THE RESPONSE OF LONGAN TREES TO TRAINING SYSTEM AND FERTILIZER MANAGEMENT

Abstract

The response of longan trees to 4 training shapes and 2 fertilizer application rates was studied over 2 years. The 4 training shapes were; untrained (half sphere), open canopy, cube like and flat. The 2 fertilizer application rates were the replacement and twice the amount of crop removals rates. The study was conducted on the 12-year-old longan trees cv. 'E-daw' grown on upland with a 6x6 m planting space. The results show that on the flat and cube like shapes trees flush faster and more frequency than the others. However, in both years, there was no difference in the percentage of flowering in all tree training shapes. The flowering was 96.3% or higher. The flat shape trees produced the lowest yield in the first year. In the second year, there were no differences in yields among treatments. The cost of production of the flat shape trees was the lowest in both years. Fruit size and the average gross and net profit were highest in the cube like shape trees. There no significant difference between the two fertilizer application rates and the interaction with the training shapes.