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Czaban, W.

Publications and source records attributed to Czaban, W..

4 recordsLinked to original sources

Five seasons with DeepRootLab: A unique facility for easier deep root research in the field

Deep-rooted crops accessing water and nutrients from deep soil layers enhance the resource base for crop production. However, studying these roots in field conditions is labor-intensive, limiting research scope. We established a field root research facility with 48 plots for replicated experiments. The facility includes 144 six-meter-long minirhizotron tubes and an AI-based pipeline for rapid root trait analysis. We also attempted to install access-tubes and customized ingrowth-core production for less-invasive root activity determination. Our study revealed significant differences in deep root density among species, particularly at depths of 2.5 to 4.5 meters, over five years. The less invasive studies using ingrowth-cores reached depths of 4.2 meters. Nutrient tracer 15N analysis showed marked differences in deep root activity among crop species. TDR sensors indicated varying water depletion in deeper soil layers, influenced by crop species and root growth patterns. We established a field facility for studying deep root growth and function, demonstrating its effectiveness in analyzing diverse deep-rooted plant species. This facility provides an ideal platform for conducting meaningful research in deep soil layers, yielding statistically and biologically significant results for agricultural applications.

plant biology↗

Exploitation of neighbouring subsoil for nutrient acquisition under annual-perennial strip intercropping systems

Little is known of how the deep root systems of perennial crops contribute to deeper and better resource use when intercropped with annuals in arable fields. Therefore, we aimed at measuring the capacity of perennial deep roots, alfalfa (Medicago sativa L.) and curly dock (Rumex crispus L.) to access the nutrient source located under the neighboring annuals at 1.0 and 2.5 m of soil depth. Alfalfa and curly dock were able to access the tracer-labelled source placed at a distance under the annual crop strips. As a result, the reliance on deeper soil layer for nutrient uptake under intercroppings became greater compared with sole-croppings. Combination of an annual cereal (winter rye) and a perennial legume (alfalfa) with contrasting root systems exhibited higher resource complementarity compared with intercroppings having similar root systems or absence of legumes. Our results demonstrated that the deep-rooted perennials when intercropped with annuals can induce vertical niche complementarity, especially at deeper soil layers. This was assumed to be due to the vertically stratified root activity between the crop components, however, the magnitude of the effects depended on choice of crop combinations, and on types of tracers. Future studies should include estimates such as relative yield total and land equivalent ratio to quantitatively determine the effects of resource acquisition under annual-perennial intercropping in arable fields.

plant biology↗

Co-occurrence of organic and inorganic N sources influences asparagine uptake and internal amino acid profiles in white clover

Direct plant uptake of organic nitrogen (N) is important for plant N nutrition, but we lack knowledge of how the concentration of external N forms (organic and inorganic) -influence organic N uptake and plant N status. We investigated the uptake of the amino acid asparagine (Asn) in white clover in the presence of different nitrate (NO3-), Asn, and total N concentrations. White clover seedlings were for one week exposed to combinations of NO3- (3-30 {micro}mol N kg-1 sand DW) and Asn (3-30 {micro}mol N kg-1 sand DW), where after the Asn uptake rate was determined by addition of 13C4-Asn. Shoot and root Asn content and amino acid profiles were also analyzed. Increasing external NO3- and total N concentrations decreased 13C4-Asn uptake rates and internal clover Asn content. Furthermore, total N affected clover amino acid profiles from non-essential amino acids at low N doses to the dominance of essential amino acids at increasing N doses. Asn uptake rate in white clover is reduced by increasing inorganic N, but not by increasing organic N concentrations. Furthermore, plant amino acid profiles are likely to be a more sensitive indicator of N supply and descriptor of the N status.

plant biology↗

Mouse model of the human serotonin transporter-linked polymorphic region

Genetic factors play a significant role in risk for mood and anxiety disorders. Polymorphisms in genes that regulate the brain monoamine systems, such as catabolic enzymes and transporters, are attractive candidates for being risk factors for emotional disorders given the weight of evidence implicating monoamines involvement in these conditions. Several common genetic variants have been identified in the human serotonin transporter (5-HTT) gene, including a repetitive sequence located in the promoter region of the locus called the serotonin transporter-linked polymorphic region (5-HTT-LPR). This polymorphism has been associated with a number of mental traits in both humans and primates, including depression, neuroticism, and harm avoidance. Some, but not all studies found a link between the polymorphism and 5-HTT levels, leaving open the question of whether the polymorphism affects risk for mental traits via changes in 5-HTT expression. To investigate the impact of the polymorphism on gene expression, serotonin homeostasis, and behavioural traits we set out to develop a mouse model of the human 5-HTT- LPR. Here we describe the creation and characterization of a set of mouse lines with single copy human transgenes carrying the short and long 5-HTT-LPR variants.

neuroscience↗