Abstract
The increasing demand for water resources in the world has forced farmers to use low quality water for irrigation, such as saline water. Effects of water quality and irrigation management on growth and yield of tomato were investigated during the growing seasons of 2006/2007 under greenhouse conditions. Two water qualities (Fresh and saline water with EC 1.2 and 4.7 dS m(-1), respectively) were applied to a Red Gold tomato cultivar. Different irrigation managements were carried out at two irrigation frequencies (sub-surface drip irrigation for three and six days week(-1)) and three irrigation rates (2, 4 and 6 l h(-1)). The results revealed that saline irrigation water having an EC of 4.7 dS m(-1) significantly reduced all studied traits such as average fruit weight and total yield which reduced by 62.3 and 24.3% respectively, compared to irrigation with fresh water having an EC 0.5 dS m(-1). Irrigating tomato using sub-surface drip irrigation for six days week(-1) significantly stimulated number of leaves, enhanced fruit size and increased total yield 26.4% (from 98 to 133 ton hectare(-1)) compared to irrigation for three days week(-1). No significant differences were found in total yield when irrigated with 4 and 6 l h(-1). The interaction between water quality and irrigation management treatments exerted significant effects for most of the studied traits and revealed that irrigation with fresh water using subsurface drip irrigation for six days week(-1) and 4 l h(-1) gave the best results. However, total yield was less affected by saline water when plants were irrigated using subsurface drip irrigation for six days week(-1) with a rate of 6 l h(-1), and it is recommended for greenhouse tomato production to reduce the high cost of water desalinization.