Zhou Yan, Cai Hongyu, Zhao Renjie, Wang Chunyu, Zhang Jun, Yang Minsheng, Wang Jinmao
Forest Tree Genetics and Breeding Laboratory, College of Forestry, Hebei Agricultural University, Baoding 071001, China.
Faculty of Life Sciences, Northeast Agricultural University, Harbin 150030, China.
Plants (Basel). 2025 Aug 18;14(16):2563. doi: 10.3390/plants14162563.
With the increasing severity of forest pest problems, breeding insect-resistant varieties has become a crucial task for the sustainable development of forestry. The highly insect-resistant triploid Populus line Pb29, genetically modified with , served as the maternal parent in controlled hybridization with three paternal Populus cultivars. Hybrid progenies were obtained through embryo rescue and tissue culture. Results showed that 4 °C storage was favorable for pollen preservation, with 84K poplar exhibiting superior pollen viability and embryo germination rates. All progenies displayed significantly lower seedling height and ground diameter growth than the maternal parent ( < 0.05), with some showing leaf shape and branching variations. Among the three crosses, the 84K-sired progeny exhibited the best growth performance but the highest variability. PCR analysis confirmed stable inheritance of the and genes from Pb29, showing tight linkage. Progenies carrying exhibited detectable gene transcription and toxic protein accumulation, though expression levels varied due to copy number, insertion sites, and potential co-suppression effects. Ploidy analysis suggested all hybrids were aneuploid, with lower survival rates than the maternal parent. Insect-feeding assays confirmed high resistance in all -inheriting progenies, with an average larval mortality rate of 97.03%. Mortality rates and death indices significantly correlated with transcript abundance and toxin protein levels. These results demonstrate that insect resistance is stably inherited through hybridization. Transgene expression appears co-modulated by copy number, insertion sites, and ploidy status. Simultaneously, it was found that the aneuploid progeny derived from triploid hybridization exhibited growth disadvantages. This provides an important basis for subsequent poplar improvement breeding.
随着森林害虫问题日益严重，培育抗虫品种已成为林业可持续发展的关键任务。高度抗虫的三倍体毛白杨品系Pb29，通过基因改造，作为母本与三个父本毛白杨品种进行控制杂交。通过胚胎拯救和组织培养获得杂交后代。结果表明，4℃储存有利于花粉保存，84K杨表现出优异的花粉活力和胚萌发率。所有后代的苗高和地径生长均显著低于母本（<0.05），部分表现出叶片形状和分枝变异。在三个杂交组合中，84K父本的后代生长性能最佳，但变异性最高。PCR分析证实Pb29的和基因稳定遗传，显示紧密连锁。携带的后代表现出可检测的基因转录和毒蛋白积累，尽管表达水平因拷贝数、插入位点和潜在的共抑制效应而有所不同。倍性分析表明所有杂种均为非整倍体，存活率低于母本。昆虫取食试验证实所有继承的后代均具有高抗性，平均幼虫死亡率为97.03%。死亡率和死亡指数与转录丰度和毒素蛋白水平显著相关。这些结果表明，昆虫抗性通过杂交稳定遗传。转基因表达似乎受拷贝数、插入位点和倍性状态的共同调节。同时，发现三倍体杂交产生的非整倍体后代表现出生长劣势。这为后续杨树改良育种提供了重要依据。
