Feng Yuan-Jiao, Wang Jian-Wu, Luo Shi-Ming
Institute of Tropical and Subtropical Ecology, South China Agricultural University, Guangzhou, China.
Ying Yong Sheng Tai Xue Bao. 2009 Aug;20(8):1883-90.
Biochemical and gene expression analysis methods were adopted to investigate the defensive substances and the defense-related genes expression in the roots and leaves of maize (Zea mays L. ) cultivar Gaoyou 115 after underground treatment with 10, 50, 100 and 200 micromol x L(-1) of jasmonic acid (JA) for 3-48 h, aimed to explore the timing- and concentration effect of belowground treatment with JA on the chemical defense response of maize. The chemical defense response of both treated roots and non-treated leaves of Gaoyou 115 was related to the time span of JA treatment and the concentration of JA. After treated with JA for 3-12 h, the gene expression of Bx9, PAL, PR-2a, MPI and FPS in treated roots was directly induced, resulting in an increase of DIMBOA content and a decrease of total phenol content, with the strongest induction effect detected at 100 micromol x L(-1) of JA, followed by at 50 micromol x L(-1), and at 10 micromol x L(-1). The induction effect weakened with time. Underground treatment with JA indirectly affected the chemical defense response of non-treated leaves. After underground treatment with 50 micromol x L(-1) of JA for 3 h, the gene expression of Bx9 and FPS in non-treated leaves was induced, which caused a consequent increase of leaf DIMBOA content. Within 6-24 h of JA treatment, the gene expression of Bx9, PAL, PR-1, MPI and TPS in leaves was enhanced, while the leaf DIMBOA and total phenol contents were declined. For most of the parameters measured, the direct induction effect on roots was much more significant and started earlier than the indirect induction effect on leaves, and an increasing trend was observed in the induction effect with increasing JA concentration.
采用生化和基因表达分析方法，研究了用10、50、100和200微摩尔×升⁻¹茉莉酸（JA）对玉米（Zea mays L.）品种高邮115进行地下处理3至48小时后，其根和叶中的防御物质及防御相关基因的表达，旨在探究地下施用JA对玉米化学防御反应的时间和浓度效应。高邮115经处理的根和未处理的叶的化学防御反应均与JA处理的时间跨度和JA浓度有关。用JA处理3至12小时后，处理根中Bx9、PAL、PR - 2a、MPI和FPS的基因表达被直接诱导，导致2,4 - 二羟基 - 7 - 甲氧基 - 1,4 - 苯并恶嗪 - 3 - 酮（DIMBOA）含量增加，总酚含量降低，在100微摩尔×升⁻¹ JA处理时诱导效果最强，其次是50微摩尔×升⁻¹，10微摩尔×升⁻¹时最弱。诱导效应随时间减弱。地下施用JA间接影响未处理叶的化学防御反应。用50微摩尔×升⁻¹ JA地下处理3小时后，未处理叶中Bx9和FPS的基因表达被诱导，进而导致叶片DIMBOA含量增加。在JA处理6至24小时内，叶片中Bx9、PAL、PR - 1、MPI和TPS的基因表达增强，而叶片DIMBOA和总酚含量下降。对于大多数测定参数，对根的直接诱导效应比叶的间接诱导效应更显著且开始时间更早，并且随着JA浓度增加诱导效应呈上升趋势。
