In the first trials on practical application, 123 out of 608 bear-
ing palms died of hartrot in the period from 1975 to 1979. The
treatments were started in early 1979, and there were no new
cases after the end of that year.
 In the second trial with 240 coconut palms, the hartrot in-
cidence was as follows:


Year
1981
1982
1983
1984


Number of trees
died of hartrot
 39
 15


Nil


 In this case, the treatment was started late in 1981 and was con-
tinued when a fresh case was noticed. As the results indicate,
there was a sharp decline in the incidence of hartrot after the
commencement of the treatment and finally the disease disap-
peared.
 In the third trial in a cultivator's field, the results were as
follows:


fected palm. Thus, the amount of the insecticide used and the
number of times applied is very much reduced. This saves both in
the cost and risk involved. Similar results have been reported for
oil palm in Colombia, where a combination of weed control and
insecticide spraying reduced 'Marchitez sorpresiva' from 53%
(control) to 2 %, while weed control alone reduced the disease in-
cidence to 13% and insecticide application alone to 35% (Mena
et al., 1975).

CONCLUSION
 Although these results are of special significance at this junc-
ture, research must be continued to identify safer methods and
chemicals which can be used to control the disease. Further
research must be able to specify cultural and serological methods
for identification of the pathogen, determination of the vector(s)
and proof of pathogenicity through Koch's postulates.


Month
Until
January 1983
February '83
March '83
April '83
May '83
June '83
July '83
August '83
September '83
October '83
November '83


Number of
trees affected

 8
 2
 1
 6
 5
 6
 3
 5
 6
 2
 Nil


 Thus of 398 bearing palms, 44 (11%) were lost due to the
disease through October 1983. Nine months after commencing
the treatment in February 1983, the disease ceased to occur in
that field.
 In the fourth trial, in an experimental field using 280 four-
year-old palms, the disease first started in August 1983 on one
tree and the first treatment was given. In March and April 1984
two and one more palm were affected respectively, and the treat-
ment was repeated. Since then there were no new cases.


Acknowledgement
 Thanks are due to Mr. M.A. Palmtak for his invaluable assistance in the field.
 References
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Pentatomidae Discocephalinae and its possible role in the transmission of Marchitez
of oil palm and Hart-Rot of coconut. Olkagineaux 39(1):1-6.
 2. Drost, A.W. 1908. Jaarverslag over 1907. Insp. Landb. Surin. 19-20.
 3. Eden-Green, S.J. 1978. Rearing and transmission techniques for Haplaxius
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PROCEEDINGS of the CARIBBEAN FOOD CROPS SOCIETY-VOL. XX