An "Intergeneric" Hybrid: Aglaomorpha X Drynaria

7 Pages·1991·3.8 MB·

by  Barbara Joe Hoshizaki

American Fern 37-43
Journal 81(2): (1991)
An
Aglaomorpha
x Drynaria
"Intergeneric" Hybrid;
Barbara Hoshizaki
Joe
Mildred Mathias Botanical Garden, University of California. Los Angeles, California 90024
In 1969 was asked to identify a garden plant obviously related to
I
known
Aglaomorpha, but not matching any species. was uncertain whether
I
was Aglaomorpha
the plant a variation of coronans (Wall, ex Mett.] Copel. or
a hybrid involving that species. In 1972, herbarium specimens were sent
to
C. V. Morton of the United States National Herbarium and to F. M. Jarrett of the
Royal Botanic Gardens, Kew. Mr. Morton wrote that the plant was near A.
wondered
coronans but hardly that species. Dr. might possibly be a
Jarrett
if it
hybrid between Agiaomorpha and Drynaria. Others thought might be a
it
variant of A. coronans. From the study of Drynarioideae by Roos (1985), was
I
was
able to ascertain that the plant not a variant of A. coronans, nor the hybrid
(A. xleporella], nor any other taxa treated in his monograph.
The was
original source of this unidentified plant Mr. Al Roberts, a
who
nurseryman and was
specialized in ferns the proprietor of the former
Robert's Subtropical Gardens, Los Angeles, California. Before the appearance of
me
had
this unidentified plant, Mr. Roberts related to that he routinely planted
different spores together convenience and had done so with species received
for
from
the Berkeley Botanical Gardens, University of California, Berkeley,
me unknown
was
California, This led to suspect the plant a hybrid.
Unmistakably present in this putative hybrid are characteristics of A. coronans,
a plant that was well known in cultivation long before 1954 and was often grown
by
Herbarium
fern collectors. records indicate that Dr>'naria rigidula (Sw.)
Bedd. was growing at the Berkeley Botanical Garden in 1953 and had been
had
distributed to tradesmen; herbarium records indicate Mr. Roberts this
species by 1958. He apparently sowed A. coronans together with D. rigidula and
produced hybrid sometime between 1953 and before 1959, the year his
this
nursery
closed.
my
During this period records indicate that other aglaomorphas and drynarias
were and examined them
in local cultivation, therefore as possible parents.
I
These species were found to be unlikely parents as the putative hybrid has no
and
hint of the strongly contracted fertile lobes relatively large, consistently
many
round sori of A, meyeniana Schott, nor the immense fronds and small
round two rows
scattered sori of A. heraclea (Kunze) Copel., nor the sori in of
D. querci/oJia Sm. A. coronans one parent, the hybrid's pinnatisect
(L.) If is
J,
blades and notched pinnae rule out these unlikely parents further, as they all
have pinnatifid blades and entire pinnae. This D. rigidula with pinnate
left its
fronds and margins the most plausible second parent. Also, of the
serrate as all
unlikely parents are tender plants, while the proposed parents and their
putative hybrid are hardier.
BOUmCPL
MISSOURI
JUL
26
199^
38 FERN
Mr
Mr. From was
Roberts. here oassed from
it
limited
Fern
quantities.
fanciers called A. 'Roberts' or A. species. In recent years Serge
it
Zimberoff
Santa Rosa
of Nursery, Santa
Rosa, California, propagated the plant
throu
known
A.
as 'Roberts' (Zimberoff
From
above
the
circumstantial evidence and
study
a of the morphological
features, the parents
of this putative hybrid are considered be A. coronans and
to
D. an
rigiduia, intergeneric hybrid under
currently accepted
generic boundaries.
The may
known
hybrid
be
as:
X
Aglaonaria
roberlsii Hoshizaki, nothogen. & nov.—
nothosp. Type: Orange,
California, from a plant grown by Leo
1973'
Porter, Porter's Tropicals, August
Hoshizaki 73-131
[LA).
Fig.
1 f-h, Fig. 2a,
c.
Planta hybrida
hortensis Aglaomorpham
inter coronantem
(Wall. ex. Mett.)
ummonom
sessilibus
vel
substipitatis, basibus
humus-retinentibus,
anguste
vel
late dila-
tatis, sinuosis vel vadose
vel profunde
lobatis, partibus pinna-
foliaceis
m
menta
unica
termmalia
parva
elongata
vel abortiva, hydathodis
sed
nullis apicibus
venarum
plemmque
tumidis,
soris
orbiculatis, oblongis
vel elongatis, ple-
nimque
maxima
m
the
ermediate
appearance
of the frond The
(Fig. foliaceous mainly
1). part
is
pmnatisect
in the hybrid,
pinnatifid
in A. coronans, and
pinnate
in D. rigiduia
^^e.fshtly constricted above
their adnate base
llT kTI^ in the hybrid
(Fig.
while -
2a). the width
of the lobes
is relatively even ^
in A. coronans
a- - "
bases
are tapered
in D. The
rigiduia.
hybrid's
adjacent pinnae
are
mar
""
A. coronans
T/ 1 1°
adjacent
lobes are connected by wing
'""T""" a
along t'
the
rach.s, whereas
in D. rigiduia pinnae
are The
separate.
green
lighter
™"^
""^''
TV""^ ^'^° -P^'^*« «>« hybrid from A.
wh
onans"
o ''f'l*'
^
^''" ™'"'
^^"i
DrZZnM, ' ^f " l'""hery texture, and
^
L •
?'^""'*
f
al "P^^
"" '^' ^y^'''^ Pi""^tely '"bed
to
n ''"T ''
the
™'"
"'"^
"."
«„r '" ^ <''™8''"= '^niinal segment may
S that
u^' 'I
f-
™--
^'^
\^"«rl?i;?_!^^^P'/" '°bes_at base
U):
its (Fig. in D.
conform
"^
wiZr* °*''™^''5' ''"'''
.' '^'^ '"°^' deeper
'"
Ae P'^^^' ("«'
than
"^ 7;"'^S'"™=
naargin), while
they
are
shaHol entire in A. coronans
and
7°i
* *'"
*'' cartilaginous
'^rP"' margin)
in D. rigiduia
h!h (Fig.
d
,h
" f
"«' but
'° the vein
Hvd f ! *rm"' •'>'''-:'d tips are often enlarged.
tifj/;*
are present
A. coronans
but
m "^^^^il in ligiuuia. ine son
i^. are
intprmpHtato u
intermediate .u^r.
Tr, shape bet* ween .,
the
parents
(Fig. or sometimes more
2), A.
like
AGLAOMORPHA DRYNAEJA
HOSHIZAKI: x
39
C
O
O
3:
g
Fig. Fronds of parents and hybrid, a. Aglaomorpha coronans, frond, b-e. Dry-naria rigiduJa. b,
1.
young frond frond
more exposed environment.
frond from
robertsii. frond, atypical frond, h.
f. g,
occasionally
there
Comparison and
two two coalesced of these
there are or partly sori (Fig. 2c).
and
1.
1
-
40 AMERICAN FERN JOURNAL: VOLUME NUMBER
81
2 (1991)
-S^
c <^S?W?K^*M^aS»MM«^>;" ^J-l'^'^iVi>n t ^ -_^
d
-/iV,
^
^
m
-.
^ "j .% T"L
w
-X
"* '^^w^.
-^'
^ i^^.
^^^"-
:* -L
<^ :^^^
-^
*
i;
.>
.>sa^;>
^..:... _->::> .
_\^ -:-.-_-.-:^j-j
:^^ t^
-V
«
/ iV "
L-'^
^
^
_ ^-
E
.^.^v
I^
Mb
*5» ^ ^^-^
*i«
;#:
rvj:.:'-^- - ^
4 y
#
c
r"- ! ^b^'
v;»i-;«vdfcv^r«a(K'
-^_ -^^^^.'lW> Wf.
.n . .--V v^;- .^,-i^F^v. ^-i£«4M&:
Fig. xAgJaonaria
a, pinnae
2. robertsii, bases Aglaomorpha
(0.3 xj, b, coronans.
fertile area x).
(2.5
xAgiaonana
c,
robertsii, fertile area (2.5x). Drynaria
d. rigidula, area (2.5x).
fertile
climatic
California. Fronds
that appear
proportionately more
humus-collecting
than
uniform
^^ ^r ^L L — —m— ^^ ^ * V A^ih ^k ^L -_*' ^^ '%. J M m m^J ^m^Jkl MAfta^ IHIJI IIIIK MM IIJ ^^ I I V I
range from
being
like humus-collecting
fronds
of D. rigiduJa
as in Fig. Ic (except
longer with
deeper and
lobes, a thinner
texture] being an
to like A. coronans
trond
(except and
stouter
less foliaceous). Both
parents,
particularly D.
rigidula
may
mfrequently
produce
atypical fronds
as well Leaves
(Fig. le). transitional
between
foliage leaves and
nest leaves have been
observed on
wild
plants
of
Drynaria
(Zamora and
Vargas,
Greenhouse
1973).
plants of A. coronans and
the
more
tronds with
broadly humus
dilated
base
s ^^ereas
i\,:
less favorable
conditions produce
i\ fronds with
greater
constriction
at the pinna and more
bases,
a
slender frond
structure
in
general
(Fig. Ih].
(/Nomenclature/
1980
(Article
19A) recommends
that
interspecific hybrids
introduced
into cultivation should
—
xi«iiit cvcii
u, u J ™* *>-t 11 iiu unit;! ccuuilLtiivvaarr
-,£ 4,u^ ^.,. •^
• • 1 , ,
t
"
™'"™^
^'' "'"''
^ °^'"'= f"' this in.ergeneric
Tu-
nysnd III" °
hybrid
given
is as follows:
xAgkonaria
robertsii Santa Rosa
cv.
Hoshizaki, nov
cv.
"°"7"P'"^- ^^' \
general growth
and
'" habit frond
ffoorrmm exrPnf ^f°"°"^
except
the
foliaceous
part of the blade
mostly
pinnatisect
of smaller
and
firm,
'" medium'gr'een. kncTot
ff°°':,'-«'h, Pinnae
.oTn™H:n?.Tl e
''^''"^ ^"stricted
above
f their adnate
margins
base,
Ihs^ri
•
;
segment
sometimes
the
from
morphological
and
anatomical
features of the may
parents
AGLAOMORPHA
HOSHIZAKI: x DRYNARIA
41
Table Morphological Aglaomorpha coronans, xAglaonaria and
1. Characteristics of roberfsii,
Drynaria
rigidula
Aglaomorpha xAglaonaria
coronans robertsii Drynaria rigidula
cm cm 1-2 cm
Rhizome 2-3 2-2.5
diameter:
1.
Rhizome vascular Oval, dorsal side with Elliptic to broadly lunate, the dorsal side shorter,
2.
bundle pattern: 2 deep invaginations often interrupted by leaf traces [protrusions)
more complex
or
Vascular bundle All about equal Dorsal bundles (ca. 4) slightly larger than others
3.
size:
Rhizome
scale Basifixed Basifixed Peltate
4.
attachment:
Rhizome
Auriculate Auriculate Peltate
scales
5.
base:
6. Rhizome scale 2 united 2 united 1 protuberance
protuberances protuberances
teeth:
Medium Medium
Rhizome Slender
scale stout stout
7.
teeth shape:
Rhizome scale Not noticeably dark Not noticeably dark Dark
8.
color
at
attachment point
Frond Monomorphic Monomorphic Dimorphic
types:
9.
10. Frond attachment: Sessile Sessile Foliage fronds stalked,
humus-coUecting
fronds
sessile
11. Frond base shape: All fronds narrowly All fronds narrowly Foliage frond petioles
naked
to broadly dilated, to broadly dilated. or ridged to
humus-collecting humus-collecting narrowly winged;
humus-collecting
fronds broad at base
Pinnate
12. Blade, foliaceous Pinnatifid Pinnatisect
part:
Connection Connected along Connected by separate, not
13. of
lobes or pinnae: costa by a wing extension of thin connected by
cartilagenous margin extensions
14. Lobe or pinna Uniformly wide or Mostly somewhat Tapered at the base to
base: wider towards the constricted above the a short, narrowly
winged
base base stalk
cm
Lobe pinna 15-35 x 1.2-5 cm 6-26 X 1.5-2.5 cm 8-25 X 0.5-3
15. or size:
16. Lobe or Entire Obscurely serrate Shallowlj'^ serrate
pinna margins:
An
17. Frond apex: elongate, entire Pinnately lobed to a Aborted, or if apical
pmna
appearmg
with 2-3 smaller small terminal
lobe
conform
base segment, or aborted present,
lobes
at its
Not
18. Veins: Prominently raised Moderately raised or slightly raised
mm
mm
19. Minor areole size: Mostly 2 or less Mostly 2 or less Mostly greater than
mm
2
42 AMERICAN FERN VOLUME
lOURNAL:
Table
Continued.
1.
Aglaomorpha
xAglaonaria
coronans
robertsii Drynaria
rigidula
Minor
20. areole shape Very shape
variable in Variable in shape and Mostly longer than
and
and
orientation:
orientation orientation wide with long
axis
oblique
to costa
21. Hydathodes:
Present Absent
Absent
Vein
22.
tips: Stongly enlarged Enlarged or not Not enlarged
23. Foliage
texture: Hard, leathery Firm
Firm
24. Foliar hypodermis:
Present adaxially Absent
adaxially Absent
adaxially
25. Foliage color: Dark green Medium Medium
green
green
Laminar
26.
scales: Absent
maturity
at Present, sparse
Present, sparse
27. Scales on
costa
Basifixed
Basifixed,
Peltate, pseudopeltate
and
rachis:
pseudopeltate,
or or basifixed
infrequently
peltate
Shape
28.
of sori: Oblong Round
to linear Round
to sublinear
29. Sori between
Several in a row, sometimes
1, 2, 1
main
lateral veins sometimes
coalesced
coalesced
or separate
of lobe or pinna:
30. Sporangia; Normal
Normal
malformed
or Normal
31. Spores:
Normal
Irregularly shaped Normal
32. Perispore: Smooth
or folded
Verrucate
Verrucate
hybrid. Only few
a more
of his
readily
definable
characters
are listed in Table
This hybrid
touches on
1. the generic
relationship between
Aglaomorpha
and
deemed
[ram
fig. 7.43).
Waenei
incom
rresular
°^''
7J
.T.V^f P^^™'
^"'^ ">«y indicate simple
dom2Tn^nr; T""''''
''^'""'^°^ hydathodes
and
r^ J the softer texture and
lighter color
nf •
*e
Phenotype
D^naria
ot the
parent'while
.l'^'"L™r^l^°"il'° the
rt
--
wuM^;:s;;;;^'=^-^
-!^i-
-^^-^
^^^?!rn
hether
common
patterns
are
fems
to certain
AGLAOMORPHA
DRYNARIA
HOSHIZAKI: x
43
Acknowledgments
thank very much M. G. Price for his valuable comments and suggestions on this paper and for
I
the Latin description. also am indebted to Prof. W. H. Wagner, Dr. Alan R. Smith, Dr. Gerald
I
J
Gastony, and Prof. Mildred E. Mathias for their assistance.
Literature Cited
A
new
Chandra, Subhash. concept of Drynaroid Fern Gazette 12:225-229.
1982. ferns.
Roos, M. C. 1985. Phylogenetic systematics of the Drynarioideae (PoJypodiaceaeJ. Thesis, Utrecht.
Verhandeligen van de Konenklijke Nederlandse Akademie van Wetenshappen, Aid.
Natuurkunde, Tweede Reeks, Deel 85. Pp. 1-302.
Wagner, W. H., 1969. The role and taxonomic treatment of hybrids. Bioscience 19:785-789.
Jr.
Zamora, p. M. and N, S. Vargas. 1973. Notable variations in leaf forms of Drynaria. The Philipp.
57:55-71.
Agric.
ZiMBEROFF, 1986. Lesson: Aglaomorpha meyeniana. LAIFS (Journal of the Los Angeles
S.
Fern 13:70-74.
International Society)