一种人工合成的茉莉酸类似物PDJ对寄主中黄瓜花叶病毒含量的影响

茉莉酸(Jasmonic acids, Ja)为一种新型的植物内源生长激素,广泛存在于自然界中,其主要生物学效应是对生长的抑制作用和对衰老脱落的促进作用,如抑制非休眠种子的萌发、强烈抑制根系的生长、促进块茎的形成等.Ja 作为关键的化学信号物质在植物损伤和病原菌侵染过程中具有重要作用.本实验以一种人工合成的茉莉酸类似物PDJ (9,10-二氢茉莉酸丙酯,9,10-Propyl dihydro-jasmonate)作为研究对象, 采用RNA点杂交方法对用不同浓度PDJ处理的假酸浆叶片中的黄瓜花叶病毒的基因组RNA负荷量进行测定, 结果表明:在处理后不同的时间段和不同的浓度条件下,PDJ对黄瓜花叶病毒的基因组RNA负荷量具有较大差别的影响.处理早期(7 d),与对照相比,各浓度PDJ促进CMV基因组RNA3的复制;随着时间的推移(处理21 d),0.001～5 mg/kg浓度PDJ处理的假酸浆叶片中CMV-RNA3负荷量的积累均明显低于对照,而高浓度50 mg/kg PDJ处理的高于对照,说明PDJ对CMV的促进作用随时间的增加逐渐消失;至处理42 d,对照中CMV RNA3的积累显著地大于各浓度的PDJ处理,显示出在处理后期PDJ对CMV较强的抑制作用,而且这种作用随PDJ浓度的降低而增强.

Influence of cucumber mosaic virus loading by a synthesized jasmonic acid analogue in plant

Jasmonic acidis(Ja)is an endogenous regulators with ubiquitous distribution in plants. There are a variety of jasmonic acid analogues (JAs) with important functions in regulation of plant organ formation and many other phtophsiological processes, such as inhibition of germination of non-dormancy seeds, intimidation of plant root growth, stimulation of tuber formation etc. As a key chemical signal, JA is commonly involved in plant response to mechanical damage and pathogen infection. PDJ(9,10-Propyl dihydro-jasmonate)is a kind of synthesized jasmonic acid, which has been used as a plant growth regulator. In this study, RNA spot hybridization was used to detect the replication of cucumber mosaic virus (CMV) on Nicandra physalodes plants, which were treated by different concentration of PDJ. Phosphor image laser scanner was used to quantify the result of viral RNA hybridization. Our result showed that the accumulation of CMV RNA3 in infected plant leaves was markedly influenced by PDJ treatment, and a time-and dose-dependent model was established. During the early stage of PDJ treatment (7d), the amount of CMV genomic RNA3 accumulated more rapidly than non-PDJ control. But PDJ treatment reduced the viral-RNA loading compared with the control as time proceeded. 21 days after treatment, the viral RNA3 loading in host leaves treated with 0. 001-5 mg/kg PDJ was significantly lower than those untreated leaves, but loading in those treated with 50 mg/kg PDJ was still higher than in untreated ones. After 42 d treatment, the viral RNA3 loading in host leaves of the control was higher than all leaves treated with PDJ. The inhibition was enhanced with decreasing concentration of PDJ.