УДК 577 . 15 ISOLATION OF MICROBIAL GROUPS FROM A SEAWEED EXTRACT AND COMPARISON OF THEIR EFFECTS ON A GROWTH OF PEPPER CULTURE ( CAPSICUM ANNUUM L . )

Intensive application of chemical fertilizers in agriculture has caused damage to the ecological state of the agricultural systems [1]. The use of biofertilizers is an alternative to improve the conditions of Mexican fields and world-wide. Biological fertilizers do not contaminate the soil and atmosphere and help to produce healthy foods [2]. Seaweeds and their derivatives are used in agriculture as potential plant growth regulators. The main types of seaweeds are: Chlorophyta, Euglenophyta, Pyrrophyta, Chrysophyta and Rhodophyta. Biological regulators are substances that in small concentrations cause a physiological effect in plants inhibiting or stimulating specific function. Some of them are phytohormones (absicines, auxins, cytokines, gibberellins, ethylene) and microbial enhancers. Agricultural enhancers are defined as biological or nonbiological agents which reduce the time of growth, increase the production and/or quality of the agricultural products as well as the time of the flowering and fruition, the fruit size, etc. [3]. The participation of microorganisms as enhancers is related to their enzymatic activity. For example, potential for nitrogen fixing is a property of some prokaryotes [4]. It is known, that during the growth, the plant interacts intimately with microorganisms of soils. The interaction between the microorganisms and the plants can be beneficial, neutral or detrimental [5]. Three classes of microorganisms beneficial for the plants may be defined [5–11]: 1) as microorganisms that can increase the supplement of mineral nutrients essential for growth such as nitrogen and phosphorus; 2) microorganisms that stimulate the growth of the plants at an indirect form by means of the repression of pathogenic organisms (for example Bacillus thuringensis produces a toxin lethal for the phytopathogenic insects). These microorganisms are utilized for biocontrol, and are called such to differentiate it from the use of chemical insecticide. 3) Microorganisms that direct the biological growth of the plants, for example by phytohormones. The investigations of this form of growth promotion have begun recently and offer potential opportunities. A great number of bacteria such as Azotobacter sp, Pseudomonas sp. , Azosporillium sp. and some fungi such as the Fusarium sp. are able to produce a plant growth regulators such as gibberellins, auxins and cytokines. This study focuses on the microbial characterization of the seaweed extract (ALGAENZIMS®) and the role of microorganisms present in this bioproduct for its potential as fertilizer. ALGAENZIMS is produced by the company PalauBioquim (Mexico) as a biofertilizer. Its production is performed by seaweed treatment on alkaline solution and an addition of some other natural extracts from Mexican desert plants and salts. Previously it was demonstrated that this product applied at low concentrations (1–4 L/Ha) enhanced the growth and productivity of farming cultures [10]. However, the microbial components of ALGAENZIMS responsible for its agricultural effectiveness were not characterized. УДК 577.15