DIFFERENT SOILLESS CULTURE SYSTEMS AND THEIR MANAGEMENT

Soilless culture is growing plants without use of soil as a rooting medium, and divided into water culture and substrate culture. Among the water culture techniques, float hydroponics is adopted for the cultivation of fresh-cut leafy vegetables and aromatic plants. Substrate culture by using plastic bags has been applied successfully at commercial level for fruiting vegetables. Production scale, crops, growing cycles and length of each cycle, cost and management skills should be considered as well as environmental concerns in the decision of soilless culture system. Therefore, closed loop systems have gained importance for increasing sustainability in soilless cultivation. This presentation aims to summarize different soilless culture systems and the potential of their use in vegetable production

Effects of nutrition and "Bacillus amyloliquefaciens" on tomato ("Solanum lycopersicum L.") growing in perlite

Las rhizobacterias promotoras del crecimiento de las plantas (PGPR) son bacterias que viven libres y, como su nombre indica, promueven el crecimiento de las plantas. Sin embargo, también pueden ser de ayuda en el control biológico de las enfermedades de las plantas. En este estudio se investigaron los efectos de dos cepas comerciales de Bacillus amyloliquefaciens (FZB24 y FZB42) sobre la producción de tomate en sistemas abiertos y cerrados, en presencia de diferentes cantidades de nutrientes. Los tratamientos fueron: (1) tipo de sistema de nutrición (abierto o cerrado), (2) concentración de nutrientes (solución nutritiva completa o incompleta), (3) la PGPR aplicada (B. amyloliquefaciens FZB24, B. amyloliquefaciens FZB42, o un control sin PGPR). Se utilizó perlita como medio de crecimiento. Se evaluaron las variables relacionadas con la eficiencia del uso del agua, producción de tomate y calidad del fruto. La solución de nutrientes menos concentrada fue suficiente para un pleno crecimiento en el sistema abierto en ambas estaciones (primavera y otoño). Sin embargo, la misma solución de nutrientes disminuyó en otoño la producción en el sistema cerrado. La aplicación de ambas cepas de B. amyloliquefaciens aumentó la producción de las plantas de tomate un 8-9% en el sistema abierto en primavera, mientras que tuvo un efecto adverso sobre la producción en otoño en el sistema cerrado con la solución menos concentrada.Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria that, as their name suggests, promote plant growth. However, they can also be of help in the biological control of plant diseases. This study reports the effects of two different commercially available strains of Bacillus amyloliquefaciens (FZB24 and FZB42) on tomato production in open and closed systems in the presence of different amounts of nutrients. Three factors were tested: (1) the type of nutrition system (open or closed), (2) the concentration of the nutrient solution (full or half strength), and (3) the PGPR applied (either B. amyloliquefaciens FZB24 or B. amyloliquefaciens FZB42, or a no-PGPR control). Perlite was used as the growth medium. Variables related to water use efficiency, yield and fruit quality were assessed. The use of half strength nutrient solution was sufficient for full growth in the open system in both spring and autumn seasons. However, the same strength nutrient solution was associated with reduced yields in the closed system during the autumn season. The application of either strain of B. amyloliquefaciens increased the yield of the tomato plants by 8-9% in the open system in the spring, whereas they had an adverse effect on yield in the closed system under half strength nutrient solution conditions during the autumn

Effect of different irrigation schedules, substrates and substrate volumes on fruit quality and yield of greenhouse

This study was conducted to determine the effects of three irrigation schedules in combination with locally available substrates and different bag volumes on yield, fruit quality and water consumption of tomato (cv. Fantastic). The substrates were: (1) perlite, (2) pumice, (3) volcanic ash, (4) perlite + peat (4:1, v/v), (5) pumice + peat (4:1, v/v) and (6) volcanic ash + peat (4:1, v/v). Irrigation was carried out according to the drainage volume as (1) once, (2) twice and (3) four times a day. The experimental design was split split plots with 3 replicates. The main plots, subplots and sub-subplots were irrigation schedule, substrate volume (4 and 8 litres) and substrate, respectively. Cumulative yield at two week intervals and some quality parameters (average fruit weight, total soluble solids, total dry matter content, pH, EC, vitamin C, titratable acidity) were determined. Experimental factors were found to significantly affect on yield after the 10th week. The higher total yields were obtained from plants grown in perlite+peat (7.4 kg/plant) and perlite (7.2 kg/plant). 8 litres rooting volume per plant resulted in a higher total yield (7.4 kg/plant) in comparison with 4 litres (6.2 kg/plant). Total yield obtained from the plants irrigated once a day (6.4 kg/plant) was lower than those obtained from the plants irrigated twice (6.9 kg/plant) and four times (7.1 kg/plant) daily. Fruit quality parameters varied according to treatments and sampling dates

Automated irrigation management of organic greenhouse tomatoes

This research investigated the effects of different irrigation schedules and mulching in greenhouse organic tomatoes grown using an automated irrigation system based on root zone soil moisture sensors. Two consecutive short cycle crop productions were conducted in a polyethylene greenhouse at Ege University, Bornova-Izmir, Turkey. Full irrigation (no stress) in which soil water content was allowed to be depleted to 20% in the plant root zone and two deficit irrigation treatments in which soil water content was allowed to be depleted to 35% (Deficit 1) and 50% (Deficit 2) of the available water content in the plant root zone were tested using sensor technologies and compared with and without mulching. An irrigation controller was installed in each irrigation treatment and the soil moisture was controlled and monitored with a theta-probe sensor installed at 15 and 45 cm soil depth. According to the overall results of two crop cycles, mulching did not statistically affect the yield. The highest yield was obtained from the full irrigation treatment with and without mulching in both cycles. Recorded total amount of irrigation water in fall and spring growing cycles were the highest in full irrigation treatments at 122 and 334 mm, respectively. Higher water consumption was determined in unmulched treatments in both growing seasons. Mulches achieved water savings of between 12 and 18%. Water consumption of tomato plants decreased with the increase of deficit levels. It was concluded that soil water content in loamy soils can be allowed to be depleted to 35% of the available water content in the plant root zone for irrigation management in tomato production under waterscarce situations, without significant decrease in yield