Hayes and Garber - Cucurbit Breeding

D. Lemma with four teeth or awn points
Ȧvena abyssinica.
CHAPTER VII
CLASSIFICATION AND INHERITANCE OF SMALL GRAINS
OTHER THAN WHEAT
In the cases of barley and oats quite usable classifications have
been proposed. The general adoption of such classification
schemes is desirable for often great confusion results from the
incorrect use of varietal names. Classification schemes can
not be given in detail in a plant breeding text. It seems sufficient
here to point out the genetic relationship between wild and
cultivated species and to give the major so-called species groups
for the various crops. The more important botanical and
agronomic characters which are commonly used in varietal
classification have also been mentioned. As crossing must
frequently be resorted to as a means of improving small grains,
the student should have a working knowledge of the known facts
of inheritance with respect to particular characters.
CLASSIFICATION AND INHERITANCE IN OATS
A workable classification of cultivated American oat varieties
and the basic wild species has been made by Etheridge
(1917). The following outline of species groups is taken from
his publication;
A. Kernel loose within the surrounding hull; lemma and glumes alike in
texture
Avena nuda.
AA. Kernel firmly clasped by the hull; lemma and glumes different in
texture.
B. Upper grains persistent to their rachillas Avena sterilis.
BB. Upper grains easily separating from their rachillas.
C. Lemma bearing as teeth or awn points.
DD. Lemma with two teeth or awn points.
E. Lemma elongate, lanceolate, with distinct awn
points
Avena strigosa.
EE, Lemma short, abrupt, blunt, rather toothed than
awn-pointed
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