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Bahiagrass*
was not mentioned as a turf in 1929 by Enlow and Stokes and received little research
attention until the late 1930's. In 1938 Escambia, Florida County Agent E. H. Finlayson
discovered what would be called 'Pensacola' bahiagrass (Paspalum notatum
Fluegge var. saurae Parodi) (Parodi, 1948) on a sodded sand bank (Finlayson, 1941).
This excellent growing plant may have arrived as a stowaway on a fruit boat from Central
or South America (Hanson, 1972). It was released in 1944. Burton (1946) discovered
'Pensacola' is diploid (2n = 20) and reproduces sexually based on variable progenies
(Burton, 1955). Native to eastern Argentina (Quarin et al., 1984), the Pensacola cytotype
has become one of the major forage grasses of the southeastern United States (Burton,
1967). It is planted extensively from seed along highways in Florida, North Carolina, and
other subtropical and mild temperate areas. Pensacola is more cold tolerant than
tetraploid bahiagrass cultivars.
The tetraploid bahiagrass cytotype P.
notatum var. latiflorum Doell (2n = 40) is the most common botanical variety
in tropical and subtropical America (Parodi, 1948). It has considerable variability
(Fernandes et al., 1973) and includes several broad-leafed cultivars, such as 'Argentine',
'Paraguay-22', and 'Wilmington'. The former is widely used in lawns and for solid sodding
on highway embankments and the 0.8 m edge along the pavement. Argentine has broader leaf
blades than Pensacola, yet it is superior as a turf because of its more prostrate, denser
appearing growth habit. This violates the usual precept that finer textured cultivars are
superior turf types. Argentine was released in 1950 by the University of Florida as a
pasture grass (Killinger et al., 1951). It had been introduced from Argentina in 1944 as
P.I. 148996. Naturally occurring, tetraploid bahiagrasses are always obligate apomicts
(Burton, 1948). Breeding improvement has to be either clonal selection, or else must cross
the reproductive barrier by the use of artificially created tetraploids which are sexual
(Burton and Forbes, 1960). The F2's from sexual X apomictic crosses shows that apomixis in
tetraploid bahiagrass is mostly recessive.
The main turf use for bahiagrass is for
large turf areas. Soil erosion is considerably reduced. In the Republic of China
continuous bahiagrass cover reduces annual soil loss from 1.56.104 g m-2 (with clean
culture) to 1.5.102 g m-2 (Jean and Juang, 1979). Bahiagrass turf requires little or no
irrigation, even in well-drained sands, requires minimal fertilization, 5 to 10 g N m-2
y-1, and has few important pest problems, e.g., Scapteriscus mole crickets. The use of
bahiagrass for turf has often been discounted, yet in 1974 it was the principal turfgrass
of Florida (Anonymous, 1976). Unfortunately, bahiagrass grows poorly in areas with
moderate or heavy shade. It produces abundant seedheads for a brief period (mostly about 6
weeks in summer), but some seedheads occur sporadically throughout the growing season.
Bahiagrass managers recognize the species to be difficult to keep mowed. The seedheads
typically reach about 0.7 m height.
Seed production is meager (225 to 350 kg
ha-1 would be the high range, W. R. Cook, personal communication) and seedling
establishment is often poor. Because of its slow vegetative growth rate (Busey and Myers,
1979) and open growth habit, bahiagrass is susceptible to weed invasion, particularly in
the seedling stage. Better management can correct establishment problems of bahiagrass
(Busey, 1992). A Rapid Coverage Polycross (RCP-1) population was developed in Florida for
possible cultivar release (Busey, 1989).
The seedhead problem has been evaluated
for possible reduction through selection. Efforts have been made to develop a dwarf,
turf-type bahiagrass (Hanna and Burton, personal communications; Busey, 1985; and Busey,
1989). No selection appears to have been done towards lessening the shade sensitivity of
bahiagrass. Scapteriscus mole crickets screening yielded inconclusive results (Busey and
Reinert, unpublished). This pest damages turf mechanically while foraging, much as a
rototiller would damage turf, and in some cases the turf is not the host. Thus it may be
unfeasible to develop mole cricket resistant cultivars. The majority of research on
bahiagrass improvement continues to be for forage. This includes work in Japan (Sakai,
1983), the United States (Burton, 1982), and Zimbabwe (Mills and Boutwood, 1978).
Bahiagrass cultivars have not been
developed specifically for turf, yet the recognition of cultivars for pasture and
conservation has satisfied some turf needs. A major concern in the development of any
turf-type bahiagrass is whether seed producers will accept it. Bahiagrass seed is
traditionally a byproduct of the cattle industry. The production of seed of a new cultivar
on any existing bahiagrass area would entail a major difficulty in the eradication of
existing grass. An improved turf bahiagrass, to be successful, would need either to be
very competitive and useful as a forage, or it would need a potential market sufficiently
large to justify specialized turf seed production areas.
References
Anonymous. 1976. Florida turfgrass survey 1974. Florida Department
of Agriculture and Consumer Services, Tallahassee, FL.
Burton, G. W. 1946. Bahia grass types. Agron. J. 38:273-281.
Burton, G. W. 1948. The method of reproduction in common bahiagrass, Paspalum notatum.
J. Amer. Soc. Agron. 40:443-452.
Burton, G. W. 1955. Breeding Pensacola bahiagrass Paspalum notatum: I.
Method of reproduction. Agron. J. 47:311-314.
Burton, G. W. 1967. A search for the origin of Pensacola bahiagrass. Econ. Bot.
21:379-382. Burton, G. W. 1982. Improved recurrent restricted phenotypic selection
increases bahiagrass forage yields. Crop Sci. 22:1058-1061.
Burton, G. W. and I. Forbes, Jr. 1960. The genetics and manipulation of obligate apomixis
in Common bahia grass (Paspalum notatum Flugge). p. 66-71. In: Proc. 8th
Int. Grassland Cong., Alden Press, Oxford, G. B.
Busey, P. 1985. Selection for seedhead characteristics in bahiagrass. Agron. Abstr. p.
114. Busey, P. and B. J. Myers. 1979. Growth rates of turfgrass propagated vegetatively.
Agron. J. 71:817-821.
Busey, P. 1989.
Genotype selection and seeding rate in bahiagrass establishment. Transportation
Research Record 1224:40-45.
Busey, P. 1992. Seedling
growth, fertilization timing, and establishment of bahiagrass. Crop Sci.
32:1099-1103
Enlow, C. R. and W. E. Stokes. 1929. Lawns in Florida. Florida Agr. Exp. Stn. Bul. 209.
Fernandes, M. I. B. de Moraes, I. L. Barreto, and F. M. Salzano. 1973. Cytogenetic,
ecologic and morphologic studies in Brazilian forms of Paspalum notatum.
Can. J. Genet. Cytol. 15:523-531.
Finlayson, E. H. 1941. Pensacola--a new fine-leafed bahia. South. Seedsman, Dec. issue, 9,
28.
Hanson, A. A. 1972b. Grass varieties in the United States. USDA Agr. Hdbk. 170.
Jean, Shiuan-yuh and Tzo-chuan Juang. 1979. Effect of bahia grass mulching and covering on
soil physical properties and losses of water and soil of slopeland (First report). J.
Agric. Assn. China (Taipei) 105:57-66.
Killinger, G. B., G. E. Ritchey, C. B. Blickensderfer, and William Jackson. 1951.
Argentine bahia grass. Univ. Fla. Agric. Exp. Stn. Circ. S-31.
Mills, P. F. L. and J. N. Boultwood. 1978. A comparison of Paspalum notatum
accessions for yield and palatability. Zimbabwe Agric. J. 75:71-74.
Parodi, L. R. 1948. Gramineas Argentinas nuevas o criticas: 1. La variacion en Paspalum
notatum Fluegge. Rev. Argent. Agron. 15:53-61.
Quarin, C. L., B. L. Burson, and G. W. Burton. 1984. Cytology of intra- and interspecific
hybrids between two cytotypes of Paspalum notatum and P. cromyorrhizon.
Bot. Gaz. 145:420-426.
Sakai, K. 1983. New summer crop cultivars (I)--New cultivars registered in Ministry of
Agriculture, Forestry and Fisheries in 1983 fiscal year. Japan. J. Breed. 33:499-506.
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