Abstract
E. berteroana is widely distributed throughout lowland tropical dry forest from southern Mexico to northern Peru, and in the Greater Antilles. This species occurs naturally from low to mid-altitudes 300-600 m, however it has been planted up to the 1000 m. It grows in humid areas with an average temperature of 25.5°C and an average annual rainfall of 3500 mm. E. berteroana is important in agroforestry, for it replenishes the soil and fertilizes companion crops. This species is commonly used for live fencing from Mexico to northern South America (Russo, 1993). In Costa Rica it is also widely used for fence posts (Nygren, 1993). After pruning E. berteroana produces a great volume of large leaf shoots in only three to four weeks. Biomass production of E. berteroana living fence varied according to pruning frequency (CATIE, 1989a, 1989b). The fence produced the most woody biomass when pruned every 12 months, the least biomass when pruned every three months, and 6-month pruning produced the most edible biomass. Live fencing of E. berteroana can also provide cuttings for additional posts, and a vigorous tree can produce 10 or more cuttings of 5-15 cm diameter every two years. E. berteroana is not recommended as a shade tree because it has a fragile stem and does not provide enough shade. The leaves contain 40% crude protein, 4% nitrogen, and are commonly used as fodder for cattle, rabbits and goats (Russo, 1993). Unfortunately, leaf fall occurs in the dry season when forage is important because pasture quality decreases (Beer et al., 1989). Other uses of E. berteroana are, windbreaks, dyes, insecticides, poles to grow crops such as black pepper, Piper nigrum, Dioscorea alata (yam), Sechium edule or Passiflora ligularis (granadilla). This species also forms a useful mulch for annual crops such as maize (Russo, 1993). This species may be used for fuelwood and construction, although the timber is not used extensively because it is light, coarse, unattractive and lacks durability. The stem bark of E. berteroana contains a prenylated flavanone. This compound has an anti-fungal activity against Cladosporium cucumerinum (Russo, 1993). In El Salvador the bark of E. berteroana is used to poison dogs and wild animals. E. berteroana is a fast growing species, and is easy to propagate by seed layering, marcotting, cuttings, and particularly large stakes more than 2.5 m long. The stakes are usually cut at the end of the dry season or the beginning of the rains. They may be planted immediately, or stored vertically or laid individually on the ground for up to two weeks in a cool, shady place (Viquez, 1993). Flowering occurs October-February and fructification between May-June. The species produces large quantities of red beans every year, a kilogram of seed contains 3000-3500 seeds. The seed is orthodox, and has a hard, impermeable seed coat and should be scarified either with sandpaper, a knife, or soaking in warm water (40°C) for 12 hours, to aid germination. E. berteroana has germination rates of 85-90%, when using seed collected from the previous year which has been stored in cold chambers at 5°C with a relative humidity of 30-40%. The shoot borer Terastia meticulosalis has been observed on E. berteroana. Damage can be critical in newly sown agroforestry plantings, there have been reports of serious attacks on small trees (generally those less than 1.5 m tall) associated with black pepper. The adults of Phyllophaga menetriesi feed on the young foliage of this species.
Germination and vigor of Caesalpinia pulcherrima (L.) Sw. seeds under different light and temperature conditions
