Abstract

Organic farming is an agricultural management that could favors the enhancement of soil organic matter and microbial biomass which actively contribute to the biochemical and biological processes responsible for soil fertility and nutrient availability for crops and sustainability. This sustainable management also represents a valid tool to increase biodiversity and functionality of soils. Moreover, the Phosphorous is a nutrient largely applied to soil through mineral fertilizers that, in according to soil properties. Phosphorous is an essential nutrient for plant growth, but is highly fixed in acid and basic soils conditions, becoming unavailable for crops. Phytases are a group of enzymes capable of releasing phosphate from phytate, one of the most abundant forms of organic phosphate in the natural environment. A study was carried out within a Italian national research project to assess the fertility of a soil under organic farming (La Morela Farm) in comparison with another under conventional management (CRA-ORT farm), both farms sited in the Sele River Plain (Campania Region, South Italy, cultivated with processing tomato (Solanum lycopersicum) corresponding to two cultivars: Docet (elongate for peeled tomatoes) and Faraday (orbed for tomato puree). During each year two samplings occurred in different crop cycles and years: 1) before the seedling transplanting (April 2011 and April 2012) and; 2) immediately after the tomato harvest (September 2011 and September 2012). Besides biochemical properties as dehydrogenase, β-glucosicosidase, invertase, phosphatase, urease and fluorescein diacetate hydrolases and biological properties as carbon biomass, soil microbial respiration, and soil microbiologic characterization and functional gene were assess. The bacterial community composition was evaluated in soils collected in post-harvest of the first year of study (2011) by Denaturing Gradient Gel Electrophoresis (PCR–DGGE). qPCR Real Time method specifically Phytase from Bacillus sp. was performed using the primer set MQH. Organic farming favored the enhance of soil fertility in term of organic carbon, soil microbial respiration and enzyme activities, also the organic management cause a great improvement of the relative abundance of Bacillus Phytase gen, but not present significant effects on total microbial population size and diversity.