%A SONG Juan-, CHEN Mao-Sheng-, LI Jia-Long-, NIU Long-Jian-, XU Zeng-Fu %T Effects of Soilapplied Paclobutrazol on the Vegetative and Reproductive Growth of Biofuel Plant Jatropha curcas %0 Journal Article %D 2013 %J Plant Diversity %R 10.7677/ynzwyj201312086 %P 173-179 %V 35 %N 2 %U {https://journal.kib.ac.cn/CN/abstract/article_33135.shtml} %8 2013-03-25 %X

Multipurpose plant Jatropha curcas seeds contain about 40% oil, which is a promising energy plant for producing biofuels. Jatropha plants, especially those grown in tropical areas, show excessive vegetative growth, and erratic flowering and fruiting, which result in the low seed yield observed. This study was undertaken to determine the effects of plant growth regulator paclobutrazol (PAC), an inhibitor of phytohormone gibberellin biosynthesis, on the inhibition of vegetative growth, and the promotion of reproductive growth of Jatropha. The results showed that soil application of PAC with an appropriate dose (0.8g·m-1 canopy diameter) inhibited shoot growth, reduced plant height, and promoted reproductive growth of Jatropha. The number of flowering and fruiting branches and the number of inflorescence and infructescence were significantly increased by PAC treatment. Although PAC treatment significantly increased the total number of flowers and the number of female flowers of each inflorescence, no significant increase in the number of fruits of each infructescence was found, suggesting that some female flowers from PACtreated plants failed to mature fruits. PAC treatment at 0.8g·m-1 canopy diameter did not significantly affect seed size and oil contents, but increased seed yield of Jatropha by 2.4 times. In addition, PAC treatment led to more synchronous flowering and fruiting, which will facilitate harvesting of Jatropha fruits. These results suggest that gibberellin biosynthesis inhibitor PAC can effectively promote reproductive growth of Jatropha, which will help us to understand the physiological role of gibberellin and other plant hormones in regulation of Jatropha flower development, and are valuable for cloning of functional genes that will be used for the genetic improvement of Jatropha seed yield by transgenic approach.