Tomato plants (cv. Naomi) were grown until the 7th cluster in a greenhouse during the period Feb.–Jun. 1999 using a closed sub-irrigated soilless system. Plants were raised in pots (10 L) filled with peat and pumice (1:2 v:v) substrate. Thirty-one days after transplanting three nutrient solutions (NS) with electrical conductivity (ECs) of 2, 4, and 6 dS/m were applied to the plants. The EC of nutrient solutions were achieved by preparing NS from rain water (low EC) or from well water (high EC). Intermediate EC was obtained by mixing equal parts of the 2 and 6 dS/m NS. By increasing ECs the mean weight of fruit decreased, while dry matter, titratable acidity, soluble solids, and ascorbic acid contents of fruits increased. Also the color of fruits was positively influenced by the ECs. The index of colour (a*/b*)2, that is positively correlated with the lycopene content, increased by 73 % when increasing ECs from 2 to 4-6 dS/m.
La concentrazione delle asportazioni come criterio per il controllo della nutrizione minerale in ciclo chiuso: applicazione su pomodoro ‘Naomi’
SANTAMARIA, Pietro;SIGNORE, ANGELO
2004-01-01
Abstract
Tomato plants (cv. Naomi) were grown until the 7th cluster in a greenhouse during the period Feb.–Jun. 1999 using a closed sub-irrigated soilless system. Plants were raised in pots (10 L) filled with peat and pumice (1:2 v:v) substrate. Thirty-one days after transplanting three nutrient solutions (NS) with electrical conductivity (ECs) of 2, 4, and 6 dS/m were applied to the plants. The EC of nutrient solutions were achieved by preparing NS from rain water (low EC) or from well water (high EC). Intermediate EC was obtained by mixing equal parts of the 2 and 6 dS/m NS. By increasing ECs the mean weight of fruit decreased, while dry matter, titratable acidity, soluble solids, and ascorbic acid contents of fruits increased. Also the color of fruits was positively influenced by the ECs. The index of colour (a*/b*)2, that is positively correlated with the lycopene content, increased by 73 % when increasing ECs from 2 to 4-6 dS/m.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
