Galactia striata (Jacq.) Urb.

Glycine striata Jacq.; Glycine velutina Bert.; Galactia cubensis H.B.K.; Galactia berteriana DC.; Galactia brevistylla Schlecht.; Adonia refusa Rose.

Galactia (Brazil), Frijolillo (Panama).

A slender, much branched, very variable, twining, climbing perennial legume with stems to 1.5 m long or more. Three leaflets, rounded to obtuse, acute at the tip, 2 to 8 cm long, central leaflet larger than the laterals, slightly more densely puberulent below than above. Stipules lancedeltoid, caudex about 1 to 1.5 mm long. Petioles 1.5 to 3 cm long. Racemes slender, 1 to 24 cm long, flowers from bright pink fading bluish or mauve to purple, few, subsessile to pedicels 1 to 2 mm long. Calyx 4 to 5 mm long, densely puberulent. Petals 8 to 10 mm long. Pods 4 to 7 cm long, 4 to 9 mm wide, narrowly marginate when mature, minutely and moderately puberulent, elastically two valved. Kidney-shaped seeds, 3 to 4.5 mm long and about 2 mm wide, dull black to mottled pinkish brown (Shreve and Wiggins, 1964; Adams, 1972).

Native from Mexico south of Sonora State and most of Central America to the West Indies, south through Venezuela to Minas Gerais, Brazil.

Galactia nodulates well, with large spherical nodules scattered along the lateral roots. On cerrado soils in Brazil, the addition of 75 kg./ha N at planting as well as inoculation with commercial inoculum produced the highest galactia yields (Vargas and Suhet, 1981).

In haymaking trials in Brazil, galactia and centro were the fastest drying of the nine legumes tested. While galactia green matter had a high leaf to stem ratio, it lost the most leaves during haymaking (de Moura et al., 1975). At San Miguel, Brazil, it was studied for silage-making together with centro, siratro and glycine. It was concluded that none were really suitable for silage making, ensilage could only be made by wilting at an early stage of growth and that the addition of a preservative, with a high sugar content, would be required to produce a good quality silage (Tosi et al., 1975).

Galactia has been tested as a standover dry season forage on a red-yellow latosol in the Brazilian cerrados. It was considered to have considerable potential for this purpose. It has better dry-season growth than most alternative species and apparently retains its quality better as a result. Yields available in the critical August-September period over two years ranged from 1 000 to 5 000 kg./ha dry matter depending on the date grazing was deferred and the year. Leaf contributions to the dry matter decreased from an initial 75 percent to about 35 percent 168 days after deferment of grazing began (Vera et al., 1983).

In the Brazilian deferment study, crude protein over the dry season averaged 15 percent in the standing herbage. The crude protein content of the leaves dropped from 32 percent at 28 days of age to about 20 percent at 112 days and then remained constant. In the stems, it was 15 percent initially, stabilizing at 10 percent at 84 days. The in vitro dry-matter digestibility of the available forage fell slowly over the dry season, being in the order of 55 to 60 percent over the most critical period. In vitro dry-matter digestibility of the leaves stabilized around 65 percent after 56 days (Vera et al., 1983) .

A promising legume, native to and being widely tested in South America, especially in Brazil. It has performed well on deep, latosolic soils at Nova Odessa in São Paulo State where it has yielded better than siratro, stylo and centro. Also at Nova Odessa, a guinea grass/galactia mixture yielded as much as guinea grass by itself fertilized with 180 kg./ha of N. Siratro, stylo and centro produced yields ranging only from 40 to 90 kg./ha N when mixed with guinea grass in the same trial. Crude protein, phosphorus and calcium yields were higher for guinea grass combined with any of the four legumes than for guinea grass by itself fertilized with 225 kg./ha N (de Mattos and Werner, 1979).
Galactia has also equalled siratro and outyielded centro and glycine over four years in Herculandia and Sao Manuel in Brazil (Tosi et al., 1979), while in five locations in Ceara State, galactia, siratro and Clitoria ternatea were able to survive the dry season, had high nutritive values and resistance to pests and diseases and produced a large amount of dry matter and seed when sown into native pasture (Gurgel and Fernandes, 1980). At Felixandria, Minas Gerais galactia was among the highest yielding of eight legumes tested, together with siratro and common stylo, giving a fourfold increase in wet-season pasture yields and higher dry-matter yields and P concentrations over the dry season than the native pastures (Andrade, 1981). Galactia is being studied as a native legume also in Costa Rica (Perez-Guerreroz, 1980). It is adapted to the well-drained savannah ecosystem in Colombia (CIAT, 1979).

De Mattos and Alcantara (1976); Vera et al. (1983); Perez-Guerreroz (1980).

Additional Information by Dr. P. Izaguirre de Artucio