Wang Ziyi, He Chenxing, Zhang Yunmei, Luo Shuiwen, Wei Jianrong, Liu Jianfeng
College of Life Science, Hebei University, Baoding, China.
College of Life Science, Hebei University, Baoding, China; Engineering Research Center of Ecological Safety and Conservation in Beijing-Tianjin-Hebei (Xiong'an New Area) of MOE, China.
J Plant Physiol. 2025 Aug;311:154528. doi: 10.1016/j.jplph.2025.154528. Epub 2025 May 22.
Populus deltoids 'Shalinyang' (PdS) is a new poplar variety with insect resistance cultivated in the western region of China. Anoplophora glabripennis (ALB) is an important forestry pest that causes great harm to poplar trees. However, the research on the insect resistance mechanism of PdS is still unclear, so exploring its defense response mechanism against ALB can provide theoretical and technical support for the subsequent cultivation of new varieties of poplar suitable for extensive planting and resistant to biotic stress. This study primarily aims to elucidate the molecular mechanisms underlying PdS's inducible resistance by jasmonic acid (JA). Here, 50 μM JA was applied to 1-year-old PdS plants to verify its anti-insect effect in PdS. It was found that superoxide dismutase (SOD) activity and hydrogen peroxide (HO) content increased, malondialdehyde (MDA) content decreased, and the feeding area of ALB leaves and the number of stem bite marks decreased by 56.92 % and 49.33 % respectively compared to the control group. The results indicated that JA treatment had a positive regulatory effect on insect resistance in PdS. Based on the transcriptome data, the key gene PdSABP2A was screened from the methylesterase (MES) gene family that played an important role in plant defense response. The expression level of PdSABP2A gene also significantly increased in the external JA treatment experiment. The virus-induced gene silencing (VIGS) experiment was used for gene function validation, and it was found that the expression level of PdSABP2A gene decreased by 73.72 %, and the JA content also significantly decreased. In addition, PdS subjected to the VIGS silencing treatment were more severely nibbled by ALB. The larvae inside PdS plants grew faster, had higher activity of digestive and defense enzymes, and lower mortality rates, all of which indicated a decrease in PdS insect resistance. These findings indicated that the PdSABP2A gene is involved in regulating the synthesis of JA and inducing the defense response of PdS against ALB.
‘沙林杨’（Populus deltoids 'Shalinyang'，PdS）是中国西部地区培育的一种具有抗虫性的杨树新品种。光肩星天牛（Anoplophora glabripennis，ALB）是一种对杨树造成严重危害的重要林业害虫。然而，关于PdS抗虫机制的研究仍不明确，因此探索其对ALB的防御反应机制可为后续培育适合大面积种植且抗生物胁迫的杨树新品种提供理论和技术支持。本研究主要旨在阐明茉莉酸（JA）诱导PdS产生抗性的分子机制。在此，将50 μM JA施用于1年生的PdS植株，以验证其在PdS中的抗虫效果。结果发现，与对照组相比，超氧化物歧化酶（SOD）活性和过氧化氢（HO）含量增加，丙二醛（MDA）含量降低，ALB取食的叶片面积和茎干咬痕数量分别减少了56.92%和49.33%。结果表明，JA处理对PdS的抗虫性具有正向调节作用。基于转录组数据，从在植物防御反应中起重要作用的甲酯酶（MES）基因家族中筛选出关键基因PdSABP2A。在外部JA处理实验中，PdSABP2A基因的表达水平也显著增加。采用病毒诱导基因沉默（VIGS）实验进行基因功能验证，发现PdSABP2A基因的表达水平下降了73.72%，JA含量也显著降低。此外，经过VIGS沉默处理的PdS受到ALB的啃食更为严重。PdS植株内的幼虫生长更快，消化酶和防御酶活性更高，死亡率更低，所有这些都表明PdS的抗虫性降低。这些发现表明，PdSABP2A基因参与调节JA的合成并诱导PdS对ALB的防御反应。
