Rudolf Kastori

Evaluation of grain yield and its components in wheat cultivars and landraces under near optimal and drought conditions

In a 2-years experiment, 30 wheat cultivars and 21 landraces from different countries were tested under near optimum and drought stress conditions. Plant height, number of sterile spikelets per spike, spikelets per spike, number of kernels per spike, kernel weight per spike, 1000 kernel weight and grain yield were evaluated. The number of kernels per spike, 1000 kernel weight and especially yield were more sensitive to drought stress in the cultivars than plant height and number of spikelets per spike, while in the landraces these traits did not differ under drought stress compared to near optimum conditions. The average yield of cultivars was significantly better than the average yield of landraces under near optimum as well as drought stress conditions. Path coefficient analysis showed that for cultivars under near optimum conditions there was no significant direct association of any of the analysed characters with yield, while under drought stress conditions, number of kernels per spike had a significant positive direct effect. Under drought stress conditions, the number of sterile spikelets displayed a negative direct effect, while kernel weight per spike had a positive direct effect on yield. Hierarchical cluster analysis was used as a tool to classify cultivars and landraces according to their yield ability under near optimum and drought stress conditions. Among the cultivars, two groups out of five and among one of three in the landraces were characterised by high yields in both near optimum as well as under drought stress conditions. These genotypes may serve as sources of germplasm for breeding for drought tolerance.

Effect of excess lead on sunflower growth and photosynthesis

Abstract The effect of different lead (Pb) concentrations in the nutrient solution on the growth, Pb and chlorophyll a+b content, chlorophyll fluorescence and quenching parameters in the leaves of young sunflower (Helianthus annuas L.) plants was studied. The content of Pb in the analyzed plant parts increased following the increase in Pb content in the nutrient medium. This increase was expressed to a higher extent in the roots than in the stems and leaves. In the presence of high concentration of Pb in the leaf area, the dry mass and the height of plants were reduced. Lead treatment of sunflower plants led to a pronounced reduction of chlorophyll (a+b) content, accompanied by much smaller decrease of photosynthetic O evaluation rate and PSll efficiency at low light intensity. Hence, Pb effect2did not result in the destruction of the photosynthetic apparatus, but in its reduction. The highest Pb concentration in the nutrient solution induced, however, at saturating photon flux density (PFD) a decrease in...

Photosynthesis, chlorophyll fluorescence and soluble carbohydrates in sunflower leaves as affected by boron deficiency

Abstract The effect of various boron levels in the nutrient solution on the growth, boron and chlorophyll content, photosynthesis and chlorophyll fluorescence in the leaves of young sunflower (Helianthus annuus L.) plants was studied under greenhouse conditions. Deficiency of boron decreased the dry matter yield of the roots, shoots and leaves. The content of boron in all analyzed plant parts increased with the increase of boron levels in the nutrient solution, more so in the shoots than in the roots. Leaf area was reduced under boron deficiency as well as the content of chlorophyll in the leaves. The content of analyzed sugars was increased in boron deficient plants, glucose content exhibited the highest increase under boron deficiency. Boron deficiency appreciably decreased photosynthetic oxygen evolution by leaves, the apparent quantum yield and quantum efficiency of photosystem two electron transport. The diminished rate of photosynthesis in boron deficient sunflower leaves could be correlated to the ...

Effect of bicarbonate and Fe supply on Fe nutrition of grapevine.

Abstract Grapevine grafts (Vitis vinifera L. cv. Riesling, on rootstocks of Vitis sp. L. cv. 5BB) were grown hydroponically in complete nutrient solution (control), Fe‐free nutrient solution and complete nutrient solution with added 10 mM HCO3 −. The concentration of total chlorophyll was significantly reduced in Fe deficient plants, particularly in HCO3 − supplied nutrient solution. The concentration of extracellular (extraplasmatic) root Fe decreased in the case of ‐Fe treatment and increased in that of HCO3 − treatment, while the concentration of symplastic Fe decreased in both treatments. However, the concentration of total root Fe decreased in roots of plants grown in ‐Fe solution and increased in those grown in HCO3 − supplied solution. Fe‐deficient plants showed lowering of total Fe and “active Fe” (extractable in 1 M HCl or o‐phenanthroline) concentration in leaves. These results indicate that bicarbonate in the nutrient solution may be a major inducing factor of Fe‐deficiency chlorosis in grapevine presumably due to inhibited Fe acquisition by roots, but do not confirm Fe inactivation in leaves.

Photosynthesis, chlorophyll fluorescence, and water relations in young sugar beet plants as affected by sulfur supply

Abstract The effect of different concentrations of sulfur (1 and 3 mM) and interruption of sulfur (S) supply for 25 days on the photosynthesis and leaf water relations in young sugar beet plants (Beta vulgaris L.) was studied in water culture, under greenhouse conditions. Interruption of S‐supply significantly reduced the content of sulfur, chlorophylls a+b and carotenoids, leaf area, density of stomatal and epidermal cells, transpiration rate and leaf water potential, while it increased the free proline content and stomatal diffusion resistance. An increase in S concentration in the nutrient medium from 1 to 3 mM did not significantly affect the tested parameters, except for an increase in leaf S content and a decrease of leaf water potential. Sulfur deficiency caused a pronounced decrease of the rate and quantum yield of photosynthetic oxygen evolution under non‐photorespiratory conditions. This was partly the result of the diminished photochemical efficiency of photosystem II reaction centers. Less efficient excitation of PSII reaction centers is most probably the consequence of higher thermal energy dissipation in the reaction centers of S‐starved plants. These data support that S nutrition is one of the factors regulating plant photosynthesis.

Rare earth elements: Yttrium and higher plants

Rare earth elements (REEs) form a chemically uniform group with very similar physical and chemical properties. The REEs include the elements scandium, yttrium, and the lanthanides from lanthanum to lutetium. They are widely distributed and present in all parts of the biosphere. REEs are required in industry, agriculture, medicine, biotechnology, environmental problems and many other fields. Lately, many experiments show their positive or negative, first of all nonspecific, effect on life processes of higher plants as well as growth and yield of cultivated species, but the physiological mechanisms are still not well understood. It has been determined that yttrium is widely distributed in plants, as well as that certain plant species uptake yttrium at different extent. Its highest accumulation is in the root and the leaf. Although yttrium was discovered more than two centuries ago, its effect on higher plants - their anatomical and morphological built, physiological and biochemical processes etc. - is very little known. One of the basic reasons is that yttrium, as well as other REEs elements, according to current knowledge, is not biogenic for higher plants and - wider - for live organisms. The objective of this paper is to concisely show previous knowledge about yttrium in the plant world.

Effect of yttrium on photosynthesis and water relations in young maize plants

Abstract Despite an increase in spectrum of industrial applications of yttrium (Y) and the fact that it is widely present in the soils and plants, some of which are agronomically important crops, its effects on plant growth and metabolism are still obscure. Therefore, the aim of this work was to examine the effect of different concentrations of Y on its accumulation and distribution, photosynthetic responses, water relations, free proline concentration and growth of young maize plants. The experiment was done with maize ( Zea mays L., hybrid NS-640), in water cultures, under semi-controlled conditions of a greenhouse. Plants were supplied with half-strength complete Hoagland nutrient solution, to which was added either 0 (control), 10 −5 , 10 −4 or 10 −3 mol/L Y, in the form of Y(NO) 3 ·5H 2 O. Each variant was set in thirteen replications, with six plants in each replication. Plants were grown for 21 d and they were at the stage of 3 and 4 leaves when they were analyzed. The presence of Y reduced maize growth and photosynthetic performance. Dimensions of stomata significantly decreased while their density significantly increased on both adaxial and abaxial epidermis. Plant height, root length, total leaf area and dry mass also declined. Concentration of photosynthetic pigments (chl a and b and carotenoids) and free proline decreased. Photosynthesis and transpiration were impaired in the presence of Y – their intensities were also reduced, and the same stands for stomatal conductance of water vapor, photosynthetic water use efficiency (WUE) and water content. Although the highest concentration of Y was found in maize roots in each treatment, Y concentration in the second leaf and shoot also significantly increased with an increase in Y concentration in the nutrient solution. Albeit Y concentration was much higher in roots than in shoots, shoot metabolism and growth were much more disrupted. The results demonstrated that young maize plants accumulated significant amount of Y and that this element, when present in higher concentrations, had unfavorable effect on physiological processes and therefore plant growth.

Genetic variability of concentration of microelements in wild sunflower species and hybrids.

The aim of this work was to investigate genetic specificity of sunflower nutrition with microelements. Therefore, concentrations of essential (Zn, B, Mn, Cu, Fe and Ni) and non-essential (Cr, Al, Cd, As, Pb and Ba) micronutrients were analyzed. Five sunflower hybrids the most grown in Serbia and different populations of wild sunflower species originating from North America: Helianthus neglectus Heiser (3), Helianthus agrophyllus T&G (3), Helianthus petiolaris Nutt. (2), Helianthus annuus L. (4) were included in the experiment. Populations of wild sunflower species and hybrids differed significantly with respect to the concentration of analyzed elements. Manganese concentration was significantly higher in hybrids than in wild species. In all genotypes Fe, B and Mn had the highest concentration. Coefficient of variation of microelement concentration depended on genotype and particular element. In wild populations, for essential microelements, it was between 3.7 and 59.5, whereas in hybrids it varied from 10.0 to 48.8. Coefficient of variation of concentration of non-essential microelements in wild populations varied from 7.7 to 73.8, and in hybrids from 15.1 to 48.8. Average coefficient of variation in both wild species and hybrids was the lowest for Mn and Pb. It was the highest for Cr, Ni, and Zn in hybrids and for Cd, Ni, and Cr in wild species. The results suggest that genetic specificity with respect to uptake of microelements in wild species and hybrids is highly expressed. Broad genetic variability of concentrations of microelements in wild species and hybrids indicate that their reactions to deficiency and/or excess of those elements probably are not the same either. This finding may be used in breeding process aimed specifically at improvement of tolerance and capacity to accumulate microelements in sunflower. Phytoremediation technology designed to reduce the amount of microelements in the soil could thus be advanced by utilization of such plants.

Nickel translocation from seed during germination and growth of young maize plants.

Effect of different concentrations of nickel (0, 10-5, 10-4, 10-3 and 10-2 mol Ni/dm3) present at the time of maize seed imbibition, on concentration, distribution and nickel accumulation coefficient in the root and the shoot, biological value of the seed and growth of young plants was investigated. It was found that during germination the nickel from the seed is intensively translocated to the root and shoot of young plants. With increase of applied concentrations of nickel, its concentration in the root and shoot increased as well. Nickel concentration and accumulation coefficient were higher in the root than in the shoot except at the highest applied concentration when the result was opposite. The highest applied concentration of nickel increased percentage of atypical seedlings and non-germinated seeds and decreased percentage of typical seedlings, germination energy and seed germination ability. Nickel implementation did not affect the growth and mass of the shoot. Root mass and length of the primary root decreased at the highest concentration of nickel, which led to change in shoot and root mass ratio. Based on the obtained results it can be concluded that only the highest applied nickel concentration affected the biological value of the seed and the growth of young maize plants, regardless of its intensive accumulation in the root and the shoot, which indicates a significant tolerance of maize in initial phases of growth to presence of high nickel concentration. Intensive translocation of nickel during germination into newly formed organs points to its good mobility and potential possibility to enter the food chain from a contaminated seed.

Effect of selenium, molybdenum and zinc on seedling growth and frequency of grain weevil (Sitophilus granarius) in triticale grains

The effects of different doses (0, 90, 270, 810 kg/ha) of selenium, molybdenum and zinc microelements on their translocation and accumulation in grains, seedling growth and grain infestation were examined under field conditions on a calcareous chernozem soil. Thirteen years after the application of selenium, molybdenum and zinc, significant translocation and accumulation of these elements in the grain were established, indicating a long-term effect of these microelements on triticale plants. The highest degree of accumulation in grains and seedling shoots was found for selenium, then molybdenum, while the detected amounts of zinc were significantly lower. The degree of accumulation of all three microelements in the grain and seedling shoot increased as doses increased. Translocation index from shoot to grain at the grain-filling phase was the highest when zinc was used, then selenium, and the lowest when molybdenum was applied. The highest translocation index from the grain during germination into seedling shoots was obtained with zinc, then molybdenum and selenium. Translocation indexes of the investigated elements significantly decreased as the doses of elements increased. Dry weight of seedling shoots decreased as molybdenum and zinc in grain increased. High selenium concentration moderately stimulated seedling development, pointing out a high tolerance of triticale to higher concentration of this microelement at initial development stages. Infestatation with grain weevil was provoked by high concentrations of these microelements in the grain. High concentrations of zinc and selenium, in particular, significantly decreased the percentage of damaged grains, while molybdenum moderately increased their numbers. The effect of zinc and molybdenum may be attributed to their chemical effect, while selenium effect may also be referred to a negative effect of the volatile selenium compound. The effect of selenium, molybdenum and zinc contamination of grains on the seedling growth and frequency of grain weevil was different, and the emphasis was on selenium.