Specific Work Instructions: Cereal Crop Inspection Procedures

SWI 142.1.2-2

Table of Contents

Date

This version of the Cereal Crop Inspection Procedures was issued April 15, 2005.

Contact

The contact for this Seed Program Specific Work Instruction (SWI) is the Chief, Import and Domestic Office, Seed Section.

Review

This Seed Program Specific Work Instructions (SWI) is subject to periodic review. Amendments will be issued to ensure the SWI continues to meet current needs.

Endorsement

This Seed Program Specific Work Instruction is hereby approved.


Director, Plant Production Division


Date

Distribution

The most up to date version of this document will be maintained on the CFIA Internet site. In addition, the signed original will be maintained by the National Manager, Seed Section.

0.0 Introduction

The purpose of pedigreed seed crop inspection is to provide a third party unbiased inspection and completion of a report for the Canadian Seed Growers' Association (CSGA) on the isolation, condition, and purity of the crop. It is the inspector's responsibility to describe the crop as observed at the time of inspection.

1.0 Scope

This Seed Program Specific Work Instruction (SWI) outlines the procedures that an official crop inspector will follow in inspecting wheat, barley, oats, triticale, and rye crops for pedigreed status. These crop inspection procedures provide CSGA with assurance that production has been measured against the requirements for varietal purity and crop standards as specified by the CSGA's Canadian Regulations and Procedures for Pedigreed Seed Crop Production (Circular 6).

2.0 References

The publications referred to in the development of this SWI are those identified in SPRA 111, QSP 142.1 Pedigreed Seed Crop Inspection Procedure, CSGA's Circular 6 Canadian Regulations and Procedures for Pedigreed Seed Crop Production, and Rogues and Roguing.

In addition the following were used:

  1. Fehr, Walter, R., Principles of Cultivar Development, Volume 2, Crop Species, London, 1987.
  2. Stoskopf, Neal, C., Cereal Grain Crops, Virginia, 1985.
  3. Hervey-Murray, C. G., The Identification of Cereal Varieties
  4. http://www.hort.purdue.edu/newcrop/proceedings1996/V3-156.html

3.0 Definitions

For the purposes of this SWI, the definitions given in SPRA 101 and the following apply:

Aleurone
Granular protein in the outermost layer of endosperm of many seeds or cereal grains. Colour variation is used to distinguish barley varieties.
Anthesis
The flowering stage when the anthers burst, pollen is shed and the stigma is ready to receive the dispersed pollen.
Anthocyanin
Pigment ranging from red to violet to blue.
Awns
Conspicuous prolongations of the glumes or lemmas.
Chaff
Fragments of straw including the glume and hull removed from cereal grains in threshing or processing.
Circular 6
Canadian Seed Growers' Association Canadian Regulations and Procedures for Pedigreed Seed Crop Production.
Fatuoid
A common mutant found in oat crops and may be called a false wild oat. It usually has heavier protruding black awns distinguishable at maturity.
Floret
The stamens, pistils and lodiculae enclosed by the lemma and palea.
Glabrous
Having no projections or pubescence.
Glume
Two bracts found at the base of a grass or cereal spikelet.
Hull
The outer covering of a seed made up of the lemma and palea which may be removed freely as in wheat, or adhere as in hulled barley.
Hulless
A seed which has no outer covering or has an outer covering which is easily removed.
Inflorescence
The head of cereal crops consisting of flowers grouped on a central axis, the rachis.
Lemma
The lower or dorsal bract of the spikelet enclosing the seed. In wheat, it is readily removed with threshing, but may adhere in hulled barley and oats.
Monoecious
Having male and female reproductive organs borne on a single plant.
Nodes
The point on a stem from which leaves, shoots, or flowers grow.
OECD
Organisation for Economic Cooperation and Development.
Off-types
Plants in a seed field which deviate in one or more characteristics from the official description of the variety.
Open-pollination
The process by which pollen is transferred from plant to plant either by wind or insects.
Palea
Along with the lemma, forms two bracts that enclose the reproductive organs to comprise a floret.
Panicle
The inflorescence of oats consisting of a main stem with branches and sub-branches arising from a central axis.
Pollination
The process by which pollen is transferred from the anther (male part of a flower) to the stigmatic surface of the pistil (female part of a flower).
Rachilla
The axis of the spikelet that bears the florets.
Rachis
An extension of the stem on which the spikelets are found.
Speltoid
Common mutants in wheat crops. They can appear in a number of different forms, the most common and readily visible being the "tall late". This speltoid is taller and later than normal for the variety. The heads are longer and thinner with a distinct taper from base to tip. The glumes are strongly keeled with a square shoulder and generally are stiff and cannot be bent away from the spikelet without breaking. Speltoids tend to be self eliminating because they are late maturing, hard to thresh, small seeded and often have low fertility.
Supernumerary Spikelets
Certain wheat and triticale varieties produce a large proportion of ears with supernumerary spikelets. These extra spikelets arise from the nodes below and at right angles to the normal spikelets. These spikelets vary in size and development. In varieties which produce many supernumerary spikelets, the ears look ragged or untidy because the normal neat alternate arrangement of spikelets is confused by these extra spikelets arising at random up the length of the ear.
Variant
Any seed or plant which (a) is distinct within the variety but occurs naturally within the variety, (b) is stable and predictable with a degree of reliability compared to other varieties of the same kind, within known tolerances and, (c) was originally part of the variety as released. It is not an off-type.
Variety Description
A detailed listing of the characteristics used as the basis for identifying each cereal variety.
Variety Name
Name of the variety as established by the owner/breeder of the seed and as documented in the registration of the variety or on record with the CSGA for varieties of species not required to be registered.
Volunteer Plants
Unwanted plants growing from residual seeds from the previous crop or replanted crop.

4.0 Specific Inspection Procedures

4.1 Assessment of Application for Crop Inspection

The inspector must review the submitted application and/or preprinted forms. If any required information is missing, or if any additional information is required, the applicant should be contacted to ensure that all necessary information is present before commencing inspection of the crop.

As outlined in the Canadian Regulations and Procedures for Pedigreed Seed Crop Production, the land use and/or isolation requirements have been increased for some cereal varieties. There is at least one barley variety which has increased isolation distances. Therefore, it is critical that the description of variety is checked and the application be assessed for previous land use to identify the potential for volunteer plants.

4.2 Inspection Requirements

Each crop will require one inspection. Inspections must be performed between the time of heading through to maturity. Crops which are not inspected at the ideal growth stage for determining varietal purity may be declined.

The procedures for pedigreed seed crop inspection provided in QSP 142.1 must be used.

The inspector is responsible for reviewing the varietal description to become familiar with the characteristics of the variety and the allowable variants. For cereal varieties grown for grain and thus requiring registration, the variety descriptions are obtainable through the Product Registration System.

All wheat, barley, oats, triticale and rye can be grown for forage purposes. When growing cereal crops for forages, wheat and barley are the only two cereals for which variety registration is required, and thus it is only for these two that variety descriptions are available through PRS. For forage type oats, triticale, and rye which do not require variety registration when being grown for forage, variety descriptions are obtainable from the CSGA, or from the breeder or seed distributing company.

The inspector should refer to Appendix V for general descriptions of cereal species to assist in varietal identification.

4.3 Crop Inspection

Before starting the inspection, the inspector should ensure that s/he is at the right location. Information from the application including the maps should be verified with the field site.

The crop should be walked according to the predetermined travel pattern noting the isolation distance, condition and varietal purity of the crop, presence of noxious or difficult-to-separate weeds or other crops, and presence of disease. Areas of potential sources of contamination such as water runs, field grain bins, roadways, and manure pits should be examined closely. As a minimum, six counts per crop are required to be taken along the predetermined travel pattern so as to give the best representation of the crop.

4.4 Completion of the Report of Seed Crop Inspection

The preprinted Report of Seed Crop Inspection (CFIA/ACIA 1115) form is to be completed for crop inspection using the rough notes taken during the crop inspection. If a preprinted form is not available and a blank form is to be used, the inspector must state the reason for this in the Comments section.

The Report of Seed Crop Inspection must be completed fully, accurately and legibly to ensure the correct information is captured and recorded by CSGA. Failure to do so may cause economic hardship to the grower who could lose the pedigreed status of the crop. Inspectors must not anticipate any action of the CSGA with respect to the acceptance or refusal of the pedigreed status. The contents of a completed Report of Seed Crop Inspection must remain confidential under all circumstances. No areas of the form may be left blank. All efforts should be made to ensure correct spelling.

Key factors in completion of the report are:

As rye is an open-pollinated crop, particular attention must be paid during inspection to the neighbouring crop. On the Report of Seed Crop Inspection, the inspector must complete the section on open pollinated crops. This requires stating the variety of, the distance to, and the pedigree (if any) of other crops of the same kind adjacent to the crop. If a portion of the inspected crop is removed in lieu of an isolation, the inspector must state the distance that has been removed.

Only the abbreviations and codes recognized by CSGA which are listed in Appendix IV are permitted to be used on the Report of Seed Crop Inspection.

Other Crop Kinds, Difficult to Separate Weeds and Objectionable Weeds must be recorded as designated in Appendices I and II. Prohibited noxious weeds must also be recorded by frequency.

The area of Select plots should be reported as metres by metres. If it is suspected that the plots are larger than permitted by Circular 6, the inspector must obtain accurate measurements to support the observation. The inspector must notify the grower of the possibility of excessive acreage, and recommend that they contact CSGA to discuss options.

If true loose smut is observed in a barley crop, it is to be documented in the Report of Seed Crop Inspection in the Disease field of the Condition of Crop section.

If speltoids are observed, they are to be reported as variants.

When fatuoids, false wild oats or wild oats are noted in a crop of oats, they are to be included when performing counts. In the case of wild oats, they are reported in the Weeds Difficult to Separate section. In the case of fatuoids and false wild oats, they are reported in the Off-Types or Other Varieties section. When wild oats are present in cereals other than oats, they are to be reported in the Objectionable Weeds section by frequency.

In both western and eastern Canada, the presence of Tartarian Buckwheat is to be reported as an objectionable weed. When Tartarian Buckwheat is found in a buckwheat crop, it is to be included in the counts for Weeds Difficult to Separate.

Appendices

Appendix I: Crop Kinds to Report in Counts in the Inspected Crop

Reporting Other Crop Kinds Difficult to Separate

  CROP KIND OTHER CROP KINDS TO REPORT IN COUNTS
CEREALS Barley All cereals, buckwheat
Oats All cereals, fatuoids
Rye All cereals
Triticale All cereals
Wheat All cereals

Appendix II: Weeds to Report in the Cereal Crop

Inspected Crop Kind Difficult to Separate Weeds
(Report in Counts)
Objectionable Weeds
(Report by Frequency)
Oats Wild oats Cleavers (bedstraw)
Dock
Stickseed
Stinkweed
Tartarian buckwheat
Wild buckwheat
Wild mustard
Barley
Rye
Triticale
Wheat
None Cleavers (bedstraw)
Dock
Stickseed
Stinkweed
Tartarian buckwheat
Wild buckwheat
Wild mustard
Wild oats

Appendix III: Common Morphological Synonyms

Glabrous - Bald
Culm - Straw - Stem
Head - Spike - Ear - Inflorescence - Flower
Chaff - Glume
Awn - Beard
Glaucosity - Waxiness
Node - Joint
Pubescent - Hairy

Appendix IV: Abbreviations Recognized by CSGA

Abbreviation Impurity Abbreviation Impurity
2R Two rowed G2X Glume awns twice length of glume
2RRA Two rowed rough awned G3X Glume awns three times length of glume
2RSA Two rowed smooth awned GBL Glume beak is long
6R Six rowed GBS Glume beak is short
6RRA Six rowed rough awned HO Hulless oat
6RSA Six rowed smooth awned HRSW Hard red spring wheat
AL Awns long LM Later (less mature)
AR Awns rough NA No awns (awnless)
ARCH Awned and red chaffed NABGT No awns, brown glumes tall plants
ARCT Awned, red chaffed and tall NARC No awns and red chaffed
AS Awns short NARCT No awns, red chaffed tall plants
ASSM Awns semi-smooth NAT No awns, tall plants
AST Awns smooth, tall plants NAWC No awns and white chaffed
AT Awned and tall NAWGT No awns, white glumes and tall plants
AW Awns white RC Red chaffed
AWC Awned and white chaffed RS Red spring
AWCT Awned, white chaffed and tall SA Smooth Awns
BA Awns black TCO Tan chaffed oat
BARB Barbes TL Taller and later plants
BAT Awns black and tall plants TLGO Taller, light green oats
BCH Brown chaffed TPLA Taller and purple on leaf axis
ER Erect plants TPS Taller and purple on stem
FAT Fatuoids WCT White chaffed, taller plants
FWO False Wild Oats WO Wild oats
GIX Glume awns same length as glume    

Appendix V: Descriptions of Cereal Species

The following section outlines the characteristics displayed at time of inspection for cereal species commonly grown for pedigreed seed.

The following characteristics are to be considered for identification of purity of variety for which the specifics are captured in the variety description obtained from the Product Registration System. For varieties that do not require registration such as forage type oats, triticale, and rye, the inspector must refer to the Form 300 descriptions available from the CSGA.

Some characteristics that are useful in identifying varieties for more than one species are indicated in the following table. Other characteristics which are more species specific are outlined in the species specific section which follows.

Species Characteristic Characteristic Description
Wheat, Triticale Straw pith This observation is made by cutting the straw clearly at a mid-point between the ear and the upper stem node. The thickness of the wall depends on the amount of soft tissue beneath the hard epidermis and is classified as either hollow, thick-walled or solid. This characteristic must not be regarded as definitive as variations do occur as a result of different environmental and climatic conditions. In sawfly resistant varieties, the pith is always solid or very thick-walled as a defence mechanism.
Wheat, Barley, Triticale, Rye Head attitude (at maturity) Attitudes range from: erect (upright to 30°), semi-erect, inclined (30° to 90°), horizontal, semi-nodding, nodding (>90°).
Wheat, Barley, Triticale, Rye Head shape The shape is often determined by the density of the grains. Varieties with a very dense grain arrangement on a short head usually results in a triangular shaped head. Shapes include: tapering, parallel, oblong, clavate and fusiform.
Wheat, Rye, Triticale Head density Determined by the relative length of the rachis segments, and ranging from lax to dense. Varieties with visible spaces between grains when viewed from the side as a result of long rachis segments within the head are described as lax.
Oats, Barley Hulledness Hulled oats and barleys have strong glumes which hold the seed in the spikelets, whereas hulless oats and barley are essentially "naked" and the seeds are released easily from the lemma and palea.
Wheat, Barley, Triticale Glume pubescence Glumes of certain uncommon varieties are covered with a mat of fine hairs which resemble felt or fine fur. This is a very distinct character that is classified as glabrous, slightly pubescent, or strongly pubescent.
Wheat, Barley, Triticale Awn length The actual length of the awns as they extend beyond the head can vary greatly from extending longer than the length of the head itself to extending less than the length of the head.
Wheat, Barley, Triticale, Oat Waxiness (head and culm) Many varieties have plant surfaces possessing a coating of wax. The absence of wax gives a very different appearance after head emergence in that the flag leaves and spikes appear "yellow-green" instead of "blue-green". It can be confusing, because "non-waxy"; surfaces actually have a glossy or wax-finished appearance whereas "waxy"; surfaces have a thin deposit of dull waxy powder which is white, pale-grey or light blue in colour. The best places to find a potentially waxy surface are the base of the ventral sides of the lemma, the lower part of the palea, or the stem. It should be recognized, however, that the location of wax may be influenced by the environment.

Wheat (Triticum spp.)

Wheat is a monoecious plant with perfect flowers. It reproduces sexually as a self-pollinated crop. Cross pollination occurs at usually <3%, however possibly may be as high as 10% in some genotypes and/or environments. The inflorescence of wheat is a determinate composite spike (head). Spikelets are alternately arranged on the rachis. Each spikelet has two bract like empty glumes that enclose two to nine florets. The outer parts of each floret consist of a lemma and a palea.

Three types of wheat exist. Winter wheats are the same species as spring wheats and share the same identification characters. Winter wheat differs from spring wheat in that it has a winter habit, requiring vernalization, the exposure to cool temperatures and short day lengths in order to initiate reproduction.

Durum wheat is a distinct and separate species from common spring and winter wheats. The heads and neck of durum wheat are more compact than those of common wheat and appear squarish in cross section.

For identification purposes, wheat can be grouped into two groups. Those possessing awns > 5 cm in length up to the length of the head (bearded), and beardless whose awns are either absent or very short in comparison. Similarly awnless, apically awnletted and awnletted are used to describe awn characteristics.

In most of the awnless varieties, the length of the lemma awns increases towards the apex of the head, and in certain varieties, the length of the awns may justify the description of semi-bearded.

It is of particular importance when inspecting pedigreed seed, that one is aware of einkorn, emmer and spelt species. Although they are not certified in large quantities in Canada, they are of concern as contaminating sources. Einkorn along with emmer and spelt are often referred to as' the covered wheats', since the kernels do not thresh free of the lemma, palea, and glume upon harvesting. Today's modern wheats are as a result of selections caused by natural mutations starting with einkorn, emmer, and spelt.

The following characteristics are to be considered for verification of purity of variety.

Glume Characteristics: variations will be encountered within a variety and also over the length of the ear.

Glume internal imprint: these clearly marked areas are caused by the pressure of the external surface of the lemma. This area can be seen as dark shadowy areas between the veins or nerves which run from the base of the glume to the beak and shoulder margins and are classified as absent, small, medium, or large.

Other characterizing morphological traits to consider when identifying wheat varieties.

  • Height (stem plus spike, excluding awns)
  • Head length (excluding awns, use first tiller)
  • Head shape
  • Head waxiness
  • Head awnedness
  • Head attitude
  • Head density
  • Rachis margin pubescence
  • Pubescence on upper culm internode
  • Upper culm internode waxiness
  • Culm neck shape
  • Straw pith
  • Supernumerary spikelets
  • Awn attitude
  • Awn colour
  • Awn length
  • Glume beak shape and length
  • Glume shoulder shape and width
  • Glume length
  • Glume width
  • Glume pubescence

Diagrams

Straw Pith (in cross section at middle of internode below the neck)

This diagram shows the different Straw Pith (in cross section at middle of internode below the neck) - Hollow, Thick-walled, Solid

Spike Density

This diagram shows the Spike Density - Lax, Medium, Dense

Spike Awnedness

This diagram shows the Spike Awnedness - Awnless, Apically awnletted, Awnletted, Awned

Spike Shape

This diagram shows the Spike Shape - Tapering, Oblong, Clavate, Fusiform

Rachis Margin Pubescence

Diagram of the Rachis Margin Pubescence
Diagram of the Rachis Margin Pubescence

Culm: Shape of Neck

This diagram shows the Culm: Shape of Neck - Straight, Curved

Glume Beak Shape

This diagram shows the Glume Beak Shape - Obtuse, Acute, Acuminate

Glume Shoulder Shape

This diagram shows the Glume Shoulder Shape - Wanting, Oblique, Rounded, Square, Elevated, Apiculate

Glume Shoulder Width

This diagram shows the Glume Shoulder Width - Narrow, Medium, Wide

Glume Pubescence

This diagram shows the Glume Pubescence - Glabrous, Pubescent

Spike and Spikelet Characteristics of Einkorn, Emmer and Spelt

This diagram shows the Spike and Spikelet Characteristics of Einkorn, Emmer and Spelt

This diagram shows the the Spike and Spikelet Characteristics of Einkorn, Emmer and Spelt

Barley (Hordeum vulgare L.)

There are two main types of cultivated barley: two-row and six-row. Each type has three spikelets at each rachis node (one central and two laterals), and each spikelet contains one floret. Groups of spikelets are arranged in an alternate and opposite fashion on the rachis. The lateral spikelets of two-rowed barley are sterile and the central is fertile, resulting in two rows of kernels on the rachis. All florets of six-rowed barley may be fertile, resulting in six rows of kernels when viewed in cross section or from the top of the spikelet. Cultivated barley species are naturally self-pollinating.

In addition to the main two-row versus six-row distinguishing factor, barley varieties also vary in that they may be winter or spring, hulled or hulless, for forage or grain, and for malting or feed purposes. Some forage varieties have increased isolation requirements as specified by the breeder. This additional requirement can be found in the "Additional Comments" section of the variety description within the Product Registration System.

Unlike wheat, the characteristics identifying barley are considered as definitive in that they do not vary over a range, resulting in greater certainty when identifying varieties. The following characteristics are to be considered for identification of purity of variety.

Plant Characteristics After Heading: Many characteristics useful in identifying varieties are best considered when the seeds on the head are ripe. For this reason, some of the following information may not be entirely accurate as inspections are conducted before the grains begin to mature.

Kernel: In six-row varieties, the central kernels are slightly larger and plumper than the lateral kernels, while the kernels of two-row varieties are all uniform in shape and size. The length of hair on the rachilla can be useful in distinguishing varieties. It ranges from short, to long and feathery. The aleurone colour of a dehulled barley kernel may be yellow, white or a blue shade.

Lemma awns: In some varieties, especially those with dense heads, the awns tend to spread out like a fan. In certain varieties, the lemma awns are discarded as the grain ripens. This "dropping-off" of awns can also occur in normal varieties under certain climatic conditions such as extreme drought.

Anthocyanin: Many varieties contain this purple or red pigment in various parts of the plant in the vegetative and reproductive stages. Most pigmented varieties tend to lose this colour as the plants ripen, but some will retain the pigment in the five dorsal lateral nerves of the developing grain. Positive identification of non-pigmented varieties by reference to fully mature grain is impossible, but the anthocyanin pigment's presence can be detected in growing plant material. The best places to look are in the basal leaf sheath of the first leaf, the stem nodes and auricles, and especially in the tips of the awns if the plant is still green.

Other characterizing morphological traits to consider when identifying barley varieties.

This table represents other characterizing morphological traits to consider when identifying barley varieties. All three columns are the characterizing morphological traits of the barley varieties. For more information contact Seeds Section at 613-225-2342.

  • Lemma awn tip colour (anthocyanin)
  • Head length
  • Glume hair length
  • Awn length
  • Head attitude
  • Glume awn barbs
  • Height (stem plus spike)
  • Head waxiness
  • Glume length
  • Collar shape
  • Head shape
  • Glume pubescence
  • Aleurone colour
  • Rachilla hair length

Diagrams

Glume Length

This diagram shows the Glume Length - Short, Long, Medium

Length of Barley Awns' Extension (relative to ear length)

This diagram shows the Length of Barley Awns' Extension (relative to ear length) - Longer, Equal, Shorter

Awn Attitude

This diagram shows the Awn Attitude - Parallel, Broad, Triangular

Rachilla Hairs

This diagram shows the Rachilla Hairs - Long Haired, Short Haired

Collar Shape

This diagram shows the Collar Shape - V-shaped
v-shaped:

The collar has a raised margin on the rear part with the forward part protruding downwards.

This diagram shows the Collar Shape - platform
platform:

The entire upper surface of the collar is almost flat or convex. The margin or edge of the collar is flat or slightly sloping downwards.

This diagram shows the Collar Shape - cup
cup:

The margin is raised to create a cup-like structure. The base of the first rachis segment is concealed.

This diagram shows the Collar Shape - open
open:

The forward part of the collar is not complete like the other types, but forms a deep open slit for a considerable way down the stem.

Spike Attitude

This diagram shows the Spike Attitude - Erect, Semi-Erect, Horizontal, Semi-Nodding, Nodding

First Rachis Segment

This diagram shows the First Rachis Segment - Slightly Curved, Curved, Straight

Barley Kernel

Diagram of the Barley Kernel
Diagram of the Barley Kernel

Oats (Avena sativa L., A. nuda)

Oats is an annual, self pollinating grass for which out-crossing seldom exceeds 0.5%. The stem is composed of a series of nodes and internodes with alternate leaves. The stem usually contains four to seven elongated internodes and the uppermost internode is often as long as the combined length of all other internodes. Mature stems terminate in a loose, open panicle. The main axis of the panicle terminates in a single spikelet. Alternate groups of branches arise from the main axis and each branch terminates in a single spikelet. The number of spikelets per panicle normally ranges from 25 to 45 depending on genotype and growing conditions. Each spikelet usually contains from one to three florets enclosed in empty glumes with the tip of one glume extending slightly above the other. Usually only the two basal florets are fertile, but on occasion 3 or more are fertile. Each flower is perfect and has three stamens, a pistil and 2 lodicules. The flower is enclosed by two bracts, the lemma and palea, which are known as the hulls on the harvested oat grain. While both spring and winter types of oats exist, winter hardiness in oats is not sufficient to survive in Canada.

The following characteristics are to be considered for verification of purity of variety.

Panicle type (Head shape): Varieties can be divided into two groups according to their panicle type. Varieties whose panicles are equilateral or equal-sided give the general appearance of a triangle or cone. This arrangement is the most common. Varieties whose panicles are unilateral appear one-sided so that all the branches tend to be on one side of the main rachis of the panicle. These varieties are sometimes referred to as "side oats". Unilateral panicles tend to lean over due to the lop-sided weight of the grains and can be easily identified when acting as a contaminant in a crop of plants with equilateral panicles. Sometimes, however, this trait is not the result of a contaminant, but a border row effect whereby equilateral varieties resemble unilateral varieties along the outside of border rows due to excess water along the field's edge. Unilateral panicles may possess a thickened swelling or false node below the lowest whorl of branches. Semi-unilateral and sub-unilateral varieties exist in that some branches do not conform entirely to the unilateral characteristic. A few varieties change from the equilateral type to semi-unilateral as they ripen.

Length of hairs or spines on lower panicle node: Panicle branches arise from nodes on the flowering stem. The bases of these branches are generally swollen and covered with very small spines or hairs. Varieties can be distinguished by the number and relative length of these hairs on the swollen bases.

Rachilla Characteristics: (observe at green stage shortly after heading) The rachillas on the upper region of the panicles possess certain features which can be used in varietal identification.

Rachilla grooves: In many varieties the rachilla has two longitudinal depressions down each side of a central raised section. These depressions are often grooved and the extent in which they extend down the rachilla is a varietal characteristic.

Rachilla pubescence: In most varieties the rachilla is glabrous, though some varieties have short hairs, spines or barbs which are attached to the surface of the rachilla.

Lemma awn presence: In certain varieties most primary grains may have awns arising from the median nerve on the dorsal side of the lemma. The presence or absence of awns and the number of primary grains producing these awns can be greatly influenced by environmental factors thus caution should be used when using this feature as an identifying characteristic.

Other characterizing morphological traits to consider when identifying oat varieties.

  • Panicle branch position
  • Presence of secondary rachis node
  • Number of panicle branches
  • Panicle branch length
  • Angle between rachis and dominant side branch angle
  • Average number of florets per spikelet
  • Rachis shape
  • Height (including panicle)
  • Number of panicle whorls

Diagrams

Panicle Characteristics

Diagram of the Panicle Characteristics
Diagram of the Panicle Characteristics

Panicle Shape

This diagram shows the Panicle Shape - Equilateral, Unilateral

Panicle Branch Position

This diagram shows the Panicle Branch Position - Erect, Semi-Erect, Horizontal, Drooping, Strongly Drooping

Triticale (Triticosecale)

Triticale is a cross between wheat and rye. Morphologically it resembles its wheat parent, but exhibits the more vigorous growth characteristics of rye. Triticale has either a spring or winter growth habits, has variable plant height and tends to tiller less than wheat. The inflorescence of triticale is a spike resembling that of wheat more than rye, and is often considerably larger than that of wheat and rye. As with both parents, the spike of triticale is composed of a series of some 30 to 40 spikelets arranged alternately on each side of the rachis. Each spikelet consists of 4 to 8 florets, of which usually only 3 are fertile. Each spikelet is surrounded by two glumes of chaff, and the lemma and palea enclose each floret in the spikelet. The lemmas generally taper into a 7 to 10 cm long awn. The awn lengths vary between varieties. Due to it's free-threshing property, the lemma and palea do not adhere to the kernel during threshing. It is a self pollinating species with the pollen being released within the floret. The period of anthesis in triticale varies among varieties but generally is longer than in wheat and thus more susceptible to out-crossing. Anthesis normally begins in the central portion of the spike when the spike has completely emerged from the leaf sheath. Triticale varieties are often one or two weeks later maturing than wheat.

Characterizing morphological traits to consider when identifying triticale varieties.

  • Head shape
  • Awn colour
  • Culm neck shape
  • Head density
  • Awn length
  • Stem pubescence
  • Head attitude
  • Awn attitude
  • Straw pith
  • Head length
  • Supernumerary spikelets
  • Stem waxiness
  • Head colour
  • Glume shoulder shape
  • Rachis margin pubescence
  • Head waxiness
  • Glume beak shape
  •  Head awnedness
  • Glume pubescence

Rye (Secale cereale)

Morphologically, rye most closely resembles wheat of all the cereals. Although the leaves are similar in shape to those of wheat, they tend to exhibit a typical bluish colour. Rye is typically taller and tillers less profusely than wheat. Rye seedlings can be distinguished from other cereal seedlings by it's fine pubescence covering the sheath. The plants have numerous, highly branching, deep roots. The inflorescence is a rather lax, slender spike, 10 to 15 cm long. The spikelets at each node of the rachis usually contain three florets, with the two outer florets being fertile and the central one being sterile. As does wheat, the lemma and palea which enclose the floret are free-threshing. The lemmas which are longer than the glumes, taper gradually and often bear barbs on the keel and awns of intermediate length. The kernels are longer and more slender than those of wheat. Rye differs from other small grains in that the crop is largely cross-pollinated, as most rye plants are self-sterile, and characteristically some florets fail to set seed. The spike attitude varies with variety and can be erect or nodding. Rye varieties can be distinguished from one another by observing their spike form: fusiform, elliptic or oblong, the kernel size and shape, and the degree of blue or green colouration. Because of it's open glume orientation for cross-pollinating purposes, rye is highly susceptible to ergot. Due to the tendency for rye to ripen quickly which makes the plants more prone to shattering, there is a narrow window for time of inspection.

Characterizing morphological traits to consider when identifying rye varieties.

  • Plant height
  • Head length
  • Head waxiness
  • Stem pubescence
  • Head density
  • Head attitude
  • Degree of colouration
  • Head shape
  • Head awns

Diagram

Rye Plant

This diagram shows the Rye Plant