An aquaponics experiment was conducted to test the efficacy of different substrate such as gravel mixed with saw dust (1:1, T1), only brick lets and gravels (T2 and T3) for 116 days from 1 March to 25 June, 2013 at the roof of a building at Bangladesh Agricultural University (BAU) residential area with two replications to produce tomato in summer. Tilapia (mean initial length and weight were 6.18±0.92 cm and 5.85±2.30 g, respectively) used as test animal at the rate of 134 fish/m3 water. The twenty days old healthy tomato seedlings were transplanted to the grow bed after stocking of tilapia. The waste water from the fish tank was irrigated using a 12 watt submersible pump to the vegetable beds and tank water was aerated with a 10 watt air pump fitted with two air stones. The irrigated water passed through the substrate where denitrifying and nitrifying bacteria converted nitrogenous compound to nitrites and then nitrates which then used by tomato plants as fertilizer and filtered water returned to the fish tank. Water quality, plant and fish growth were monitored fortnightly and detailed test was carried out three times in the lab. Evaporated and used up water was replaced with tap water daily. Data analysis showed that the water quality parameters were within the suitable range of fish culture. The mean length and weight of fish increased by 10.42±1.11 cm and 86.26±17.40 g, respectively. The FCR for tilapia feed used in the present aquaponic system was 2.73. Daily growth rate was 0.74% and the survival rate was 90%. Total fish production was found 130 tons/ha/116 days. In case of tomato, the results showed that overall plants growth and weight of fruits was higher in T3 than T1 and T2. Tomato production was 22.25, 37.74 and 87.41 tons/ha/116 days in T1, T2 and T3, respectively. Thus, present results revealed that the gravels substrate gave the highest tomato production than the brick lets and gravels mixed with saw dust substrate.Progress. Agric. 2014. 25: 54-62

Coeliac disease is an antibody-mediated enteropathy that presents permanent intolerance to ingested gluten, for which only treatment is lifelong devotion to a gluten-free diet. The aim of this study was to produce and investigate cracker biscuits prepared from gluten-free composite flour. Gluten was separated from wheat flour to make gluten-free wheat flour (GFWF). Raw rice, Bengal gram, fresh potatoes and Italian millet were dried and ground into powder. The cracker biscuits were prepared by incorporating different levels of gluten-free composite flour. The cracker biscuits were investigated for their physico-chemical and sensory properties. The spread ratio of control biscuits containing only 100% wheat flour was higher but weight was lower than other cracker biscuits containing gluten-free composite flour. Chemical analysis showed that gluten-free cracker biscuits had higher moisture, ash, and fat content, while lower protein content than control biscuits. The sensory results showed that overall acceptability, taste, flavor and texture scores differed significantly (p<0.05). The cracker biscuits containing 45% gluten-free wheat flour, 25% rice flour, 15% Bengal gram flour, 10% potato flour and 5% Italian millet flour was the favorite sample of the sensory evaluation with the highest overall acceptability among all types of gluten-free cracker biscuits.