Artur Nosalewicz

Effect of drought and heat stresses on plant growth and yield: a review

Abstract Drought and heat stresses are important threat limitations to plant growth and sustainable agriculture worldwide. Our objective is to provide a review of plant responses and adaptations to drought and elevated temperature including roots, shoots, and final yield and management approaches for alleviating adverse effects of the stresses based mostly on recent literature. The sections of the paper deal with plant responses including root growth, transpiration, photosynthesis, water use efficiency, phenotypic flexibility, accumulation of compounds of low molecular mass (eg proline and gibberellins), and expression of some genes and proteins for increasing the tolerance to the abiotic stresses. Soil and crop management practices to alleviate negative effects of drought and heat stresses are also discussed. Investigations involving determination of plant assimilate partitioning, phenotypic plasticity, and identification of most stress-tolerant plant genotypes are essential for understanding the complexity of the responses and for future plant breeding. The adverse effects of drought and heat stress can be mitigated by soil management practices, crop establishment, and foliar application of growth regulators by maintaining an appropriate level of water in the leaves due to osmotic adjustment and stomatal performance.

Alterations of the lipid content and fatty acid profile of Chlorella protothecoides under different light intensities.

Chlorella protothecoides is a valuable source of lipids that may be used for biodiesel production. The present work shows analysis of the potential of photoheterotrophic cultivation of C. protothecoides under various light intensities aiming to identify the conditions with maximal biomass and lipid content. An increase in light intensity was associated with an increased specific growth rate and a shortened doubling time. Also, the relative total lipid content increased from 24.8% to 37.5% with increase of light intensity. The composition of fatty acid methyl esters was affected by light intensity with the C16-18 fatty acids increased from 76.97% to 90.24% of total fatty acids. However, the content of linolenic acids decreased with the increase of the culture irradiance. These studies indicate that cultures irradiated with high light intensities achieve the minimal specifications for biodiesel quality on linolenic acids and thus are suitable for biodiesel production.

Effect of soil moisture and temperature on N2O and CO2 concentrations in soil irrigated with purified wastewater

Abstract Flooded organic soils are potentially important sources of greenhouse gases. The effect of soil temperature and moisture on the concentration of N2O and CO2 at two depths of organic soil flooded with two doses of purified wastewater was studied. Nitrous oxide concentrations at the 10-30 cm depth range were generally increased with an increase in soil moisture, showing dependence on the aeration status of soil. The maximum values of N2O concentrations were higher at the 50-100 than 10-30 cm depth range, but a similar pattern of increasing maximum values of N2O concentration with an increasing input of nitrogen in treatments at both depth ranges was observed. The maximum concentrations of carbon dioxide within the 50-100 cm depth range remained at a similar level in all treatments reaching 7.1-7.7%, which indicated weak relations with the input of water and nitrogen at this depth range. We conclude that the N2O and CO2 concentrations at 10-30 cm depths in the examined organic soil flooded with 600mm year-1 of purified wastewater exhibited a similar level as the concentrations in soil watered only by precipitation.

Leaching of potassium, magnesium, manganese and iron in relation to porosity of tilled and orchard loamy soil

Abstract The aim of this study was to examine the leaching of potassium, magnesium, manganese and iron in tilled and orchard silty loam soil. The experimental treatments were: conventionally tilled field (CT) with main tillage operations including pre-plough (10 cm)+harrowing followed by mouldboard ploughing to 20 cm depth, and a 35-year-old apple orchard (OR) with a permanent sward. Leaching of the cations was determined in soil columns of undisturbed structure, 21.5 cm diameter and 20 cm height, from a depth of 0–20 cm. All the columns were subjected to spray irrigation at a level of 1110 ml (30 mm), and leachate in 50-ml increments was collected. Concentration of the cations in the leachate was determined using a spectrophotometer ICP-AS. Pore size distribution data showed that the volume of pores >20 µm under CT was greater at a depth of 0–10 cm and lower in the 10–20 cm soil layer under OR, and the reverse was true with respect to pores <6 µm. At each 50-ml leachate, concentration of all the cations was greater under CT than OR. In most leachates the differences were more pronounced for potassium and magnesium than iron and manganese. Percolation of the leachate was considerably faster in orchard than tilled soil.

Aluminium Toxicity to Plants as Influenced by the Properties of the Root Growth Environment Affected by Other Co-Stressors: A Review

Aluminium toxicity to crops depends on the acidity of the soil and specific plant resistance. However, it is also strongly affected by other environmental factors that have to be considered to properly evaluate the resultant effects on plants. Observed weather perturbations and predicted climate changes will increase the probability of co-occurrence of aluminium toxicity and other abiotic stresses.In this review the mechanisms of plant-aluminium interactions are shown to be influenced by soil mineral nutrients, heavy metals, organic matter, oxidative stress and drought. Described effects of aluminium toxicity include: root growth inhibition, reduction in the uptake of mineral nutrients resulting from the inhibition of transport processes through ion channels; epigenetic changes to DNA resulting in gene silencing. Complex processes occurring in the rhizosphere are highlighted, including the role of soil organic matter and aluminium detoxification by mucilage.There is a considerable research gap in the understanding of root growth in the soil environment in the presence of toxic aluminium concentrations as affected by interactions with abiotic stressors. This knowledge is important for the selection of feasible methods aimed at the reduction of negative consequences of crop production in acidic soils affected by adverse growth environment.

Difference in infiltration and macropore between organic and conventional soil management

To clarify the differences in physical aspects (water permeability and macropore) between organically (OR) and conventionally managed (CO) soils, infiltration was measured at an experimental field managed in Puławy, Poland. Soil columns at depths of 0–20 cm (diameter 21.5 cm) were also collected from the field to determine infiltration and flow–active porosity (macropore). The infiltration rate was 6–10 times higher in OR than in CO, owing to larger macropores in OR. The larger macropores in OR could presumably be due to two factors: (1) the fact that compost and clover (Trifolium repens)–grass were applied only to the organically managed field; (2) the larger population of earthworms (Eisenia foetida) in the organically managed field, which prefer applied organic matter and dislike agrochemicals. These findings, of the higher infiltration and the larger macropore in OR than in CO, may demonstrate one positive effect of organic soil management.

Effect of temperature on oxidative stress induced by lead in the leaves of Plantago major L.

Abstract Fluctuation of the summer day-time temperatures in the mid-latitudes in a range from 16 to 30°C should not have irreversible negative effects on plants, but may influence metabolic processes including the oxidative stress. To test the effect of moderately high temperature on oxidative stress induced by lead in the leaves of Plantago major L.; the plants were incubated in a water solution of 0, 150, 450, and 900 μM Pb (NO3)2 at 20 and 28°C. Plant reactions were evaluated by the content of thiobarbituric acid reactive substances and ascorbate peroxidase and glutathione reductase activities in leaves after 2, 24, 48, and 72 h. The Pb concentration in the leaves rose with the increase in the Pb content and was higher at 20°C. The increase in stomatal resistance caused by Pb was higher at 28°C. The contents of TBARS increased after 2 h of plant exposure to Pb and the increase was the highest at 900 μM Pb, 28°C. The AsP activity increased up to 50% after 24 h of Pb-treatment at 28°C; the highest increase in glutathione reductase activity was observed after 72 h at 20°C. Thus, the moderately high temperature 28°C compared with optimal 20°C caused a decrease in Pb accumulation in Plantago leaves but amplified the negative effects of lead, especially in the beginning of stress development.

Leaching Kinetics of Atrazine and Inorganic Chemicals in Tilled and Orchard Soils

Abstract The aim of this study was to verify first-order kinetic reaction rate model performance in predicting of leaching of atrazine and inorganic compounds (K+1, Fe+3, Mg+2, Mn+2, NH4 +, NO3 - and PO4 -3) from tilled and orchard silty loam soils. This model provided an excellent fit to the experimental concentration changes of the compounds vs. time data during leaching. Calculated values of the first-order reaction rate constants for the changes of all chemicals were from 3.8 to 19.0 times higher in orchard than in tilled soil. Higher first-order reaction constants for orchard than tilled soil correspond with both higher total porosity and contribution of biological pores in the former. The first order reaction constants for the leaching of chemical compounds enables prediction of the actual compound concentration and the interactions between compound and soil as affected by management system. The study demonstrates the effectiveness of simultaneous chemical and physical analyses as a tool for the understanding of leaching in variously managed soils.

Rate of Leaching of Organic and Inorganic Compounds in Tilled and Orchard Soils

The first-order kinetic reaction rate model is used in predicting the leaching of atrazine and inorganic compounds (\( {\mathrm{K}}^{+1} \), \( {\mathrm{Fe}}^{+3} \), \( {\mathrm{Mg}}^{+2} \), \( {\mathrm{Mn}}^{+2} \), \( {\mathrm{NH}}_4^{+} \), \( {\mathrm{NO}}_3^{-} \), and \( {\mathrm{PO}}_4^{-3} \)) from tilled and orchard silty loam soils. This model provided an excellent fit to the experimental concentration changes of the compounds vs. time data during leaching. Calculated values of the first-order reaction rate constants for the changes of all chemicals ranged from 3.8 to 19.0 times higher in orchard than in tilled soil. Higher first-order reaction constants for orchard than tilled soil are in line with both higher total porosity and contribution of biological pores in the former. The first-order reaction constants for the leaching of chemical compounds enable the prediction of the actual compound concentration and the interactions between compound and soil as affected by management system. The study demonstrates the effectiveness of simultaneous chemical and physical analyses as a tool for the understanding of leaching in variously managed soils.