Endophytic Bacillus, Enterobacter, and Klebsiella enhance the growth and yield of maize

Endophytic bacteria are those that colonise the internal tissues of plant without negative impact on plant health. This work aims to isolate the endophytic bacteria colonising Triticum vulgare and Phragmites australis and evaluate their compatibility as biostimulants to maize. Three of the six obtained isolates were selected upon their surpassing ability to stimulate the growth of maize seedlings (maximum of 18% increase in germination and 2.4-fold increase in the number of lateral roots). These isolates were molecularly identified as Klebsiella MK2R2, Bacillus B2L2 and Enterobacter E1S2. The response of maize seedlings to the combined effect of these isolates revealed that Bacillus B2L2, containing treatments, surpassed the other treatments in growth vigour parameters and upon this result these treatments were applied in a field experiment either alone or in combination with 100% N fertilisation. Maize plants, inoculated with Klebsiella MK2R2 and Bacillus B2L2 either alone or in combination with Enterobacter E1S2 in the presence of urea, surpassed significantly other treatments as the weight of ear increased almost two times and the number of grains increased 1.8 times compared to the control values. It could be concluded that the obtained strains are compatible biostimulants to maize.

Automated summary

Endophytic bacteria isolated from Triticum vulgare and Phragmites australis showed significant growth-stimulating effects on maize seedlings. Among the identified isolates, Klebsiella MK2R2, Bacillus B2L2, and Enterobacter E1S2 demonstrated compatibility as biostimulants for maize, enhancing maize growth and yield in field experiments with or without N fertilisation.