Differential Variability and Stability of Cocoa Clones to Varied Rootstock ages of Patch Budding
Adewale1, B. D., Nduka2, B. A., Adeigbe1, O. O. and Taiwo3 N.
Journal Title:Journal of Chemical, Biological and physical sciences
The probability that Cocoa genotypes may exhibit different physiological
variation when used as scion on the same clonal rootstock of different ages had necessitated
the present investigation. Rootstocks were raised from open-pollinated pods of F3Amazon
for the ages of one, two and three months. Budwoods from five genotypes were patch
budded on the common rootstock of different ages. Growth and development of the budded
materials were monitored for four months. The seedling length, girth and the number of
leaves per plant of the rootstock at the three ages differed significantly (P ? 0.001). The
oldest seedling had the highest significant (P ? 0.05) mean of twelve leaves; 36cm seedling
length and 0.51cm stem girth. After budding, DAH, FW and LA exhibited significant (P ?
0.01) genotypic variation. The three ages differed significantly (P ? 0.001) for FW. The only
variable with significant (P ? 0.05) clone by age interaction was PDM. Broadsense
heritability was quite low (< 23%) in FW, DW and PDM; however, DAS, DAH and LA had
59, 71 and 85% respectively. With respect to PDM, the five clones performed differently in
response to the three ages of the root stock. Shukla stability variance and Wricke
ecovalence agreed and uniformly identified CRINTc-2 to be most stable genotype across the
three ages at budding. The PDM performance of other genotypes is rootstock-age specific.
The understanding of the interaction of clones with different rootstock ages in the patch
budding or grafting protocols may greatly enhance wider production of cocoa clones.