The Cayenne Pineapple — ^COLLiNS 
13 
MEAN NUMBER OF SLIPS PER PLANT 
Fig. 7. Ten Cayenne clones showing mean slip numbers for a period of 7 years, together with lowest and 
highest yearly means. 
ferences, the discovery of genetic variations 
(somatic mutations) which have an effect on 
slip number is more difficult than locating 
mutations which are not subject to environ- 
mental modification. However, by repeated 
tests under similar environmental conditions 
it has been possible to demonstrate the oc- 
currence of mutations affecting number of 
slips in this variety. 
Figure 7 shows the mean number of slips 
per plant for 10 clones over a period of seven 
plant crop harvests, together with lowest and 
highest limits of the yearly means for that 
period. Five of the clones had a range of 
annual mean slip number which did not over- 
lap the range of three other clones. Two 
clones, E and G, had a range of variation 
which overlapped all the other groups. There 
can be little doubt about a genetic difference 
existing between any one of the three high slip- 
producing clones, H, I, J, and any one of the 
five low-producing clones, A, B, C, D, and F. 
The three high slip-producers, H, I, and J, 
do not appear^ to differ among themselves. 
Clone G, overlapping in its range with both 
the high and low slip producers, appears to be 
genetically different from both groups. 
These mutant clones can be compared with 
each other, but should not be compared with 
the mean of the variety, first because they are 
a part of the variety and second because — the 
variety being a mixture of genetic types — 
random samples would not always include 
the same distribution of variant types. Fur- 
thermore, most Cayenne populations include 
some plants of the collar-of-slip strain, which 
produces a very high number of slips. 
The somatic mutations in Cayenne include 
a range of types varying from those having 
These conclusions are based upon another repli- 
cated plot test which showed significant differences as 
listed here, and we presume that the causes of the 
differences were genetic. 
