Bwa-yo - Société Audubon Haiti

128 Lisina ••• Delen
28 MONTH YIELD (DRY KGIM)
12r-------------------------,
10
6
4
2
• LEAF AND WOOD < 1 eM
8.2
WOOD>ICM
o LELE LED! GLSE 6287 GLSE MEAN
ALLEY CROPPING SPECIES
Figure 15.10 Dry yield of subspecies glabrata (LELE) compared with 1. diversifolia
(LEDI), the highest-yielding -Gliricidia sepium (GLSE) provenance, 6287, and the average
of 20 G. sepium provenances.
though both were 2-3 times more productive than the top G. sepium accession. With
regard to wood> 1 cm, subspecies glabrata yielded higher than 1. diversifolia subsp.
diversifolia. Both species exhibited more than twice the wood yield ofthe top G. sepium
accession. Cunard (1991) conducted fresh biomass measurements of2 harvests in a
direct-seeded hedgerow trial near Camp Perrin. He did not find subspecies glabrata to
be superior to Calliandra calothyrsus, though both were more productive than 4 other
legumes, including G. sepium. He measured total fresh yields of about 1 kg m- I after 5
months of coppice growth for 1. leucocephala subsp. glabrata. Other hedgerow trials
have confirmed the broad adaptability of 1. leucocephala subsp. glabrata, usually
ranked at the top until one reaches the upper elevations (Isaac et aI., 1994). The hybrid,
KX3, is showing comparable yields with subspecies glabrata and may be better adapted
to sites above 1000 m than either of its parent varieties. Dry yield estimates for
Leucaena species in hedgerow/alley cropping designs are summarized in Table 15.4.
Tree Improvement: A recent status of a network of seed-production areas and treeimprovement
trials involving subspecies glabrata is given in Timyan (1993). The introduction
of the subspecies to Haiti in the latter part of the 1970s was most probably of
narrow genetic base, representing the self-pollinated K8, K28 and K67 isolines from the
University of Hawaii.K8, the most widely cultivated variety, originally was collected
from one -or a few cultivated trees in the northern Mexico state of Zacatecas in 1959
(Hughes, 1993). Though the Asian psyllid epidemic ofthe mid-1980s did not happen in
Haiti, the indiscriminate distribution ofsuch a narrow genetic base is risky. The continued
improvement ofLeucaena in Haiti requires the importation ofa wider genetic base
than that which was introduced in the late 1970s. It was not until 1985 that another