关键词: 杨树, 食叶害虫, 蛀干害虫, 生物安全评价, 生物育种

Abstract:

Populus spp., as an economic forest, ecological protection forest and national reserve forest construction species, plays a pivotal role as a significant carbon sink in achieving the goal of “carbon peaking and carbon neutrality” due to their fast-growing and wide-adaptable characteristics. However, the productivity of poplar plantations has been seriously affected by foliage-feeding and wood-boring insect pests. Therefore, it is an urgent task to elucidate the molecular mechanism of insect resistance in poplar and cultivate new insect-resistant and high-yielding poplar varieties for the development of poplar plantations. In this paper, we firstly outline the progress of molecular mechanism of poplars in reducing biotic stress through forming leaf trichomes, fortifying physical defenses including increased wood density, and rapid responses of secondary metabolites such as intrinsic phenolic glycosides and volatiles, as well as protease inhibitors. Then, we summarize the main applications of poplar cross-breeding, transgenic breeding technology, and multi-omics analysis in the cultivation of new varieties of poplars with insect-resistance and in the mining of key resistant sites and genes. The biosafety evaluation methods and progress of insect-resistant transgenic poplars are analyzed. Finally, it is proposed that in the future, emphasis should be placed on analyzing the molecular mechanism of poplar resistance to trunk borers, and integrating traditional cross-breeding approach with modern breeding techniques such as transgenics, gene editing and whole genome selection around the breeding goals to realize polymer breeding for insect resistance, enhanced quality, and increased yield. Concurrently, it is essential to establish and improve the biosafety assessment protocols and regulations for transgenic and gene-edited poplars for laying a solid theoretical and practical foundation for the genetic improvement and molecular design breeding of insect-resistant poplars.

Key words: poplar, foliage-feeding pests, trunk borers, biosafety assessment, biotechnology breeding