Renata Pawlak

Dr. Renata Pawlak


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 January 2022 in Agronomy
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MSMałgorzata Szostek
Małgorzata Szostek
Ewa Szpunar-KrokEwa Szpunar-Krok
Ewa Szpunar-Krok
RPRenata Pawlak
Renata Pawlak
Jadwiga Stanek-TarkowskaJadwiga Stanek-Tarkowska
Jadwiga Stanek-Tarkowska
Anna IlekAnna Ilek
Anna Ilek
The aim of the study was to compare the effect of conventional, simplified, and organic farming systems on changes in the content of soil organic carbon, organic matter fractions, total nitrogen, and the enzymatic activity. The research was conducted from 2016–2018 on arable land in the south-eastern part of Poland. The selected soils were cultivated in conventional tillage (C_Ts), simplified tillage (S_Ts), and organic farming (O_Fs) systems. The analyses were performed in soil from the soil surface layers (up to 25 cm depth) of the experimental plots. The highest mean contents of soil organic carbon, total nitrogen, and organic matter fractions were determined in soils subjected to the simplified tillage system throughout the experimental period. During the study period, organic carbon concentration on surface soil layers under simplified tillage systems was 31 and 127% higher than the soil under conventional tillage systems and organic farming systems, respectively. Also, the total nitrogen concentration in those soils was more than 40% and 120% higher than conventional tillage systems and organic farming systems, respectively. Moreover, these soils were characterised by a progressive decline in SOC and Nt resources over the study years. There was no significant effect of the analysed tillage systems on the C:N ratio. The tillage systems induced significant differences in the activity of the analysed soil enzymes, i.e., dehydrogenase (DH) and catalase (CAT). The highest DH activity throughout the experiment was recorded in the O_Fs soils, and the mean value of this parameter was in the range of 6.01–6.11 μmol TPF·kg−1·h−1. There were no significant differences in the CAT values between the variants of the experiment. The results confirm that, regardless of other treatments, such as the use of organic fertilisers, tillage has a negative impact on the content of SOC and organic matter fractions in the O_Fs system. All simplifications in tillage reducing the interference with the soil surface layer and the use of organic fertilisers contribute to improvement of soil properties and enhancement of biological activity, which helps to maintain its productivity and fertility.

3 February 2022 in Agronomy
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Ewa Szpunar-KrokEwa Szpunar-Krok
Ewa Szpunar-Krok
MSMałgorzata Szostek
Małgorzata Szostek
RPRenata Pawlak
Renata Pawlak
JGJózef Gorzelany
Józef Gorzelany
Dagmara MigutDagmara Migut
Dagmara Migut
The aim of the research was to determine the effect of fertilising with various doses of ash from biomass combustion (D2–D6) compared to control plots and classic NPK (D1) fertiliser on the morphological and mechanical properties of potato tubers (Solanum tuberosum L.). The field experiment was carried out in the years 2019–2021 (south-eastern Poland, 49°59′ N, 21°57′ E) on two types of soil: Gleyic Chernozem (silty loam) and Haplic Luvisol (silt). The values of mechanical parameters, such as the peel and flesh punching force (FD), deformation (DR) and energy (ED) needed to destroy the test sample, were assessed. The biometric features of the tubers were also assessed. It was found that tubers obtained from the experimental fields where D3 and D4 ash fertiliser doses were applied (corresponding to doses of 188 and 282 kg∙ha−1 K) had the highest tuber yields and the highest resistance to mechanical damage under quasi-static loads. Ash from biomass combustion can be an alternative to conventional mineral fertilizers and can be used in the development of mineral fertilization plans for sustainable agriculture, which will help to solve the problem of storage of this waste.

10 November 2020 in Agronomy
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Ewa Szpunar-KrokEwa Szpunar-Krok
Ewa Szpunar-Krok
MJMarta Jańczak-Pieniążek
Marta Jańczak-Pieniążek
Dagmara MigutDagmara Migut
Dagmara Migut
KSKarol Skrobacz
Karol Skrobacz
TPTomasz Piechowiak
Tomasz Piechowiak
Maciej BalawejderMaciej Balawejder
Maciej Balawejder
We investigated the changes in the physiological and biochemical properties of potato plants exposed to differing ozone (O3) concentrations (5 ppm, 10 ppm) and exposure times (2, 4, 8, 12, 16 min) to determine the safe dose that could be used in crop protection programs. We measured the gas exchange, relative chlorophyll content, chlorophyll fluorescence and total antioxidant capacity in potato leaves exposed to O3 fumigation. The fresh weight (FW) of the aboveground part of the plants and a visual assessment of plant condition were determined after the end of the experiment. The plants were given two O3 treatments and measurements were carried out four times: on the 1st and 7th day after treatment. We conclude that O3 exposure time had a greater impact on the reduction in the efficiency of the potato photosynthetic apparatus than O3 concentration. Research has showed that O3 in 5 ppm concentration for 2 and 4 min and 10 ppm for 2 min increased the efficiency of the photosynthesis and antioxidant activity in leaf processes, and these doses could be taken into account in further research on the potential for using O3 in potato protection.

5 July 2022 in Molecules
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Karolina PyciaKarolina Pycia
Karolina Pycia
Ewa Szpunar-KrokEwa Szpunar-Krok
Ewa Szpunar-Krok
MSMałgorzata Szostek
Małgorzata Szostek
RPRenata Pawlak
Renata Pawlak
LJLesław Juszczak
Lesław Juszczak
The aim of the study was to assess the effect of soil type and the application of fertilizer composed of ashes from biomass combustion to potatoes on selected physicochemical, rheological, and thermal properties of potato starches isolated by using the laboratory method. Potatoes were grown in Haplic Luvisol (HL) and Gleyic Chernozem (GC) soil and fertilized with different doses of biomass combustion ash (D1–D6) with different mineral contents. The thermodynamic characteristics of gelatinization and retrogradation were identified by DSC. The analyses of rheological properties included the determination of the gelatinization characteristics by using the RVA method, flow curves, and assessment of the viscoelastic properties of starch gels. It was found that the starches tested contained from 24.7 to 29.7 g/100 g d.m. amylose, and the clarity of 1% starch pastes ranged from 59% to 68%. The gelatinization characteristics that were determined showed statistically significant differences between the starches analyzed in terms of the tested factors. The value of maximum viscosity and final viscosity varied, respectively, in the range of 2017–2404 mPa·s and 2811–3112 mPa·s, respectively. The samples of the potato starches studied showed a non-Newtonian flow, shear thinning, and the phenomenon of thixotropy. After cooling, the starch gels showed different viscoelastic properties, all of which were weak gels (tan δ = G″/G′ > 0.1).

23 December 2023 in Agriculture
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MJMarta Jańczak-Pieniążek
Marta Jańczak-Pieniążek
WPWojciech Pikuła
Wojciech Pikuła
RPRenata Pawlak
Renata Pawlak
BDBarbara Drygaś
Barbara Drygaś
Ewa Szpunar-KrokEwa Szpunar-Krok
Ewa Szpunar-Krok
Soil salinity stress is a serious problem in plant cultivation. The effect of this stress is to disrupt the photosynthetic process, which can cause growth restrictions and a decrease in plant productivity. The use of biostimulants can be one of the stress mitigation strategies in plant cultivation. Biostimulants increase the tolerance of plants to abiotic stresses, thus mitigating their adverse effects. In the present study, based on a pot experiment, the effect of foliar application of biostimulants differentiated in terms of chemical composition (Bombardino (B1), Quantis® (B2), Biofol Plex (B3) and Megafol (B4)) on the physiological properties of Chinese silver grass (Miscanthus sinensis (Anderss.)) plants growing under salt stress conditions was determined. Salt stress was induced by soil application of NaCl at concentrations of 200 and 400 mM. The application of salt solutions was followed by spraying Miscanthus plants with biostimulants using a hand-held sprayer. Physiological investigations (chlorophyll content, chlorophyll fluorescence and gas exchange) have been carried out twice: on the 1st (Term I) and 7th (Term II) day after spraying with biostimulants. It was shown that salt stress causes a decrease in the values of most of the physiological indicators tested (except Ci). On both measurement dates, the application of biostimulants, especially B2, caused an improvement in the values of the physiological indices studied, both for plants growing under optimal conditions and under salt stress. Term II showed an upward trend in most of the analyzed parameters compared to Term I, indicating plant acclimatization to stress conditions. Conducted studies have shown that using biostimulants contributes to the alleviation of the effects of soil salinity stress. The implementation of these practices can contribute to the advancement of sustainable farming.

19 January 2021 in Agronomy
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Ewa Szpunar-KrokEwa Szpunar-Krok
Ewa Szpunar-Krok
Piotr KuźniarPiotr Kuźniar
Piotr Kuźniar
RPRenata Pawlak
Renata Pawlak
Dagmara MigutDagmara Migut
Dagmara Migut
The aim of the study was to investigate the effect of foliar fertilization on the morphological and mechanical properties of pea seeds (Pisum sativum L.) and to determine the dependences between the morphological features and chemical composition of pea seeds and their susceptibility to mechanical damage. Field experimentation was carried out in 2015–2017 (south-eastern Poland, 49°59′ N, 21°57′ E). Micronutrient conventional fertilization (N1) and organic fertilizer (N2) were tested on eight pea cultivars. The mechanical parameters assessed included compression force (FD), relative deformation (DR), and energy (ED). Application of foliar fertilizer increased the strength of seeds and their ability to resist mechanical damage under quasi-static loads. The seeds of plants fertilized with N1 were more resistant to mechanical damage than the seeds of plants fertilized with N2. Seeds with larger dimensions, mass, density, and a more spherical shape were damaged under the action of less force and energy, and they deformed less. Seeds with higher protein, fat, ash, and K content and lower NFE, Fe, Zn, and Cu content were more resistant to mechanical damage. The mathematical models created provide knowledge about the impact of foliar fertilizer on the mechanical properties of seeds.