Bermudagrass variety evaluations in Florida

Material Information

Bermudagrass variety evaluations in Florida
Series Title:
Agronomy research report
Alternate title:
Bermuda grass variety evaluations in Florida
Ruelke, Otto Charles, 1923-
University of Florida -- Agronomy Dept
Place of Publication:
[Gainesville Fla
Department of Agronomy, Agricultural Experment Station, IFAS, University of Florida
Publication Date:
Physical Description:
[6] p. : ; 28 cm


Subjects / Keywords:
Bermuda grass -- Florida ( lcsh )
City of Gainesville ( local )
In vitro fertilization ( jstor )
Grasses ( jstor )
Agronomy ( jstor )
non-fiction ( marcgt )


General Note:
Caption title.
General Note:
"September 1976."
Statement of Responsibility:
O.C. Ruelke.

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
62395487 ( OCLC )


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The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source

site maintained by the Florida
Cooperative Extension Service.

Copyright 2005, Board of Trustees, University
of Florida

Agronomy Research Report AY 77-1 September 1976

Department of Agronomy ., 'J
Agricultural Experiment Station, IFAS '"'l, I .l-
University of Florida v-il
Gainesville, Florida 32611


0. C. Ruelke "- f" 'e;- f
Bermudagrass, Cynodon dactylon (L) Pers., an improved pasture grass

grown in many areas in Florida, can be found throughout most of the

tropical and subtropical parts of the world. Although its origin is

thought to be in India, there is a much greater diversity of types of

bermudagrass found in Africa, therefore it is possible that Africa

rather than India is the primary center of origin. Recently, selections

from African introductions have been released as cultivated varieties or

are being used in breeding new varieties.

The purpose of this research was to evaluate some of the new var-

ieties as well as some which are being considered for release as new


Experimental Conditions
A series of field trials were initiated on an upland Arredondo

loamy fine sand site on the Agronomy Farm at Gainesville, Florida to

evaluate new and existing varieties for cold tolerance, dry matter

yield, digestability and yield of digested organic matter as well as

other forage properties. Each of the entries was grown in plots 6 ft x

18 ft and were separated by a 6 ft clean-tilled alley to prevent mixing.

This public document was promulgated at an annual cost
of230.85dollars, or.23e cents per copy, to inform
farmers, county agents, and seedsmen of research re-
sults with bermudagrass varieties.

A randomized complete block experimental design with four replications

was used in each evaluation trial.

During 1975 each of the plots received a total of 300#/A of nitrogen,

split into 5 equal applications of 60# each, which was supplied from a

17-5-10- fertilizer with 20#/T of FTE 5U3 added. A 2.5X15ft strip was

harvested with a plot mower at a stubble height of three inches at five

week intervals after the initiation of new growth in the Spring. Yields

were calculated on an oven-dry, pure bermudagrass forage basis.

Samples of forage were analized for in vitro organic matter di-

gestion. Fresh samples were analized for levels of hydrocyanic acid


Results and Discussion

Performance data obtained from experimental plots established on

July 7, 1974, are shown in Table 1. The highest total yield of dry

matter was obtained from Hybrid 72-81, which was obtained from Dr. G. W.

Burton at Tifton, Georgia and is the cross (Coastal X Kenya 61) X Berlin.

This is one of a series which is being developed for superior yield,

digestability and cold tolerance. This comparison also included other

varieties selected for cold tolerance including Coastal, Midland and

Alicia. It was noted that early season yields of Alicia were similar to

Coastal while late season and total yields of Alicia were substantially


The highest in vitro organic matter digestion percentage was ob-

tained from Coastcross-1 with several giant type bermudas such as Wonder-

grass, Callie and Mc Calebs slightly more digestable than Coastal.

Alicia had the lowest percentage of IVOMD of those tested.

Taking into account yield, percentage of organic matter and per-

centage of in vitro organic matter digestion, the highest production

was obtained from Callie giant bermudagrass followed by Hybrid 72-81 and


Average performance data from the harvests made September 9 and

October 23, 1975, from experimental plots established on June 26, 1975,

are shown in Table 2. The highest average yield per cutting was ob-

tained from Callie giant bermudagrass with similar high yields from each

of the giant bermuda or stargrass types of grasses.

The highest percentage of in vitro organic matter digestion was

obtained from Hybrid 74-68, a hybrid being developed by G. W. Burton at

Tifton, and selected for high digestability. During the early estab-

lishment, hay harvested from the giant or stargrass types were as high

or higher in digestability than Coastcross-l. The high levels of in

vitro digestion along with high dry matter yields resulted in higher

yields of digested organic matter of the giant or stargrass types,

with Callie bermudagrass producing the highest yield of digested organic

matter. The ability to establish rapidly and compete vigorously has

enhanced the value of these grasses, especially where encroachment of

bahiagrass and common bermudagrass occurs.

lhe presence of hydrocyanic acid, HCN, in stargrasses has been re-

ported in the literature for some time. A loss of cattle due to cyanide

poisoning was reported in Florida in 1975. Methods for evaluating HCN

levels in bermudagrass are being evaluated. HCN ratings are shown in

Table 2. Ratings of high to very high are considered to be dangerous to

very dangerous for grazing, based on earlier work with sudangrass. These

data indicate that Sumner and Wonder varieties can be very dangerous for

grazing and that several other stargrass type grasses may vary from low

to high levels of HCN. To date, levels of HCN in Callie have been found

to be low.

Summary and Conclusions

Based on 1975 data, it appears that Coastal bermudagrass can be

recommended throughout Florida. Coastcross-1 is more digestable than

Coastal and, without severe cold damage, will produce more digested

organic matter. Callie giant bermuda produces a higher yield and di-

gestability is intermediate between Coastal and Coastcross-l. Several

new hybrids, namely Hybrid 72-81 and Hybrid 74-68, show promise for the


All present data indicate that Alicia is less digestable and less

productive and that Sumner and several other stargrass types can be

toxic to animals.

The author would like to express appreciation for the valuable as-

sistance obtained from Drs. J. E. Moore, G. 0. Mott, V. N. Schroder, F.

T. Boyd, E. M. Hodges and all the laboratory and field technicians in

gathering this information.

Table 1. 1975 Performance data
upland sand on the Agronomy Farm

of bermudagrass varieties grown on
at Gainesville, Florida.







Hybrid 72-81



Mc Calebs


Dry matter






















Dig. 0. M.











fc ^

Table 2. Average performance of late 1975 harvests of bermudagrass
varieties, in the year of establishment, grown on upland sand on the
Agronomy farm at Gainesville, Florida.

Variety Ave. Tons/A/cut % Ave Tons/A HCN
Evaluated Cut late 1975 IVOMD Dig. O.M./Cut Ratings

Coastal .62 54.30 .31 V. Low

Coastcross-1 .96 61.55 .54 Low

Hybrid 74-68 .98 64.12 .58 V. Low

Callie 1.55 61.48 .87 Low

Sumner 1.28 61.38 .72 V. High

Wonder 1.26 60.57 .71 V. High

Mc Caleb .95 58.37 .51 M-H

Ethiopian 1.19 62.68 .68 L-M

Rhodesian 1.38 61.29 .78 L-H

Sarasota .69 56.64 .36 L

Afrograss .55 53.09 .27