Effect of Azospirillum brasilense and chemical fertilization on the growth, development, yield and fruit quality of strawberry (Fragaria x ananassa Duch) [Efecto de Azospirillum brasilense y fertilización quemica sobre el crecimiento, desarrollo, rendimiento y calidad de fruto de fresa (Fragaria x ananassa Duch)]

Abstract

The effect of chemical fertilization and Azospirillum brasilense on strawberry growth, development, yield and fruit quality was evaluated. Three treatments were applied: T1: application of A. brasilense at a concentration of log 9 colony forming units (CFU) / plant; T2: A. brasilense at a concentration of log 9 CFU/plant + chemical fertilization; T3: chemical fertilization; and T4: control. The variables evaluated were: number of leaves (Nh), of flowers (Nfl) and fruits (Nfr), leaf area (AF), plant dry weight (PS), root length (LR) plant height (AL), yield per plant (RP) and fruit size (TF). Relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (RAF) and leaf weight ratio (RPF) were calculated from the dry weight. Results show that the concentration of A. brasilense used caused null effects or inhibited growth and yield; manifested in leaf area reduction, leaf thickness and plant fragility increase, from the higher values of AFE; it also led to less production of biomass, producing reduction of the fruit size and weight. The chemical fertilization in general terms had positive effects on the quality and yield of the fruit, resulting the best treatment in Nh, biomass production, Nfl, and AF variables at 35, 100, 145 and 35 dde, respectively. No significant differences were found in AP, LR, NFR, TCR, TAN, RAF and RPF in any stage of growth