College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China.
College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China.
Microbiol Res. 2024 Jun;283:127690. doi: 10.1016/j.micres.2024.127690. Epub 2024 Mar 9.
Rootstock is commonly used to enhance plant resistance to drought stress. However, it is necessary to investigate the effects of different rootstock, interstock, and scion combinations on rhizosphere and root endophytic bacteria under drought stress. We conducted a pot experiment to investigate how interstock [SH40, Jizhen 1 (J1), and Jizhen 2 (J2)] affects the drought tolerance and nitrogen (N) uptake and utilization of apple trees under drought stress. The results showed that the total dry weight, total chlorophyll content, carotenoid content, photosynthesis rate, and N absorption and utilization efficiency of apple trees decreased significantly, whereas relative electrolyte leakage increased significantly under drought stress. Membership function analysis showed that the apple plants with the J1 interstock had the greatest drought resistance. In addition, drought treatment significantly affected the diversity and composition of rhizosphere and root endophytic communities in all three rootstock/interstock/scion combinations. Further analysis revealed that the relative abundance of the plant pathogen Ralstonia was significantly increased in J2 drought-treated roots, compared to the other groups, whereas those of some potentially beneficial bacteria (0134_terrestrial_group, Phenylobacterium, Ellin6067, Kribbella, Chloronema, and Streptomyces) increased significantly in the J1 drought-treated sample. Co-occurrence network analysis showed that some potentially beneficial bacteria (Ellin6067, S0134_terrestrial_group, Pedomicrobium, and Subgroup_10) were significantly positively correlated with N content. These modifications of the rhizosphere and endophytic bacterial communities may influence the drought resilience and N uptake efficiency of different combinations of interstocks and scions. This study is a much-needed step towards understanding the stress response mechanism of scion-rootstock combinations.
砧木通常用于增强植物对干旱胁迫的抗性。然而，有必要研究不同砧木、中间砧和接穗组合在干旱胁迫下对根际和根内生细菌的影响。我们进行了盆栽实验，研究了中间砧 [SH40、Jizhen 1 (J1) 和 Jizhen 2 (J2)] 如何影响苹果在干旱胁迫下的耐旱性和氮 (N) 吸收和利用。结果表明，苹果总干重、总叶绿素含量、类胡萝卜素含量、光合速率和 N 吸收利用效率均显著下降，而相对电解质渗漏率则显著增加。隶属函数分析表明，J1 中间砧的苹果植株抗旱性最强。此外，干旱处理显著影响了三种砧木/中间砧/接穗组合的根际和根内生群落的多样性和组成。进一步分析表明，与其他组相比，J2 干旱处理的根中植物病原菌 Ralstonia 的相对丰度显著增加，而 J1 干旱处理的样本中一些潜在有益细菌（0134_terrestrial_group、Phenylobacterium、Ellin6067、Kribbella、Chloronema 和 Streptomyces）的相对丰度显著增加。共现网络分析表明，一些潜在有益细菌（Ellin6067、S0134_terrestrial_group、Pedomicrobium 和 Subgroup_10）与 N 含量呈显著正相关。这些根际和内生细菌群落的变化可能会影响不同砧木和接穗组合的耐旱性和 N 吸收效率。本研究是深入了解接穗-砧木组合胁迫响应机制的重要一步。
