Effects of Streptomyces <i>Biofertilizer</i> to Soil Fertility and Rhizosphere’s Functional Biodiversity of Agricultural Plants

Abstract

In the present study, a biofertilizer on the basis of Streptomyces fumanus gn-2 was used for the treatment of wheat and soybean seeds (dose 10 4 spore/ml) before planting them in soil with low fertility in order to determine the effect of this biological agent on germination rate; the growth of seedlings, shoots, and the maturation phase of plants; the rhizosphere's functional biodiversity; and the resistance of these plants to pathogens. Seeds were soaked in the suspension for a period of two or three hours. During the growing season of the crop, no additional fertilizing and spraying of a biopesticide against diseases or pests occurred. Despite the soil having low fertility, low quantities of organic matter, and not having been before used for the cultivation of agricultural plants, this biofertilizer showed a strong stimulatory effect on the growth of seeds and seedlings of wheat and soybeans. The average germination and seed vigor increased by 1.5 -2.0 times, and the phenophases were accelerated to three to five days. In all phases of vegetation, the ammonifying bacteria in the presence of an antagonist (a biological agent) developed rapidly and were constantly present in significant numbers in the rhizosphere. Streptomyces fumanus introduced into nonsterile soil entered into competition with the local soil microflora and had the ability to colonize the rhizosphere system of plants. The use of a formulation of Streptomyces gn-2 has improved the composition of rhizosphere microflora, attracting saprophytic microorganisms: ammonificators and oligotrophs. The presence of the biocontrol microorganism Streptomyces fumanus in the rhizosphere plays an important role in enhancing the growth and development of useful groups, such as nitrogen-fixing bacteria. 556

Growth Promotion of <i>Telfairia occidentalis</i> by Application of <i>Chlorella vulgaris</i> (Bioinoculant) Colonized Seeds and Soil under Tropical Field Conditions

“…Likewise, relatively lower germination times were obtained for seeds amended with Chlorella vulgaris before sowing and in treatment pot where both the seed and soil were amended with Chlorella vulgaris. This observation suggests that Chlorella vulgaris enhanced the germination of Telfairia occidentalis seeds after sowing unlike NPK fertilizer and poultry manure which also agrees with the report of Doolototkeldieva et al [18] that Streptomyces fumanus used to treat wheat and soybeans before planting increased average germination of wheat and soybeans by 1.5…”

“…Most of these bio-fertilizers are present and predominant in the rhizosphere where they effectively enhance plant growth [17] [18]. Bio fertilizers could be bacteria, fungi, cyanobacteria or microalgae.…”

Biofertilizer Production for Agronomic Application and Evaluation of Its Symbiotic Effectiveness in Soybeans

“…Biofertilizer is usually produced using Rhizobium species. However, in this study, Bradyrhizobium and Streptomyces species were used to produce biofertilizer because the presence of the biocontrol microorganism Streptomyces in the rhizosphere plays an essential role in enhancing the growth and development of useful bacteria, such as nitrogen-fixing bacteria [39]. Plant growth promotion can be induced by the function of a single…”

Streptomyces: implications and interactions in plant growth promotion

“…RSF17, Streptomyces vinaceus CRF2, Streptomyces sp. CRF14, Streptomyces pulcher CRF17, Streptomyces griseoincarnatus SCF18 Javaid and Sultan ( 2013 ) Streptomyces PRIO41 Pepper Robles-Hernández et al ( 2015 ) Streptomyces mutabilis Wheat Toumatia et al ( 2016 ) Streptomyces fumanus gn-2 Soybean Doolotkeldieva et al ( 2015 ) …”