Chemical ecology of Eragrostis plana helps understanding of the species’ invasiveness in an agroecosystem community

2018 ◽  
Vol 69 (10) ◽  
pp. 1050
Author(s):  
Henrique von Hertwig Bittencourt ◽  
Michelangelo Muzell Trezzi ◽  
Sirlei Dias Teixeira ◽  
Lisandro da Silva Bonome ◽  
Aline Garcias de Vargas ◽  
...  

South African lovegrass (Eragrostis plana Nees) is an aggressive and difficult-to-control species in grazing areas of the south of South America, whose invasion capacity is increased by its phytotoxic capability. The objectives of this work were to identify and quantify chemicals produced by the plant shoots, to evaluate the inhibitory capability of plant extracts on development of lucerne (Medicago sativa L.) and wheat (Triticum aestivum L.), and to determine the spatial distribution of phenolics in rhizosphere soil in an infested field. Extracts were obtained by exhaustive extraction of dry shoot biomass, using solvents in increasing order of polarity. Soil samples contained in the rhizosphere were collected from an infested field. Bioassays for determination of phytotoxicity of extracts on lucerne and wheat seedlings were conducted in a completely randomised design with four replicates. The extracts showed suppressive, stimulating or neutral effects on the development of the radicle, shoots, and total lucerne and wheat seedlings, with greater phytotoxicity, generally, of ethyl acetate and methyl alcohol extracts. In the shoot extracts, nine phenolic compounds were identified and quantified: caffeic acid, coumaric acid, ferulic acid, gallic acid, vanillic acid, catechin, epicatechin, resveratrol, rutin. Of these, four were identified in the soil: catechin, epicatechin, coumaric acid, ferulic acid. Catechin, epicatechin and ferulic acid showed similar distribution patterns in the soil profile, with higher concentrations detected on the surface and on the side opposite the plant crown, which indicates release by the decomposition of tissues deposited on the soil surface. Coumaric acid showed higher concentrations on the surface and in the deeper layer of the soil next to the plant, indicating release both from decomposition of the shoots and from the root system. Future work may explore the phytotoxicity of the analytes identified, either isolated or in admixture, using dose curves and an inhibitory response to target plant species.

1985 ◽  
Vol 65 (1) ◽  
pp. 151-161
Author(s):  
M. C. HEATH ◽  
R. B. McKERCHER ◽  
R. ASHFORD

The combination of high soil temperature (36 °C) with trifluralin caused spring wheat (Triticum aestivum L. ’Neepawa’) seedlings to have shortened coleoptiles that failed to emerge above the soil surface. This resulted in damaged primary leaves due to abrasion in the soil layers. Evidence is presented that rapeseed (Brassica napus L. ’Regent’) residues have phytotoxic effects on wheat seedlings. High soil ammonium ion concentrations did not affect trifluralin phytotoxicity. All results indicated that the potentially damaging effects of high soil temperature and rapeseed residue are independent of, but additive to, those of trifluralin.Key words: Temperature, ammonium ion, rapeseed, trifluralin, wheat


Biomics ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 329-336
Author(s):  
A.R. Lubyanova ◽  
F.M. Shakirova ◽  
M.V. Bezrukova

We studied the immunohistochemical localization of abscisic acid (ABA), wheat germ agglutinin (WGA) and dehydrins in the roots of wheat seedlings (Triticum aestivum L.) during 24-epibrassinolide-pretreatment (EB-pretreatment) and PEG-induced dehydration. It was found coimmunolocalization of ABA, WGA and dehydrins in the cells of central cylinder of basal part untreated and EB-pretreated roots of wheat seedlings under normal conditions and under osmotic stress. Such mutual localization ABA and protective proteins, WGA and dehydrins, indicates the possible effect of their distribution in the tissues of EB-pretreated wheat roots during dehydration on the apoplastic barrier functioning, which apparently contributes to decrease the water loss under dehydration. Perhaps, the significant localization of ABA and wheat lectin in the metaxylem region enhances EB-induced transport of ABA and WGA from roots to shoots under stress. It can be assumed that brassinosteroids can serve as intermediates in the realization of the protective effect of WGA and wheat dehydrins during water deficit.


Botany ◽  
2018 ◽  
Vol 96 (3) ◽  
pp. 175-186 ◽  
Author(s):  
Kwang-Yeol Yang ◽  
Stephanie Doxey ◽  
Joan E. McLean ◽  
David Britt ◽  
Andre Watson ◽  
...  

Formulations that include nanoparticles of CuO and ZnO are being considered for agricultural applications as fertilizers because they act as sources of Cu or Zn. Currently, few studies of the effects of these nanoparticles (NPs) consider the three-way interactions of NPs with the plant plus its microbiome. At doses that produced root shortening by both nanoparticles (NPs), CuO NPs induced the proliferation of elongated root hairs close to the root tip, and ZnO NPs increased lateral root formation in wheat seedlings (Triticum aestivum L.). These responses occurred with roots colonized by a beneficial bacterium, Pseudomonas chlororaphis O6 (PcO6), originally isolated from roots of wheat grown under dryland farming in calcareous soils. The PcO6-induced tolerance to drought stress in wheat seedlings was not impaired by the NPs. Rather, growth of the PcO6-colonized plants with NPs resulted in systemic increases in the expression of genes associated with tolerance to water stress. Increased expression in the shoots of other genes related to metal stress was consistent with higher levels of Cu and Zn in PcO6-colonized shoots grown with the NPs. This work demonstrates that plants grown with CuO or ZnO NPs showed cross-protection from different challenges such as metal stress and drought.


Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 782
Author(s):  
Karina Juhnevica-Radenkova ◽  
Jorens Kviesis ◽  
Diego A. Moreno ◽  
Dalija Seglina ◽  
Fernando Vallejo ◽  
...  

Historically Triticum aestívum L. and Secale cereále L. are widely used in the production of bakery products. From the total volume of grain cultivated, roughly 85% is used for the manufacturing of flour, while the remaining part is discarded or utilized rather inefficiently. The limited value attached to bran is associated with their structural complexity, i.e., the presence of cellulose, hemicellulose, and lignin, which makes this material suitable mostly as a feed supplement, while in food production its use presents a challenge. To valorize these materials to food and pharmaceutical applications, additional pre-treatment is required. In the present study, an effective, sustainable, and eco-friendly approach to ferulic acid (FA) production was demonstrated through the biorefining process accomplished by non-starch polysaccharides degrading enzymes. Up to 11.3 and 8.6 g kg−1 of FA was released from rye and wheat bran upon 24 h enzymatic hydrolysis with multi-enzyme complex Viscozyme® L, respectively.


Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 249
Author(s):  
Emmanuel Frossard ◽  
Frank Liebisch ◽  
Valérie Kouamé Hgaza ◽  
Delwendé Innocent Kiba ◽  
Norbert Kirchgessner ◽  
...  

New management practices must be developed to improve yam productivity. By allowing non-destructive analyses of important plant traits, image-based phenotyping techniques could help developing such practices. Our objective was to determine the potential of image-based phenotyping methods to assess traits relevant for tuber yield formation in yam grown in the glasshouse and in the field. We took plant and leaf pictures with consumer cameras. We used the numbers of image pixels to derive the shoot biomass and the total leaf surface and calculated the ‘triangular greenness index’ (TGI) which is an indicator of the leaf chlorophyll content. Under glasshouse conditions, the number of pixels obtained from nadir view (view from the top) was positively correlated to shoot biomass, and total leaf surface, while the TGI was negatively correlated to the SPAD values and nitrogen (N) content of diagnostic leaves. Pictures taken from nadir view in the field showed an increase in soil surface cover and a decrease in TGI with time. TGI was negatively correlated to SPAD values measured on diagnostic leaves but was not correlated to leaf N content. In conclusion, these phenotyping techniques deliver relevant results but need to be further developed and validated for application in yam.


1996 ◽  
Vol 41 (6) ◽  
pp. 1507-1510 ◽  
Author(s):  
Thi Bach Tuyet Lam ◽  
Kenji Iiyama ◽  
Bruce A. Stone

Plant Disease ◽  
2004 ◽  
Vol 88 (7) ◽  
pp. 724-730 ◽  
Author(s):  
S. A. Pereyra ◽  
R. Dill-Macky ◽  
A. L. Sims

Survival and inoculum production of Gibberella zeae (Schwein.) Petch (anamorph Fusarium graminearum (Schwabe)), the causal agent of Fusarium head blight of wheat and barley, was related to the rate of wheat (Triticum aestivum L.) residue decomposition. Infested wheat residue, comprising intact nodes, internodes, and leaf sheaths, was placed in fiberglass mesh bags on the soil surface and at 7.5- to 10-cm and 15- to 20-cm depths in chisel-plowed plots and 15 to 20 cm deep in moldboard-plowed plots in October 1997. Residue was sampled monthly from April through November during 1998 and every 2 months through April to October 1999. Buried residue decomposed faster than residue placed on the soil surface. Less than 2% of the dry-matter residue remained in buried treatments after 24 months in the field, while 25% of the residue remained in the soil-surface treatment. Survival of G. zeae on node tissues was inversely related to the residue decomposition rate. Surface residue provided a substrate for G. zeae for a longer period of time than buried residue. Twenty-four months after the initiation of the trial, the level of colonization of nodes in buried residue was half the level of colonization of residue on the soil surface. Colonization of node tissues by G. zeae decreased over time, but increased for other Fusarium spp. Ascospores of G. zeae were still produced on residue pieces after 23 months, and these spores were capable of inducing disease. Data from this research may assist in developing effective management strategies for residues infested with G. zeae.


2021 ◽  
Vol 45 (1) ◽  
Author(s):  
Wedad A. Kasim ◽  
Mohamed E. H. Osman ◽  
Mohamed N. Omar ◽  
Samar Salama

Abstract Background The effectiveness of two PGPB; Azospirillum brasilense NO40 and Stenotrophomonas maltophilia B11 was investigated in enhancing the drought tolerance of wheat (Triticum aestivum L.) seedlings cultivar Gemiza9. The inoculated or uninoculated grains were sown in unsterilized sandy soil and watered normally untill the 8th day. Drought stress was initiated by completely withholding water for 7 days (until wilting). Samples were collected after 15 days from sowing to evaluate some growth criteria, damage and defense indicators and to analyze the roots’ protein pattern. Results The results showed that inoculating wheat seedlings with these strains significantly diminished the inhibitory effects of drought stress on the relative water content of roots, shoots and leaves; area of leaves; contents of pigments (chlorophyll a and b) and ascorbic acid; and on the protein patterns of roots. Moreover, the bacterial inoculation notably reduced the drought-induced damage indicated by lower leakage of electrolytes and less accumulation of Malondialdehyde and hydrogen peroxide, surprisingly with less enhanced production of proline and activities of catalase and peroxidase than their uninoculated counterparts. Under normal conditions, inoculating wheat plants with these PGPB resulted in significantly promoted growth and elevated contents of pigments and altered protein patterns of roots. Conclusion Overall, we can say that both Azospirillum brasilense NO40 and Stenotrophomonas maltophilia B11 were able to deactivate the growth inhibition in wheat seedlings to some extent, while maintaining a certain level of efficient protection against damage under drought stress.


Sign in / Sign up

Export Citation Format

Share Document