Cereal growth staging scales attempt to objectively measure the growth of
cereal
A cereal is any Poaceae, grass cultivated for the edible components of its grain (botanically, a type of fruit called a caryopsis), composed of the endosperm, Cereal germ, germ, and bran. Cereal Grain, grain crops are grown in greater quantit ...
s.
BBCH-scale (cereals)
In
agronomy
Agronomy is the science and technology of producing and using plants by agriculture for food, fuel, fiber, chemicals, recreation, or land conservation. Agronomy has come to include research of plant genetics, plant physiology, meteorology, and ...
, the BBCH-scale for cereals describes the
phenological
Phenology is the study of periodic events in biological life cycles and how these are influenced by seasonal and interannual variations in climate, as well as habitat factors (such as elevation).
Examples include the date of emergence of leaves ...
development of
cereal
A cereal is any Poaceae, grass cultivated for the edible components of its grain (botanically, a type of fruit called a caryopsis), composed of the endosperm, Cereal germ, germ, and bran. Cereal Grain, grain crops are grown in greater quantit ...
s using the
BBCH-scale The BBCH-scale is used to identify the phenological development stages of plants. BBCH-scales have been developed for a range of crop species where similar growth stages of each plant are given the same code.
Phenological development stages of plan ...
.
The phenological growth stages and BBCH-identification keys of cereals are:
*
1 A leaf is unfolded when its ligule is visible or the tip of the next leaf is visible
*
2 Tillering or stem elongation may occur earlier than stage 13; in this case continue
with stages 21
*
3 If stem elongation begins before the end of tillering continue with stage 30
Feekes scale
The Feekes scale is a system to identify the growth and development of
cereal crops introduced by the Dutch
agronomists Willem Feekes (1907-1979) in 1941.
This scale is more widely used in the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
than other similar and more descriptive
scales such as the
Zadoks scale Cereal growth staging scales attempt to objectively measure the growth of cereals.
BBCH-scale (cereals)
In agronomy, the BBCH-scale for cereals describes the phenological development of cereals using the BBCH-scale.
The phenological growth ...
or the
BBCH scale. Like other scales of crop development, the Feekes scale is useful in planning management strategies that incorporate plant growth information for the use of
pesticides
Pesticides are substances that are meant to control pests. This includes herbicide, insecticide, nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, microbicide, fungicide, and lampric ...
and
fertilizers to avoid damaging the crop and/or maximize
crop yield
In agriculture, the yield is a measurement of the amount of a crop grown, or product such as wool, meat or milk produced, per unit area of land. The seed ratio is another way of calculating yields.
Innovations, such as the use of fertilizer, the c ...
.
Zadoks scale
The Zadoks scale is a
cereal
A cereal is any Poaceae, grass cultivated for the edible components of its grain (botanically, a type of fruit called a caryopsis), composed of the endosperm, Cereal germ, germ, and bran. Cereal Grain, grain crops are grown in greater quantit ...
development scale proposed by the Dutch
phytopathologist
Plant pathology (also phytopathology) is the scientific study of diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomyc ...
Jan Zadoks
Jan Carel Zadoks (born 6 February 1929) is a Dutch botanist and a professor emeritus of ecological plant pathology at Wageningen University & Research.
Career
Zadoks studied biology at the University of Amsterdam and received his PhD. cum ...
that is widely used in cereal research and agriculture.
Knowing the stages of development of a crop is critical in many management decisions that growers make. They are represented on a scale from 10 to 92. For example, in some countries,
nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
and
herbicide
Herbicides (, ), also commonly known as weedkillers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page fo ...
applications must be completed during the
tiller
A tiller or till is a lever used to steer a vehicle. The mechanism is primarily used in watercraft, where it is attached to an outboard motor, rudder post or stock to provide leverage in the form of torque for the helmsman to turn the rudder. ...
ing stage. In
France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...
, the recommendation for the first nitrogen application on wheat is 6 weeks before Z30, with the second application on Z30.
Wheat
Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...
growth regulators are typically applied at Z30. Disease control is most critical in the stem extension and heading stage (Z31, Z32, Z35), in particular as soon as the flag leaf is out (Z37). The crop is also more sensitive to heat or frost at some stages than others (for example, during the meiosis stage the crop is very sensitive to low temperature). Knowing the growth stage of the crop when checking for problems is essential for deciding which control measures should be followed.
Examples of typical stages
* during tillering
**Z10: one leaf
**Z21: tillering begins
* during stem extension
** Z30: ear is one centimeter long in wheat
** Z31: first node visible
** Z32: second node visible
** Z37: flag leaf
* during heading
**Z55: the head is 1/2 emerged.
* during ripening
**Z92: grains are ripe
References
*
*
*{{cite journal
, last = Witzenberger
, first = A.
, author2=H. Hack , author3=T. van den Boom
, title = Erläuterungen zum BBCH-Dezimal-Code für die Entwicklungsstadien des Getreides - mit Abbildungen
, journal = Gesunde Pflanzen
, volume = 41
, pages = 384–388
, date = 1989
Further reading
* J.C. Zadoks, T.T. Chang, C.F. Konzak, "A Decimal Code for the Growth Stages of Cereals", ''Weed Research'' 1974 14:415-421.
External links
Citation Classic of 1985 Agronomy
BBCH-scale
Cereals