High Molecular Size Humic Substances Enhance Phenylpropanoid Metabolism in Maize (Zea mays L.)

Schiavon, Michela; Pizzeghello, Diego; Muscolo, Adele; Vaccaro, Silvia; Francioso, Ornella; Nardi, Serenella

doi:10.1007/s10886-010-9790-6

Cited by 168 publications

(111 citation statements)

References 34 publications

(43 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Humic substances are end products of microbial decomposition and chemical degradation of dead biota in soils (Asli and Neumann 2010, Schiavon et al 2010) and are considered to be the most abundant naturally occurring organic molecules on earth (Simpson et al 2002) and the major components of soil organic matter (Nardi et al 2002). Interestingly, dissolved humic substances are common in freshwater bodies where they have been shown to interact with freshwater organisms, a topic reviewed by (Steinberg et al 2008).…”

Section: Humic Acidsmentioning

confidence: 99%

Agricultural uses of plant biostimulants

2014

View full text Add to dashboard Cite

Background Plant biostimulants are diverse substances and microorganisms used to enhance plant growth. The global market for biostimulants is projected to increase 12 % per year and reach over $2,200 million by 2018. Despite the growing use of biostimulants in agriculture, many in the scientific community consider biostimulants to be lacking peer-reviewed scientific evaluation. Scope This article describes the emerging definitions of biostimulants and reviews the literature on five categories of biostimulants: i. microbial inoculants, ii. humic acids, iii. fulvic acids, iv. protein hydrolysates and amino acids, and v. seaweed extracts.Conclusions The large number of publications cited for each category of biostimulants demonstrates that there is growing scientific evidence supporting the use of biostimulants as agricultural inputs on diverse plant species. The cited literature also reveals some commonalities in plant responses to different biostimulants, such as increased root growth, enhanced nutrient uptake, and stress tolerance.

show abstract

Section: Humic Acidsmentioning

confidence: 99%

Agricultural uses of plant biostimulants

2014

View full text Add to dashboard Cite

show abstract

“…Schiavon et al [50] showed for the first time a relevant effect of HS on secondary plant metabolism. Plants produce a remarkably diverse array of over 100,000 low-molecular-mass natural products, also known as secondary metabolites that are distinct from the components of primary metabolism since they are generally nonessential for the basic metabolic processes.…”

Section: Changes On Primary and Secondary Metabolismmentioning

confidence: 99%

“…According to Dixon [51], most of the secondary metabolites are derived from the isoprenoid, phenylpropanoid, alkaloid or fatty/ polyketide pathways and are produced to improve plant defence against biotic and abiotic stress. Schiavon et al [50] showed that HS treatment enhanced the expression of the phenylalanine (tyrosine) ammonia-lyase (PAL/TAL; EC 4.3.1.5) that catalyzes the first committed step in the biosynthesis of phenolics, by converting phenylalanine to trans-cinnamic acid and tyrosine to p-coumaric acid. The expression of PAL/TAL was accompanied by leaf phenol accumulation.…”

Section: Changes On Primary and Secondary Metabolismmentioning

confidence: 99%

Physiological responses to humic substances as plant growth promoter

Canellas

Olivares

2014

Chem Biol Techn Agric

336

220

View full text Add to dashboard Cite

Humic substances (HS) have been widely recognized as a plant growth promoter mainly by changes on root architecture and growth dynamics, which result in increased root size, branching and/or greater density of root hair with larger surface area. Stimulation of the H + -ATPase activity in cell membrane suggests that modifications brought about by HS are not only restricted to root structure, but are also extended to the major biochemical pathways since the driving force for most nutrient uptake is the electrochemical gradient across the plasma membrane. Changes on root exudation profile, as well as primary and secondary metabolism were also observed, though strongly dependent on environment conditions, type of plant and its ontogeny. Proteomics and genomic approaches with diverse plant species subjected to HS treatment had often shown controversial patterns of protein and gene expression. This is a clear indication that HS effects of plants are complex and involve non-linear, cross-interrelated and dynamic processes that need be treated with an interdisciplinary view. Being the humic associations recalcitrant to microbiological attack, their use as vehicle to introduce beneficial selected microorganisms to crops has been proposed. This represents a perspective for a sort of new biofertilizer designed for a sustainable agriculture, whereby plants treated with HS become more susceptible to interact with bioinoculants, while HS may concomitantly modify the structure/activity of the microbial community in the rhizosphere compartment. An enhanced knowledge of the effects on plants physiology and biochemistry and interaction with rhizosphere and endophytic microbes should lead to achieve increased crop productivity through a better use of HS inputs in Agriculture.

show abstract

“…Although some researchers consider that HS exert multiple direct effects on plant growth in addition to "hormone-like activity", especially under abiotic stress [7,28,36], others regard the effects of humates (in the absence of plant hormones) on plant growth as being indirect: they can alter soil properties by increasing friability, buffering pH, increasing water retention, complexing trace metals and increasing their availability [37] along with that of macronutrients. For example, Fe-humate is an effective Fe source for citrus trees planted in alkaline soils, which increased tree growth and fruit production of orange and grapefruit [38].…”

Section: Literature Reviewmentioning

confidence: 99%

“…Helal et al [56] showed that simple, inexpensive methods such as elemental analysis and potentiometric titration provided good agreement with the more powerful and expensive NMR and IR. Studies that include in-depth humate/humic acid characterisation include Ertani et al [26], Mora et al [28] and Schiavon et al [36].…”

Section: Future Researchmentioning

confidence: 99%

Commercial Humates in Agriculture: Real Substance or Smoke and Mirrors?

Lyons

Genç

2016

Agronomy

View full text Add to dashboard Cite

Soil humic substances (HS) are known to be beneficial for soils and plants, and most published studies of HS and humates, usually conducted under controlled conditions, show benefits. However, the value of commercial humate application in the field is less certain. This review attempts to answer the question: How effective are commercial humates in the field? Commercial humates, especially K humate, are used widely in agriculture today as "soil conditioners". A wide range of benefits is claimed, including growth of beneficial soil microbes; deactivation of toxic metals; improvements in soil structure including water retention capacity, enhanced nutrient and micronutrient uptake and photosynthesis; resistance to abiotic stress, including salinity; and increased growth, yield and product quality. Despite this, there is a surprising lack of solid evidence for their on-farm effectiveness and findings are often inconsistent. The industry relies largely on anecdotal case studies to promote humates, which are often applied at unrealistically low levels. It is recommended that products should be well characterised, physically and chemically, and that careful field studies be conducted on foliar humate application and pelletised humates at realistic rates, targeted to the seedling rhizosphere, for a variety of crops in a range of soils, including low C sandy and saline soils.

show abstract

High Molecular Size Humic Substances Enhance Phenylpropanoid Metabolism in Maize (Zea mays L.)

Cited by 168 publications

References 34 publications

Agricultural uses of plant biostimulants

Agricultural uses of plant biostimulants

Physiological responses to humic substances as plant growth promoter

Commercial Humates in Agriculture: Real Substance or Smoke and Mirrors?

Contact Info

Product

Resources

About