ABSTRACT

The application of new agricultural technologies to attain sustainable production systems is necessary. The use of plant growth-promoting bacteria to improve plant growth and health has been studied for decades. This work aimed to isolate diazotrophic endophytic bacteria associated with sweet sorghum plants and study the interaction of their inoculation in combination with chemical N-fertilization on different sorghum cultivars. A bacterial collection of 181 isolates was constructed and characterized in vitro and in vivo. From that, the strains Enterobacter sp. UYSB89 and Kosakonia sp. UYSB139 were nifH⁺, produce IAA, defined as true endophytes and able to promote growth of two sweet sorghum under greenhouse conditions. The evaluated cultivars responded differentially to bacterial inoculation, the nitrogen fertilization doses and their interaction. Thus, plant growth is a multifactorial consequence of the interrelation between crop practices and the plant genotypes. This knowledge is a valuable factor in terms of understanding plant–bacteria endophyte interactions to preserve environmental sustainability during the implementation of agronomic practices.

中文翻译：

---

内生细菌，甜高粱（Sorghum bicolor）品种与化学氮肥之间的相互作用

摘要

必须应用新的农业技术来实现可持续的生产系统。数十年来，一直在研究使用促进植物生长的细菌来改善植物的生长和健康。这项工作旨在分离与甜高粱植物有关的重氮营养内生细菌，并研究其接种与化学氮肥结合对不同高粱品种的相互作用。的181个分离株甲细菌集合构建并表征的体外和体内。由此可见，肠杆菌属菌株。UYSB89和Kosakonia sp。UYSB139是nifH ⁺产生IAA，IAA被定义为真正的内生菌，能够在温室条件下促进两种甜高粱的生长。被评估的品种对细菌接种，氮肥剂量及其相互作用的反应不同。因此，植物生长是作物实践与植物基因型之间相互关系的多因素结果。就了解植物与细菌的内生菌之间的相互作用以在农艺实践的实施过程中保持环境的可持续性而言，这一知识是宝贵的因素。