TY  - BOOK
AU  - Sridevi R 
AU  - Prasanna Kumari Amma S(Guide)
TI  - Estimation of Genetic Parameters from Specific Crosses of Cocoa (Theobroma Cacao L.)
U1  - 638.8 
PY  - 1999///
CY  - Vellanikkara
PB  - Department Of Plantation Crops And Spices,College Of Horticulture
N2  - The research project entitled 'Estimation of genetic parameters from 
specific crosses of cocoa (Theobroma cacao L.)' was carried outean ongoing 
experiment of Cadbury-KAU Co-operative Cocoa Research Project (CCRP), 
College of Horticulture, Kerala Agricultural University, Vellanikkara, Thrissur 
during 1998-99. The studies were conducted in four year old hybrids. The major 
objectives were to study the genetic variability, heritability, correlation of different 
traits with yield, extent of heterotic expression of various traits and to examine the 
association between seedling vigour and yield. Twenty five cocoa hybrids were 
maintained in randomised block design with three replications. 
The hybrids exhibited significant variability for most of the traits studied. 
The estimates of pev were higher than gcv for all the traits studied. The highest 
heritability was recorded for number of beans per pod and seedling vigour recorded 
as °HD2 (6 MAS) had a high genetic gain. Yield and number of pods per tree 
recorded moderate genetic gain. 
Yield was found to be significantly and positively correlated with number 
of pods per tree, height (2 YAP) and girth (2 YAP) of the tree. Absence of 
significant correlation between yield and seedling vigour was observed. Path 
analysis revealed the importance of pod number per tree and wet bean weight per 
pod in determining yield. 
Yield and number of pods per tree showed a very high heterotic 
expression in most of the hybrids. Among the 25 cross combinations H23 was 
identified as the superior cross combination followed by H16 and H; The parents of 
 
these cross combinations can be used for raising biclonal seed gardens, as they had 
a good specific combining ability. 
The floral traits did not vary markedly in the hybrids. However the 
qualitative traits exhibited wide variation in the different hybrids. 


UR  - http://krishikosh.egranth.ac.in/handle/1/5810103719
ER  -