficiency of each system were observed: whereas in the open pile it took 10days to control D. seriata and 35 additional composting days to achieve full inactivation, in the discontinuous biodigester the fungus was entirely inactivated within the first 3-7days. Finall...

Lucrări Ştiinţifice - Universitatea de Ştiinţe Agronomice şi Medicină Veterinară Bucureşti. Seria B, Horticultură, 2009

Scientific Papers - Series B, Horticulture, 2018

Progress of Cryogenics and Isotopes Separation, 2017

European Journal of Plant Pathology, 2016

The upsurge in fungal diseases that cause grapevine wood rot in young and adult plants remains a ... more The upsurge in fungal diseases that cause grapevine wood rot in young and adult plants remains a major concern for the wine sector. Since pruned vine shoots act as a reservoir of these fungi, there is a need for sanitization methods that can prevent their spread, avoiding plant reinfection. In this work, the effectiveness of dry heat treatments for the disinfection of pruning waste has been investigated. The thermal death of two inocula of Diplodia seriata fungus, associated to black dead arm disease, was studied in vitro at four different temperatures (40, 50, 60 and 65 °C) for different time periods (20, 40, 60, 90, 120 and 150 min) in a dry air incubator. Obtained data confirmed that inhibition increased as a function of temperature and exposure time. First-order and Weibull models were compared to describe D. seriata fungus survival curve kinetics, with high R2 values (0.923 and 0.930, respectively) and high significances (p < 0.001). Both models predict that the time required to reach 99 % mortality at 65 °C would be 143 min, slightly higher than the experimentally determined minimum time of 120 min. The thermal death kinetics data reported herein has direct applications in process design and validation studies of other grapevine-pruning-waste sanitization methodologies.

Handbook of Composites from Renewable Materials

During the last years there have been recorded very hot periods during the summer, deficits of pr... more During the last years there have been recorded very hot periods during the summer, deficits of precipitations, a more reduced growth of the berries, an acceleration of the phenological stages, the harvesting of the grapes being proceeded with up to two weeks. Also, there have been recorded increased accumulations of sugars in the grapes outrunning with 30 g/l the values obtained during normal years. The year 2007, the hottest in the last decade, with a pronounced deficit of precipitations from the interval May-August determined a predominance of a productive activity and high content of sugar (224.1 g/l in Guyot on demi-high trunk, 216.2 g/l in Cazenave cordon and 202.7 g/l in spur-pruned cordon). Pursuant to these changes there have also been recorded differentiated distributions of the dry matter between the various organs of the vines. The climate warming accentuated in the last years has influences positively the quality of grapes allowing the acquirement of high quality wines.

Agronomy

Fusarium culmorum is a soil-borne fungus able to cause Fusarium head blight, one of the most impo... more Fusarium culmorum is a soil-borne fungus able to cause Fusarium head blight, one of the most important cereal diseases worldwide, which can result in significant yield losses of up to 50% and which jeopardizes food and feed safety due to the mycotoxins produced. In the study presented herein, the enhancement of the antifungal activity against this pathogen, resulting from the addition of silver nanoparticles (AgNPs) to different polyphenol-stevioside inclusion compounds, dispersed either in a chitosan oligomers hydroalcoholic solution or in a choline chloride:urea:glycerol deep eutectic solvent, was investigated in vitro. The polyphenols assayed were curcumin, ferulic acid, gallic acid and silymarin. Four composite concentrations (62.5, 125, 250 and 500 µg·mL−1), with and without AgNPs, were assessed, finding noticeable differences in mycelial growth inhibition, with EC50 and EC90 values ranging from 118 to 579 µg·mL−1 and from 333 to 2604 µg·mL−1, respectively. The obtained results...

AgriEngineering

Phytophthora cinnamomi is responsible for radical rot in a wide range of hosts, resulting in larg... more Phytophthora cinnamomi is responsible for radical rot in a wide range of hosts, resulting in large economic and ecological losses worldwide. In Spain, it is responsible for diseases such as the oak decline or the chestnut blight. In this study, different polyphenol-stevioside inclusion compounds dispersed in a hydroalcoholic solution of chitosan oligomers have been investigated, with a view to their application as natural bioactive complexes to replace conventional systemic fungicides against this fungus. The polyphenols tested in vitro were curcumin, ferulic acid, gallic acid and silymarin. Three concentrations (125, 250 and 500 µg·mL−1) were assayed, with and without silver nanoparticles (AgNPs), and notable differences were found in the inhibition of mycelium growth, with EC50 and EC90 values ranging from 171 to 373.6 µg·mL−1, and from 446.2 to 963.7 µg·mL−1, respectively. The results obtained showed that the addition of AgNPs, despite their antimicrobial activity, did not always...

Congreso Ibérico de Agroingeniería

Congreso Ibérico de Agroingeniería

The upsurge in fungal diseases that cause grapevine wood rot in young and adult plants remains a ... more The upsurge in fungal diseases that cause grapevine wood rot in young and adult plants remains a major concern for the wine sector. So as to study the effectiveness of heat treatments for the sanitization of pruning waste, the thermal death of two inocula of Diplodia seriata fungus-associated to black dead arm disease-was studied in vitro at different temperatures in a dry air incubator, confirming that inhibition increased as a function of temperature and exposure time. First-order and Weibull models were compared to describe D. seriata fungus survival curve kinetics, with high R 2 values (0.923 and 0.930, respectively) and high significances (p<0.001) for both models. According to the first-order model, the time required to reach 100% mortality at 65 °C was 120 min (or 93 min to 95%), whereas for the Weibull model a 90% reduction was attained after 73 min.

Antibiotics (Basel, Switzerland), Jan 16, 2018

“Agriculture for Life, Life for Agriculture” Conference Proceedings

Broad scale use of chemical pesticides is known to have produced broad scale environmental impact... more Broad scale use of chemical pesticides is known to have produced broad scale environmental impact worldwide and, at the same time, discovery and registration of new molecules to be used as insecticides, herbicides and fungicides have slowed significantly along the last decades, reducing the number of options for pest control by the farmers. Searches for novel environmentally friendly products are a recognized priority. In this work, aqueous solutions of chitosan oligomers (COs) and propolis (P), individually or as binary mixtures, were tested against Hemileia vastatrix, the fungus which causes coffee leaf rust, the worst disease of coffee. Germination of H. vastatrix was inhibited up toll 99 % by COs, followed by the mixture of COs-P and P individually (germination inhibition of 96 % and 54 % respectively). Testing those products on detached coffee leaf discs also produced promising results when COs were applied before H. vastatrix inoculation. These results may lead to the discover...

Waste management (New York, N.Y.), Jan 10, 2016

After the ban on sodium arsenite, waste management alternatives to the prevalent burning method, ... more After the ban on sodium arsenite, waste management alternatives to the prevalent burning method, such as the hygienization and biodegradation in solid phase by composting, are required for the pruned material from grapevines affected by various fungi. In this work the dynamics of a fungus associated with vine decay (Diplodia seriata) during the composting process of a mixture of laying hen manure and vine pruning waste (2:1w/w) have been investigated in an open pile and a discontinuous closed biodigester. Through the optimization of the various physical-chemical parameters, hygienization of the infected waste materials was attained, yielding class-A organo-mineral fertilizers. Nevertheless, important differences in the efficiency of each system were observed: whereas in the open pile it took 10days to control D. seriata and 35 additional composting days to achieve full inactivation, in the discontinuous biodigester the fungus was entirely inactivated within the first 3-7days. Finall...