The use of biostimulants in plants is among the novel and integrated approaches in plant protection to increase crop tolerance to multiple biotic and abiotic stresses. In this context, seed coating with thyme essential oil and the endophytic bacterium Paraburkholderia phytofirmans was performed on durum wheat seeds in order to investigate their effects on germination of seeds and seedling growth. An in vitro assay was used to evaluate their effects on acidification, amylolytic activity in seeds, and on the peroxidases activity and phenolic content in wheat seedlings. To ascertain the endophytic behaviour of P. phytofirmans, Gfp (green fluorescent protein) marked mutant (PsJN*) was used for bacteria quantification in roots, stems and leaves using Real-Time PCR. Afterwards, a hydroponic culture system was used to study their effect on plant growth at an advanced stage. Seed coating with both agents resulted in the priming of seeds, illustrated by (i) earlier and higher acidification and amylolytic activity of seeds, (ii) induced changes in peroxidases activity and total phenolic content in wheat seedlings, (iii) an increased germination rate, and (iv) increased shoot and root development. The systemic spread of bacteria was confirmed within 7 days. The difference between the effects of P. phytofirmans and thyme oil on seed acidification, plant peroxidases activity, phenolic content, and shoot and root development suggests that they employ different mechanisms for seed priming and plant growth promotion in wheat plants.

在植物中使用生物刺激剂是植物保护中新的综合方法之一，可提高作物对多种生物和非生物胁迫的耐受性。在这种情况下，用百里香精油和内生细菌 Paraburkholderia phytofirmans 对硬粒小麦种子进行种子包衣，以研究它们对种子发芽和幼苗生长的影响。体外试验用于评估它们对酸化、种子淀粉分解活性以及小麦幼苗过氧化物酶活性和酚含量的影响。确定P. phytofirmans的内生行为(绿色荧光蛋白) 标记突变体 (PsJN*) 用于使用实时 PCR 对根、茎和叶中的细菌进行定量。之后，使用水培系统研究它们对晚期植物生长的影响。两种试剂的种子包衣导致种子引发，说明：(i) 种子的更早和更高的酸化和淀粉分解活性，(ii) 诱导小麦幼苗中过氧化物酶活性和总酚含量的变化，(iii) 发芽率增加，和 (iv) 增加枝条和根部的发育。细菌的全身传播在 7 天内得到证实。P. phytofirmans 和百里香油对种子酸化、植物过氧化物酶活性、酚类含量的影响之间的差异，