A relationship between flowering and forking in teak (Tectona grandis) has been postulated for decades, prompting calls for genetic selection to delay flowering time. Teak flowers develop on terminal panicles in the upper crown, causing bifurcation of the stem or branch. When flowers are initiated on the main stem, vegetative growth is stalled and a fork will occur unless apical dominance is recovered rapidly.
Until now there have been few data to quantify the relationship between forking and flowering of teak. However, I have a paper in press with Canadian Journal of Forest Research that will shed further light on the picture. The study was based on a cloned progeny trial of Thai provenance material to quantify the phenotypic and genetic relationships between flowering age, forking age, and forking height.
Forking height and forking age were under weak to moderate genetic control. Flowering age was under substantially greater genetic control with narrow-sense heritability of 0.21 and broad-sense heritability of 0.46. The most exciting result was that additive and non-additive genetic correlations between forking height and flowering age were estimated to be 0.84 and 0.55, respectively. Improvement of forking height was calculated to be almost twice as efficient by indirect selection on late flowering.
Until now there have been few data to quantify the relationship between forking and flowering of teak. However, I have a paper in press with Canadian Journal of Forest Research that will shed further light on the picture. The study was based on a cloned progeny trial of Thai provenance material to quantify the phenotypic and genetic relationships between flowering age, forking age, and forking height.
In conclusion, there appears to be strong evidence at least in this population for selecting on late flowering in teak to improve bole length. I will post details of the paper when it is published on line.
RSS Feed