Cytokinin-Induced Parthenocarpic Fruit Development in Tomato Is Partly Dependent on Enhanced Gibberellin and Auxin Biosynthesis |
| |
| Authors: | Jiangang Ding Biwei Chen Xiaojian Xia Weihua Mao Kai Shi Yanhong Zhou Jingquan Yu |
| |
| Institution: | 1. Department of Horticulture, Zhejiang University, Hangzhou, People’s Republic of China.; 2. Key Laboratory of Horticultural Plants Growth, Development and Quality Improvement, Ministry of Agricultural, Hangzhou, People’s Republic of China.; 3. School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, People’s Republic of China.; Wake Forest University, United States of America, |
| |
| Abstract: | Fruit set of plants largely depends on the biosynthesis and crosstalk of phytohormones. To date the role of cytokinins (CKs) in the fruit development is less understood. Here, we showed that parthenocarpic fruit could be induced by 1-(2-chloro-4-pyridyl)-3-phenylurea (CPPU, an active CK) in tomato (
Solanum
lycopersicum
cv. Micro-Tom). The fresh weight of CPPU-induced parthenocarpic fruits was comparable with that induced by GA3. Importantly, CPPU-induced parthenocarpy was found to be compromised by simultaneous application of paclobutrazol (a GA biosynthesis inhibitor), and this effect could be restored by exogenous GA3. Like pollination, CPPU-induced fruit showed enhanced accumulation of GA1+3 and indole-3-acetic (IAA), which were accompanied by elevated expression of GA biosynthesis genes like SlGPS, SlGA20ox1, SlGA20ox2 and SlGA3ox1, and IAA biosynthesis gene ToFZY. Elevated GAs level in CPPU-induced fruits was also associated with down-regulation of GA inactivation genes, namely SlGA2ox1,2,3,4,5 in comparison with untreated control. These results suggested that CKs may induce parthenocarpy in tomato partially through modulation of GA and IAA metabolisms. |
| |
| Keywords: | |
|
|
