Interactions between endophytic bacteria and their effects on poaceae growth performance in different inoculation and fertilization conditions

Abstract

Plant growth-promoting bacteria (PGPB) are a broad group of microorganisms that offer a huge, unexplored potential. We assessed the genetic diversity of endophytic bacteria that were isolated from corn and wheat plants in 3 different types of soils: A1 (Red Argisol), A2 (Red Latosol) and A3 (Red Nitossol). Endophytic bacteria were isolated from seedlings using 7 solid culture media and were further analyzed by 16S gene sequencing. IAA (Indole-3-acetic acid) production and PSI (Phosphorus solubilization index) bacteria capacity were tested in a randomly scheme in triplicate. In vitro association was assayed with 6 randomly selected endophytic strains. The experiment design was arranged in a randomly scheme with 10 replications. In vivo assays were performed to evaluate plant growth promotion using a low-fertility soil in different inoculation and/or fertilization conditions. The experiment design was arranged in a factorial 3x4 scheme in triplicate. The following characteristics were evaluated in both experiments in triplicate: plant biomass, total nitrogen content (TN) and endophytic population. As results, a total of 136 isolates were collected, and from these isolates, 41 strains were sequenced and classified into 4 major phylogenetic categories. There was a 38-fold variation between the highest (Ensifer adhaerens) and the lowest (Agrobacterium larrymoorei) IAA producer, and only 14% of strains were high phosphate solubilizers. In vitro assays identified both positively (Burkholderia ambifaria) and negatively (Pantoea ananatis) associative strains. In vivo assays showed that plant genotype can limit or induce the endophytic microbiota and that plant microbiota are highly influenced by soil fertility.

Inoculation of Merapi Indigenous Rhizobacteria as A Substitute Compost for Application in Rice Cultivation on Coastal Sandy Under Drought Stress

“…In addition, Merapi indigenous rhizobacteria can fertilize plants because they can produce IAA to become biological fertilizers for plant growth (Agung Astuti, 2014a). This result is also supported by the research results of Chaves et al, (2019), stating that of the 41 strains of rhizobacteria studied, 86% can produce IAA, and only 14% are high phosphorus solubilizing bacteria. This is in line with research results by Tuhuteru et al, (2019), mentioning that PGPR isolates BrSG.5 (Burkholderia seminali)s tested could produce IAA 41.41 mg kg-1, isolate BP25.2 (Bacillus methylotrophicus) was effective at producing N (0.05%), while isolate BP25.7 (Bacillus subtilis) was effective at producing residue P ( 0.22 ppm).…”

Efektivitas Bio-matriconditioning Benih Pratanam dengan Campuran Endo-rizobakteri dalam Meningkatkan Viabilitas dan Vigor Benih Cabai (Capsicum annuum L.)

“…Bakteri endofit mampu berperan dalam meningkatkan perkecambahan benih. Hal ini dikarenakan bakteri endofit mampu memproduksi hormon tumbuh berupa IAA yang dapat berperan dalam merangsang perkecambahan benih (Mukherjee et al, 2017;La Fua et al, 2019;Chaves et al, 2019;Sutariati et al, 2020a). Selain itu, bakteri endofit juga terbukti mampu melarutkan fosfat dan memfiksasi nitrogen (Zhu and She, 2018;Sutariati et al, 2020b).…”

“…Asam indol asetat (IAA) merupakan salah satu hormon pertumbuhan tanaman yang berperan penting dalam menstimulasi pertumbuhan tanaman. Hormon tumbuh yang dihasilkan bakteri endofit juga berperan dalam merangsang perkecambahan benih (Chaves et al, 2019;Sutariati et al, 2020a;Liu et al, 2021) 2017) yang melaporkan aplikasi konsorsium agens hayati mampu meningkatkan panjang akar, tinggi pupus dan juga berat berat kering tanaman. Lebih lanjut dilaporkan bahwa penggunaan biomatriconditioning benih arang sekam yang dintegrasikan dengan PGPR dapat meningkatkan pertumbuhan dan hasil tanaman padi gogo (Fitriani et al, 2021).…”

Genome sequencing and analysis of plant growth-promoting attributes from Leclercia adecarboxylata

“…At first, L. adecarboxylata strain Palotina was isolated in LB medium, growing well in DYGS (Dobereiner et al, 1995), following the isolation protocol by (Chaves et al, 2019). Visual assays determined bacteria morphology and colony color.…”