Browsing by Author "PANDURANGA GUNAGA, RAJESH"
Now showing 1 - 1 of 1
Results Per Page
Sort Options
ThesisItem Open Access GENETIC VARIATION FOR PHENOLOGY IN A CLONAL SEED ORCHARD OF TEAK (Tectona grandis Linn, f.)(UNIVERSITY OF AGRICULTURAL SCIENCES GKVK BANGALORE, 2001-08-13) PANDURANGA GUNAGA, RAJESH; VASUDEVA, Dr. R.To elucidate clonal variations for phenology and its association with low fruit product'O" among teak Clonal Seed Orchards (CSOs), a study was conducted in a 19 year old CSO for a period of 13 months at Manchikere. Yellapura forest division. Inter-clonal differences among 24 teak clones for all phonological initiation events were significant suggesting a strong genetic basis. Strong provenance effect on phenology was also observed. Clones from central and southern provenances were early in initiating flower buds, flowers and peak flowering than those from northern. An overlap index to calculate the flowering synchrony among clones was developed for the first time. Clones of different provenances showed asynchronous flowering while there was a higher synchrony among clones within a provenance. Hence simple geographical continuity of clonal origin could be considered as a thumb rule while selecting clones for CSO. Partial flowering synchrony among clones can potentially violate panmixis and hence all the assumptions of establishing a CSO. Matured non-flowering rametes within a teak clone can also reduce fruit production of a CSO. This trait was genetically controlled and clones derived from older ortets tend to have higher per cent of non-flowering rametes. In general, time of initiation for all phenophases showed higher broad sense heritability, suggesting that these initiation events were controlled by genetic factors. However, durations of all phenophases were environmentally regulated. The highest genetic gain was (27.78%) obtained for time of leaf flush initiation. Clones that initiated leaf flushing early and possessed longer peak-flowering duration tend to produce higher number of fruits per inflorescence. Hence these two traits should be considered while selecting trees for CSO in order to increase the fruit yield. However, clones that coincide flowering with peak rainy days tend to show lower fruit set and hence should be avoided.