Chapter 6


 FACTORS INFLUENCING YIELDS AND PRODUCTION:
 PHYSICAL AND TECHNICAL


Breeding, disease and climatic factors
 Research into the most suitable types of plants for West Indian conditions has been
undertaken by governments, by such organizations as the Citrus, Coconut and Banana
Boards, and by private businesses or their agents, such as the Sugar Manufacturers
Association.

 Considerable advances in improving sugarcane types have been made by the Central
Cane Breeding Station, run by the West Indies Sugar Producers Association (BWISA),
where attention has been given both to disease resistance and to increasing yields in the
various climates and soils of the different islands. These variations in soil and climate
have demanded specialised attention to each territory. In British Guiana, for instance,
there are alternating wet and dry seasons, and this makes two crops of quick ripening
varieties possible whereas other territories favour growth of canes taking longer to
mature.

 The recommendations of the Cane Breeding Stations are usually fairly promptly adopt-
ed. In Barbados for instance the B 37161 variety is being replaced by newer varieties
such as B 45154, B 4744 and B 47419. There have been rapid changes to more resistant
varieties when diseases have broken out in various islands.

 The BWISA has a dynamic approach to cane breeding and holds that an ideal variety car
only be vaguely formulated since cultivation conditions and disease conditions are chang-
ing most of the time. They consider that efficiency is likely to be improved in the future
mainly by varieties with increased sugar content in the present range rather than by high-
er yields in the fields.

 Thanks to the work of such organizations as the Central Cane Breeding Station, diseas-
es are not nearly such a limiting factor in sugarcane cultivation as in the cultivation of
most other commercial crops, but there have been some outbreaks of "leaf scald". The
loss from diseases has not been computed, but has probably only been marginal, taking
the area as a whole.

 Rainfall has a very important influence on the growth of sugarcane. The main sugar
cane areas of the West Indies range from Antigua with an average annual rainfall of
41.52 inches per year to British Guiana with an average annual rainfall in the principal


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