SIST-TS CEN/TS 17724:2023

SLOVENSKI STANDARD
SIST-TS CEN/TS 17724:2023
01-februar-2023
Rastlinski biostimulanti - Terminologija
Plant Biostimulants - Terminology
Pflanzen-Biostimulanzien - Terminologie
Biostimulants des végétaux - Terminologie
Ta slovenski standard je istoveten z: CEN/TS 17724:2022
ICS:
01.040.65 Kmetijstvo (Slovarji) Agriculture (Vocabularies)
65.080 Gnojila Fertilizers
SIST-TS CEN/TS 17724:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS CEN/TS 17724:2023


CEN/TS 17724
TECHNICAL SPECIFICATION

SPÉCIFICATION TECHNIQUE

March 2022
TECHNISCHE SPEZIFIKATION
ICS 65.080
English Version

Plant biostimulants - Terminology
Biostimulants des végétaux - Terminologie Biostimulanzien für die pflanzliche Anwendung -
Terminologie
This Technical Specification (CEN/TS) was approved by CEN on 3 January 2022 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17724:2022 E
worldwide for CEN national Members.

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Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
3.1 Claims . 5
3.2 Terms relating to components . 11
3.3 Terms relating to application method . 17
3.4 Terms relating to sample preparation . 19
3.5 Terms relating to physical form . 19
3.6 Others terms relating to plant biostimulants . 20
Bibliography . 23

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European foreword
This document (CEN/TS 17724:2022) has been prepared by Technical Committee CEN/TC 455 “Plant
Biostimulants”, the secretariat of which is held by AFNOR.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a Standardization Request given to CEN by the European
Commission and the European Free Trade Association.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
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Introduction
This document was prepared by the experts of CEN/TC 455 “Plant Biostimulants”. The European
Committee for Standardization (CEN) was requested by the European Commission (EC) to draft
European standards or European standardization deliverables to support the implementation of
Regulation (EU) 2019/1009 of the European Parliament and of the Council of 5 June 2019 laying down
rules on the making available on the market of EU fertilising products (“FPR” or “Fertilising Products
Regulation”). This standardization request, presented as M/564, also contributes to the Communication
on “Innovating for Sustainable Growth: A Bio economy for Europe”. Working Group 5 “Labelling and
denominations” was created to develop a work program as part of this standardization request.
Technical Committee CEN/TC 455 “Plant Biostimulants” was established to carry out the work program
that will prepare a series of standards. The interest in biostimulants has increased significantly in
Europe as a valuable tool to use in agriculture. Standardization was identified as having an important
role in order to promote the use of biostimulants. The work of CEN/TC 455 seeks to improve the
reliability of the supply chain, thereby improving the confidence of farmers, industry, and consumers in
biostimulants, and will promote and support commercialization of the European biostimulant industry.
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1 Scope
This document specifies the terms and definitions referred to all the plant biostimulant field and it is
constituted by 6 subclauses:
3.1 Claims
3.2 Terms relating to components
3.3 Terms relating to application method
3.4 Terms relating to sample preparation
3.5 Terms relating to physical form
3.6 Others terms relating to plant biostimulants
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Claims
3.1.1 General principles
3.1.1.1
applicant R&D activities
data derived from R&D activities performed by the applicant
Note 1 to entry: R&D can be related to the plant biostimulant product development, testing and validation,
irrespective of the environment in which the type of data has been generated (e.g. under controlled conditions,
protected crop or field conditions).
Note 2 to entry: If the applicant has performed the R&D activities by its own technical resources or if the
applicant has subcontracted the R&D activities, as long as the owner of the outcome data from the R&D activities
is and can be proven to be the applicant.
3.1.1.2
bioavailability
degree to which substances can be absorbed/adsorbed by a plant or microbe, which is made available
at a site of physiological activity and so is able to have a biological effect
3.1.1.3
claim
effect(s) of the product that could be asserted on the product label of a plant biostimulant and after the
conformity assessment procedure
3.1.1.4
crop
cultivated plant including all components of the plant (above ground parts and below ground parts),
mushrooms, microalgae and macroalgae
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3.1.1.5
general principle
define the crops and quality criteria applicable to all plant biostimulants for carrying out the tests
necessary to justify the claim
3.1.1.6
plant
live plant and live parts of plants, including fresh fruit, vegetables and seeds
Note 1 to entry: It also includes microalgae, macroalgae and mushrooms.
3.1.1.7
plant biostimulant product
product stimulating plant nutrition processes independently of the product’s nutrient content with the
sole aim of improving the nutrient use efficiency, the tolerance to abiotic stress, the quality traits of the
plant or the plant rhizosphere or the availability of confined nutrient in soil or rhizosphere
3.1.1.8
protected crop
crop cultivation in greenhouses or plastic tunnels with or without specific control of climate conditions
according to the farming practice
EXAMPLE Cucumbers/tomatoes cultivation.
3.1.1.9
plant nutrient
chemical element used by the plant for growth and development, usually classified as primary
macronutrients, secondary macronutrients and micronutrients in the quantities required by the plant
Note 1 to entry: Carbon, hydrogen, and oxygen are also essential elements for plant growth.
Note 2 to entry: Primary macronutrients – nitrogen, phosphorus, potassium;
secondary macronutrients – calcium, magnesium, sodium, sulphur;
micronutrients – boron, cobalt, copper, iron, manganese, molybdenum, zinc.
3.1.1.10
trial series
combination of more than one trial result, all trials performed under the same trial protocol but in
different places and/or at different times
EXAMPLE Rate, crop, number of applications.
3.1.2
Nutrient Use Efficiency
NUE
measure of a plant’s ability to acquire and utilize nutrients from the environment for a desired outcome
based on (a) nutrient availability (b) uptake efficiency and/or (c) utilization efficiency
Note 1 to entry: Nutrient use efficiency is a complex trait: it depends on the ability to take up the nutrients from
the soil, medium, fertilizing products, but also on transport, storage, mobilization, usage by the plant.
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3.1.2.1
chelated plant nutrient
complexed plant nutrient
composition based on an inorganic form of the plant nutrient and a chelating or complexing agent,
resulting in a product that enhances the nutrient availability to plants
EXAMPLE A composition of chelated or complexed plant nutrient is a salt or oxide.
3.1.2.2
labelling
improve nutrient(s) use efficiency (the nutrient in question must be precisely specified) according to
the type of the product biostimulant’s activities and the type of plant nutrients
3.1.2.3
nutrient assimilation
uptake of nutrients into cells and tissues and consequent building up into more complex substances
EXAMPLE Converting available nitrogen into biomass.
3.1.2.4
nutrient availability
measure of the capacity of a nutrient to be acquired by the plant, depending on its presence in the soil
solution or on soil colloids
3.1.2.5
nutrient uptake
acquisition of nutrients by the plant
3.1.2.6
plant development
complex process by which the size, composition and organization of a plant changes during its life,
encompassing seed germination, vegetative growth, formation of flowers, bloom, fruit set and
maturation (embryo development)
3.1.2.7
plant metabolism
various biochemical reactions occurring in a living plant cell in order to maintain life and growth
3.1.2.8
plant nutrition
supply and absorption of chemical compounds needed for plant growth and metabolism
3.1.2.9
plant nutrition process
mechanism by which nutrients are utilized or converted to cellular constituents and used for energetic
or metabolic purposes
3.1.2.10
quality
desired attributes of cultivated organisms in terms of human or animal nutrition, marketing, aesthetics,
composition, agronomical trait, or technical
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3.1.2.11
substance
chemical element and its compounds in the natural state or obtained by any manufacturing process,
including any additives necessary to preserve its stability and any impurity deriving from the process
used, but excluding any solvent which can be separated without affecting the stability of the substance
or changing its composition
3.1.2.12
uptake efficiency
measure of the plant capacity to acquire nutrients from the environment
3.1.2.13
utilization efficiency
measure of the plant capacity to transform and valorize absorbed nutrients into more complex
substances
EXAMPLE Organic compounds, plant biomass.
3.1.3
tolerance to abiotic stress
ability to endure abiotic stress
3.1.3.1
abiotic stress
negative impact of non-living factors on the plant in a specific crop environment
Note 1 to entry: Crop tolerance to abiotic stress is addressed to one or more (multiple or combined) of the
following stress categories:
1) chemical stress;
2) light stress;
3) mechanical stress;
4) osmotic stress;
5) oxidative stress;
6) thermal stress;
7) water stress.
3.1.3.1.1
chemical stress
negative impact of chemicals (supra-optimal or sub-optimal chemical compounds or presence) on the
plant in a specific crop environment
EXAMPLE Salt stress, high solutes concentrations, mineral toxicity induced by heavy metals or excessive
application of mineral nutrients, adverse pH conditions, ozone stress, phytotoxic effects of xenobiotics.
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3.1.3.1.2
light stress
negative impact of light intensity and/or spectrum on the plant in a specific crop environment
EXAMPLE High irradiance or low irradiance, UV radiation.
3.1.3.1.3
mechanical stress
negative impact of a mechanical force on the plant or the root zone in a specific crop environment
EXAMPLE Wind, hail, agricultural operations.
3.1.3.1.4
osmotic stress
physiologic dysfunction caused by a sudden change in the solute concentration around a cell, which
causes a rapid change in the movement of water across its cell membrane
3.1.3.1.5
oxidative stress
disturbance in the normal redox state of cells that can cause toxic effects through the production of
peroxidase and free radicals that damage all components of the cells, including proteins, lipids and DNA
3.1.3.1.6
thermal stress
negative impact of temperature (supra-optimal and sub-optimal temperature) on the plant in a specific
crop environment
EXAMPLE Heat stress or cold stress such as chilling and freezing stress environment.
3.1.3.1.7
water stress
negative impact of water or high solutes concentration (supra-optimal and sub-optimal temperature
with the water level) or excessive transpiration on the plant in a specific crop environment
EXAMPLE Drought, high vapour pressure deficit, flooding.
3.1.3.2
priming effect
biochemical signalling induced by a first stress exposure that leads to enhanced defence system to a
later stress
Note 1 to entry: Priming effect results in a faster and stronger induction of basal defence mechanisms to abiotic
stresses. Biostimulants can act as a priming stimulus. Some priming effects have been shown to pass down plant
generations allowing a local population to improve fitness to the immediate environment.
3.1.3.3
xenobiotic
chemical substance found within an organism that is not naturally produced or expected to be present
within the organism
EXAMPLE Heavy metals, pesticides, ozone.
3.1.4
quality trait
desired attribute(s) of a crop regarding agronomical and marketable traits
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3.1.4.1
agronomical trait
property related to plant phenotype such as state, relative development, or amount of a plant organ (or
part), a plant cycle stage or a plant component that has proven contribution in one or more key
performance characteristics in plant production such as yield, plant value, end use or quality parameter
EXAMPLE Photosynthetic activity, flower number, root length, root density, foliar biomass, germination rate,
flower fertility, root growth, root development, seedling emergence, dry matter content, tillering, vigour, plant
biomass, uniformity of flowering, anticipation of flowering, uniformity in fruit set, fruit number, pod size, pod
length, spikelet size, spike length, reduction of internode length, increase of seed protein content and increase in
antioxidants and other functional compounds.
3.1.4.2
marketable trait
property which can improve the marketable value and/or marketable part of the crop such as
nutritional, organoleptic, technico-functional properties, fruit size, tuber size, tuber weight, physical
characteristic of the harvest
EXAMPLE Colour, firmness, size, sugar content, oil content, skin quality and increase of sensory attributes.
3.1.4.3
nutritional property
content of substances normally consumed as a constituent of food or feed, which provides energy, is
needed for growth, development and maintenance of healthy life or is a deficit of which will cause
characteristic bio-chemical or physiological changes to occur
EXAMPLE Protein, fat, carbohydrates, vitamins, minerals.
3.1.4.4
organoleptic property
property related to an attribute perceptible by the senses
EXAMPLE Appearance, basic taste, acidity, odour, flavour, colour.
3.1.4.5
techno-functional property
physico-chemical attribute which impacts a transformation process or any downstream use
EXAMPLE Food, feed, energy, cosmetology, pharmacology, building materials
3.1.5 Availability of confined nutrients in the soil or rhizosphere
3.1.5.1
available nutrient
element either present in the soil solution or exchangeable on soil colloids
3.1.5.2
confined nutrient
element present in the solid and gaseous phases of the soil including atmospheric nitrogen, excepting
soil colloids
3.1.5.3
improvement of availability of confined nutrients in the soil or rhizosphere
moving soil nutrient from the pool of confined nutrients to the pool of available nutrients
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3.1.5.4
nitrogen fixation
biochemical process by which molecular nitrogen (N2) is converted into ammonia or into other
nitrogen compounds, which are available to the living organisms including plants and microorganisms,
in soils, phyllosphere or in aquatic system
3.1.5.5
nutrient uptake
quantity of nutrient taken up from the external environment into a plant
3.1.5.6
phosphate solubilization
ability of some organic substances, beneficial microorganisms and other substances which help
beneficial microorganism to solubilize inorganic phosphorus from insoluble compounds in order to
improve the uptake of phosphorous
3.1.5.7
rhizosphere
volume of soil around living roots that is influenced by root activities
3.1.5.8
soil
layer of unconsolidated material consisting of weathered material particles, dead and living organic
matter, air space, and soil solution
3.1.5.9
soil colloid
finer size fractions of the soil (clay and organic matter), being also considered as the most chemically
active portion of the soil because of their large surface area and the chemical structure of the materials
involved
3.1.5.10
soil solution
liquid phase of the soil and its solutes
3.2 Terms relating to components
3.2.1
macroalgae
informal term for a large, diverse group of polyphyletic photosynthetic organisms that are not
necessarily closely related to each other
Note 1 to entry: Most are aquatic and autotrophic.
Note 2 to entry: Not including microalgae.
3.2.2
microorganism
any microbiological entity, including lower fungi, bacteria and viruses, cellular or non-cellular, capable
of replication or of transferring genetic material, including dead or empty-cell, micro-organisms and
non-harmful elements of the media on which they were produced
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3.2.2.1
Azospirillum sp.
gram-negative bacteria that belong to the alphaproteobacterial phylum
Note 1 to entry: Azospirillum is a Gram-negative, microaerophilic, non-fermentative and nitrogen-fixing bacterial
genus. Azospirillum are Gram-negative, do not form spores, and have a slightly-twisted oblong-rod shape.
Azospirillum have at least one flagellum and sometimes multiple flagella. The genus has about 20 species, the
relationships between all the species have not been resolved in details, however most likely they constitute a
coherent group.
Note 2 to entry: Azospirillum bacteria are aerobic non-fermentative chemoorganotrophs, vibroid, produce several
hormones, mainly auxins (not described for all species yet), and most of them are diazotrophic (fix atmospheric
nitrogen gas into a more usable form).
3.2.2.2
Azotobacter sp.
genus of Gram-negative, free-living, non-symbiotic, aerobic soil bacteria
Note 1 to entry: This is a genus of bacteria usually motile, oval or spherical bacteria that form thick-walled cysts
and may produce large quantities of capsular slime. They are aerobic, free-living soil microbes that play an
important role in the nitrogen cycle in nature, binding atmospheric nitrogen, which is inaccessible to plants, and
releasing nitrogen forms available to plants. The phylogeny of the genus is not resolved in details, so this
standards restrict in this context Azotobacter spp. to the species Azotobacter chroococcum, Azotobacter vinelandii
and Azotobacter beijerinckii which most likely comprise a coherent group within Pseudomonas.
3.2.2.3
bacteria
single celled prokaryotic microorganism, spherical or spiral or rod-shaped, that typically live in soil,
water, organic matter, or in the plants and/or in the bodies of animals
Note 1 to entry: Mostly reproduce by fission but can reproduce also via other methods.
Note 2 to entry: These single-celled organisms show a simple internal structure that lacks a nucleus and contains
DNA that either floats freely in a twisted, thread-like mass called the nucleoid, or in a separate, circular pieces
called plasmids.
Note 3 to entry: Bacterial cells are generally surrounded by two protective coverings: an outer wall and an inner
cell membrane. Some bacteria, like mycoplasmas, do not have a cell wall at all. Others have a third more protective
layer called the capsule. Whip-like extensions often cover the surfaces of bacteria, long ones are called flagella
(singular: flagellum) and short ones called pili (singular: pilum). Their role lays on helping bacteria to move and
interact with their environment (e.g. their host).
EXAMPLE Examples of reproductions are conidia, budding, cysts and endospores.
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3.2.2.4
fungus and yeast
diverse group of eukaryotic organisms harbouring chitin cell walls belonging to the fungal kingdom
Note 1 to entry: They are heterotrophic organisms encompassing an enormous diversity of taxa with varied
ecologies.
Note 2 to entry: Their genetic organization can be monokaryotic, dikaryotic or multinucleate often depending on
their lifecycle.
Note 3 to entry: They mostly reproduce through fission, budding or spore formation, either asexually or sexually.
In particular, yeasts are defined as eukaryotic, single-celled microorganisms classified as members of the fungus
kingdom. Yeasts are very common in the environment and are often isolated from sugar-rich materials.
EXAMPLE Life cycle strategies (symbiotic, saprotrophic, pathogenic, etc.) and morphologies ranging from
unicellular (single-celled such as yeast) to filamentous (such as moulds and many others) to large macroscopic
fruiting bodies (mainly Ascomycota and Basidiomycota).
3.2.2.5
microalgae
diverse group of microscopic polyphyletic photosynthetic organisms that are not necessarily closely
related to each other
Note 1 to entry: Most are aquatic and autotrophic.
Note 2 to entry: Can be single-cell or groups of cells joined together.
Note 3 to entry: Microalgae are distinguished from macroalgae in that microalgae are microscopic.
3.2.2.6
mycorrhiza
symbiotic relationship between a filamentous fungus and a plant
Note 1 to entry: In a mycorrhizal association, the fungus colonizes the plants’ root tissues either intracellularly
(as with endomycorrhiza) or extracellularly (as with ectomycorrhiza). This beneficial interaction brings several
advantages to the plants such as, for instance, enhancement of nutrients and water uptake.
3.2.2.6.1
endomycorrhiza
symbiotic association characterized by a filamentous fungal partner that colonizes the plants’ root
tissues intracellularly
EXAMPLE Four main groups of endomycorrhizal associations exist like arbuscular, ericoid, orchidoid and
sebacinoid mycorrhiza.
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3.2.2.6.2
ectomycorrhiza
hyphal sheath, or mantle, covering the root tip and an extracellular Hartig net of hyphae surrounding
the plant cells within the root cortex
Note 1 to entry: Beneficial symbiotic associations established by filamentous fungi belonging mainly to the
Ascomycota and Basidiomycota phylum with around 5 % to 10 % of coniferous and deciduous trees.
Note 2 to entry: In some cases, the hyphae may also penetrate the plant cells, in which case the mycorrhiza is
called an ectendomycorrhiza. Outside the root, ectomycorrhizal extraradical mycelium forms an extensive
network within the soil which increase plant nutrient availability and absorption. Since these fungi have septate
hyphae, hyphal fragments along with spores are considered long-term effective propagation structures.
3.2.2.7
rhizobium
beneficial bacteria belonging to the group named rhizobia, where the most relevant genera are
Rhizobium, Mesorhizobium, Ensifer and Bradyrhizobium
Note 1 to entry: Rhizobium belonging to this group are Rhizobium sp., Mesorhizobium sp., Ensifer sp.,
Bradyrhizobium sp.
Note 2 to entry: Legumes (Leguminosae or Fabaceae) are considered the second most cultivated crop, covering
14 % of the total cultivated land worldwide and providing an important source of food for human beings via direct
consumption or indirect consumption via animal feed. Leguminosae can ensure high quality protein-rich food and
feed due to a special symbiosis they have with specific microorganisms present in the soil that can fix in the
rhizosphere, atmospheric nitrogen. Those microorganisms can account for a 65 % of the total fixed nitrogen.
Those microorganisms have originally been called rhizobium. The word ‘rhizobium’ is actually derived from two
Greek words ‘rhizo’ meaning root and ‘bium’ meaning home. Since the late nineteenth century, all legume root-
nodule bacteria were placed in the genus Rhizobium. Gradually it was realized that they were rather diverse. A few
slow-growing rhizobia were split off into a new genus Bradyrhizobium. In the 1984 edition of Bergey’s Manual of
Systematic Bacteriology, all rhizobia were placed in the family Rhizobiaceae which included Bradyrhizobium and
Rhizobium. Since then, the number of bacterial genera representing rhizobia has increased rapidly; Rhizobia are
plant root nodule inhabiting, associative symbiotic, nitrogen fixing bacteria. Today the classification of the
different Rhizobia species is based the sequence of the 16S rDNA sequence comparison and physiological and
biochemical properties. Considering that taxonomy and phylogeny of bacteria is in continuous evolution and
considering that any current classification scheme is subject to future revision and considering moreover that
most of the rhizobial species in the alpha-proteobacteria class of phylum proteobacteria in Rhizobiaceae family
are in the Rhizobium, Mesorhizobium, Ensifer, or Bradyrhizobium genera, for the purpose of this document we will
consider the above-mentioned genera as referring to the Rhizobium sp. group.
Note 3 to entry: Other nodule-forming bacteria belong to the genus Frankia and interact with non-leguminous
species, including woody species of the families Betulaceae and Casuarinaceae. Such bacteria should be included
in the general wording of “Rhizobium” according to the terms of this document.
3.2.2.8
virus
agent considered on the borderline of a living organism, coming in several shapes which are widely
dist
...