Table 19.


Comparison of laboratory analyses of rodent-damaged and
undamaged sugarcane samples (values given are averages).


Analysis Damaged sample Undamaged sample

Total solids 18.17% 20.20%

Sucrose content (juice) 15.60% 18.50%

Puritya 8619.4, 9136.1

Sucrose content (cane) 11.20% 13.20%

Expected yield 8.95% 10.95%

Glucose content 5.42% 1.47%

Reduced sugarsb 0.985% 0.258%


a Purity is expressed as a
solids.


ratio between


sucrose content and total


b Types of sugars that are considered undesirable.


These results clearly show that rodent damage adversely
quality and yield of sugarcane.


affects the


We have information about severe damage to newly planted sugarcane in
Argentina. The species responsible was not identified as to genus or
species, but it is known to be a neotropical rodent.

With respect to Mexico, rodent damage is considered one of the factors
most responsible for low production of sugar. In the area of
Veracruz, rodent damage is permanent and relatively stable. This is
contrary to what occurs in rice where, up to now, evidence points to
the existence of a 3- to 5-year population and damage cycle.

Rice seems to be the crop most affected by rodents in Latin America.
In most instances, rodent damage in rice appears to be cyclic in that
rodent populations reach very high numbers in some years. Rice
farmers in Venezuela reported very high rodent populations and damage
in 1971; this occurred again in the crops of late 1976 and early 1977.
(Note: DWRC biologists observed similar population eruptions and