BACTERIAL-MULTISPECIES BIOINPUT: GROWTH-PROMOTION EFFECT IN PLANTS OF LETUCCE VAR. SAGESS

BERNABEU, PAMELA; BALATTI, PEDRO; VIO, SANTIAGO; GARCÍA, SABRINA; GALAR, MARIA LINA; GARBI, MARIANA; LODEIRO, ANÍBAL; LUNA, MARIA FLAVIA

Valparaíso

Congreso; ISME Latino América; 2019

Bioinputs based on Plant Growth Promoting Bacteria (PGPB) have emerged as a sustainable agricultural alternative. However, its adoption is still incipient in the Argentine horticultural area. We assessed the effect of a multispecies inoculant (Mz) on lettuce var. Sagess in seedling and productive stage in two experimental fields: (I) EE-J.H. and (II) EE-Gorina, La Plata (Argentina). Mz was formulated with 4 PGPB: Azospirillum brasilense Az39 (Az), Bacillus subtilis Dm-B10 (Ba) Gluconacetobacter diazotrophicus PAL-5 (Gl) and Pseudomonas fluorescens (Ps) (108-109 CFU ml-1), using equal volumes of each one. Mz was applied at sowing (S), transplant (T) and both times (ST), and each bacterium was applied individually at ST, adding 1 ml per 10 ml of substrate. The presence of the inoculated bacteria was determined at 20 days post inoculation in seedlings with Mz, detecting 104, 105 and 106 CFU g-1 of root for Ba, Gl, Ps, respectively. Az could not be identified by the used methodology. The aerial and root dry weight of inoculated seedlings significantly increased compared to the non-inoculated ones: 45%, 32% and 28% on average for Mz, Ba and Gl, respectively. The commercial fresh weight of inoculated plant was 38.5% significantly higher in Mz (Mz-S in I and Mz-S and Mz-SyT in II) compared to the non-inoculated ones. Gl was the only individually inoculated bacteria that significantly increased in 27% the commercial fresh weight per plant compared to the non-inoculated treatment.In the evaluated parameters, the multispecies inoculant achieved a greater effect regarding to the individually inoculated microorganisms.