COMPARATIVE STUDY OF BIO- AND CHEMICAL FERTILIZATION IN STRAWBERRY PRODUCTION - Fertilizers: Components, Uses in Agriculture and Environmental Impacts - page 143

Figure 5. Interaction effect of the fertilizer type and cultivar (A x B) on TPC in strawberry fruits.
'Joly' was the richest in TPC (508.5 mg/100 g FW), whereas a 3-fold lower TPC was
found in cv 'Clery' (162.3 mg/100 g FW). Since no significant differences were observed in
the corresponding TAC values, this parameter is considered to be mostly uniform among the
tested cultivars.
Considering the interaction effect of the fertilizer type and cultivar, the highest and
similar TPC values were expressed by cv 'Joly' in both fertilizer treatments (Figure 5).
These values exceed 500 mg per kg of fresh strawberry fruit, being 2 to 3 times higher
than those of the cultivars with the lowest TPC (' Dely ' and ' Clery '). The ' Clery ' cultivar
exhibited an almost 2- fold higher TPC level in the biofertilizer treatment (205.7 mg/100 g
FW), whereas cv 'Dely' expressed similar values affected by both fertilizer types. Although
TPC greatly differed as a result of the interactions impact of fertilizer type and cultivar, no
significant differences were observed in the obtained results for TAC.
D ISCUSSION
Soil Microbial Counts
Changes in t h e number of particular systematic and physiological microorganisms
groups in soil as well as their activity can be used as important indicators of soil biological
productivity and the economic justifiability which is actually governed by t h e fertilizer
type (Hole et al., 2005; Stark et al., 2007; Cerny et al., 2010; Mandić et al., 2012; Pešaković
et al., 2013). The results in this chapter inferred that the applied biofertilizer, as an
alternative measure of supplementing soil with nitrogen assimilatives, increases total number
of microorganisms, the number of Azotobacters and oligonitrophils in the soil. Not only is
this effect an indicator of a pronounced nitrogen-fixing capacity of strains contained within