白杨(ALB)是杨树中最具破坏性的木材枯燥昆虫之一。杨树\'沙林阳(PdS),一种新的杨树品种,对ALB侵染表现出较强的抗性。然而,PdS抗虫的分子机制尚不清楚。这里,我们发现ALB侵染后PdS韧皮部的木脂素含量远高于健康树木,在人工饮食中添加木脂素可显着降低:幼虫重量;消化酶活性(纤维素酶[CL],聚半乳糖醛酸酶[PG]);解毒酶活性(羧酸酯酶[CarE],谷胱甘肽S-转移酶[GSH-ST]);和防御酶活性(过氧化氢酶[CAT])。我们进一步鉴定了木酚素生物合成相关的PdPLR1基因(Pinoretinol-lariciresinol还原酶,PLR)基于转录组分析,在ALB攻击的PdS韧皮部中显著上调。PdPLR1在拟南芥中的过表达增加了木酚素的含量。相比之下,在PdS中沉默PdPLR1可显著降低PdPLR1的表达水平和木酚素含量,分别降低82.45%和56.85%。然而,沉默PdPLR1增加了成虫产卵和卵孵化的数量。CL的活动,PG,CarE,用沉默的PdPLR1饲喂PdS韧皮部的GSH-ST和CAT以及幼虫的生物量显着高于对照。一起来看,上调PdPLR1通过调节木酚素合成增强PdS对ALB的抗性。我们的发现为PdS-ALB相互作用的分子机制提供了深入的见解,为理解杨树对害虫感染的防御奠定了基础。
Anoplophora glabripennis (ALB) is one of the most devastating wood boring insects of poplars. Populus deltoides \'Shalinyang (PdS), a new poplar variety, shows strong resistance to ALB infestation. However, the molecular mechanism of insect resistance in PdS is unclear. Here, we found that
lignan content was much higher in PdS phloem after ALB infestation than in healthy trees, and that adding
lignan to artificial diet significantly reduced: larval weight; digestive enzyme activity (cellulase [CL], polygalacturonase [PG]); detoxification enzyme activity (carboxylesterase [CarE], glutathione S-transferase [GSH-ST]); and defense enzyme activity (Catalase [CAT]). We further identified the
lignan biosynthesis-related PdPLR1 gene (Pinoresinol-lariciresinol reductase, PLR) based on transcriptome analysis, and it was significantly up-regulated in the PdS phloem attacked by ALB. Overexpression of PdPLR1 in Arabidopsis increased th
lignan content. In contrast, silencing PdPLR1 in PdS significantly decreased expression levels of PdPLR1 and lignan content by 82.45% and 56.85%. However, silencing PdPLR1 increased the number of adults ovipositions and eggs hatching. The activity of CL, PG, CarE, GSH-ST and CAT and the biomass of larvae fed on phloem of PdS with silenced PdPLR1 were significantly higher than in the control. Taken together, up regulation of PdPLR1 enhanced PdS resistance to ALB by regulating
lignan synthesis. Our findings provide in-depth insights into the molecular mechanisms of PdS-ALB interactions, which lay the foundation for understanding of defense in poplars to pest infection.