Inheritance of catechin and caffeine in tea [Camellia sinensis (L.) O. Ktze.

Abstract

Diallel designs are used in many breeding programmes because of the important genetic information they offer to
plant breeders. Eight biochemical traits of Tea (Camellia sinensis (L.) O. Kuntze) were studied to investigate the underlying
gene action, and estimate the general combining abilities (GCA) and specific combining abilities (SCA) of parents and crosses
using diallel mating system. There were significant (p less than 0.05) differences among the genotypes for all the traits under study.
The general combining ability (GCA) effects were significant for six of the traits, namely GA, EGC, Caffeine, ECG, EGCG
and total catechin implying that these traits are governed by additive gene effects. SCA on the other hand was significant for
EGC, Caffeine, EC, EGCG, and total catechin. Maternal effects were significant for EGC, EGCG and total catechin signifying
importance of the choice of female parents in breeding programmes targeting these traits. Non-maternal effects were present in
EGCG and total catechin. The study revealed that parents which would produce above average progenies for total catechins are
AHP S15/10 and EPK TN14-3. The best combiners for total catechins were EPK TN14-3 x TREK 6/8 and AHP SI5/10 self
This information, which has hitherto been lacking will be very valuable for tea breeding programmes targeting high black/green
tea qualities.