The seasonal senescence of leaves in the phenological cycle coincides with the change of their strength properties which determine resistance to environmental conditions and the efficiency of the ...photosynthesis process. That affects the development, growth and condition of the plant. Therefore, the aim of this paper was to observe and compare the results of strength tests performed on the leaves of two species of trees popular in Poland - lime and maple. As well as chlorophyll fluorescence and photosynthetic pigments content in the context of the changes occurring during the entire leaf life cycle. Obtained results showed that the strength properties of the tested leaves reached the minimum values in spring and the maximum in the summer similarly to the leaf greenness index. Whereas the fluorescence increased which the seasonal senescence in opposition to the photosynthesis efficiency of the leaves. Collected data revealed that strength parameters and photosynthetic pigment content were significantly higher for maple leaves than for lime leaves. Studies showed differences between physiological and mechanical properties of the leaves of two trees species, even if they grew under the same environmental conditions. It is concluded from the results that phenotype and physical parameters of leaves are related to seasonal senescence.
Abstract
The study analyses the impact of alternating (magnetic induction B = 30 mT for t = 60 s) and constant magnetic fields (B = 130 mT for t = 17 h) and alternating electric fields (electric ...current E = 5 kV/cm for t = 60 s) on various growth parameters of soy plants: the germination energy and capacity, plants emergence, the fresh mass of seedlings, protein content (Kjeldahl’s method), and photosynthetic parameters (with MINI-PAM 2000 WALTZ Photosynthesis Yield Analyser and a SPAD-502 Chlorophyll Meter). Four cultivars were used: MAVKA, MERLIN, VIOLETTA, and ANUSZKA. Moreover, the advanced Machine Learning processing pipeline was proposed to distinguish the impact of physical factors on photosynthetic parameters. The use of electromagnetic fields had a positive impact on the germination rate in MERLIN seeds. The best results in terms of germination improvement were observed for alternating magnetic field stimulation in all cultivars (p > 0.05). For the VIOLETTA cultivar an increase (p > 0.05) in the emergence and overall number of plants as well as fresh mass was observed after electromagnetic field stimulation. For the MAVKA and MERLIN cultivars, the concentration of proteins in the leaves was noticeably higher in plants grown from seeds stimulated using a constant magnetic field.
Abstract
The aim of the study was to measure the tensile strength of 4-year-old alfalfa leaves cultivated from seeds exposed to pre-sowing stimulation with He–Ne laser light for 1 or 5 min ...(designated respectively as F1 and F5) and alternating magnetic field with the exposure time of 1 or 5 min (respectively, L1 and L5). The leaves were measured in terms of blade length and width as well as petiole thickness prior to the tensile test. Measurements were also conducted to determine the chlorophyll fluorescence lifetime and content of photosynthetic pigments (chlorophyll
a
,
b
,
a
+
b
and carotenoids). The observed tensile strength was between 1.59 and 2.45 N. In the test group, the observed strength was lower in leaves collected from the top and central section of the stem but higher in the bottom part of the stem as compared to the control. The maximum increase of the tearing tensile force relative to the control (C) was observed for the L1 and F1 stimulation samples in leaves collected from the top and bottom parts of the stem, while the maximum decrease for that force was recorded for L5 leaves from the middle and top part of the stem. Chlorophyll fluorescence lifetimes and the overall content of photosynthetic pigments (chlorophyll
a
and
b
and carotenoids) were noticeably decreased in the leaves subjected to the stressors/stimulants applied. The results obtained for F1, L5 and, L1 stimulation revealed a decrease in fluorescence lifetimes. The content of photosynthetic pigments was also decreased under the influence of laser light stimulation (L1). This was a clear indication of plant ageing.
Due to the common trend towards limitation of excessive use of chemicals in agriculture, there is a growth of interest in methods of seed quality improvement that would be safe for the environment. ...These include methods based on the effect of various physical factors, such as laser light, magnetic field, seed treatment with magnetized water, electric field. The work provides detailed information on the impact of seed stimulation of these factors on germination, growth, development and yielding of horticultural plants. Summarizing the results of the study, it can be concluded that the application of physical factors in appropriate doses can be an effective way to enhance many plant parameters that increase their productivity. The beneficial effects of seed stimulation are mainly related to the first stages of plant life, i.e. – germination, emergence and growth of seedlings. In many cases, the enhancement of these features is also the result of the increase of plant yields. The increase of yield is even several dozen percent. The results of the study encourage the implementation of these physical methods of seed quality improvement into agricultural and horticultural practice.
The study pertained to environmentally-friendly methods in the cultivation of cereal, and aimed to manage the quality of rye and triticale seeds and determine the impact of seed conditioning using ...effective microorganisms (EM), red light (RL), and a combination of the two (RL × EM) on the yield of grain and straw. Moreover, the seeds were sown into soil with and without EM conditioning, designated as 0 and PEM. The yield fluctuations depended mostly on the studied rye and triticale cultivars. The best effects we observed in soil without EM conditioning for Dańkowskie Złote rye and Moderato triticale. The increase in grain and straw yields was, respectively: 26% (RL), 31% (RL × EM), 40% (EM), and 17% (RL × EM), 23% (RL), 32% (EM) – Dańkowskie Złote, 27% (RL × EM), 44% (EM), 46% (RL), and 17% (RL × EM), 51% (EM), 78% (RL) – Moderato. In turn, seeds exposed to the experimental treatment and sown into soil containing EM produced reduced yields in both of the above cultivars. It is noteworthy that the conditioning methods employed in the field experiment can facilitate increased yields but most importantly contribute to the resilience of agrosystems and can therefore have environmental benefits. It is noteworthy that the conditioning methods employed in the field experiment can facilitate increased yields but most importantly contribute to the resilience of agrosystems and can therefore have environmental benefits.
This paper presents the results of a study on the effects of red light treatment of sweet corn seeds on the quantity and quality of the subsequent yield (total and marketable), as well as the length ...of cobs and thousand kernel weight. The respective groups of kernels were exposed to light: 1—once (K1), 2—twice (K2), and 3—thrice (K3); the control seeds were untreated. The light treatment had a positive impact on the analyzed values. Relative to the control, we observed a yield increase of approx. 5% for the Basin cultivar and approx. 25% for the Shaker and Powerhouse cultivars under the K2 mode. We also recorded an increase in the percentage of marketable yield of approx. 20%, 45%, and 48%, respectively for the Shaker, Powerhouse, and Basin cultivars. Positive effects were also observed in terms of cob length and thousand kernel weight for all treatment modes and cultivars analyzed. The obtained results support the inclusion of this method in the scope of recommendable agrotechnical practices aimed at improving the quantity and quality of yields of various crops and vegetables.
Drying as an effective method for preservation of crop products is affected by various conditions and to obtain optimum drying conditions it is needed to be evaluated using modeling techniques. In ...this study, an adaptive neuro-fuzzy inference system (ANFIS), artificial neural network (ANN), and support vector regression (SVR) was used for modeling the infrared-hot air (IR-HA) drying kinetics of parboiled hull. The ANFIS, ANN, and SVR were fed with 3 inputs of drying time (0–80 min), drying temperature (40, 50, and 60 °C), and two levels of IR power (0.32 and 0.49 W/cm2) for the prediction of moisture ratio (MR). After applying different models, several performance prediction indices, i.e., correlation coefficient (R2), mean square error index (MSE), and mean absolute error (MAE) were examined to select the best prediction and evaluation model. The results disclosed that higher inlet air temperature and IR power reduced the drying time. MSE values for the ANN, ANFIS tests, and SVR training were 0.0059, 0.0036, and 0.0004, respectively. These results indicate the high-performance capacity of machine learning methods and artificial intelligence to predict the MR in the drying process. According to the results obtained from the comparison of the three models, the SVR method showed better performance than the ANN and ANFIS methods due to its higher R2 and lower MSE.
The study aimed to determine the impact of laser light (L), magnetic stimulation (p) and silver nanocolloid (AgNC) on pumpkin seeds on the germination rate and content of photosynthetic pigments as ...well as the efficiency of photosynthesis and greenness index in the plant’s development stages. Seeds germinated after the use of various combinations of different refining techniques. The best results were observed for the alternating magnetic field, where the germination energy increased significantly by 20% relative to the control. A similar effect was observed in terms of germination capacity which increased by 4%. A decrease in terms of emergence rate was observed in all study groups. Leaves grown from seeds soaked in nanocolloidal silver on platters were characterised by a significantly higher content of chlorophyll a and b by, respectively, 53 and 11%, as well as 79% higher carotenoid content. The leaves of potted plants contained 42 and 43% more chlorophyll a in groups p and AgNC. In addition, 66 and 81% more carotenoids in groups L and p. At the stage of the onset of flowering of pumpkin, an improvement in terms of photosynthetic efficiency and greenness index was observed in all study groups. The highest improvement was recorded for seeds soaked in silver and reached 23% (intensity of photosynthesis) and 11% (greenness index SPAD).
The aim of the study was to determine the impact of red light (RL) and effective microorganisms (EMs) on the wheat yield of grain and straw, as well as the quality (protein, carbohydrates, gluten, ...index of sedimentation (SDS index), germination capacity). Moreover, the experiments measured the granulometric composition and pH of soil, as well as its content of microelements and major nutrients, including heavy metals. The field experiment was conducted in 2017, 2018, and 2019 at the experimental station (Felin) of the University of Life Sciences in Lublin (Poland). The best results in terms of overall yield, protein content, and SDS index were obtained after the red light treatment (RL). The three-year application of effective microorganisms (EMs) in the soil had a positive impact, relative to the control, on the grain yield, straw yield, starch, SDS index, and germination capacity. A slight decrease was observed in terms of the protein content. After the application of effective microorganisms (EMs) in soil, changes were observed in the soil’s granulometric composition, pH, humus, and microelements.
Celem badań było określenie wpływu stymulacji laserowej nasion na wschody i plonowanie grochu łuskowego. Materiałem do badań były nasiona 6 partii grochu o różnej jakości wyrażonej zdolnością ...kiełkowania. Nasiona traktowano 3 dawkami światła lasera He-Ne (0, 6 i 8 mW · cm–2). W doświadczeniu polowym oceniano wschody siewek, liczbę strąków na roślinie, liczbę nasion w strąku, masę 1000 nasion, plon nasion z jednej rośliny oraz z jednostki powierzchni. Stymulacja laserowa istotnie poprawiła wschody siewek wyrosłych z nasion gorszej jakości. Nasiona wysokiej jakości nie zareagowały zwiększeniem liczby wschodów na przedsiewne traktowanie laserem. Nie stwierdzono istotnego wpływu stymulacji światłem lasera w zastosowanych dawkach na plonowanie nasion grochu.
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