PRELIMINARY STUDY TO CONTROL FLOWERING BY TRUNK GIRDLING AND PACLOBUTRAZOL TREATMENT IN LONGKONG
The study was carried out to determine a practical method for controlling off-season flowering of Longkong (Aglaia dookkoo Griff.), which is a major fruit tree crop in the humid climate of tropical southern Thailand. The study was carried out with 10-15 year-old longkong trees grown in 1×1×1 m3 container and in the orchard. Both growing conditions were four treatments including: (1) control, (2) trunk girdling, (3) paclobutrazol (0.4 g of 10% a.i./tree as soil drench) and, (4) trunk girdling + paclobutrazol. In the container experiment, flower buds burst in three weeks among all treatments. The highest flowering was found in treatment of trunk girdling and paclobutrazol used alone and higher than using in concomitant trial and control, respectively. In the 5th week, the unexpected result was that growth of flower buds in all treatments ceased to develop and finally they dried. In the orchard experiment, the burst of flower buds was seen within two weeks after treatments. At the 16th week, trunk girdling and paclobutrazol of all treatments encouraged more flower bud bursting than control, which only produced 1.5 flower buds. The efficiency of the concomitant trial was better than girdling and paclobutrazol alone, it was 31.5, 11.5 and 6.8 flower buds, respectively. Furthermore, paclobutrazol application had a side effect of retarding flower bud growth. In conclusion, the suitable method for controlling flowering in longkong may be associated with tree stage and growing conditions of drought stress and carbohydrate accumulation. These possible assumptions will be discussed along with the results.
Lerslerwong, L., Tipparn, S. and Chanaweerawan, S. (2014). PRELIMINARY STUDY TO CONTROL FLOWERING BY TRUNK GIRDLING AND PACLOBUTRAZOL TREATMENT IN LONGKONG. Acta Hortic. 1024, 211-216
off-season flowering, gibberellin inhibition, floral induction, flower buds burst, trunk girdling