Bwa-yo - Société Audubon Haiti

138 Nim
Table 16.1 Proximate analysis (% dry weight) of A. indica, after Gohl(1975).
COMPONENT CRUDE CRUDE CRUDE CARBO- ASH Ca P
PROTEIN FIBER FAT HYDRATES
Fresh leaves (India) 15.4 12.7 4.2 56.5 11.2 2.65 0.24
Fresh leaves (Pakistan) 13.4 14.7 6.2 55.5 10.3 1.94 0.17
leucostica or C. meliae (Tourigny, 1987), under humid or poorly-ventilated conditions;
a "carrot top" foliar disease ofuncertain cause; and leaf chlorosis caused by using potting
medium contaminated with nematodes (Josiah, 1989; Runion et aI., 1990).
Seedlings normally require 14 weeks in a Rootrainer or Winstrip prior to outplanting,
with the initial 4 weeks under shade and the last 4 weeks reserved for hardening off.
There are several alternative propagation methods that are less costly and simpler
than the containerized seedling. The two methods that are the most practical for neem
is stump propagation and the transplanting ofvolunteers from beneath selected mother
trees. Stumps are prepared by raising seedlings directly in a raised bed and pruning both
stem and roots prior to outplant. Reid (1991) .showed· no differences in survival or
growth between stumps and containerized seedlings at 2 sites in Haiti following a year
of growth. Volunteers are lifted from beneath selected mother trees and transplanted
during the rains. A portion of the lifted seedlings are rejected because of natural root
deformities associated with looping and poor vigor. One study revealed that up to 22%
of the volunteers had root deformities, while 39% had excellent taproot formation
(Larson et aI., 1985). While transplanting volunteers increases mortality rates and poorer
root development, the trade-off has to be measured in terms of the economics and
practicality'ofmanaging a containerized nursery under typical Haitian farm conditions.
Seed Handling: One of the most serious limitations in artificial propagation is the
problem ofseed longevity and adequate germination procedures to test seed viability.
Howeve.r, neem seed may be stored successfully up to 4 months if the seed is dried
immediately following harvest in the sun for 3 days and stored in cotton bags at 15° C
at reduced levels ofhumidity (Chaisurisri, 1986). Seed can be stored for longer periods
of time if moisture content is lowered to 6.6-7.3% (dry weight basis) and stored continuously
in sealed containers at 4°C. Furthermore, dormancy factors associated with
the seed hull must be overcome to maximize germination capacity. Removal ofthe seed
coat has shown a 10-fold increase in germination ofstored seed in Haiti (Timyan, 1991).
Similar results were shown for 2 seed lots from Africa: 2-year-old seed germinated 24%
compared to 62% with the endocarp removed, while 8 1h-year-old seed exhibited differences
of 20% and 70% (Bellefontaine and Audinet, 1993).
Azadirachtin Levels: Azadirachtin levels in neem seed were analyzed for tree andseed
maturity effects in 1989 (Timyan and Walter, 1990). This study was initiated based on
reports from W.R. Grace & Co. that certain seed lots from Africa tested 2- to 10-fold
higher than seed lots from Haiti. It was suspected that both genetic and environmental
effects contributed to this difference. No differences were detected between 3 levels of
seed maturity, ranging from green seed on the tree and fallen seed on the ground.
However, differences were detected among trees, sites, and seed collected during different
seasons. There is reason to believe that even with the narrow genetic base that is