Yield and content of biogenic elements in tomato fruit at different NaCl concentrations in nutrient solution

Kakvoću svježih plodova rajčice, osobito sadržaj minerala moguće je poboljšati povećanjem EC-vrijednosti, odnosno koncentracije NaCl-a u hranivoj otopini bez značajnijeg smanjenja prinosa. Istraživanje je provedeno tijekom 2004. i 2005. godine na sorti Belle, u hidroponima na pločama kamene vune s ciljem utvrđivanja utjecaja povećane koncentracije NaCl-a u hranivoj otopini na prinos rajčice i sadržaj biogenih elemenata u plodu. Pokus je postavljen po metodi slučajnog bloknog rasporeda u četiri ponavljanja, a uzorkovanje je provedeno u tri roka berbe. Hraniva otopina EC-vrijednosti 2 dS/m korištena je kao kontrola, a povećane ECvrijednosti su postignute dodavanjem NaCl-a u standardnu hranivu otopinu, 0,05 % pri 3 dS/m, 0,125 % pri 4,5 dS/m i 0,2 % pri 6 dS/m. Najveći prinos zabilježen je pri fertirigaciji standardnom hranivom otopinom i varirao je od 2,06 do 2,60 kg/biljci u 2004. i od 3,41 do 5,19 kg/biljci u 2005. Koncentracije 0,05 i 0,125 % NaCl-a rezultirale su statistički jednakim prinosom i sadržajem biogenih elemenata, a koncentracija 0,2 % NaCl-a signifikantno manjim vrijednostima navedenih parametara. Povećanjem koncentracije NaCl-a ostvareno je značajno povećanje sadržaja suhe tvari koje je proporcionalno povećanju NaCl-a u hranivoj otopini.Quality of fresh tomato fruits, especially mineral content can be improved by increasing the EC value, or the concentration of NaCl in the nutrient solution without a significant reduction in yield. The study was conducted during the years of 2004 and 2005 with Belle tomato variety in hydroponics rock wool slabs in order to determine the impact of increased concentrations of NaCl in the nutrient solution on tomato yield and content of biogenic elements in the fruit compared to the standard solution without added NaCl and the EC-value of 2 dS/m. The experiment was set in a randomized complete block design with four replications and sampling was conducted in three harvests. The nutrient solution with EC-value of 2 dS/m was used as a control and increased EC-values were achieved by adding NaCl in the standard nutrient solution, 0.05% at 3 dS/m, 0.125% at 4.5 dS/m and 0.2% at 6 dS/m. The highest yield was recorded with a standard nutrient solution treatment and ranged from 2.06 to 2.60 kg/plant in 2004 and from 3.41 to 5.19 kg/plant in 2004. In comparison to the standard solution without added NaCl, the concentration of 0.05 and 0.125% NaCl resulted in statistically equivalent yield and content of biogenic elements, and the concentration of 0.2% NaCl with reasonably smaller values of these parameters. Increasing NaCl recorded a significant increase in dry matter content, which is proportional to the increase of NaCl in the nutrient solution