Hydroponic technologies

This open access book, written by world experts in aquaponics and related technologies, provides the authoritative and comprehensive overview of the key aquaculture and hydroponic and other integrated systems, socio-economic and environmental aspects. Aquaponic systems, which combine aquaculture and vegetable food production offer alternative technology solutions for a world that is increasingly under stress through population growth, urbanisation, water shortages, land and soil degradation, environmental pollution, world hunger and climate change.Hydroponics is a method to grow crops without soil, and as such, these systems are added to aquaculture components to create aquaponics systems. Thus, together with the recirculating aquaculture system (RAS), hydroponic production forms a key part of the aqua-agricultural system of aquaponics. Many different existing hydroponic technologies can be applied when designing aquaponics systems. This depends on the environmental and financial circumstances, the type of crop that is cultivated and the available space. This chapter provides an overview of different hydroponic types, including substrates, nutrients and nutrient solutions, and disinfection methods of the recirculating nutrient solutions

The influence of K:Ca:Mg:Na Ratio and total concentration on yield and fruit quality of soilless-grown tomatoes: A modelling approach

This study describes an application of Systematic Variation method (SV) for optimizing cation proportions (K, Ca, Mg, Na) and the total element concentration of hydroponically-grown tomatoes. A randomized complete-block design with 5 replications (3 plants per experimental unit) was used to compare a factorial combination of 4 proportions of K:Ca:Mg:Na and 2 total concentrations of elements (30 and 60 meq L-1). Each of the cation proportion treatment was defined by a high proportion of one cation (V=0.64) and an equally low proportion of the others (v=0.12) for a total amount of one (V + 3v = 1). The highest total and marketable yield were obtained in treatment with high proportion of K (avg. 2.94 and 2.72 kg plant-1, respectively) and Ca (avg. 2.84 and 2.65 kg plant-1, respectively), while treatments with high proportion of Mg (avg. 2.59 and 2.22 kg plant-1, respectively) and Na (avg. 2.21 and 2.09 kg plant-1, respectively) gave the lowest values. The highest incidence of blossomend rot was observed in treatments with high proportion of Mg and K (avg. 10.8 % and 3.7 % of total yield, respectively). Fruit quality (soluble solids, titratable acidity, EC) improved by increasing the proportion of K and Na and the total concentration. The SV method showed that for maximise the marketable yield it is necessary to include a large amount of K and Ca in the nutrient solution

Leaf area estimation model for small fruits from linear measurements. HortScience

Models were defined that accurately estimate the leaf area of small fruits (raspberry, gooseberry, blackberry, highbush blueberry and currants