Jan. 1, 1925 
A Study of Variability in the Burt Oat 
59 
Plants of this variant type were 
grown at the Akron and Manhattan 
stations in 1921 and at the Akron 
Field Station and the West Virginia 
Agricultural Experiment Station in 
1922. These experiments have shown 
that this multiflorous condition is 
heritable, though there is considerable 
variation in the progenies with respect 
to the percentage of kernels remaining 
inclosed in the lemmas after threshing. 
A spikelet of this variation is shown in 
Plate 7, in comparison with those of 
normal Burt oat and Avena nuda, the 
hull-less oat. 
LOOSE PALEAS 
Several plants were observed among 
the 1920 progeny at both the Akron 
;and Manhattan stations in which the 
paleas of the kernels did not closely in¬ 
close the caryopsis. In some of these 
the palea was curled away from the 
lemma, leaving the caryopsis exposed. 
Such kernels were seeded in 1921 at both 
stations and the plants grown proved 
the condition to be heritable to some 
-extent. Plate 8 shows several of these 
kernels. 
FALSE WILD OAT 
Criddle (24) observed false wild forms 
in the Early Ripe oat, a variety very 
similar to Burt. These false wild forms 
have been discussed by Fischer (35), 
Norton (98), Criddle (24, 25), Nilsson- 
Ehle (93, 96), Newman (86, 87), Zade 
(153,154), Atwood (6) , Von Tschermak 
{137), Pridham (106), Robb (113), 
Agar ( 1), Gante (41), Hayes and 
Garber (47), Crepin (23), Akerman 
(2 ), Garber ( 42 ), and Garber and 
Quisenberry (43). A few plants bear¬ 
ing kernels resembling the false wild 
forms described in publications named 
above were first observed in the 
material grown at Akron in 1920. 
More recently a number of such aber¬ 
rant individuals were found in Burt at 
Akron, and one was selected from a 
strain of this variety by W. H. von 
Trebra at the Colby (Kansas) Substa¬ 
tion in 1924. In these forms the basal 
cavity was very prominent on the 
upper as well as the lower kernels of 
the spikelets. Both the primary and 
secondary kernels bore awns which 
were markedly twisted. Abundant 
hairs practically surrounded the base 
of the lemma and were present on the 
rachillas of both kernels. The presence 
of a few hairs also was observed on the 
dorsal surface of some kernels. The 
false wild kernels were of a yellowish- 
Ted color. Kernels of false wild oats 
which occurred in selection No. 16-3 of 
Kansas strain No. 6076 of Burt grown 
at Akron in 1920 are illustrated in 
Plate 9. 
SUMMARY 
A review of the literature on classi¬ 
fication and breeding experiments with 
oats is presented, with special refer¬ 
ence to the characters considered in 
this paper. 
Experiments of different investiga¬ 
tors have shown that certain strains of 
Burt oat are resistant to crown rust 
and to smut. These characters add to 
the value of the variety. 
The Burt oat has considerable eco¬ 
nomic value due to its wide adaptabil¬ 
ity, early maturity, drought resistance, 
and resistance to smut and crown rust. 
The commercial Burt oat is com¬ 
posed of a large number of distinct 
strains and many of these are heterozy¬ 
gous. This variety has been classified 
as Avena sativa by Carleton (17), 
Avena sterilis by Etheridge (33), and 
in other ways by other investigators. 
There seems to be little basis for the 
suggestion of Waller (141) that the 
Burt oat belongs to Avena barbata. 
Burt may belong to a distinct group, 
as suggested by Norton (98), but the 
writers consider it as belonging to Avena 
byzantina, the species accepted by 
many European taxonomists as in¬ 
cluding cultivated descendants of Avena 
sterilis. This species is recognized as 
being variable in its breeding behavior 
and as containing strains which resem¬ 
ble those of Avena sativa. 
Investigators do not agree concern¬ 
ing the amount of natural crossing 
which takes place in oats. The writers 
believe that field crosses may occur 
rather frequently, the amount of natural 
crossing varying with the variety and 
environmental conditions. 
Spikelet disarticulation in the Burt 
oat appears to breed as a simple 
monohybrid. The roughened type of 
base resulting from fracture, very 
similar to that of Avena sativa, appar¬ 
ently is dominant. The base result¬ 
ing from abscission and containing a 
prominent cavity apparently is re¬ 
cessive. 
Two types of floret disjunction are 
found in Burt oat, the sativa or dis¬ 
articulating form predominating. The 
byzantina or basffracture form, in its 
breeding behavior, somewhat suggests 
a cross involving multiple factors. 
The development of basal hairs in 
Burt is a character which appears to be 
complex in breeding behavior. Prob¬ 
ably several factors are concerned. 
The abundant long hairs appear to be 
recessive. 
Several factors probably determine 
the breeding behavior of awns in the 
Burt oat. The twisted awn bred more 
nearly true than did any of the others. 
