Is phytotoxicity of Phragmites australis residue influenced by decomposition condition, time and density?

2014 ◽  
Vol 65 (6) ◽  
pp. 505 ◽  
Author(s):  
Md. N. Uddin ◽  
Randall W. Robinson ◽  
Domenic Caridi ◽  
Md. A. Y. Harun
Keyword(s):  
Phragmites Australis ◽  
Wetland Management ◽  
Water Soluble ◽  
Anaerobic Conditions ◽  
Soil Extracts ◽  
Soluble Phenolics ◽  
Physicochemical Variables ◽  
Residue Decomposition ◽  
Germination And Growth ◽  
Over Time

Phragmites australis is an invasive wetland plant and allelopathy appears to contribute to its invasiveness. We studied dynamics of physicochemical characteristics and phytotoxicity through residue decomposition of Phragmites with and without soil under different conditions and density over time. Physicochemical variables (water-soluble phenolics, dissolved organic carbon, specific ultraviolet absorbance, pH, electrical conductivity, osmotic potential and some anions, namely PO43–, Cl–, NO2–, NO3– and SO42–) of extracts were more consistent and showed normal range in aerobic rather than anaerobic conditions. ‘Residue alone’ and ‘residue with soil’ extracts exhibited significant inhibition on germination and growth of Poa labillardierei and Lactuca sativa initially but reduced over time in aerobic conditions whereas the inhibition increased sharply and remained almost stable in anaerobic conditions (P ≤ 0.001). Regression analyses showed that water-soluble phenolics were a significant predictor of the inhibitory effects on germination and growth of tested species compared with other variables in the extracts. Long-term decomposed residues exhibited significant effects on germination and growth of Melaleuca ericifolia (P ≤ 0.01) depending on residue density in soil. The results demonstrated that decomposition condition and soil incorporation coupled with residue density may play a crucial role over time in dynamics of physicochemical variables and associated phytotoxicity. The study contributes to understanding of the ecological consequences of phytotoxins in residue decomposition, partially explaining the invasion process of Phragmites in wetlands and thereby improving wetland management.

Phytotoxic evaluation of Phragmites australis: an investigation of aqueous extracts of different organs

2012 ◽  
Vol 63 (9) ◽  
pp. 777 ◽  
Author(s):  
Md N. Uddin ◽  
Domenico Caridi ◽  
Randall W. Robinson
Keyword(s):  
Phragmites Australis ◽  
Invasive Plants ◽  
Aerobic Condition ◽  
Water Soluble ◽  
Aqueous Extracts ◽  
Soluble Phenolics ◽  
Leaf Leachate ◽  
Allelopathic Interference ◽  
The Stability ◽  
Germination Bioassays

Phragmites australis is one of the most widespread and invasive plants on earth. Allelopathic interference has been considered as a possible way associated with its invasiveness in wetlands. A series of ecologically realistic experiments was conducted to explore allelochemical phytotoxicity of Phragmites. Germination bioassays using aqueous extracts of different organs (leaf, stem, root and rhizome) of Phragmites were tested with model seeds (Lactuca sativa and Raphanus sativus) and associated plant species (Juncus pallidus and Rumex conglomeratus). These studies showed that leaf and rhizome extracts exhibited strong inhibition on germination, biometric and physiological parameters (all P ≤ 0.001). Dose–response studies confirmed LC50 (4.68% and 11.25%) of Lactuca for leaf and rhizome extracts respectively. Root growth of Juncus and Rumex was inhibited by 75% and 30%, respectively, in leaf leachate-incorporated soil. Chlorophyll content and maximum quantum yield (Fv/Fm) were significantly reduced with leaf and rhizome leachates. The stability and quantity of water-soluble phenolics in anaerobic versus aerobic condition may influence phytotoxic effects to other species. Phragmites organs can be ranked in order of allelopathic potentiality as follows: leaf > rhizome > root > stem. The present study highlighted the potential impacts of allelochemicals on plant recruitment in wetlands invaded by Phragmites.

A time-series effect of phytase supplementation on phosphorus utilization in growing and finishing pigs fed a low-phosphorus diet

2021 ◽  
Vol 100 (1) ◽  
Author(s):  
Olufemi Oluwaseun Babatunde ◽  
Olayiwola Adeola
Keyword(s):  
Time Series ◽  
Growth Performance ◽  
Block Design ◽  
Average Daily Gain ◽  
Plasma Concentrations ◽  
Growing Pigs ◽  
Water Soluble ◽  
Feed Ratio ◽  
Finishing Pigs ◽  
Over Time

Abstract Two experiments were carried out to determine a time-series effect of phytase on phosphorus (P) utilization in growing and finishing pigs using growth performance, apparent total tract digestibility (ATTD) of nutrients, P excretion, and plasma concentrations of minerals as the response criteria for evaluation. In both experiments, treatments were arranged as a 3 × 4 factorial in a randomized complete block design with 3 corn–soybean meal-based diets including a P-adequate positive control (PC), a low-P negative control (NC; no inorganic P), and NC supplemented with phytase at 1,000 FYT/kg (NC + 1,000); and 4 sampling time points at days 7, 14, 21, and 28 in experiment 1, and days 14, 26, 42, and 55 in experiment 2. In both trials, 96 growing pigs with average body weight (BW) of 19.8 ± 1.16 and 49.8 ± 3.21 kg, respectively, were allocated to the 3 diets with 8 replicates pens (4 barrows and 4 gilts) and 4 pigs per pen. In experiment 1, pigs fed the PC had higher (P < 0.01) BW, average daily gain (ADG), average daily feed intake (ADFI), and gain-to-feed ratio (G:F) when compared with pigs fed the NC. There was an interaction (P < 0.01) between time and diet on the BW and ADG of pigs while a linear and quadratic increase (P < 0.01) was observed with the ADFI and G:F, respectively, over time. Phytase supplementation improved (P < 0.01) all growth performance responses. Pigs fed the PC had greater (P < 0.01) ATTD of P and Ca than pigs fed the NC. There was no interaction effect on the ATTD of nutrients. Phytase addition improved the ATTD of P and Ca over pigs fed the NC. There was an interaction (P < 0.01) between diet and time on the total and water-soluble P (WSP) excreted. There was a quadratic decrease (P < 0.01) in plasma concentration of Ca in pigs over time. In experiment 2, there was a quadratic increase (P < 0.01) in BW, ADG, and G:F of pigs over time. Similarly, the inclusion of phytase improved (P < 0.05) all growth performance parameters except ADFI. A linear increase (P < 0.05) in the ATTD of DM, P, and Ca occurred over time. Phytase inclusion improved (P < 0.01) the ATTD of P and Ca. Plasma concentrations of P were improved by phytase addition. Phytase supplementation of the NC reduced WSP excretion by 45%, 32%, and 35% over the growing, finishing, and entire grow-finish period, respectively. In conclusion, phytase improves the utilization of P in growing and finishing pigs; however, the magnitude of effect on responses may vary over time.

A new water-soluble bacterial NADH: fumarate oxidoreductase

2020 ◽  
Vol 367 (20) ◽  
Author(s):  
Yulia V Bertsova ◽  
Ilya P Oleynikov ◽  
Alexander V Bogachev
Keyword(s):  
Nadh Dehydrogenase ◽  
Reductase Activity ◽  
Domain Architecture ◽  
Water Soluble ◽  
Fumarate Reductase ◽  
Anaerobic Conditions ◽  
New Type ◽  
Prosthetic Groups ◽  
Low Rate ◽  
Covalently Bound

ABSTRACT The cytoplasmic fumarate reductase of Klebsiella pneumoniae (FRD) is a monomeric protein which contains three prosthetic groups: noncovalently bound FMN and FAD plus a covalently bound FMN. In the present work, NADH is revealed to be an inherent electron donor for this enzyme. We found that the fumarate reductase activity of FRD significantly exceeds its NADH dehydrogenase activity. During the catalysis of NADH:fumarate oxidoreductase reaction, FRD turnover is limited by a very low rate (∼10/s) of electron transfer between the noncovalently and covalently bound FMN moieties. Induction of FRD synthesis in K. pneumoniae cells was observed only under anaerobic conditions in the presence of fumarate or malate. Enzymes with the FRD-like domain architecture are widely distributed among various bacteria and apparently comprise a new type of water-soluble NADH:fumarate oxidoreductases.

THE INFLUENCE OF THE EXTRACT OF SOME CROPS AND SOIL RESIDUES ON GERMINATION AND GROWTH

1960 ◽  
Vol 40 (1) ◽  
pp. 188-197 ◽  
Author(s):  
K. F. Nielsen ◽  
W. B. Woods ◽  
T. F. Cuddy
Keyword(s):  
Seed Germination ◽  
Root Length ◽  
Deionized Water ◽  
The Other ◽  
Percentage Germination ◽  
Soil Extracts ◽  
Field Crops ◽  
Time Required ◽  
Germination And Growth ◽  
Germinated Seeds

Six plant species were germinated in sand wetted with water extracts of tissues of five field crops and three soils. Deionized water was used as a check f he study was conducted using standard seed germination techniques.Alter 7 to 10 days all of the germinated seeds were harvested and measurements made of the shoot and root lengths.Alfalfa extract caused the greatest reduction in shoot and root length as well as m percentage germination. It caused the greatest increase in the time required for germination. Timothy extract was not quite as harmful as the alfalfa. Extracts of oats, corn and potatoes were still less harmful with potato extract causing the least effect.The soil extracts generally had very little effect when compared with deionized water.Plant species showed marked differences in tolerance to the extracts alfalfa being the most resistant and timothy the least.Where water alone was used rate of germination and per cent germination were as high or higher than with the other extracts, but the root and shoot lengths were not always the greatest.

scholarly journals Phytotoxic Effect of Tithonia rotundifolia (Miller) S.F.Blake on Chlorophyll and Protein Contents of Vigna unguiculata L. and Zea mays L.

2019 ◽  
Vol 10 (2) ◽  
pp. 79
Author(s):  
Ilori Olasupo John ◽  
Olutobi Oluwafunmilayo Otusanya
Keyword(s):  
Zea Mays ◽  
Vigna Unguiculata ◽  
Zea Mays L ◽  
Water Soluble ◽  
Inhibitory Effects ◽  
Potted Plants ◽  
Phytotoxic Effect ◽  
Biochemical Analyses ◽  
Germination And Growth ◽  
Range Test

A large number of plants impose inhibitory effects on the germination and growth of neighbouring or successional plants by releasing allelochemicals into the soil. This study investigated the phytotoxic effects of Tithonia rotundifolia (Miller) S.F.Blake on the chlorophyll and protein contents of Vigna unguiculata (L.) Walpers and Zea mays L.. This was with a view to determining the susceptibility of these crops to allelochemicals in the extracts prepared from T. rotundifolia. Seeds of the test plants were sown in pots filled with top humus soil. At two weeks, seedlings in each pot were thinned down to 10 seedlings per pot. Potted plants of the test crops were supplied with 400 ml of the appropriate water extracts while the control potted plants were supplied with 400 ml of water. Biochemical analyses were carried out according to standard methods. The data obtained were analysed by (ANOVA) to determine significant (P< 0.05) effects. The means were compared using Duncan Multiple Range Test. The chlorophyll a, chlorophyll b, total chlorophyll and protein contents in V. unguiculata and Z. mays and were significantly inhibited by the extract from T. rotundifolia. The inhibitory effects of these allelochemicals increased with concentration. The phytotoxic effect of T. rotundifolia was species dependent. It was concluded that the extract contains water-soluble allelochemicals which inhibited the biochemical parameters of the test crops. T. rotundifolia should be controlled where it grows in association with cultivated crops.

scholarly journals Soil Type and Wetness Affect Tint of Peanut (Arachis hypogaea L.) Pod Shell

2010 ◽  
Vol 37 (2) ◽  
pp. 144-150 ◽  
Author(s):  
I. Ginzberg ◽  
A. Tubi ◽  
O. Buchshtab ◽  
S. Wininger ◽  
B. Ben-Dor ◽  
...  
Keyword(s):  
Arachis Hypogaea ◽  
Water Soluble ◽  
Shell Color ◽  
Development Zone ◽  
Soil Extracts ◽  
Bright Yellow ◽  
Arachis Hypogaea L ◽  
Overhead Irrigation ◽  
Pod Development ◽  
Soil Wetness

Abstract Peanut (Arachis hypogaea L.) is a globally important legume crop that is utilized fresh, roasted, or pressed for oil products. A substantial market exists for in-shell peanuts, and shell color is an important factor affecting price — consumers favor bright yellow. Field observations have indicated that the type of soil in which the peanut pods develop can affect shell color and tint. Field and greenhouse experiments in which plants were grown in sandy soil while pods were allowed to develop in various tested soils verified this primary observation: sandy soils resulted in bright-yellow shells, dark soils (such as peat) resulted in a darker shell color, while loess soils resulted in intermediate shell colors. Incubation of peanut pods in saturated soil solutions or filtered soil extracts inferred the existence of two opposing processes that may affect shell color: adherence of water-soluble soil components to the shell surface, and the washing-off of shell material from this surface. Overhead irrigation with a reduced amount of water or watering with a subsurface drip system concealed at a depth of 25 cm resulted in brighter shell colors than applying the normal amount of water by overhead irrigation. These data suggest that reducing soil wetness in the pod-development zone may increase shell brightness. Field experiments also indicating that final shell color is determined towards the end of pod development, suggesting that soil wetness in the pod-development zone should be controlled during at least the last 4 weeks of growth, to maintain a low level of wetness.

The nature of interference potential of Kalmiaangustifolia

1996 ◽  
Vol 26 (11) ◽  
pp. 1899-1904 ◽  
Author(s):  
Inderjit Inderjit ◽  
A.U. Mallik
Keyword(s):  
Leaf Litter ◽  
Black Spruce ◽  
Organic Soil ◽  
Water Soluble ◽  
Total Phenolic ◽  
Organic Soils ◽  
Soluble Phenolics ◽  
Phenolic Contents ◽  
Mineral Soils ◽  
Rule Out

The nature of interference potential of Kalmiaangustifolia L., a boreal forest understorey shrub, was investigated in laboratory experiments. Organic and mineral soils, not previously associated with Kalmia, were amended with different quantities of its leaf litter and leaf litter leachates. The objectives of the study were (i) to determine changes in soil chemistry after amending with Kalmia and (ii) to determine the effect of amendment on growth of black spruce (Piceamariana (Mill.) BSP) seedlings. All soils were analyzed for pH, organic matter, PO4−, N, Ba, Cu, Zn, Fe, Mn, Ca, Na, K, Mg, Al, and total phenolics. Chemical characteristics of both organic and mineral soils were significantly changed. Water-soluble phenolics in one of the amended organic soils were significantly higher than in unamended organic soil. However, all of the amended mineral soils had significantly higher total phenolic contents than unamended control soils. A linear decrease in N content was observed in amended organic and mineral soils with increasing quantities of Kalmia leaf litter. Amended mineral soils had higher concentrations of Fe, Mn, Al, and PO4− than the control. We relate higher accumulations of PO4−, Fe, Mn, and Al in amended mineral soils to higher soil phenolic contents. Amendment of organic and mineral soils significantly reduced the root and shoot growth of black spruce. This study demonstrates that Kalmia has potential for nutrient interference and does not rule out allelopathic effects of Kalmia to black spruce seedling growth.

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