بررسی مدیریت آبیاری و بسترهای متفاوت در کشت بدون خاک بر خصوصیات کمّی و کیفی گوجه‌فرنگی گلخانه‌ای

Nowadays in the world, soilless culture as a kind of technique is known to give vegetable crops higher yield and quality. This experiment was conducted at research greenhouse of Agriculture and Natural Research Center of Golestan province in spring 2005. The purpose of this research was to investigate the effects of irrigation frequency and substrates on yield and fruit quality of greenhouse tomato (CV. Hamra). Irrigation was carried out for 4, 8 and 12 times a day. The substrates were Perlite, Leca and Perlite + Leca (1:1, w/w). The experimental design was factorial in the form of randomized complete design with four replicates. The substrates used in the experiment had no effect on most factors. However, TA (0.43 mg/100 l) and fruit set (48%) were increased significantly by perlite and Leca substrates, respectively. The results indicated that higher and lower marketable yields were obtained from plants irrigated 12 (1830.5 g/plant) and four times (1156.7 g/plant) per day, respectively. Also increasing irrigation schedule decreased the Titratable acidity but didn't significantly affect the other factors. According to these results, Irrigation of 12 times per day and Leca substrate increased vitamin C and marketable yields, leading to optimum quality and quantity fruit set and the decreased TA (0.33 mg/100 l) in fruits in this treatment.