Integrated Application of Nitrogen, Molybdenum and Plant Growth-Promoting Rhizobacterium can Enhance the Sugarcane Growth

Adequate nitrogen (N) supply plays an important role in sugarcane production. Efficiency of N fertilization can be enhanced through fertilization with molybdenum (Mo) and inoculation with plant growth-promoting rhizobacteria (PGPR). This study assessed the development of sugarcane inoculated with PGPR and fertilized with Mo and N. The field experiment was carried out in randomized blocks and factorial arrangement (2 x 2 x 2), using two Mo doses and two N doses in plants without and with inoculation of PGPR Stenotrophomonas sp. (UAGC 869). We evaluated the varieties RB867515 and RB92579 at the beginning and end of the vegetative growth in the cane plant and ratoon cycles. There was no effect triple interaction. In both varieties and cycles, N stimulated production of shoot dry mass (SDM). Mo favored the initial development in both cycles of RB867515 but this effect was not observed in pre-harvesting. The UAGC 869 rhizobacteria increased the root dry mass above 70% in both cycles of RB867515. In the ratoon cycle, this gain results in SDM reduction of this variety. In RB92579, N and UAGC 869 interaction increased stalk growth, tillering, and SDM production in the plant cane cycle, surpassing N fertilization. Mo showed effect in the ratoon cycle only, when inoculation did not promote the growth of this variety. The beneficial interaction of inoculation with N or Mo on the development of sugarcane depends on the variety and the cycle evaluated.

Automated summary

Adequate nitrogen supply is crucial for sugarcane production, and its efficiency can be enhanced by fertilizing with Mo and inoculating with PGPR. This study found that the beneficial interaction of inoculation and fertilization depends on the sugarcane variety and growth cycle.