ISHS Acta Horticulturae 665: II International Symposium on Lychee, Longan, Rambutan and other Sapindaceae Plants
EFFECT OF POTASSIUM CHLORATE, POTASSIUM NITRATE, SODIUM HYPOCHLORITE AND THIOUREA ON OFF-SEASON FLOWERING AND PHOTOSYNTHESIS OF 'DO' LONGAN |
| Authors: | C. Sritontip, Y. Khaosumain, S. Changjaraja, R. Poruksa |
| Keywords: | flower emergence, terminal bud break, soil drench, foliar spray, CO2 assimilate rate |
| Abstract:
The effects of potassium chlorate (KClO3), potassium nitrate (KNO3), sodium hypochlorite (NAOCl) and thiourea on off-season flowering and photosynthesis of ‘Do’ longan were studied using 4-5 years old longan trees at Lampang Agricultural Research and Training Center. The treatments comprised of soil drenched with KClO3 at 5 g.m-2 of canopy, foliar spray 1,000 ppm of KClO3, foliar spray 25,000 ppm of KNO3, soil drenched with NAOCl at 50 ml.m-2 of canopy, foliar spray 5,000 ppm of thiourea and untreated trees. The results showed that the soil drench and foliar spray of the KClO3 treatments had the highest percentage of flower emergence. The KNO3 and thiourea treatments had the highest percentage of leaf flushing. The KClO3, KNO3 and NAOCl treatments showed the least time of terminal bud break comparing to the thiourea treatment and untreated trees. The efficiency of photosystem II (Fv/Fm) at the 1st week before terminal bud break, the net CO2 assimilate rate at the 1st week before terminal bud break and the net CO2 assimilate rate at during terminal bud break of the plants treated were with KClO3, KNO3 and NAOCl were higher than the plant treated with thiourea treatment and untreated trees. The soil drench of KClO3 and NAOCl induce the highest net CO2 assimilate rate at the 1st week after terminal bud break period. The transpiration rate of all treatments were not significant different and the thiourea treatment showed the least stomata conductance in the 1st week before terminal bud break. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
