ng as the result of the accumulation of SO,, which proved toxic to the tassels,
t they were now conceiltrating on finding a solution in which SO, would not
UGARCANE BREEDING TECHNIQUES PRACTISED AT CANAL POINT,
FLORIDA,
CARL 0 . GRASSLand B. A. BELCHER
Division of Sugar Plant Investigations, United States Defiartrnent of Agriculture
The sugarcane breeding work of the united States Department of Agriculture a t
444
CANE BREEDING SECTION
Canal Point is located in Palm Beach County on the eastern side of Lake Okeechobee.
I t is 48 miles west of West Palm Beach and 92 miles northwest of Miami. I t can be
reached by bus from either of these cities.
e
the
The sugarcane breeding station at Canal Point fronts on ~ i k Okeechobee,
second largest fresh water lake in the United States. The station buildings are on a sand
ridge which formerly extended along the beach of Lake Okeechobee. A large marl dyke
now separates that ridge from the present shore line.
About 17 acres of land are available at the station (see Fig. I). Most of this is a rich
Okeelanta peaty muck which grades into a low-mineral organic peat at the back of the
5
6
7
13
B
10
Greenhouse
~ o o lroom
Garage
Hot-water tank
Photo-period building
Mill shelter
Fig. I U.S. Sugarcane Breeding Station Canal Point, Florida. General Field Arrangement.
1
I
I
I
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I
1
1
I
I
station. A small area of Lake shore sand is also available in front of the station buildings.
All of the muck and peat land is very level and easy to cultivate. The Lake shore sandy
area is very low and is only a little above the normal water table.
For convenience of use, the station land is systematically laid out in uniform
rectangular areas about $ of an acre in size. These blocks are designated by letters of the
alphabet from front to bacli and by numbers from left to right. Thus, the first group of
rectangular bloclis in bacB of the station buildings is the A group and consists of AI, A2
and A3. At the C location the station widens and there are 6 bloclis in this group as well as
in the D and E groups. Two rectangular areas in front of the station buildings are linown
as FI and F2.
Each of the 26 rectangular bloclis on the station is bounded by a dirt roadway.
They are subdivided by numbered tiers and rows. This permits every plot of cane on the
station to be located accurately by a short symbol such as CI-26-3. In other words, this
symbol means that the sugarcane (28 NG 13, Imp. 632) at this location is in block CI,
tier 26, row 3 (see Fig. 2 ) .
c. o. GRASSL, 15A.
BELCHER
BLOCK: C-I
1952 PLANT CANE
ORIGINAL SUGARCANE VARIETY COLLECTION ON OICEELANTA PEATY MUCK AT
U S.SUGAR PLANT FIELD STATION, CANAL POINT, FLORIDA. PART I1
Spacing: 14 feet; Plots: 6 feet, Alleys: 4 feet;
R a t e of planting: z liiles, D a t e of planting: 3-4-52.
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3
I
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
130 -916117 -909116 -907104 -91999 -91794 -91593 -91492 -91391 -91290 -911-
28
NC 80 -90627
NC 78 -90526
NC 76 -90425
NC 74 -90324
NC 64 -90123 Shamsara -4822
NC 53 -89521
NC 51 -894zo
NC 50 -90259
NC 49 -goo18
NC 42 -89817
NC 40 -89716
NG 39 -896I5
NC 33 -893I4
NC 32 -89213
NC 31 -891Iz
NC 30 -89011
NC 29 -88910
NC 25 -8889
NC 24 -8878
f l ~
21 -8867
NC 20 -8856
NC 19 -8845
NC 18 -8834
NC I 7 -8823
NC 15 -8812
NC 11 -8801
NC 5 -879I
21NG49 -34221NG44 -34121NG37 -34021NG36 -33921NG3.5 -33821NG34 -337ZING33 -33621NG32 -335Z I N G ~ -334I
21NG30 -333-
Z I N G ~ -344I
21NG54 -34721NG55 -34821NG57 -350ZING@ -35128NG X-70728NG I -62628NG 2 -62728NG 3 -52028NG 4 -628-
28NGzog -65728NGzo8 -49828NG207 -50128NG206 -49928NGzo4 -63628NG203 -63528NGzoz -586z ~ N G10
I -51028NG1og -50728NG1o7 -427-
21NG23 -32921NG22 -328Z I N G ~ -327I
21NGzo -326ZINGIT -32321NG16 -322zrNG15 -321zrNG14 -320Z I N G I ~-319~ I N G I Z-318ZINGII -317ZINGIO -316ZING 9 -315ZING 7 -314ZING 6 -313ZING 5 -312ZING 4 -311ZING 3 -310PING 2 -309ZING I -308I ~ N G z -623~I
I ~ N G I -625~o
I ~ N G -624I ~ ~
96NGzqA -22696NG24 -22796NGzz -249g6NG16 -24796NG15 -22896NG14 -246-
z8NG 6 -630Z ~ N G I -863I
28NG1z -52328NG13 -63228NG14 -52428NG15 -52528NG16 -47928NG17 -52628NG18 -48328NGzo -47528NG21-52728NG22 -63328NG23 -52828NG24 -63428NG25 -52928NGz6 -53028NG27 -63528NG30 -63628NG31-63728NG32 -46328NG33 -53528NG34 -536z8NG35 -48228NG36 -47628NG37 -63828NG39 -39828NG40 -48128NG42 -48428NG43 -337-
28NG gg -65128NG 98 -50428NG 97 -50328NG 96 -50528NG 93 -65028NG go -51828NG 89 -51628NG 87 -51528NG 84 -64928NG 83 -64828NG 80 -40228NG79Y-67328NG 78 -64628NG 72 -51428NG 68 -51728NG 65 -512
28NG 63 -64528NG 62 -64428NG 59 -48728NG 56 -48628NG 55 -64328NG 54 -64228NG 52 -37928NG 51 -54028NG 72 -51428NG 47 -33828NG 46 -48628NG 45 -48528NG 44 -478-
3
4
2
Fig.
2.
28NGz1o -65828NGz11 -50228NG212 -54128NG213 -65928NG214 -66028NG215 -54228NG216 -66128NG217 -66228NGzzo -49528NG221-70628NG223 -86428NG224 -98028NG253 -86528NG256 -68528NG257 -68628NGz5g -54528NG260 -49428NGz61-50028NG262 -49328NG263 -49228NGz64 -66728NG265 -54628NGz66 -54728NG267 -54828NG268 -66828NG269 -97728NG273 -67128NG274 -67228NG7.79 -67328NG280 -67428NG282 -67528NG264 -55128NG285 -55223NG287 -67628NG283 -55428NG288 -95437NG6 -1035Tjemeng-Payaman
I ~ N G I -625~O
5
446
CANE BREEDING SECTION
At the time that a blocls. of land is planted, a map is made which shows the location
of every cane in the bloclc. (See Fig. 2). The name of the clone and the U.S. importation
number (if it is an imported cane) are recorded in the space corresponding to the plot.
The same name and number are embossed on a piece of metal tape and this is attached
to a stalce which is placed at the head of the plot. Each bloclc in cane is represented by a
map and these are arranged in a loose lkaf folder.in the order in which the bloclcs occur
on the station.
A similar folder contains a list of all the sugarcanes at Canal Point. The clone names
are listed alphabetically and each name has beside it one or more map symbols indicating
where the cane in question is being grown. This list is revised every year in order to keep
track of new plantings and importations.
This system of mapping and locating sugarcanes at Canal Point has been found to be
very simple and efficient. Keeping traclc of the more than I500 different clones maintained
there is an exacting job. Since many of the important breeding canes are planted in
several locations and plant and stubble crops of others may be present, the total number
of plots is frequentIy well over 2000.
The plots in general are very short. For breeding purposes, plots consisting of 6 to
12 feet of row or double row of cane in any given location have been found in most cases
to be sufficient. In the past, much longer plots were in use at Canal Point. Since 1948,
however, the policy has been to use short plots. I t was found that short plots that are
readily accessible from all sides are much more useful than the same area of land in long
plots. The reasons for that are numerous. Some sugarcanes appeaq to flower more
abundantly at the ends of the plots and these would be more useful in short plots. Other
canes do not flower well in plant cane and for these it is desirable to have numerous plots
so that first and later stubbles are always available. In the case of sparse flowering types,
it is desirable to have plots in as many different locations and environments as possible
in order to chance on the right combination of conditions that bring about flowering.
Different environments and different dates of planting may result in slight differences in
the time of flowering, an important factor in making certain combinations.
The station at Canal Point is fortunate in that 3 soil types-muclc, peat, and moist
sand-are represented. A fourth type-dry sand-is available for a limited number
of plots of breeding canes a t some distance from the station. A small plot of a given
clone on each soil type has been found to be much more useful than a single large
plot.
I t has been observed, for example, that certain late flowering clones will flower about
two or three weeks earlier on dry sand than on rich muck. A similar but less pronounced
difference in flowering date occurs between canes on wet sand and muclc. Some canes also
flower more profusely on sand or raw peat than on muclc.
I t is obvious that the preparation and care of several small plots involves much more
planning and field worlc than a single large one. This is no great disadvantage, however,
as the worlc in question comes largely at a time of the year other than the actual breeding
season. Anything that can be planned or accomplished before the breeding season begins
is well worth while if it makes that short period more productive.
Not only are the breeding plots at Canal Point small, but they are planted and
arranged so that all of them are readily accessible. This means that the alleys between the
different plots are wide and that the rows in which the plots occur are far apart. I t is not
necessary to step over or chop out numerous canes in order to get to flowering stalks in
C. 0. GRASSL, B. A. BELCHER
447
center of a plot. I t is possible to walk completely around most breeding plots without
tting or stepping on any stalks.
The alleys between tiers of plots are about as wide or slightly less than the plots are
g. With plots about 6, 8, 10, or 12 feet long, the alleys are generally 6, 7, or 8 feet wide.
alleys may be slightly narrower if the cane in the plots is tied upright to supports.
The spacing between rows of breeding cznes is 8 or more feet if the canes are tied
upright to supports. Breeding canes which are not tied to supports are generally spaced
in rows 14 to 16 feet apart. This wide spacing between rows makes it possible to walk
between neighbouring rows almost as fast as along the roadways between the blocks of
cane and thus facilitates the study and use of the canes in the various plots.
The access to many of the plots of breeding canes is further facilitated by planting
them in the outer rows and tiers of blocks, the centers of which are planted with seedlings
or other canes. Blocks which consist mainly of non-flowering young sugarcane seedlings
or noble canes are sometimes completely outlined by a layer of plots of breeding canes
along the roadways which surround all blocks.
Plots of breeding canes which are located along the roadways can be approached
directly by motor vehicles and this facilitates the production of location crosses. I t also
promotes the isolation of the breeding canes, since a given location can be planted to
all male-sterile clones or male-fertile clones as may be desired. The windward side of such
blocks is generally planted to male-sterile clones.
Attention has already been called to the practice of tying some breeding canes to
supports. Male-sterile clones which are to be used in location crosses are not tied in any
manner. I t is only the male-fertile clones and such male-sterile clones as are to be used in
solution crosses that are tied so that they may grow in an upright manner.
Breeding canes which are to be used in solution crosses are tied upright so that
straight flowering stallts may be available. This is accomplished by firmly setting stout
bamboo poles or iron pipes in the ground at both ends of,a plot and fastening a heavy
wire in the form of continuous narrow loops around the stools of cane. This is done in
August before the cane is tall enough to fall or be blown over.
At first the wire is left fairly loose and about 3 to 4 feet above the ground as the
strong winds of September, often of hurricane force, may break off the tops of the stalks
if they are tied to tightly. Later the wire is raised to about 5 to 6 feet and tightened so
that the stalks cannot sway very much.
That operation is very essential a t Canal Point as most of the breeding clones grow
vigorously there and become too tall to support themselves and consequently lodge late
in the season. This results in the stallts becoming very crooked just below the peduncle of
the inflorescence. Such stalks are not very easily used in the formation of solution crosses
as about 4 feet oremore of mature stalk should be available to bring about seed formation. Straight stalks, on the other hand, are easily handled and arranged in groups
when making solution crosses and can be cut to any length desired.
Another operation that is carried out before the breeding season is well under way
is the air layering of stalks of breeding canes for use in the production of greenhouse
crosses. Stalks of cane which are showing signs of short-leafing, an indication that an
inflorescence has been initiated, are selected. They are air layered by attaching a section
of modified stove pipe around the stalk and filling it with soil which is kept moist to
induce root formation. After a few weeks the roots are well enough formed so that the
stalks can be cut below the improvised stove pipe pots and brought into a greenhouse.
References p. 451.
CANE -BREEDING SECTION
That method is being supplemented by a procedure following that 'developed by
BRETT~
at Mount Edgecombe. A cane which appears to have a miniature inflorescence is
cut and brought into the greenhouse where the cut end is inserted through a hole in the
bottom of a pail which is filled with soil to induce root formation from the nodes. The cut
end of the stalk which protrudes below the pail is kept in a dilute solution of sulphurous
and phosphoric acid and a short piece of stall: is cut off twice a week when the solution
A modification of this procedure which was first tried in 1952, involved stimulating
roots to start growing from a few internodes before the stalk is cut. This is done by air
layering the internodes which will finally end up in the soil of the pail. A moist material
is kept around the root primordia until they begin to grow. In about a week or two, the
roots of most clones are sufficiently started so that the stallis can be cut and brought into
the greenhouse.
Some breeding canes are grown in tubs so that whole stools of cane can be brought
into the greenhouse after floral initials have been formed. With shallow tubs, it is
necessary to limit the number of stallis to 5 or 6 or they will be too weak to tassel.
Since the greenhouse facilities are very limited, generally only male-fertile clones
are air layered and later potted for use in the production of greenhouse crosses. Another
reason for this is that during most seasons an abundance of male-sterile material is
available outside. The greenhouse work is consequently based on potted stalks of malefertile clones which are crossed with whatever male-sterile cane that is selected from the
many breeding canes that may be flowering at the same time outside, The male-sterile
stalks are maintained by the Hawaiian acid-solution technique.
In order to facilitate the greenhouse work, 8 breeding chambers are available in one
of the two small greenhouse units a t Canal Point. These breed?ng chambers are designed
to reduce the amount of contamination from pollen of other male-fertile plants in the
greenhouse which may be flowering at the same time.
The chambers are air tight on the top and 3 sides and made of a transparent material
so that the light is not reduced very much. They are in groups of 4 which face outward
to the sides of the greenhouse. A narrow alleyway along the open sides permits tall stallis
of flowering cane to be carried to the different chambers.
Within the chambers, which are 5 feet wide and 4 feet deep, there are projecting slats
in the form of a horseshoe at 6+ and similarly at 76 feet above the ground level. This
frameworli of I by 2 inch boards is about 12 inches from the 3 enclosed sides of the chamber. I t is along this frameworli that the stalks of the parent canes are arranged and tied
during the pollillation period.
The tops of the chambers are 13 feet above the ground level and the sides project
downwards to about 6& feet from the ground. This permits one to walk beneath the
chambers and carry on the work of maintaining the stalks of cane during the pollination
period. Also, the lower portion of crooked canes can be interlaced in all directions without
restraining walls to interfere with their position. t
After the pollination period, which may take about a week to ten days, the female
parents are removed from the greenhouse and maintained outside until the seed is
mature. This permits the limited greenhouse space to be used again as soon as malefertile canes are available. When not in use by potted male-fertile canes, the chambers
can be used for the production of solution crosses between parents brought in from outReferences
p 451.
C. 0. GRASSL, B. A. BELCHER
[
449
As BRETT~
has pointed out, the advantages of greenhouse work are numerous when
rnatic conditions are unfavourable for pollen production. Canal Point is such a place.
uated at 27" N. Latitude, the average minimum night temperature during the flowereriod-primarily December and early January-is only about 59" F. which is not
suitable for pollen production.
Greenhouse work at Canal Point makes it possible to use as male-fertile parents,
many clones which ilormally are male-sterile there. This is a tremendous advantage as
itions a t Canal Point only a small percent of the breeding canes are
r words, temperature is an important factor in the sexual expression
nal Point and control of this factor in many clones permits control of
-
enhouse breeding work is being expanded at Canal Point, the main
eing accomplished by solution crosses. These were formerly made
ana windbreaksz but are now being &ade in the shelter of a tall photoperiod
h has been modified for this purpose. (See Fig. 3).
Fig. 3. View showing solution crosses with sugarcane varieties in the pollenization chambers located
in one section of the station photoperiod house.
,
I
Just as in the greenhouse, chambers have been constructed in the photoperiod
house so that crosses can be made in this building.
- The chambers are more numerousthere being 12 large and 2 narrow ones-as well as being taller and larger. Stalks up to
15 feet tall can be used and as manv as 20 stalks can be accommodated in a chamber
without undue crowding.
A large window 6 by 27 feet a t a height of 7 feet above the ground, furnishes some
light from the east while tall doors and a bank of electric lights furnish additional light.
n.o- ill effects
Since the stalks are kevt in this buildingu on111 during
-- ,.
- -- - - " the rnollination Ineriod
from the dim lighting are doticeable.
I t is interesting to note that the minimum night temperatures in that building are
from 4 to 10°F. warmer than outside. These higher temperatures and the absence of
wind have made it possible to obtain good results from combinations which would have
been failures if set up outside. December and January are very windy months at Canal
Point. This is an important limiting factor in the production of sugarcane seed.
.
I
References
fi. 451.
29
~
1
-
Control of the wind factor .in the production of solution crosses has been partially
accomplished by maintaining the flowering stalks for the pollination period in the
chambered breeding building. Control of the wind during the seed maturation period is
only partial a t present as the permanent windbreak of trees was planted in 1951 and the
banana windbreak now in use is not completely satisfactory.
Better control of the night temperatures in the breeding building is being considered
and experiments to evaluate its importance have been initiated in the greenhouse. A
test in this direction was made in December of 1952. Some stalks of C.P. 29-116-which
is male-sterile most years at Canal Point and male-fertile in a warm greenhouse-were
cut and placed in a warm greenhouse a t a stage of development when the inflorescence
was emerged only a few inches, the object being to determine if the inflorescence would
continue to emerge and flower in solution and if a 70°F. temperature during the short
period in question would result in the production of viable pollen.
An examination of the tassels in that experiment indicated that some viable pollen
was formed. This is encouraging as it may mean that outside temperatures up to the
stage of tassel emergence may not be significant in the determination of pollen production. Additional experiments are under way to test other clones from this point of view.
If these prove satisfactory, it will mean that the solution crosses made in the breeding
building need not be dependent on outside conditions for the initiation of pollen production if the night temperature is controlled. Since the male-fertile canes need only be
maintained until pollination is completed, the extra few days to a,week in solution during
the final stages of tassel formation would not involve much additional work.
Some sugarcanes do not set seed well in solution 'crosses and in such cases location
crosses are depended on. Location crosses must be relied upon when the stalks of the
female parent are lodged and very crooked and consequently very difficult to maintain
in a solution cross. At Canal Point the arrangement of the breeding plots is such that
location crosses may be more efficient than solution crosses from a labor standpoint if
damage from wind i n d cold is discounted.
The arrangement of the breeding plots has already been described, but it is desirable to point out that the isolation of the male-sterile canes is not complete. During a
warm period such as the early part of the 1948-49 season a t Canal Point, contamination
of location crosses by wind-blown pollen may be significant. It is estimated that the
contamination in many crosses at that time was as high as 5 %.
The manner in which location crosses are made is well known to sugarcane technologists and consequently will not be described in detail. I t should be pointed out, however, that the conditions a t Canal Point are not conducive to abundant seed set and
consequently many tassels are required in a cross if sufficient seed is to be produced.
This means th,at breeding frames with wide cross pieces are used in order to accommodate as many tassels as may be present a t a given location. I t also means that many
male-fertile inflorescences must be available so that the male-sterile tassels may be
compactly surrounded by them. The male-fertile stalks are maintained during the
pollination period in a dilute acid solution which codtains about 150 p.p.m. of H,SO,
and 85 p.p.m. of H,PO,. This solution is protected from the sun and replenished daily.
The tassels of the female parents are not collected until the uppermost flowers begin
to blow away. This occurs in about 25 days. They are then cut off a t the base of the
peduncle and placed in large paper bags-suit covers as used by dry-cleaning establishments are very satisfactory-and hung in a hot dry greenhouse compartment for a few
C. 0. GRASSL, B. A. BELCHER
45 I
are grown on sand to bring on early flowering, while early flowering clones are
REFERENCES
f
E, W. and SARTORIS,
G. B. 1936. Sugarcane: its origin and improvement. U . S . Dept.
r. Ysarbook, 561-623.
RETT, P. G. C. 1950. Flowering and pollen fertility in relation to sugarcane breeding in Natal. 7th
voc. I.S.S.C.T., 43-56
NDES,