Effects of compost stability on plant growth, microbiological parameters and nitrogen availability in media containing mixed garden-waste compost

1995 ◽  
Vol 54 (3) ◽  
pp. 279-284 ◽  
Author(s):  
Alan A. Keeling ◽  
Bryan S. Griffiths ◽  
Karl Ritz ◽  
Mike Myers
Keyword(s):  
Plant Growth ◽  
Nitrogen Availability ◽  
Compost Stability ◽  
Microbiological Parameters ◽  
Garden Waste

Physiological Responses of Amaranthus Cruentus L. to Drought Stress Under Sufficient- and Deficient-Nitrogen Conditions

2021 ◽  
Author(s):  
Inês Cechin ◽  
Laura Prado da Silva ◽  
Elisa Teófilo Ferreira ◽  
Sarah Corrêa Barrochelo ◽  
Fernanda Pereira de Souza Rosa de Melo ◽  
...  
Keyword(s):  
Water Stress ◽  
Plant Growth ◽  
Photosynthetic Pigments ◽  
Dry Matter ◽  
Nitrogen Availability ◽  
Leaf Nitrogen ◽  
Nitrogen Supply ◽  
Plant Performance ◽  
In Planta ◽  
Phenolic Contents

Abstract Water and nitrogen availability are environmental factors that can impair plant growth, and when they are combined their effects can be intensified or reduced. The objective of this study was to analyse the influence of nitrogen availability on the responses of Amaranthus cruentus’s metabolisms to water stress. The plants were cultivated in plastic pots filled with vermiculite and kept under greenhouse conditions and were watered with 70% of full strength nitrogen-free Long Ashton solution, containing 1.97 or 9.88 kg N ha−1 as ammonium nitrate, three times a week. Photosynthetic parameter were evaluated in planta and leaves were harvested for chemical analysis of proline and phenolic contents. Higher nitrogen supply increased the shoot dry matter, photosynthetic pigments, photosynthesis, stomatal conductance, transpiration, total leaf nitrogen, proline, nitrate and ammonium but reduced the concentration of flavonoids and total phenols. Water stress for 6 days did not affect dry matter, photosynthetic pigments, leaf nitrogen, ammonium or specialized metabolites but increased the proline and affected negatively the other variables. The observed interactions between nitrogen and water supply resulted in no alleviation of the negative effects of drought on amaranth. Although the increase in nitrogen supply had benefits on plant performance, it intensified the negative effect of water stress. The study shows the importance of choosing the correct level of nitrogen fertilization in order to obtain satisfactory results in terms of plant growth under drought conditions.

scholarly journals Evaluation of the Agronomic Performance of Organic Processing Tomato as Affected by Different Cover Crop Residues Management

Agronomy ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 504 ◽  
Author(s):  
Abou Chehade ◽  
Antichi ◽  
Martelloni ◽  
Frasconi ◽  
Sbrana ◽  
...  
Keyword(s):  
Plant Growth ◽  
Cover Crop ◽  
Nitrogen Availability ◽  
Crop Residues ◽  
N Uptake ◽  
Total Yield ◽  
Soluble Solids ◽  
Plastic Mulch ◽  
Processing Tomato ◽  
No Till

No-till practices reduce soil erosion, conserve soil organic carbon, and enhance soil fertility. Yet, many factors could limit their adoption in organic farming. The present study investigated the effects of tillage and cover cropping on weed biomass, plant growth, yield, and fruit quality of an organic processing tomato (Solanum lycopersicon L. var. Elba F1) over two seasons (2015–2017). We compared systems where processing tomato was transplanted on i) tilled soil following or not a winter cover crop (Trifolium squarrosum L.) and with/without a biodegradable plastic mulch; and ii) no-till where clover was used, after rolling and flaming, as dead mulch. Tomato in no-till suffered from high weed competition and low soil nitrogen availability leading to lower plant growth, N uptake, and yield components with respect to tilled systems. The total yield in no-till declined to 6.8 and 18.3 t ha−1 in 2016 and 2017, respectively, with at least a 65% decrease compared to tilled clover-based systems. No evidence of growth-limiting soil compaction was noticed but a slightly higher soil resistance was in the no-till topsoil. Tillage and cover crop residues did not significantly change tomato quality (pH, total soluble solids, firmness). The incorporation of clover as green manure was generally more advantageous over no-till. This was partly due to the low performance of the cover crop where improvement may limit the obstacles (i.e., N supply and weed infestation) and enable the implementation of no-till in organic vegetable systems.

Effects of wild rice (Zizania palustris) straw on biomass and seed production in northern Minnesota

2006 ◽  
Vol 84 (6) ◽  
pp. 1019-1024 ◽  
Author(s):  
Rachel Durkee Walker ◽  
John Pastor ◽  
Bradley W. Dewey
Keyword(s):  
Plant Growth ◽  
Wild Rice ◽  
Nitrogen Availability ◽  
Plant Root ◽  
Nitrogen Immobilization ◽  
Potential Growth ◽  
Available N ◽  
Zizania Palustris ◽  
Seed Biomass ◽  
Total Plant

Wild rice ( Zizania palustris L.) litter accumulation may inhibit plant growth and production both by physically suppressing seedling emergence and by nitrogen immobilization in fresh litter. This latter mechanism could reduce nitrogen availability to plants early in the growing season at a period when more than half of the annual uptake occurs. To test the importance of these mechanisms, we planted wild rice in mesocosms. Half the tanks were planted with seeds sown below the litter and half were planted with seedlings grown to a height taller than litter thickness. One-third of the tanks were treated with fresh (nitrogen immobilizing) litter, one-third were treated with litter that had been incubated for 26 d and was mineralizing nitrogen, and one-third did not receive litter. These treatments resulted in a fully crossed factorial design, with nine replicates for each treatment combination, totaling 54 tanks. We measured plant growth, vegetative, root, and seed biomass, total plant N, and available N at 2.5 cm sediment depth. The presence of litter and its stage of decay caused plant, root, and seed biomass, and seed and total plant nitrogen content to increase. We found no physical inhibition of litter on the potential growth of plants started as seeds. Therefore, the timing of litter nitrogen immobilization or mineralization affects the potential growth of wild rice.

scholarly journals Seasonal Growth and Nitrogen Uptake of Encore Azalea ‘Chiffon’ Affected by Nitrogen Availability and Containers

HortScience ◽  
2019 ◽  
Vol 54 (5) ◽  
pp. 948-954
Author(s):  
Tongyin Li ◽  
Guihong Bi ◽  
Richard L. Harkess
Keyword(s):  
Plant Growth ◽  
Nitrogen Availability ◽  
N Uptake ◽  
Dry Weight ◽  
Recycled Paper ◽  
Active Growth ◽  
N Content ◽  
Plastic Containers ◽  
Spad Readings ◽  
Container Type

Plant growth and nitrogen (N) uptake of Encore® azalea ‘Chiffon’ (Rhododendron sp.) grown in a traditional plastic container or a biodegradable container made from recycled paper were investigated over the 2013 growing season. Three hundred twenty 1-year-old azalea liners, grown in two types of containers, were fertilized twice weekly with 250 mL N-free liquid fertilizer with no N or 15 mm N from ammonium nitrate (NH4NO3). Biweekly from 10 May to 3 Dec., five plants from each N rate and container type were selected randomly to measure plant height, widths, and leaf chlorophyll content in terms of soil–plant analysis development (SPAD) readings, and were then harvested destructively for nutrient analyses. Leaf SPAD readings and tissue N concentration were influenced mostly by N rate rather than container type, with 15 mm N producing greater values than the no-N treatment. Leaf SPAD readings increased from May to August and decreased from September to December. Using 15 mm N, plastic containers generally resulted in similar or increased plant growth [plant growth index (PGI) and dry weight] and N uptake from May to August as in biocontainers, with greater SPAD readings, leaf and root dry weights, stem and root N concentrations, and leaf and root N content than biocontainers at some harvests. However, biocontainers resulted in greater PGI, dry weights, and N content (in leaves, stems, roots, and total plant) than plastic containers later in the season, from September to December. These differences appeared in September after plants grown in plastic containers ceased active growth in dry weight and N uptake by the end of August. Plants grown in biocontainers had extended active growth from 13 Sept. to 9 Nov., resulting in greater tissue N content and greater N uptake efficiency. The biocontainers used in this study produced azalea plants of greater size, dry weight, and improved N uptake by increasing growth rate and extending the plants’ active growth period into late fall. The beneficial effects likely resulted from greater evaporative cooling through container sidewalls and the lighter color of the biocontainers, and therefore led to lower substrate temperatures and improved drainage.

scholarly journals Controls of terrestrial ecosystem nitrogen loss on simulated productivity responses to elevated CO<sub>2</sub>

2018 ◽  
Vol 15 (18) ◽  
pp. 5677-5698 ◽  
Author(s):  
Johannes Meyerholt ◽  
Sönke Zaehle
Keyword(s):  
Plant Growth ◽  
Elevated Co2 ◽  
Large Scale ◽  
Nitrogen Availability ◽  
Carbon Sink ◽  
Nitrogen Loss ◽  
Terrestrial Ecosystem ◽  
Turnover Rates ◽  
Terrestrial Biosphere ◽  
Loss Rates

Abstract. The availability of nitrogen is one of the primary controls on plant growth. Terrestrial ecosystem nitrogen availability is not only determined by inputs from fixation, deposition, or weathering, but is also regulated by the rates with which nitrogen is lost through various pathways. Estimates of large-scale nitrogen loss rates have been associated with considerable uncertainty, as process rates and controlling factors of the different loss pathways have been difficult to characterize in the field. Therefore, the nitrogen loss representations in terrestrial biosphere models vary substantially, adding to nitrogen cycle-related uncertainty and resulting in varying predictions of how the biospheric carbon sink will evolve under future scenarios of elevated atmospheric CO2. Here, we test three commonly applied approaches to represent ecosystem-level nitrogen loss in a common carbon–nitrogen terrestrial biosphere model with respect to their impact on projections of the effect of elevated CO2. We find that despite differences in predicted responses of nitrogen loss rates to elevated CO2 and climate forcing, the variety of nitrogen loss representation between models only leads to small variety in carbon sink predictions. The nitrogen loss responses are particularly uncertain in the boreal and tropical regions, where plant growth is strongly nitrogen-limited or nitrogen turnover rates are usually high, respectively. This highlights the need for better representation of nitrogen loss fluxes through global measurements to inform models.

Nitrogen fixation makes biomass allocation to roots independent of soil nitrogen supply

2007 ◽  
Vol 85 (9) ◽  
pp. 787-793 ◽  
Author(s):  
John H. Markham ◽  
Corinthe Zekveld
Keyword(s):  
Nitrogen Fixation ◽  
Plant Growth ◽  
Biomass Allocation ◽  
Soil Nitrogen ◽  
Nitrogen Availability ◽  
Nitrogen Concentration ◽  
Nitrogen Fixing ◽  
Soil Nitrogen Availability ◽  
Least Squares Fit ◽  
Allocation Patterns

Biomass allocation patterns in plants are known to be affected by soil nitrogen availability. Since nitrogen availability can depress symbiotic nitrogen fixation, and nitrogen fixation can make plant growth independent of soil nitrogen availability but is energetically costly, it is unclear how allocation patterns in nitrogen-fixing species should respond to variation in soil nitrogen availability. We examined the effect of nitrogen source and concentration on the growth and allocation patterns in the nitrogen-fixing shrub Alnus viridis subsp. crispa (Aiton) Turrill. Plants were grown with either NH4+-N or NO3–-N at a range of low N concentrations, from 0 to 2 mmol·L–1, and either inoculated with Frankia or not. Plants without nodules had 25.l% lower biomass and had double the allocation to roots at all but the 2 mmol·L–1 nitrogen concentration. Even though nodulated plants increased growth with nitrogen concentration, allocation to roots as a fraction of total biomass did not vary in these plants, suggesting increased growth resulted from more efficient nitrogen acquisition. Allocation to roots was a significant predictor of plant growth in non-nodulated plants (r2 = 0.318, for linear least squares fit with log mass) but not for nodulated plants (r2 = 0.108). As nitrogen concentrations increased, allocation to nodules, specific nodule numbers, and the proportion of nitrogen fixed by the plants decreased, demonstrating a shift to soil nitrogen use.

A quantitative top-down view of interactions between stresses: theory and analysis of nitrogen - water co-limitation in Mediterranean agro-ecosystems

2005 ◽  
Vol 56 (11) ◽  
pp. 1151 ◽  
Author(s):  
Victor O. Sadras
Keyword(s):  
Plant Growth ◽  
Grain Yield ◽  
Water Use Efficiency ◽  
Water Use ◽  
Nitrogen Availability ◽  
Growth And Yield ◽  
Top Down ◽  
Trade Offs ◽  
Eastern Australia ◽  
Use Efficiency

The multiple factors constraining the growth, reproduction, and survival of diverse organisms are often non-additive. Research of interacting factors generally involves conceptual models that are specific for target organism, type of stress, and process. As a complement to this reductionist, bottom-up view, in this review I discuss a quantitative top-down approach to interacting stresses based on co-limitation theory. Firstly, co-limitation theory is revised. Co-limitation is operationally identified when the output response of a biological system (e.g. plant or population growth) to two or more inputs is greater than its response to each factor in isolation. The hypothesis of Bloom, Chapin, and Mooney, that plant growth is maximised when it is equally limited by all resources, is reworded in terms of co-limitation and formulated in quantitative terms, i.e. for a given intensity of aggregate stress, plant growth is proportional to degree of resource co-limitation. Emphasis is placed on the problems associated with the quantification of co-limitation. It is proposed that seasonal indices of nitrogen and water stress calculated with crop simulation models can be integrated in indices accounting for the aggregated intensity of water and nitrogen stress (SWN), the degree of water and nitrogen co-limitation (CWN), and the integrated effect of stress and co-limitation (SCWN = CWN/SWN). The expectation is that plant growth and yield should be an inverse function of stress intensity and a direct function of co-limitation, thus proportional to SCWN. Secondly, the constraints imposed by water and nitrogen availability on yield and water use efficiency of wheat crops are highlighted in case studies of low-input farming systems of south-eastern Australia. Thirdly, the concept of co-limitation is applied to the analysis of (i) grain yield responses to water–nitrogen interactions, and (ii) trade-offs between nitrogen- and water-use efficiency. In agreement with theoretical expectations, measured grain yield is found to be proportional to modelled SCWN. Productivity gains associated with intensification of cropping practices are interpreted in terms of a trade-off, whereby water-use efficiency is improved at the expense of nitrogen-use efficiency, thus leading to a higher degree of resource co-limitation.

Sign in / Sign up

Export Citation Format

Share Document