Microbial Consortium Promotes Growth of Zinnia and Balsam Seedlings Raised in pro trays

Abstract

Zinnia and Balsam are flowering plants with high economic importance in floriculture. Inoculation of the planting medium with a beneficial microbial consortium is an innovative approach to produce quality and healthy seedlings in floriculture. In the present study the influence of a microbial consortium of the arbuscular mycorrhizal fungus (AMF) Funneliformis mosseae and a plant growth promoting rhizobacterium (PGPR) Bacillus sonorensis on flowering plants Zinnia and Balsam in pro-trays under poly house conditions was investigated. Estimation of various plant growth parameters such as plant height, stem diameter, bio-volume index, vigour index, plant strength, fresh weight, dry weight and nutrient uptake was carried out to analyse the ability of the consortium to improve seedling growth. Microbial parameters such as mycorrhizal root colonization and spore count, and population of PGPR in substrate was also studied. The results suggested that inoculating the substrate in pro trays before sowing the seeds with the consortium increased plant growth significantly compared to the uninoculated plants.

Influence of Microbial Consortium in the Production of China Aster and Gaillardia Seedlings

“…The total plant dry weight in inoculated seedlings was 140% higher in China aster and 172% higher in gaillardia compared to uninoculated seedlings (Table 1). This is in conformity with the results obtained for tomato, pepper, zinnia and balsam (Behera et al 2019;Desai et al 2020, Sukeerthi et al 2020.…”

“…Regarding stem diameter, inoculated plants showed significant increase by 58% in China aster and 68% in gaillardia seedlings, compared to uninoculated control, supporting our earlier study on flowering plants (Sukeerthi et al 2020). The BI of the plants, which indicates the quality of seedlings, showed 270% increase in China aster and 167% increase in gaillardia compared to uninoculated seedlings (Table 1).…”

“…The mycorrhizal spore numbers were 41 and 45 in the inoculated substrate of China aster and gaillardia, respectively, while uninoculated substrate did not harbor any spores (data not given). The significantly higher percent mycorrhizal root colonization and spore number in the substrate of seedlings inoculated with microbial consortium, as compared to uninoculated control, indicates the better proliferating ability of F. mosseae with China aster and gaillardia as also in other flowering plantszinnia and balsam (Sukeerthi et al 2020). Enhanced root colonization and spore number in the root zone because of inoculation with AMF + PGPR have been reported earlier in different crops (Anuroopa et al 2017;Pan et al 2020).…”

“…The CFU of B. sonorensis in the root zone substrate was found to be 4 × 10 4 •g -1 substrate in China aster and 3 × 10 4 •g -1 substrate in gaillardia, while these bacteria were not detected in the substrate of uninoculated treatment (data not given). The presence of inoculated PGPR in the root zone at the end of seedling stage was reported earlier in other crops (Desai et al 2020, Sukeerthi et al 2020. Synergistic interaction between F. mosseae and B. sonorensis promoting higher plant growth compared to single inoculation with either of them has been reported earlier in chilly (Thilagar et al 2014).…”

“…The number of infective propagules in the inoculum was estimated through the most probable number (MPN) method with 10-fold dilution (Porter 1979). The PGPR B. sonorensis and AMF F. mosseae was selected based on the positive results reported in earlier studies on other vegetable and flower plants (Thilagar et al 2014;Sukeerthi et al 2020).…”